Merge branch 'master' of gogs:go/nix-amer

- use local self-hosted ci : drone instead of circle
- add go modules support
- update import path to be local : git.xdrm.io/go/nix-amer instead of
github.com/xdrm-brackets/nix-amer

.drone.yml

@@ -0,0 +1,11 @@
+---
+kind: pipeline
+type: docker
+name: default
+
+steps:
+- name: test
+  image: golang:1.13
+  commands:
+  - go get ./...
+  - go test -v -race -cover -coverprofile ./coverage.out ./...

README.md

@@ -1,11 +1,11 @@
 # | nix-amer |
 
 [![Go version](https://img.shields.io/badge/go_version-1.11-blue.svg)](https://golang.org/doc/go1.11)
-[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
-[![Go Report Card](https://goreportcard.com/badge/github.com/xdrm-brackets/nix-amer)](https://goreportcard.com/report/github.com/xdrm-brackets/nix-amer)
-[![Coverage Status](https://coveralls.io/repos/github/xdrm-brackets/nix-amer/badge.svg?branch=master)](https://coveralls.io/github/xdrm-brackets/nix-amer?branch=master)
-[![CircleCI Build Status](https://circleci.com/gh/xdrm-brackets/nix-amer.svg?style=shield)](https://circleci.com/gh/xdrm-brackets/nix-amer)
-[![Go doc](https://godoc.org/github.com/xdrm-brackets/nix-amer?status.svg)](https://godoc.org/github.com/xdrm-brackets/nix-amer)
+[![License: MIT](https://img.shields.io/github/license/xdrm-brackets/nix-amer.svg)](https://opensource.org/licenses/MIT)
+[![Go Report Card](https://goreportcard.com/badge/git.xdrm.io/go/nix-amer)](https://goreportcard.com/report/git.xdrm.io/go/nix-amer)
+[![Coverage Status](https://img.shields.io/coveralls/github/xdrm-brackets/nix-amer/master.svg)](https://coveralls.io/github/xdrm-brackets/nix-amer?branch=master)
+[![Build Status](https://drone.xdrm.io/api/badges/go/nix-amer/status.svg)](https://drone.xdrm.io/go/nix-amer)
+[![Go doc](https://godoc.org/git.xdrm.io/go/nix-amer?status.svg)](https://godoc.org/git.xdrm.io/go/nix-amer)
 
 ```yaml
 name:        nix-amer
@@ -25,13 +25,14 @@ author:      xdrm-brackets
         * [1. Create build file](#1-create-build-file)
         * [2. Run on the target](#2-run-on-the-target)
   * [II. Commands](#ii-commands)
-    + [1) Comments](#1-comments)
-    + [2) Install/remove Packages](#2-installremove-packages)
-    + [3) Setup configuration](#3-setup-configuration)
-    + [4) Service management](#4-service-management)
-    + [5) Custom scripts](#5-custom-scripts)
-    + [6) Copy files](#6-copy-files)
-    + [7) Aliases](#7-aliases)
+    + [1) Sections](#1-sections)
+    + [2) Comments](#2-comments)
+    + [3) Install/remove Packages](#3-installremove-packages)
+    + [4) Setup configuration](#4-setup-configuration)
+    + [5) Service management](#5-service-management)
+    + [6) Custom scripts](#6-custom-scripts)
+    + [7) Copy files](#7-copy-files)
+    + [8) Aliases](#8-aliases)
   * [III. Path Expressions](#iii-path-expressions)
     + [1) Syntax](#1-syntax)
     + [2) File Formats](#2-file-formats)
@@ -59,10 +60,10 @@ In order to install the `nix-amer` executable, you must have :
 Simply launch the following command in any terminal
 
 ```bash
-$ go get -u github.com/xdrm-brackets/nix-amer
+$ go get -u git.xdrm.io/go/nix-amer
 ```
 
-> For those who don't know, it will load the project sources into `$GOPATH/src/github.com/xdrm-brackets/nix-amer` and compile into the executable at `$GOPATH/bin/nix-amer`.
+> For those who don't know, it will load the project sources into `$GOPATH/src/git.xdrm.io/go/nix-amer` and compile into the executable at `$GOPATH/bin/nix-amer`.
 
 
 
@@ -70,7 +71,7 @@ $ go get -u github.com/xdrm-brackets/nix-amer
 
 ###### 1. Create build file
 
-The first step is to write your build file according to the installation you want. While writing your build file you can check the syntax by using the `-dry-run` command-line argument as follows :
+The first step is to write your build file according to the installation you want. While writing it you can check the syntax and validate instructions by using the `-dry-run` command-line argument as follows :
 
 ```bash
 $ nix-amer -p apt-get -dry-run <path/to/build/file>
@@ -82,7 +83,7 @@ $ nix-amer -p apt-get -dry-run <path/to/build/file>
 
 ###### 2. Run on the target
 
-Once your build file is correct and fulfills your needs, you can log in to the target machine, install the nix-amer and run it with your build file. Nix-amer's rich and colorful command-line output will give you a good feedback to rapidly fix problems.
+Once your build file is correct and fulfills your needs, you can log in to the target machine, install nix-amer and run it with your build file. The rich and colorful command-line output will give you a good feedback to rapidly fix problems.
 
 
 
@@ -94,17 +95,23 @@ Once your build file is correct and fulfills your needs, you can log in to the t
 
 ### II. Commands
 
-Your whole setup remains in 1 only build file. Each line contains one instruction, the list of instructions is listed below.
+Your whole setup remains in only one file. Each line contains one instruction, the list of instructions is listed below.
 
 
 
-#### 1) Comments
+#### 1) Sections
 
-Each line beginning with one of the following characters : `[`, `#` or `;` is considered a comment and is not interpreted.
+Each instruction is enclosed in a section (_cf. ini file format_), a section definition stands on a line where the name of the section is surrounded by `[` and `]`. Each section is executed in parallel ; the special section named `pre` is executed before every other.
 
 
 
-#### 2) Install/remove Packages
+#### 2) Comments
+
+Each line beginning with one of the following characters : `#` or `;` is considered a comment and is not interpreted.
+
+
+
+#### 3) Install/remove Packages
 
 These instructions allow you to interact with the package system available on your system.
 
@@ -122,7 +129,7 @@ Remove the listed packages. If more than one, use spaces to separate package nam
 
 
 
-#### 3) Setup configuration
+#### 4) Setup configuration
 
 This instruction allow you to set fields of configuration files without the need of an editor and in a developer-readable manner.
 
@@ -134,7 +141,7 @@ Update a configuration file where \<expr\> is a dot-separated human-readable [pa
 
 
 
-#### 4) Service management
+#### 5) Service management
 
 These instructions allow you to interact with the service system (_cf. [systemd](https://github.com/systemd/systemd)_).
 
@@ -145,7 +152,7 @@ Perform the action on services. If more than one, use spaces to separate service
 
 
 
-#### 5) Custom scripts
+#### 6) Custom scripts
 
 This instruction allows you to use custom scripts for complex operations.
 
@@ -153,9 +160,9 @@ This instruction allows you to use custom scripts for complex operations.
 run <script>
 ```
 
-Execute the executable located at the path \<script\>. If script is an [alias](#7-aliases) it will resolve to its path
+Execute the executable located at the path \<script\>. If script is an [alias](#8-aliases) it will resolve to its path
 
-#### 6) Copy files
+#### 7) Copy files
 
 This instruction allows you to copy files.
 
@@ -167,7 +174,7 @@ Try to copy the file \<src\> to the path \<dst\>.
 
 
 
-#### 7) Aliases
+#### 8) Aliases
 
 The file format allows you to create aliases to file paths for more readability in the [path expression](#ii-path-expressions) or with the [`run` command](#5-custom-scripts).
 
@@ -195,7 +202,7 @@ The syntax is pretty fast-forward, it uses 2 levels (file, fields) to find your
 
 | Field     | Description                          | Example                    |
 | --------- | :----------------------------------- | -------------------------- |
-| `location_or_alias` | Path to the configuration file to edit. The file will be created if not found. If the path is an [alias](#7-aliases) created before in the file, it will resolve to the alias value as a filename. | `/etc/nginx/nginx.conf`, `some-alias` |
+| `location_or_alias` | Path to the configuration file to edit. The file will be created if not found. If the path is an [alias](#8-aliases) created before in the file, it will resolve to the alias value as a filename. | `/etc/nginx/nginx.conf`, `some-alias` |
 | `fields` | Dot-separated chain of strings that match a configuration field. If the field does not point to a raw field but an existing field container, the \<value\> will replace the group with a text value. | `AllowGroups`, `http.gzip` |
 
 > The `fields` is processed only for known file formats listed in this [section](#2-file-formats).
@@ -212,9 +219,9 @@ Configuration files can be written according to some standards or application-sp
 
 - [yaml](https://en.wikipedia.org/wiki/YAML) with [go-yaml/yaml](https://github.com/go-yaml/yaml).
 - [ini](https://en.wikipedia.org/wiki/INI_file) with [go-ini/ini](https://github.com/go-ini/ini).
-
--  [nginx configurations](https://docs.nginx.com/nginx/admin-guide/basic-functionality/managing-configuration-files/) with [my own library](https://godoc.org/github.com/xdrm-brackets/nix-amer/internal/cnf/parser/nginx).
--  _and more to come..._
+- [nginx configurations](https://docs.nginx.com/nginx/admin-guide/basic-functionality/managing-configuration-files/) with [my own library](https://godoc.org/git.xdrm.io/go/nix-amer/internal/cnf/parser/nginx).
+- [bash sourced configurations]() with [my own library](https://godoc.org/git.xdrm.io/go/nix-amer/internal/cnf/parser/bash) (_e.g. ~/.bashrc_).
+- _and more to come..._
 
 
 
@@ -235,17 +242,13 @@ $ nix-amer -p apt-get myserver.build
 _myserver.build_
 
 ```
-[ comment starts with opening brackets '['
-
-[aliases]
-alias sshd  /etc/ssh/sshd_config
+# [pre] is executed before launching everything else
+[pre]
+install nginx ssh sslh
 alias nginx /etc/nginx/nginx.conf
+alias sshd  /etc/ssh/sshd_config
 alias sslh  /etc/default/sslh
 
-[install packages]
-install nginx ssh
-install sslh
-
 [nginx]
 set nginx@http.gzip           off
 service enable nginx

args.go

@@ -3,7 +3,7 @@ package main
 import (
 	"flag"
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/instruction"
+	"git.xdrm.io/go/nix-amer/internal/instruction"
 )
 
 // GetArgs manages cli arguments to build executionContext,

circle.yml

@@ -1,38 +0,0 @@
-version: 2
-jobs:
-  build: # runs not using Workflows must have a `build` job as entry point
-    docker:
-      - image: circleci/golang
-
-    environment: # environment variables for the build itself
-      GOPATH: /go
-      TEST_RESULTS: /tmp/test-results
-      COVER_PROFILE: /tmp/coverage.out
-
-    steps: # steps that comprise the `build` job
-      - checkout # check out source code to working directory
-      - run: mkdir -p $TEST_RESULTS # create the test results directory
-
-      - restore_cache: # restores saved cache if no changes are detected since last run
-          keys:
-            - v1-pkg-cache
-
-      - run:
-          name: Load dependencies
-          command: go get github.com/mattn/goveralls && go get github.com/go-ini/ini && go get gopkg.in/yaml.v2
-      - run:
-          name: Load nix-amer
-          command: go get github.com/xdrm-brackets/nix-amer
-      - run:
-          name: Unit tests
-          command: go test -v -cover -race -coverprofile=$COVER_PROFILE github.com/xdrm-brackets/nix-amer/...
-      - run:
-          name: Update coveralls.io
-          command: /go/bin/goveralls -coverprofile=$COVER_PROFILE -service=circle-ci -repotoken=$COVERALLS_TOKEN
-
-      - store_artifacts: # Upload test summary for display in Artifacts
-          path: /tmp/test-results
-          destination: raw-test-output
-
-      - store_test_results: # Upload test results for display in Test Summary
-          path: /tmp/test-results

go.mod

@@ -0,0 +1,8 @@
+module git.xdrm.io/go/nix-amer
+
+go 1.12
+
+require (
+	github.com/go-ini/ini v1.51.0
+	gopkg.in/yaml.v2 v2.2.5
+)

go.sum

@@ -0,0 +1,5 @@
+github.com/go-ini/ini v1.51.0 h1:VPJKXGzbKlyExUE8f41aV57yxkYx5R49yR6n7flp0M0=
+github.com/go-ini/ini v1.51.0/go.mod h1:ByCAeIL28uOIIG0E3PJtZPDL8WnHpFKFOtgjp+3Ies8=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.5 h1:ymVxjfMaHvXD8RqPRmzHHsB3VvucivSkIAvJFDI5O3c=
+gopkg.in/yaml.v2 v2.2.5/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

help.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/clifmt"
+	"git.xdrm.io/go/nix-amer/internal/clifmt"
 )
 
 func help() {

internal/buildfile/errors.go

@@ -2,7 +2,7 @@ package buildfile
 
 import (
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/clifmt"
+	"git.xdrm.io/go/nix-amer/internal/clifmt"
 )
 
 // LineError wraps errors with a line index

internal/buildfile/reader.go

@@ -4,24 +4,43 @@ import (
 	"bufio"
 	"errors"
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/clifmt"
-	"github.com/xdrm-brackets/nix-amer/internal/instruction"
+	"git.xdrm.io/go/nix-amer/internal/clifmt"
+	"git.xdrm.io/go/nix-amer/internal/instruction"
 	"io"
+	"regexp"
 	"strings"
+	"sync"
 	"time"
 )
 
 // ErrNullContext is raised when the given context is nil
 var ErrNullContext = errors.New("null context")
 
+// ErrNoParent is raised when there is an instruction but has no parent section
+var ErrNoParent = errors.New("missing parent section")
+
 // Reader is the buildfile reader
 type Reader struct {
 	// Context is the linux distribution-specified execution context (package manager, service manager, etc)
 	Context *instruction.ExecutionContext
 	// Content is the instruction list
-	Content []instruction.T
+	Content map[string]*[]instruction.T
 }
 
+type execStatus struct {
+	name    string
+	start   time.Time
+	stop    time.Time
+	stopped bool
+	err     error
+}
+type tableSection struct {
+	name         string
+	instructions []execStatus
+}
+
+var reSection = regexp.MustCompile(`(?m)^\[\s*([a-z0-9_-]+)\s*\]$`)
+
 // NewReader creates a new reader for the specified build file and linux distribution
 func NewReader(ctx *instruction.ExecutionContext, buildfile io.Reader) (*Reader, error) {
 
@@ -32,36 +51,60 @@ func NewReader(ctx *instruction.ExecutionContext, buildfile io.Reader) (*Reader,
 
 	r := &Reader{
 		Context: ctx,
-		Content: make([]instruction.T, 0),
+		Content: make(map[string]*[]instruction.T),
 	}
 
 	// add each line as instruction
 	l, reader := 0, bufio.NewReader(buildfile)
+	eof := false
+	var section *[]instruction.T // current section
 	for {
 		l++
+		if eof {
+			break
+		}
 
-		// read line until end
+		// 1. read line until end
 		line, err := reader.ReadString('\n')
 		if err == io.EOF {
-			break
+			if len(line) > 0 {
+				eof = true
+			} else {
+				break
+			}
 		} else if err != nil {
 			return nil, LineError{l, err}
 		}
 		line = strings.Trim(line, " \t\r\n")
 
-		// ignore newline & comments
-		if len(line) < 1 || strings.ContainsAny(line[0:1], "[#;") {
+		// 2. ignore newline & comments
+		if len(line) < 1 || strings.ContainsAny(line[0:1], "#;") {
 			continue
 		}
 
-		// turn into instruction
+		// 3. section
+		if match := reSection.FindStringSubmatch(line); len(match) > 1 {
+			// already in section
+			sec := make([]instruction.T, 0)
+			section = &sec
+			r.Content[match[1]] = section
+
+			continue
+		}
+
+		// 4. fail if no parent section
+		if section == nil {
+			return nil, ErrNoParent
+		}
+
+		// 5. create instruction
 		inst, err := instruction.Parse(line)
 		if err != nil {
 			return nil, LineError{l, err}
 		}
 
 		// add to list
-		r.Content = append(r.Content, inst)
+		*section = append(*section, inst)
 
 	}
 
@@ -69,7 +112,13 @@ func NewReader(ctx *instruction.ExecutionContext, buildfile io.Reader) (*Reader,
 }
 
 // Execute the current buildfile instruction by instruction
-func (r *Reader) Execute() error {
+// if <dryRun> is set to TRUE, run on dry-run mode
+func (r *Reader) Execute(_dryRun ...bool) error {
+
+	dryRun := true
+	if len(_dryRun) < 1 || !_dryRun[0] {
+		dryRun = false
+	}
 
 	// 1. update package list
 	// err := r.Context.PackageManager.Fetch()
@@ -82,26 +131,132 @@ func (r *Reader) Execute() error {
 	// if err != nil {
 	// 	return fmt.Errorf("cannot upgrade | %s", err)
 	// }
+	refresh := make(chan bool, 1)
+	wg := new(sync.WaitGroup)
+	wgstatus := new(sync.WaitGroup)
 
-	// 3. exec each instruction
-	for i, inst := range r.Content {
-		clifmt.Align(fmt.Sprintf("(%d) %s", i, clifmt.Color(0, inst.Raw())))
-		fmt.Printf("%s", clifmt.Color(33, "processing"))
+	// 1. create status table + extract [pre] section if one
+	table := make([]tableSection, 0)
+	index := make(map[string]int, 0)
 
-		start := time.Now()
+	var pre *[]instruction.T
+	var preTable *tableSection
 
-		_, err := inst.Exec(*r.Context)
-		if err != nil {
-			fmt.Printf("\r")
-			clifmt.Align(fmt.Sprintf("(%d) %s", i, clifmt.Color(0, inst.Raw())))
-			fmt.Printf("%s          \n", clifmt.Color(31, err.Error()))
-			continue
-		} else {
-			fmt.Printf("\r")
-			clifmt.Align(fmt.Sprintf("(%d) %s", i, clifmt.Color(34, inst.Raw())))
-			fmt.Printf("%ss         \n", clifmt.Color(32, fmt.Sprintf("%.2f", time.Now().Sub(start).Seconds())))
+	for secname, sec := range r.Content {
+
+		tableSec := tableSection{
+			name:         secname,
+			instructions: make([]execStatus, len(*sec), len(*sec)+1),
 		}
+
+		// for each instruction
+		for i, inst := range *sec {
+			tableSec.instructions[i].name = inst.Raw()
+		}
+
+		table = append(table, tableSec)
+		index[secname] = len(table) - 1
+
+		// [pre] section
+		if secname == "pre" {
+			pre = sec
+			preTable = &tableSec
+		}
+
+		// add one section
+		wg.Add(len(*sec))
+
 	}
 
+	// 2. launch status updater
+	wgstatus.Add(1)
+	go status(table, refresh, wgstatus)
+
+	// 3. launch [pre] (it set)
+	if pre != nil {
+		execSection(pre, *r.Context, preTable, dryRun, refresh, wg)
+		time.Sleep(time.Second * 2)
+	}
+
+	// 4. launch each other section
+	for secname, sec := range r.Content {
+		// do not launch pre again
+		if secname == "pre" {
+			continue
+		}
+		i, ok := index[secname]
+		if !ok {
+			continue
+		}
+		go execSection(sec, *r.Context, &table[i], dryRun, refresh, wg)
+	}
+
+	wg.Wait()
+	close(refresh)
+	wgstatus.Wait()
+
 	return nil
 }
+
+func execSection(section *[]instruction.T, ctx instruction.ExecutionContext, tsec *tableSection, dryRun bool, refresher chan<- bool, wg *sync.WaitGroup) {
+
+	for i, inst := range *section {
+		tsec.instructions[i].start = time.Now()
+		var err error
+		if dryRun {
+			_, err = inst.DryRun(ctx)
+		} else {
+			_, err = inst.Exec(ctx)
+
+		}
+		tsec.instructions[i].stop = time.Now()
+		tsec.instructions[i].stopped = true
+		tsec.instructions[i].err = err
+		refresher <- true
+		wg.Done()
+	}
+
+}
+
+func status(table []tableSection, refresher <-chan bool, wg *sync.WaitGroup) {
+
+	for opened := true; true; _, opened = <-refresher {
+
+		// 1. clean screen
+		fmt.Printf("\033[H\033[2J")
+
+		// 2. for each section
+		for _, sec := range table {
+
+			fmt.Printf("\n[ %s ]\n", sec.name)
+
+			// 3. for each instruction
+			for i, inst := range sec.instructions {
+
+				if !inst.stopped {
+					clifmt.Align(fmt.Sprintf("(%d) %s", i, clifmt.Color(0, inst.name)))
+					fmt.Printf("%s\n", clifmt.Color(33, "processing"))
+					continue
+				}
+
+				if inst.err != nil {
+					clifmt.Align(fmt.Sprintf("(%d) %s", i, clifmt.Color(0, inst.name)))
+					fmt.Printf("%s\n", clifmt.Color(31, inst.err.Error()))
+					continue
+				} else {
+					clifmt.Align(fmt.Sprintf("(%d) %s", i, clifmt.Color(34, inst.name)))
+					fmt.Printf("%ss\n", clifmt.Color(32, fmt.Sprintf("%.2f", inst.stop.Sub(inst.start).Seconds())))
+				}
+
+			}
+		}
+
+		if !opened {
+			break
+		}
+
+	}
+
+	wg.Done()
+
+}

internal/buildfile/reader_test.go

@@ -2,7 +2,7 @@ package buildfile
 
 import (
 	"bytes"
-	"github.com/xdrm-brackets/nix-amer/internal/instruction"
+	"git.xdrm.io/go/nix-amer/internal/instruction"
 	"testing"
 )
 
@@ -15,7 +15,7 @@ func TestNullContext(t *testing.T) {
 }
 func TestIgnoreCommentsAndEmptyLines(t *testing.T) {
 	ctx, _ := instruction.CreateContext("apt-get", "")
-	buffer := bytes.NewBufferString("[ some comment ]\n\n  \t  \n\t  \t\n[ other comment after empty lines ]")
+	buffer := bytes.NewBufferString("# some comment\n;other comment\n  \t  \n\t  \t\n; other comment after empty lines")
 
 	r, err := NewReader(ctx, buffer)
 	if err != nil {
@@ -33,24 +33,24 @@ func TestInstructionSyntax(t *testing.T) {
 		Line int
 		Err  error
 	}{
-		{"install args\ndelete args\n", 0, nil},
-		{" install args\ndelete args\n", 0, nil},
-		{"\tinstall args\ndelete args\n", 0, nil},
-		{" \t install args\ndelete args\n", 0, nil},
-		{" \t install args\ndelete args\n", 0, nil},
+		{"[pre]\ninstall args\ndelete args\n", 1, nil},
+		{"[pre]\n install args\ndelete args\n", 1, nil},
+		{"[pre]\n\tinstall args\ndelete args\n", 1, nil},
+		{"[pre]\n \t install args\ndelete args\n", 1, nil},
+		{"[pre]\n \t install args\ndelete args\n", 1, nil},
 
-		{"cmd args\ncmd args\n", 1, instruction.ErrUnknownInstruction},
-		{"install args\ncmd args\n", 2, instruction.ErrUnknownInstruction},
-		{" cmd args\ncmd args\n", 1, instruction.ErrUnknownInstruction},
-		{"\tcmd args\ncmd args\n", 1, instruction.ErrUnknownInstruction},
-		{" \t cmd args\ncmd args\n", 1, instruction.ErrUnknownInstruction},
-		{" \t cmd args\ncmd args\n", 1, instruction.ErrUnknownInstruction},
+		{"[pre]\ncmd args\ncmd args\n", 2, instruction.ErrUnknownInstruction},
+		{"[pre]\ninstall args\ncmd args\n", 3, instruction.ErrUnknownInstruction},
+		{"[pre]\n cmd args\ncmd args\n", 2, instruction.ErrUnknownInstruction},
+		{"[pre]\n\tcmd args\ncmd args\n", 2, instruction.ErrUnknownInstruction},
+		{"[pre]\n \t cmd args\ncmd args\n", 2, instruction.ErrUnknownInstruction},
+		{"[pre]\n \t cmd args\ncmd args\n", 2, instruction.ErrUnknownInstruction},
 
-		{"cmd args\ncmd\n", 1, instruction.ErrUnknownInstruction},
-		{"install\ncmd args\n", 1, instruction.ErrInvalidSyntax},
+		{"[pre]\ncmd args\ncmd\n", 2, instruction.ErrUnknownInstruction},
+		{"[pre]\ninstall\ncmd args\n", 2, instruction.ErrInvalidSyntax},
 
-		{"install args\n cmd args\n", 2, instruction.ErrUnknownInstruction},
-		{"install args\ncmd\n", 2, instruction.ErrInvalidSyntax},
+		{"[pre]\ninstall args\n cmd args\n", 3, instruction.ErrUnknownInstruction},
+		{"[pre]\ninstall args\ncmd\n", 3, instruction.ErrInvalidSyntax},
 	}
 
 	ctx, _ := instruction.CreateContext("apt-get", "")
@@ -64,7 +64,11 @@ func TestInstructionSyntax(t *testing.T) {
 		// no error expected
 		if test.Err == nil {
 			if err != nil {
-				lineerr := err.(LineError)
+				lineerr, ok := err.(LineError)
+				if !ok {
+					t.Errorf("[%d] expect error to be of type <LineError>", i)
+					continue
+				}
 				t.Errorf("[%d] expect no error, got <%s>", i, lineerr.Err)
 			}
 			continue

internal/clifmt/symbols.go

@@ -92,7 +92,7 @@ func DisplaySize(s string) int {
 	matches = reDots.FindAllString(s, -1)
 	for _, m := range matches {
 		size -= len(m)
-		size += 1
+		size++
 	}
 
 	return size

internal/cnf/bash.go

@@ -0,0 +1,99 @@
+package cnf
+
+import (
+	lib "git.xdrm.io/go/nix-amer/internal/cnf/parser/bash"
+	"io"
+	"strings"
+)
+
+type bash struct {
+	data   *lib.File
+	parsed bool
+}
+
+// ReadFrom implements io.ReaderFrom
+func (d *bash) ReadFrom(_reader io.Reader) (int64, error) {
+
+	d.data = new(lib.File)
+
+	// 1. get bash decoder
+	decoder := lib.NewDecoder(_reader)
+	err := decoder.Decode(d.data)
+	if err != nil {
+		return 0, err
+	}
+
+	d.parsed = true
+	return 0, nil
+
+}
+
+// WriteTo implements io.WriterTo
+func (d *bash) WriteTo(_writer io.Writer) (int64, error) {
+	encoder := lib.NewEncoder(_writer)
+	return 0, encoder.Encode(d.data)
+}
+
+// browse returns the target of a dot-separated path (as an interface{} chain where the last is the target if found)
+// if <create> is true, create if does not exist
+func (d *bash) browse(_path string, create ...bool) (*lib.Line, bool) {
+
+	mustCreate := len(create) > 0 && create[0]
+
+	// 1. extract path
+	path := strings.Split(_path, ".")
+	field := path[len(path)-1]
+
+	// 2. nothing
+	if len(path) < 1 {
+		return &lib.Line{}, true
+	}
+
+	// 3. iterate over path / nested fields
+	for _, line := range d.data.Lines {
+		if line.Type == lib.ASSIGNMENT && len(line.Components) > 1 && line.Components[1] == field {
+			return line, true
+		}
+	}
+
+	// 4. create assignment
+	if mustCreate {
+		assignment := &lib.Line{
+			Type:       lib.ASSIGNMENT,
+			Components: []string{"", field, "", ""},
+		}
+		d.data.Lines = append(d.data.Lines, assignment)
+		return assignment, true
+	}
+
+	return nil, false
+}
+
+// Get returns the value of a dot-separated path, and if it exists
+func (d *bash) Get(_path string) (string, bool) {
+
+	// 1. browse path
+	last, found := d.browse(_path, true)
+	if !found {
+		return "", false
+	}
+
+	// 2. Get last field
+	return last.Components[2], true
+
+}
+
+// Set the value of a dot-separated path, and creates it if not found
+func (d *bash) Set(_path, _value string) bool {
+
+	// 1. browse path
+	last, found := d.browse(_path, true)
+	if !found {
+		return false
+	}
+
+	// 2. Set value
+	last.Components[2] = _value
+	return true
+
+}

internal/cnf/bash_test.go

@@ -0,0 +1,220 @@
+package cnf
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestBashGet(t *testing.T) {
+
+	tests := []struct {
+		raw string
+		key string
+	}{
+		{"key=value;\n", "key"},
+		{"  \t key=value;\n", "key"},
+		{"key=value; #comment\n", "key"},
+		{"\t   key=value; #comment\n", "key"},
+		{"key=value; # comment\n", "key"},
+		{"\t \tkey=value; # comment\n", "key"},
+	}
+
+	for i, test := range tests {
+
+		parser := new(bash)
+		reader := bytes.NewBufferString(test.raw)
+
+		// try to extract value
+		_, err := parser.ReadFrom(reader)
+		if err != nil {
+			t.Errorf("[%d] parse error: %s", i, err)
+			continue
+		}
+
+		// extract value
+		value, found := parser.Get(test.key)
+		if !found {
+			t.Errorf("[%d] expected a result, got none", i)
+			continue
+		}
+
+		// check value
+		if value != "value" {
+			t.Errorf("[%d] expected 'value' got '%s'", i, value)
+		}
+
+	}
+
+}
+
+func TestBashSetPathExists(t *testing.T) {
+
+	tests := []struct {
+		raw   string
+		key   string
+		value string
+	}{
+
+		{"key=value;\n", "key", "newvalue"},
+		{"  \t key=value;\n", "key", "newvalue"},
+		{"key=value; #comment\n", "key", "newvalue"},
+		{"\t   key=value; #comment\n", "key", "newvalue"},
+		{"key=value; # comment\n", "key", "newvalue"},
+		{"\t \tkey=value; # comment\n", "key", "newvalue"},
+	}
+
+	for i, test := range tests {
+
+		parser := new(bash)
+		reader := bytes.NewBufferString(test.raw)
+
+		// try to extract value
+		_, err := parser.ReadFrom(reader)
+		if err != nil {
+			t.Errorf("[%d] parse error: %s", i, err)
+			continue
+		}
+
+		// update value
+		if !parser.Set(test.key, test.value) {
+			t.Errorf("[%d] cannot set '%s' to '%s'", i, test.key, test.value)
+			continue
+		}
+
+		// check new value
+		value, found := parser.Get(test.key)
+		if !found {
+			t.Errorf("[%d] expected a result, got none", i)
+			continue
+		}
+
+		// check value
+		if value != test.value {
+			t.Errorf("[%d] expected '%s' got '%s'", i, test.value, value)
+		}
+
+	}
+
+}
+
+func TestBashSetCreatePath(t *testing.T) {
+
+	tests := []struct {
+		raw    string
+		key    string
+		ignore string // path to field that must be present after transformation
+		value  string
+	}{
+		{"ignore=xxx;\n", "key", "ignore", "newvalue"},
+		{"unknown-line\nignore=xxx;\n", "key", "ignore", "newvalue"},
+	}
+
+	for i, test := range tests {
+
+		parser := new(bash)
+		reader := bytes.NewBufferString(test.raw)
+
+		// try to extract value
+		_, err := parser.ReadFrom(reader)
+		if err != nil {
+			t.Errorf("[%d] parse error: %s", i, err)
+			continue
+		}
+
+		// update value
+		if !parser.Set(test.key, test.value) {
+			t.Errorf("[%d] cannot set '%s' to '%s'", i, test.key, test.value)
+			continue
+		}
+
+		// check new value
+		value, found := parser.Get(test.key)
+		if !found {
+			t.Errorf("[%d] expected a result, got none", i)
+			continue
+		}
+
+		// check value
+		if value != test.value {
+			t.Errorf("[%d] expected '%s' got '%s'", i, test.value, value)
+			continue
+		}
+
+		// check that ignore field is still there
+		value, found = parser.Get(test.ignore)
+		if !found {
+			t.Errorf("[%d] expected ignore field, got none", i)
+			continue
+		}
+
+		// check value
+		if value != "xxx" {
+			t.Errorf("[%d] expected ignore value to be '%s' got '%s'", i, "xxx", value)
+			continue
+		}
+	}
+
+}
+
+func TestBashSetCreateEncode(t *testing.T) {
+
+	tests := []struct {
+		raw     string
+		key     string
+		value   string
+		encoded string
+	}{
+		{"ignore=xxx;\n", "key", `"newvalue"`, "ignore=xxx;\nkey=\"newvalue\";\n"},
+		{"#!/bin/bash\n\nfunc(){\n\techo \"something\";\n}\nignore=xxx;\n", "key", `"newvalue"`, "#!/bin/bash\nfunc(){\n\techo \"something\";\n}\nignore=xxx;\nkey=\"newvalue\";\n"},
+	}
+
+	for i, test := range tests {
+
+		parser := new(bash)
+		r, w := bytes.NewBufferString(test.raw), new(bytes.Buffer)
+
+		// try to extract value
+		_, err := parser.ReadFrom(r)
+		if err != nil {
+			t.Errorf("[%d] parse error: %s", i, err)
+			continue
+		}
+
+		// update value
+		if !parser.Set(test.key, test.value) {
+			t.Errorf("[%d] cannot set '%s' to '%s'", i, test.key, test.value)
+			continue
+		}
+
+		// check new value
+		value, found := parser.Get(test.key)
+		if !found {
+			t.Errorf("[%d] expected a result, got none", i)
+			continue
+		}
+
+		// check value
+		if value != test.value {
+			t.Errorf("[%d] expected '%s' got '%s'", i, test.value, value)
+			continue
+		}
+
+		// writeToBuffer
+		_, err = parser.WriteTo(w)
+		if err != nil {
+			t.Errorf("[%d] unexpected write error <%s>", i, err)
+			continue
+		}
+
+		encoded := w.String()
+
+		// check value
+		if encoded != test.encoded {
+			t.Errorf("[%d] wrong encoded value \n-=-=-= HAVE =-=-=-\n%s\n-=-=-= WANT =-=-=-\n%s\n-=-=-=-=-=\n", i, escape(test.encoded), escape(encoded))
+			continue
+		}
+
+		// try to write
+	}
+
+}

internal/cnf/ini.go

@@ -16,8 +16,15 @@ type ini struct {
 // ReadFrom implements io.ReaderFrom
 func (d *ini) ReadFrom(_reader io.Reader) (int64, error) {
 
+	// disallow "key: value"
+	// when trying to find out the format from content
+	// and avoids conflicts with YAML
+	opts := lib.LoadOptions{
+		KeyValueDelimiters: "=",
+	}
+
+	file, err := lib.LoadSources(opts, ioutil.NopCloser(_reader))
 	// 1. get json decoder
-	file, err := lib.Load(ioutil.NopCloser(_reader))
 	if err != nil {
 		return 0, err
 	}

internal/cnf/loader.go

@@ -2,8 +2,6 @@ package cnf
 
 import (
 	"errors"
-	"fmt"
-	"io"
 	"os"
 	"path/filepath"
 )
@@ -14,51 +12,45 @@ var ErrUnknownExtension = errors.New("unknown extension format")
 // ErrUnknownFormat is raised when the format cannot be guessed from the content of the file
 var ErrUnknownFormat = errors.New("cannot infer format from content")
 
+// ErrFileNotExist is raised when required file does not exist
+var ErrFileNotExist = errors.New("cannot find file")
+
 // Load the current file and create the configuration format accordingly
 func Load(path string) (ConfigurationFormat, error) {
 
-	var confFormat ConfigurationFormat
-
 	// 1. check file
 	if _, err := os.Stat(path); os.IsNotExist(err) {
-		return nil, fmt.Errorf("cannot find file '%s'", path)
+		return nil, ErrFileNotExist
 	}
 
 	// 2. Try to load from extension
 	extension := filepath.Ext(path)
 	if len(extension) > 0 {
 
-		confFormat = loadFromExtension(extension)
-		if confFormat == nil {
-			return nil, ErrUnknownExtension
-		}
+		if confFormat := loadFromExtension(extension); confFormat != nil {
 
-		// open file
-		file, err := os.Open(path)
-		if err != nil {
-			return nil, err
-		}
-		defer file.Close()
+			// open file
+			file, err := os.Open(path)
+			if err != nil {
+				return nil, err
+			}
 
-		// parse
-		_, err = confFormat.ReadFrom(file)
-		if err == nil {
-			return confFormat, nil
-		}
+			// parse
+			_, err = confFormat.ReadFrom(file)
+			file.Close()
+			if err == nil {
+				return confFormat, nil
+			}
 
-		// return nil, fmt.Errorf("cannot parse file as '%s' | %s", extension, err)
+		}
 
 	}
 
-	// 3. open file
-	file, err := os.Open(path)
+	// 4. Try to guess from the content
+	confFormat, err := loadFromContent(path)
 	if err != nil {
 		return nil, err
 	}
-	defer file.Close()
-
-	// 4. Try to guess from the content
-	confFormat = loadFromContent(file)
 	if confFormat == nil {
 		return nil, ErrUnknownFormat
 	}
@@ -78,19 +70,29 @@ func loadFromExtension(ext string) ConfigurationFormat {
 		return new(yaml)
 	case ".nginx":
 		return new(nginx)
+	case ".sh":
+		return new(bash)
 	default:
 		return nil
 	}
 
 }
 
-func loadFromContent(file io.Reader) ConfigurationFormat {
+func loadFromContent(path string) (ConfigurationFormat, error) {
 
-	// extensions ordered by unicity of the language's syntax
-	extensions := []string{".json", ".yaml", ".nginx", ".ini"}
+	// 3. open file
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	// extensions ordered by strictness of the language's syntax
+	extensions := []string{".json", ".nginx", ".ini", ".yaml", ".sh"}
 
 	// try to load each available extension
 	for _, ext := range extensions {
+		file.Seek(0, 0)
 
 		// load parser
 		c := loadFromExtension(ext)
@@ -101,10 +103,10 @@ func loadFromContent(file io.Reader) ConfigurationFormat {
 		// parse
 		_, err := c.ReadFrom(file)
 		if err == nil {
-			return c
+			return c, nil
 		}
 
 	}
 
-	return nil
+	return nil, ErrUnknownFormat
 }

internal/cnf/loader_test.go

@@ -0,0 +1,250 @@
+package cnf
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+func TestLoadFileNotExist(t *testing.T) {
+
+	_, err := Load("/tmp/not-existing/file")
+	if err == nil {
+		t.Fatalf("expected error")
+	}
+	if err != ErrFileNotExist {
+		t.Fatalf("expected error <%s>, got <%s>", ErrFileNotExist, err)
+	}
+
+}
+func TestLoadFromExtensionWithContentMatch(t *testing.T) {
+
+	tests := []struct {
+		File    string
+		Format  ConfigurationFormat
+		Content string
+		Field   string
+	}{
+
+		// key = value
+		{"/tmp/load-test.json", new(json), `{ "key": "value" }`, "key"},
+		{"/tmp/load-test.nginx", new(nginx), "key value;", "key"},
+		{"/tmp/load-test.ini", new(ini), `key = value`, "key"},
+		{"/tmp/load-test.yaml", new(yaml), "key: value", "key"},
+
+		// parent.key = value
+		{"/tmp/load-test.json", new(json), `{ "parent": { "key": "value" } }`, "parent.key"},
+		{"/tmp/load-test.nginx", new(nginx), "parent {\nkey value;\n}", "parent.key"},
+		{"/tmp/load-test.ini", new(ini), "[parent]\nkey = value", "parent.key"},
+		{"/tmp/load-test.yaml", new(yaml), "parent:\n  key: value", "parent.key"},
+
+		// comments
+		// {"/tmp/load-test.json", new(json), "{ \"parent\": { \"key\": \"value\" } }", "parent.key"},
+		{"/tmp/load-test.nginx", new(nginx), ";comment\nparent {\nkey value;\n}", "parent.key"},
+		{"/tmp/load-test.nginx", new(nginx), "#comment\nparent {\nkey value;\n}", "parent.key"},
+		{"/tmp/load-test.ini", new(ini), ";comment\n[parent]\nkey = value", "parent.key"},
+		{"/tmp/load-test.ini", new(ini), "#comment\n[parent]\nkey = value", "parent.key"},
+		{"/tmp/load-test.yaml", new(yaml), "#comment\nparent:\n  key: value", "parent.key"},
+	}
+
+	for i, test := range tests {
+
+		f, err := os.Create(test.File)
+		if err != nil {
+			t.Errorf("[%d] cannot create file '%s'", i, test.File)
+			continue
+		}
+		f.Write([]byte(test.Content))
+		f.Close()
+
+		format, err := Load(test.File)
+		if err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+		if format == nil {
+			t.Errorf("[%d] expected format not to be null", i)
+			continue
+		}
+
+		// check type
+		have, want := fmt.Sprintf("%T", format), fmt.Sprintf("%T", test.Format)
+		if have != want {
+			t.Errorf("[%d] expected format <%s>, got <%s>", i, want, have)
+			continue
+		}
+
+		// try to get value
+		val, found := format.Get(test.Field)
+		if !found {
+			t.Errorf("[%d] expected to find '%s'", i, test.Field)
+			continue
+		}
+
+		if val != "value" {
+			t.Errorf("[%d] expected value '%s', got '%s'", i, "value", val)
+			continue
+		}
+
+	}
+
+	for _, test := range tests {
+		os.RemoveAll(test.File)
+	}
+
+}
+
+func TestLoadFromExtensionWithContentNotMatch(t *testing.T) {
+
+	tests := []struct {
+		File    string
+		Format  ConfigurationFormat
+		Content string
+		Field   string
+	}{
+
+		// [JSON] key = value
+		{"/tmp/load-test.json", new(json), `{ "key": "value" }`, "key"},
+		{"/tmp/load-test.nginx", new(json), `{ "key": "value" }`, "key"},
+		{"/tmp/load-test.ini", new(json), `{ "key": "value" }`, "key"},
+		// {"/tmp/load-test.yaml", new(json), `{ "key": "value" }`, "key"},
+
+		// [NGINX] key = value
+		{"/tmp/load-test.json", new(nginx), "key value;", "key"},
+		{"/tmp/load-test.nginx", new(nginx), "key value;", "key"},
+		{"/tmp/load-test.ini", new(nginx), "key value;", "key"},
+		// {"/tmp/load-test.yaml", new(nginx), "key value;", "key"},
+
+		// [INI] key = value
+		{"/tmp/load-test.json", new(ini), `key = value`, "key"},
+		{"/tmp/load-test.nginx", new(ini), `key = value`, "key"},
+		{"/tmp/load-test.ini", new(ini), `key = value`, "key"},
+		// {"/tmp/load-test.yaml", new(ini), `key = value`, "key"},
+
+		// [YAML] key = value
+		{"/tmp/load-test.json", new(yaml), "key: value", "key"},
+		{"/tmp/load-test.nginx", new(yaml), "key: value", "key"},
+		{"/tmp/load-test.yaml", new(yaml), "key: value", "key"},
+		{"/tmp/load-test.yaml", new(yaml), "key: value", "key"},
+	}
+
+	for i, test := range tests {
+
+		f, err := os.Create(test.File)
+		if err != nil {
+			t.Errorf("[%d] cannot create file '%s'", i, test.File)
+			continue
+		}
+		f.Write([]byte(test.Content))
+		f.Close()
+
+		format, err := Load(test.File)
+		if err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+		if format == nil {
+			t.Errorf("[%d] expected format not to be null", i)
+			continue
+		}
+
+		// check type
+		have, want := fmt.Sprintf("%T", format), fmt.Sprintf("%T", test.Format)
+		if have != want {
+			t.Errorf("[%d] expected format <%s>, got <%s>", i, want, have)
+			continue
+		}
+
+		// try to get value
+		val, found := format.Get(test.Field)
+		if !found {
+			t.Errorf("[%d] expected to find '%s'", i, test.Field)
+			continue
+		}
+
+		if val != "value" {
+			t.Errorf("[%d] expected value '%s', got '%s'", i, "value", val)
+			continue
+		}
+
+	}
+	for _, test := range tests {
+		os.RemoveAll(test.File)
+	}
+
+}
+func TestLoadContent(t *testing.T) {
+
+	file := "/tmp/no-extension-file"
+	defer os.RemoveAll(file)
+
+	tests := []struct {
+		Format  ConfigurationFormat
+		Content string
+		Field   string
+	}{
+
+		// key = value
+		{new(json), `{ "key": "value" }`, "key"},
+		{new(nginx), "key value;", "key"},
+		{new(ini), `key = value`, "key"},
+		{new(yaml), "key: value", "key"},
+
+		// parent.key = value
+		{new(json), `{ "parent": { "key": "value" } }`, "parent.key"},
+		{new(nginx), "parent {\nkey value;\n}", "parent.key"},
+		{new(ini), "[parent]\nkey = value", "parent.key"},
+		{new(yaml), "parent:\n  key: value", "parent.key"},
+
+		// comments
+		{new(json), "{ \"parent\": { \"key\": \"value\" } }", "parent.key"},
+		{new(nginx), ";comment\nparent {\nkey value;\n}", "parent.key"},
+		{new(nginx), "#comment\nparent {\nkey value;\n}", "parent.key"},
+		{new(ini), ";comment\n[parent]\nkey = value", "parent.key"},
+		{new(ini), "#comment\n[parent]\nkey = value", "parent.key"},
+		{new(yaml), "#comment\nparent:\n  key: value", "parent.key"},
+	}
+
+	for i, test := range tests {
+
+		os.RemoveAll(file)
+		f, err := os.Create(file)
+		if err != nil {
+			t.Errorf("[%d] cannot create file '%s'", i, file)
+			continue
+		}
+		f.Write([]byte(test.Content))
+		f.Close()
+
+		format, err := Load(file)
+		if err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+		if format == nil {
+			t.Errorf("[%d] expected format not to be null", i)
+			continue
+		}
+
+		// check type
+		have, want := fmt.Sprintf("%T", format), fmt.Sprintf("%T", test.Format)
+		if have != want {
+			t.Errorf("[%d] expected format <%s>, got <%s>", i, want, have)
+			continue
+		}
+
+		// try to get value
+		val, found := format.Get(test.Field)
+		if !found {
+			t.Errorf("[%d] expected to find '%s'", i, test.Field)
+			continue
+		}
+
+		if val != "value" {
+			t.Errorf("[%d] expected value '%s', got '%s'", i, "value", val)
+			continue
+		}
+
+	}
+
+}

internal/cnf/nginx.go

@@ -1,7 +1,7 @@
 package cnf
 
 import (
-	lib "github.com/xdrm-brackets/nix-amer/internal/cnf/parser/nginx"
+	lib "git.xdrm.io/go/nix-amer/internal/cnf/parser/nginx"
 	"io"
 	"strings"
 )
@@ -78,6 +78,7 @@ func (d *nginx) browse(_path string, create ...bool) (*lib.Line, bool) {
 					Lines:      make([]*lib.Line, 0),
 				}
 				current.Lines = append(current.Lines, sec)
+				current = sec
 				continue
 			}
 

internal/cnf/nginx_test.go

@@ -102,6 +102,7 @@ func TestNginxSetCreatePath(t *testing.T) {
 		{"ignore xxx;\n", "key", "ignore", "newvalue"},
 		{"ignore xxx;\nsection {\n\tkey value;\n}\n", "section.key", "ignore", "newvalue"},
 		{"section {\n\tkey value;\n\tignore xxx;\n}\n", "section.key", "section.ignore", "newvalue"},
+		{"ignoresec {\n\tignore xxx;\n}\n\nsection {\n}\n", "section.key", "ignoresec.ignore", "newvalue"},
 		{"ignoresec {\n\tignore xxx;\n}\n\nsection {\n\tkey value;\n}\n", "section.key", "ignoresec.ignore", "newvalue"},
 	}
 
@@ -151,3 +152,103 @@ func TestNginxSetCreatePath(t *testing.T) {
 	}
 
 }
+
+func TestNginxSetCreateEncode(t *testing.T) {
+
+	tests := []struct {
+		raw     string
+		key     string
+		value   string
+		encoded string
+	}{
+		{"ignore xxx;\n", "key", "newvalue", "ignore\t\txxx;\nkey\t\tnewvalue;\n"},
+		{"ignore xxx;\nsection {\n\tkey value;\n}\n", "section.key", "newvalue", "ignore\t\txxx;\nsection {\n\tkey\t\tnewvalue;\n}\n\n"},
+		{"section {\n\tkey value;\n\tignore xxx;\n}\n", "section.key", "newvalue", "section {\n\tkey\t\tnewvalue;\n\tignore\t\txxx;\n}\n\n"},
+		{"ignoresec {\n\tignore xxx;\n}\n\nsection {\n}\n", "section.key", "newvalue", "ignoresec {\n\tignore\t\txxx;\n}\n\nsection {\n\tkey\t\tnewvalue;\n}\n\n"},
+		{"ignoresec {\n\tignore xxx;\n}\n\nsection {\n\tkey value;\n}\n", "section.key", "newvalue", "ignoresec {\n\tignore\t\txxx;\n}\n\nsection {\n\tkey\t\tnewvalue;\n}\n\n"},
+
+		{
+			"; comment 1\n\nk1 v1;\n#comment 2\nsec1 {\n}\nsec2 {\nignore xxx;\n sec3 {\nignore2 yyy;\n}\n\n}\n\n",
+			"key",
+			"newvalue",
+			"; comment 1\nk1\t\tv1;\n#comment 2\nsec1 {\n}\n\nsec2 {\n\tignore\t\txxx;\n\tsec3 {\n\t\tignore2\t\tyyy;\n\t}\n\n}\n\nkey\t\tnewvalue;\n"},
+		{
+			"; comment 1\n\nk1 v1;\n#comment 2\nsec1 {\n}\nsec2 {\nignore xxx;\n sec3 {\nignore2 yyy;\n}\n\n}\n\n",
+			"section.key",
+			"newvalue",
+			"; comment 1\nk1\t\tv1;\n#comment 2\nsec1 {\n}\n\nsec2 {\n\tignore\t\txxx;\n\tsec3 {\n\t\tignore2\t\tyyy;\n\t}\n\n}\n\nsection {\n\tkey\t\tnewvalue;\n}\n\n"},
+	}
+
+	for i, test := range tests {
+
+		parser := new(nginx)
+		r, w := bytes.NewBufferString(test.raw), new(bytes.Buffer)
+
+		// try to extract value
+		_, err := parser.ReadFrom(r)
+		if err != nil {
+			t.Errorf("[%d] parse error: %s", i, err)
+			continue
+		}
+
+		// update value
+		if !parser.Set(test.key, test.value) {
+			t.Errorf("[%d] cannot set '%s' to '%s'", i, test.key, test.value)
+			continue
+		}
+
+		// check new value
+		value, found := parser.Get(test.key)
+		if !found {
+			t.Errorf("[%d] expected a result, got none", i)
+			continue
+		}
+
+		// check value
+		if value != test.value {
+			t.Errorf("[%d] expected '%s' got '%s'", i, test.value, value)
+			continue
+		}
+
+		// writeToBuffer
+		_, err = parser.WriteTo(w)
+		if err != nil {
+			t.Errorf("[%d] unexpected write error <%s>", i, err)
+			continue
+		}
+
+		encoded := w.String()
+
+		// check value
+		if encoded != test.encoded {
+			t.Errorf("[%d] wrong encoded value \n-=-=-= HAVE =-=-=-\n%s\n-=-=-= WANT =-=-=-\n%s\n-=-=-=-=-=\n", i, escape(test.encoded), escape(encoded))
+			continue
+		}
+
+		// try to write
+	}
+
+}
+
+func escape(in string) string {
+
+	out := make([]rune, 0)
+
+	for _, char := range in {
+		if char == '\\' {
+			out = append(out, []rune("\\\\")...)
+		} else if char == '\n' {
+			out = append(out, []rune("\\n")...)
+		} else if char == '\r' {
+			out = append(out, []rune("\\r")...)
+		} else if char == '\t' {
+			out = append(out, []rune("\\t")...)
+		} else if char == '\033' {
+			out = append(out, []rune("\\033")...)
+		} else {
+			out = append(out, char)
+		}
+	}
+
+	return string(out)
+}

internal/cnf/parser/bash/bash.go

@@ -0,0 +1,20 @@
+package bash
+
+import (
+	"io"
+)
+
+// File represents a bash file
+type File struct {
+	Lines []*Line
+}
+
+// NewDecoder implements parser.T
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{reader: r}
+}
+
+// NewEncoder implements parser.T
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{writer: w}
+}

internal/cnf/parser/bash/decoder.go

@@ -0,0 +1,74 @@
+package bash
+
+import (
+	"bufio"
+	"io"
+	"regexp"
+	"strings"
+)
+
+// Decoder implements parser.Decoder
+type Decoder struct{ reader io.Reader }
+
+// Decode is the main function of the parser.Decoder interface
+func (d *Decoder) Decode(v interface{}) error {
+
+	// check 'v'
+	if v == nil {
+		return ErrNullReceiver
+	}
+	vcast, ok := v.(*File)
+	if !ok {
+		return ErrInvalidReceiver
+	}
+	vcast.Lines = make([]*Line, 0)
+
+	r := bufio.NewReader(d.reader)
+	n := -1 // line number
+
+	// regexes
+	reAssign := regexp.MustCompile(`(?m)^(\s*)([A-Za-z0-9_]+)=([^;]+);?\s*(#.+)?$`)
+	eof := false
+
+	for {
+		n++
+		if eof {
+			break
+		}
+
+		l := &Line{Type: ANY}
+
+		// 1. read line
+		line, err := r.ReadString('\n')
+		if err == io.EOF {
+			if len(line) > 0 {
+				eof = true
+			} else {
+				break
+			}
+		} else if err != nil {
+			return &LineError{n, err}
+		}
+		line = strings.Trim(line, "\r\n")
+
+		// 2. ignore empty
+		if len(strings.Trim(line, " \t\r\n")) < 1 {
+			continue
+		}
+
+		// 3. assignment
+		match := reAssign.FindStringSubmatch(line)
+		if match != nil {
+			l.Type = ASSIGNMENT
+			l.Components = match[1:]
+		} else {
+			l.Components = []string{line}
+		}
+
+		// 4. add to file
+		vcast.Lines = append(vcast.Lines, l)
+
+	}
+
+	return nil
+}

internal/cnf/parser/bash/encoder.go

@@ -0,0 +1,59 @@
+package bash
+
+import (
+	"fmt"
+	"io"
+	"strings"
+)
+
+// Encoder implements parser.Encoder
+type Encoder struct {
+	writer io.Writer
+	prefix []byte
+	indent []byte
+}
+
+// Encode is the main function of the parser.Encoder interface
+func (e *Encoder) Encode(v interface{}) error {
+
+	// check 'v'
+	vcast, ok := v.(*File)
+	if !ok {
+		return ErrInvalidReceiver
+	}
+
+	// empty config
+	if len(vcast.Lines) < 1 {
+		return nil
+	}
+
+	for _, line := range vcast.Lines {
+
+		// line representation
+		repr := ""
+
+		// ASSIGNMENT
+		if line.Type == ASSIGNMENT {
+			repr = fmt.Sprintf("%s%s=%s;", line.Components[0], line.Components[1], line.Components[2])
+
+			// optional comment
+			if len(line.Components[3]) > 0 {
+				repr += fmt.Sprintf(" %s", line.Components[3])
+			}
+
+			// ANY
+		} else {
+			repr = strings.Join(line.Components, "")
+		}
+
+		repr += "\n"
+
+		_, err := e.writer.Write([]byte(repr))
+		if err != nil {
+			return err
+		}
+
+	}
+
+	return nil
+}

internal/cnf/parser/bash/errors.go

@@ -0,0 +1,23 @@
+package bash
+
+import (
+	"fmt"
+	"git.xdrm.io/go/nix-amer/internal/clifmt"
+)
+
+// ErrNullReceiver is raised when a null receiver is provided
+var ErrNullReceiver = fmt.Errorf("receiver must not be null")
+
+// ErrInvalidReceiver is raised when an invalid receiver is provided
+var ErrInvalidReceiver = fmt.Errorf("receiver must be compatible with *File")
+
+// LineError wraps errors with a line index
+type LineError struct {
+	Line int
+	Err  error
+}
+
+// Error implements Error
+func (le LineError) Error() string {
+	return fmt.Sprintf(":%d %s", le.Line, clifmt.Color(31, le.Err.Error()))
+}

internal/cnf/parser/bash/line.go

@@ -0,0 +1,26 @@
+package bash
+
+// LineType enumerates available line types
+type LineType byte
+
+const (
+	// ANY is the default line type (all except assignments)
+	ANY LineType = iota
+	// ASSIGNMENT line
+	ASSIGNMENT
+)
+
+// Line represents a meaningful line
+type Line struct {
+	// Type of line
+	Type LineType
+
+	// Components of the line
+	//
+	// When Type = ASSIGNMENT :
+	//  [0] = indentation (spaces and tabs)
+	//  [1] = variable name
+	//  [2] = variable value
+	//  [3] = comment (optional)
+	Components []string
+}

internal/cnf/parser/nginx/decoder.go

@@ -153,5 +153,4 @@ func (d *Decoder) Decode(v interface{}) error {
 	}
 
 	return nil
-
 }

internal/cnf/parser/nginx/decoder_test.go

@@ -201,12 +201,12 @@ func TestReceiverAndSyntaxErrors(t *testing.T) {
 	}
 }
 
-var readerError = errors.New("error")
+var errReader = errors.New("error")
 
 type defectiveReader struct{}
 
 func (d defectiveReader) Read(buf []byte) (int, error) {
-	return 0, readerError
+	return 0, errReader
 }
 func TestReadErrors(t *testing.T) {
 
@@ -221,8 +221,8 @@ func TestReadErrors(t *testing.T) {
 		t.Fatalf("expected error")
 	}
 
-	if err.Error() != (&LineError{0, readerError}).Error() {
-		t.Fatalf("expected error <%s>, got <%s>", &LineError{0, readerError}, err)
+	if err.Error() != (&LineError{0, errReader}).Error() {
+		t.Fatalf("expected error <%s>, got <%s>", &LineError{0, errReader}, err)
 	}
 
 }

internal/cnf/parser/nginx/encoder_test.go

@@ -167,12 +167,12 @@ func TestDefaultIndent(t *testing.T) {
 	}
 }
 
-var writerError = errors.New("error")
+var errWriter = errors.New("error")
 
 type defectiveWriter struct{}
 
 func (d defectiveWriter) Write(buf []byte) (int, error) {
-	return 0, writerError
+	return 0, errWriter
 }
 
 func TestWriteError(t *testing.T) {
@@ -191,8 +191,8 @@ func TestWriteError(t *testing.T) {
 
 	// encode back to writer
 	encoder := NewEncoder(w)
-	if err := encoder.Encode(receiver); err != writerError {
-		t.Fatalf("expected error <%s>, got <%s>", writerError, err)
+	if err := encoder.Encode(receiver); err != errWriter {
+		t.Fatalf("expected error <%s>, got <%s>", errWriter, err)
 	}
 
 }

internal/cnf/parser/nginx/errors.go

@@ -2,7 +2,7 @@ package nginx
 
 import (
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/clifmt"
+	"git.xdrm.io/go/nix-amer/internal/clifmt"
 )
 
 // ErrNullReceiver is raised when a null receiver is provided

internal/instruction/alias.go

@@ -39,3 +39,7 @@ func (d alias) Exec(ctx ExecutionContext) ([]byte, error) {
 	ctx.Alias[d.Name] = d.Value
 	return nil, nil
 }
+
+func (d alias) DryRun(ctx ExecutionContext) ([]byte, error) {
+	return d.Exec(ctx)
+}

internal/instruction/common.go

@@ -2,9 +2,9 @@ package instruction
 
 import (
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
-	"github.com/xdrm-brackets/nix-amer/internal/pkg"
-	"github.com/xdrm-brackets/nix-amer/internal/ser"
+	"git.xdrm.io/go/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/pkg"
+	"git.xdrm.io/go/nix-amer/internal/ser"
 )
 
 // T is the instruction common interface
@@ -15,6 +15,8 @@ type T interface {
 	Build(string) error
 	// Exec the given instruction
 	Exec(ExecutionContext) ([]byte, error)
+	// DryRun checks the success of the given instruction without actually running it (non-destructive)
+	DryRun(ExecutionContext) ([]byte, error)
 }
 
 // ExecutionContext contains system-specific drivers to manage the host

internal/instruction/copy.go

@@ -1,7 +1,6 @@
 package instruction
 
 import (
-	"fmt"
 	"os"
 	"strings"
 )
@@ -17,7 +16,7 @@ func (d *copy) Raw() string { return strings.Join([]string{"copy", d.raw}, " ")
 func (d *copy) Build(_args string) error {
 
 	// 1. extract action (sub command)
-	split := strings.Split(_args, " ")
+	split := strings.Fields(_args)
 
 	// 2. check syntax
 	if len(split) != 2 {
@@ -34,14 +33,52 @@ func (d copy) Exec(ctx ExecutionContext) ([]byte, error) {
 
 	// 1. fail if source file not found
 	if _, err := os.Stat(d.Src); os.IsNotExist(err) {
-		return nil, fmt.Errorf("cannot find script '%s'", d.Src)
+		return nil, &FileError{"cannot find file", d.Src, err}
 	}
 
 	// 2. execute script
-	if err := ctx.Executor.Command("cp", d.Src, d.Dst).Run(); err != nil {
-		return nil, fmt.Errorf("cannot copy '%s' to '%s' | %s", d.Src, d.Dst, err)
+	if err := ctx.Executor.Command("cp", "-r", d.Src, d.Dst).Run(); err != nil {
+		return nil, &FileError{"cannot copy to", d.Dst, err}
 	}
 
 	return nil, nil
 
 }
+
+func (d copy) DryRun(ctx ExecutionContext) ([]byte, error) {
+
+	// 1. fail if source file not found
+	if _, err := os.Stat(d.Src); os.IsNotExist(err) {
+		return nil, &FileError{"cannot find file", d.Src, err}
+	}
+
+	// 2. if destination to create : try to create (then remove)
+	fi, err := os.Stat(d.Dst)
+	if os.IsNotExist(err) {
+
+		file, err2 := os.OpenFile(d.Dst, os.O_APPEND|os.O_WRONLY|os.O_CREATE, os.FileMode(0777))
+		if err2 != nil {
+			return nil, &FileError{"cannot copy to", d.Dst, err2}
+		}
+		file.Close()
+
+		if err2 := os.Remove(d.Dst); err2 != nil {
+			return nil, &FileError{"cannot remove dry-run file", d.Dst, err2}
+		}
+
+		return nil, nil
+
+	} else if fi != nil && fi.IsDir() {
+		return nil, nil // no error if dir
+	}
+
+	// 3. if destination exists : check write permission
+	file, err := os.OpenFile(d.Dst, os.O_APPEND|os.O_WRONLY, 0600)
+	if err != nil {
+		return nil, &FileError{"cannot copy to", d.Dst, err}
+	}
+	file.Close()
+
+	return nil, nil
+
+}

internal/instruction/copy_test.go

@@ -0,0 +1,308 @@
+package instruction
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+func TestCopyInvalidSyntax(t *testing.T) {
+	tests := []string{
+		"one-arg",
+		"src dst extra-arg",
+	}
+
+	for i, test := range tests {
+		inst := new(copy)
+		err := inst.Build(test)
+		if err != ErrInvalidSyntax {
+			t.Errorf("[%d] expected error <%s>, got <%s>", i, ErrInvalidSyntax, err)
+		}
+	}
+}
+func TestCopyBuildArgs(t *testing.T) {
+	tests := []string{
+		"source destination",
+		"\tsource destination",
+		" source destination",
+		"source\t destination",
+		"source  destination",
+		"source \tdestination",
+		"source  destination",
+		"source  destination\t",
+		"source\t\tdestination\t",
+		"source \t\t destination\t",
+		"source\t  \tdestination\t",
+	}
+
+	for i, test := range tests {
+		inst := new(copy)
+		err := inst.Build(test)
+		if err != nil {
+			t.Errorf("[%d] unexpected error <%s>", i, err)
+			continue
+		}
+
+		if inst.Src != "source" {
+			t.Errorf("[%d] expected 'source', got '%s'", i, inst.Src)
+			continue
+		}
+		if inst.Dst != "destination" {
+			t.Errorf("[%d] expected 'source', got '%s'", i, inst.Dst)
+			continue
+		}
+
+	}
+}
+
+func TestCopySourceNotExist(t *testing.T) {
+	defer os.RemoveAll("/tmp/destination")
+	raw := "/tmp/source /tmp/destination"
+
+	ctx, err := CreateContext("apt-get", "")
+	if err != nil {
+		t.Fatalf("cannot create context")
+	}
+
+	for i := 0; i < 2; i++ {
+		inst := new(copy)
+		err := inst.Build(raw)
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+		if i == 0 {
+			_, err = inst.Exec(*ctx)
+		} else {
+			_, err = inst.DryRun(*ctx)
+		}
+		if err == nil {
+			t.Fatalf("[%d] expected error", i)
+		}
+
+		ce, ok := err.(*FileError)
+		if !ok {
+			t.Fatalf("[%d] expected error of type <*FileError>", i)
+		}
+		if ce.Reason != "cannot find file" || ce.File != "/tmp/source" {
+			t.Fatalf("[%d] expected error <%s '%s'> got <%s '%s'>", i, "cannot find file", "/tmp/source", ce.Reason, ce.File)
+		}
+	}
+}
+
+func TestCopySourceIsDir(t *testing.T) {
+	src, dst := "/tmp/sourcedir", "/tmp/destinationdir"
+	raw := fmt.Sprintf("%s %s", src, dst)
+	defer os.RemoveAll(src)
+	defer os.RemoveAll(dst)
+
+	ctx, err := CreateContext("apt-get", "")
+	if err != nil {
+		t.Fatalf("cannot create context")
+	}
+
+	for i := 0; i < 2; i++ {
+		// 1. create directory
+		os.RemoveAll(src)
+		if err := os.MkdirAll(src, os.FileMode(0777)); err != nil {
+			t.Fatalf("[%d] cannot create test directory | %s", i, err)
+		}
+
+		inst := new(copy)
+		err := inst.Build(raw)
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+		if i == 0 {
+			_, err = inst.Exec(*ctx)
+		} else {
+			_, err = inst.DryRun(*ctx)
+		}
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+	}
+
+}
+func TestCopyInvalidDestination(t *testing.T) {
+	src, dst := "/tmp/source", "/tmp/missing-directory/invalid-destination"
+	raw := fmt.Sprintf("%s %s", src, dst)
+	defer os.RemoveAll(src)
+	defer os.RemoveAll(dst)
+
+	ctx, err := CreateContext("apt-get", "")
+	if err != nil {
+		t.Fatalf("cannot create context")
+	}
+
+	for i := 0; i < 2; i++ {
+
+		os.RemoveAll(src)
+		// 1. create directory
+		if err := os.MkdirAll(src, os.FileMode(0777)); err != nil {
+			t.Fatalf("[%d] cannot create test directory | %s", i, err)
+		}
+		inst := new(copy)
+		err := inst.Build(raw)
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+		if i == 0 {
+			_, err = inst.Exec(*ctx)
+		} else {
+			_, err = inst.DryRun(*ctx)
+		}
+		if err == nil {
+			t.Fatalf("[%d] expected error", i)
+		}
+
+		ce, ok := err.(*FileError)
+		if !ok {
+			t.Fatalf("[%d] expected error of type <*FileError>", i)
+		}
+		if ce.Reason != "cannot copy to" || ce.File != dst {
+			t.Fatalf("[%d] expected error <%s '%s'> got <%s '%s'>", i, "cannot copy to", dst, ce.Reason, ce.File)
+		}
+
+	}
+}
+func TestCopySourceIsFile(t *testing.T) {
+	src, dst := "/tmp/source", "/tmp/destination-file"
+	raw := fmt.Sprintf("%s %s", src, dst)
+	defer os.RemoveAll(src)
+	defer os.RemoveAll(dst)
+
+	ctx, err := CreateContext("apt-get", "")
+	if err != nil {
+		t.Fatalf("cannot create context")
+	}
+
+	for i := 0; i < 2; i++ {
+
+		os.RemoveAll(src)
+
+		// 1. create directory
+		fd, err := os.Create(src)
+		if err != nil {
+			t.Fatalf("[%d] cannot create test file | %s", i, err)
+		}
+		fd.Close()
+
+		inst := new(copy)
+		err = inst.Build(raw)
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+		if i == 0 {
+			_, err = inst.Exec(*ctx)
+		} else {
+			_, err = inst.DryRun(*ctx)
+		}
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+	}
+}
+
+func TestCopySourceIsFileDestinationExists(t *testing.T) {
+	src, dst := "/tmp/source", "/tmp/destination-file"
+	raw := fmt.Sprintf("%s %s", src, dst)
+	defer os.RemoveAll(src)
+	defer os.RemoveAll(dst)
+
+	ctx, err := CreateContext("apt-get", "")
+	if err != nil {
+		t.Fatalf("cannot create context")
+	}
+
+	for i := 0; i < 2; i++ {
+
+		os.RemoveAll(src)
+		os.RemoveAll(dst)
+
+		// 1. create source
+		fd, err := os.Create(src)
+		if err != nil {
+			t.Fatalf("[%d] cannot create test file | %s", i, err)
+		}
+		fd.Close()
+		// 1. create destination
+		fd, err = os.Create(src)
+		if err != nil {
+			t.Fatalf("[%d] cannot create test file | %s", i, err)
+		}
+		fd.Close()
+
+		inst := new(copy)
+		err = inst.Build(raw)
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+		if i == 0 {
+			_, err = inst.Exec(*ctx)
+		} else {
+			_, err = inst.DryRun(*ctx)
+		}
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+	}
+}
+func TestCopyCannotWriteDestination(t *testing.T) {
+	src, dst := "/tmp/source", "/tmp/destination-perm"
+	raw := fmt.Sprintf("%s %s", src, dst)
+	defer os.RemoveAll(src)
+	defer os.RemoveAll(dst)
+
+	ctx, err := CreateContext("apt-get", "")
+	if err != nil {
+		t.Fatalf("cannot create context")
+	}
+
+	for i := 0; i < 2; i++ {
+
+		os.RemoveAll(src)
+		if err := os.RemoveAll(dst); err != nil {
+			t.Fatalf("[%d] cannot remove destination file\n", i)
+		}
+
+		// 1. create source
+		fd, err := os.Create(src)
+		if err != nil {
+			t.Fatalf("[%d] cannot create test file | %s", i, err)
+		}
+		fd.Close()
+		// 1. create destination
+		fd, err = os.Create(src)
+		if err != nil {
+			t.Fatalf("[%d] cannot create test file | %s", i, err)
+		}
+		err = fd.Chmod(os.FileMode(0555))
+		if err != nil {
+			t.Fatalf("[%d] cannot set permissions | %s", i, err)
+		}
+		fd.Close()
+
+		inst := new(copy)
+		err = inst.Build(raw)
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+		if i == 0 {
+			_, err = inst.Exec(*ctx)
+		} else {
+			_, err = inst.DryRun(*ctx)
+		}
+		if err != nil {
+			t.Fatalf("[%d] unexpected error <%s>", i, err)
+		}
+
+	}
+}

internal/instruction/delete.go

@@ -33,3 +33,7 @@ func (d delete) Exec(ctx ExecutionContext) ([]byte, error) {
 	return nil, nil
 
 }
+
+func (d delete) DryRun(ctx ExecutionContext) ([]byte, error) {
+	return nil, nil
+}

internal/instruction/errors.go

@@ -1,15 +1,29 @@
 package instruction
 
 import (
-	"errors"
+	"fmt"
 )
 
 // ErrInvalidAlias is raised when encountering an invalid token in an alias name
-var ErrInvalidAlias = errors.New("invalid alias name (contains '/')")
+var ErrInvalidAlias = fmt.Errorf("invalid alias name (contains '/')")
 
 // ErrInvalidSyntax is raised when encountering an invalid token
-var ErrInvalidSyntax = errors.New("invalid instruction format")
+var ErrInvalidSyntax = fmt.Errorf("invalid instruction format")
 
 // ErrUnknownInstruction is raised when encountering an unknown instruction
 // it can mean that you're not using the right version or that you've misspelled it
-var ErrUnknownInstruction = errors.New("unknown instruction")
+var ErrUnknownInstruction = fmt.Errorf("unknown instruction")
+
+// FileError is used for file-specific errors
+type FileError struct {
+	Reason string
+	File   string
+	Err    error
+}
+
+func (ce FileError) Error() string {
+	if ce.Err == nil {
+		return fmt.Sprintf("%s '%s'", ce.Reason, ce.File)
+	}
+	return fmt.Sprintf("%s '%s' | %s", ce.Reason, ce.File, ce.Err)
+}

internal/instruction/install.go

@@ -33,3 +33,7 @@ func (d install) Exec(ctx ExecutionContext) ([]byte, error) {
 	return nil, nil
 
 }
+
+func (d install) DryRun(ctx ExecutionContext) ([]byte, error) {
+	return nil, nil
+}

internal/instruction/run.go

@@ -40,3 +40,21 @@ func (d run) Exec(ctx ExecutionContext) ([]byte, error) {
 	return nil, nil
 
 }
+func (d run) DryRun(ctx ExecutionContext) ([]byte, error) {
+
+	// 1. get file / alias
+	path := d.raw
+	if !strings.Contains(path, "/") {
+		if p, exists := ctx.Alias[path]; exists {
+			path = p
+		}
+	}
+
+	// 1. fail if file not found
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return nil, fmt.Errorf("cannot find script '%s'", path)
+	}
+
+	return nil, nil
+
+}

internal/instruction/service.go

@@ -60,3 +60,17 @@ func (d service) Exec(ctx ExecutionContext) ([]byte, error) {
 	return nil, nil
 
 }
+func (d service) DryRun(ctx ExecutionContext) ([]byte, error) {
+
+	// fail if a service does not exist
+	for _, service := range d.Services {
+
+		if err := ctx.ServiceManager.Exec("status", service); err != nil {
+			return nil, fmt.Errorf("cannot find service '%s' | %s", service, err)
+		}
+
+	}
+
+	return nil, nil
+
+}

internal/instruction/set.go

@@ -2,8 +2,9 @@ package instruction
 
 import (
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/cnf"
+	"git.xdrm.io/go/nix-amer/internal/cnf"
 	"os"
+	"path/filepath"
 	"strings"
 )
 
@@ -94,3 +95,57 @@ func (d set) Exec(ctx ExecutionContext) ([]byte, error) {
 	return nil, nil
 
 }
+func (d set) DryRun(ctx ExecutionContext) ([]byte, error) {
+
+	// 1. get file / alias
+	path := d.File
+	if !strings.Contains(path, "/") {
+		if p, exists := ctx.Alias[path]; exists {
+			path = p
+		}
+	}
+
+	// 2. fail if file not found
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return nil, fmt.Errorf("cannot find file '%s'", path)
+	}
+
+	// 3. try to load format
+	format, err := cnf.Load(path)
+	if err != nil {
+		return nil, err
+	}
+
+	// 4. try to update value
+	if !format.Set(d.Path, d.Value) {
+		return nil, ErrCannotSet
+	}
+
+	// 5. fail on missing write permission
+	file, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY, os.FileMode(0775))
+	if err != nil {
+		return nil, fmt.Errorf("cannot update '%s' | %s", path, err)
+	}
+	file.Close()
+
+	// 6. create non-destructive dry-run folder
+	dryRunFolder := "/tmp/dry-run"
+	if err := os.MkdirAll(dryRunFolder, os.FileMode(0777)); err != nil {
+		return nil, fmt.Errorf("cannot create dry-run folder | %s", err)
+
+	}
+
+	// 7. create updated file inside .dry-run
+	tmpout := filepath.Join(dryRunFolder, strings.Replace(path, "/", "-", -1))
+	file, err = os.Create(tmpout)
+	if err != nil {
+		return nil, fmt.Errorf("cannot create dry-run file '%s' | %s", tmpout, err)
+	}
+	defer file.Close()
+	if _, err = format.WriteTo(file); err != nil {
+		return nil, fmt.Errorf("cannot write dry-run file '%s' | %s", tmpout, err)
+	}
+
+	return nil, nil
+
+}

internal/pkg/apk.go

@@ -1,6 +1,6 @@
 package pkg
 
-import "github.com/xdrm-brackets/nix-amer/internal/exec"
+import "git.xdrm.io/go/nix-amer/internal/exec"
 
 type apk struct{ exec exec.Executor }
 

internal/pkg/apt.go

@@ -1,7 +1,7 @@
 package pkg
 
 import (
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 )
 
 type aptGet struct{ exec exec.Executor }

internal/pkg/common.go

@@ -1,7 +1,7 @@
 package pkg
 
 import (
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 )
 
 // DefaultManager if not empty is the default package-manager to use when missing

internal/pkg/dnf.go

@@ -1,6 +1,6 @@
 package pkg
 
-import "github.com/xdrm-brackets/nix-amer/internal/exec"
+import "git.xdrm.io/go/nix-amer/internal/exec"
 
 type dnf struct{ exec exec.Executor }
 

internal/pkg/eopkg.go

@@ -1,6 +1,6 @@
 package pkg
 
-import "github.com/xdrm-brackets/nix-amer/internal/exec"
+import "git.xdrm.io/go/nix-amer/internal/exec"
 
 type eopkg struct{ exec exec.Executor }
 

internal/pkg/loader.go

@@ -2,7 +2,7 @@ package pkg
 
 import (
 	"errors"
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 )
 
 // ErrUnknownManager is raised when the asked manager does not exist

internal/pkg/loader_test.go

@@ -1,7 +1,7 @@
 package pkg
 
 import (
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 	"testing"
 )
 

internal/pkg/pacman.go

@@ -1,6 +1,6 @@
 package pkg
 
-import "github.com/xdrm-brackets/nix-amer/internal/exec"
+import "git.xdrm.io/go/nix-amer/internal/exec"
 
 type pacman struct{ exec exec.Executor }
 

internal/pkg/yum.go

@@ -1,6 +1,6 @@
 package pkg
 
-import "github.com/xdrm-brackets/nix-amer/internal/exec"
+import "git.xdrm.io/go/nix-amer/internal/exec"
 
 type yum struct{ exec exec.Executor }
 

internal/ser/common.go

@@ -1,7 +1,7 @@
 package ser
 
 import (
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 )
 
 // DefaultManager if not empty is the default service-manager to use when missing

internal/ser/loader.go

@@ -2,7 +2,7 @@ package ser
 
 import (
 	"errors"
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 )
 
 // ErrUnknownManager is raised when the asked manager does not exist

internal/ser/systemd.go

@@ -1,13 +1,13 @@
 package ser
 
 import (
-	"github.com/xdrm-brackets/nix-amer/internal/exec"
+	"git.xdrm.io/go/nix-amer/internal/exec"
 )
 
 type systemd struct{ exec exec.Executor }
 
 // available actions
-var actions = []string{"enable", "disable", "start", "stop", "reload", "restart"}
+var actions = []string{"enable", "disable", "status", "start", "stop", "reload", "restart"}
 
 func (d *systemd) SetExecutor(_exec exec.Executor) {
 	d.exec = _exec

main.go

@@ -2,8 +2,8 @@ package main
 
 import (
 	"fmt"
-	"github.com/xdrm-brackets/nix-amer/internal/buildfile"
-	"github.com/xdrm-brackets/nix-amer/internal/clifmt"
+	"git.xdrm.io/go/nix-amer/internal/buildfile"
+	"git.xdrm.io/go/nix-amer/internal/clifmt"
 	"os"
 	"time"
 )
@@ -30,7 +30,12 @@ func main() {
 	// 2. parse buildfile
 	instructions, err := buildfile.NewReader(ctx, bfreader)
 	if err != nil {
-		fmt.Printf("%s%s\n", bf, err)
+		if _, ok := err.(buildfile.LineError); ok {
+			fmt.Printf("line error\n")
+			fmt.Printf("%s%s\n", bf, err.Error())
+		} else {
+			fmt.Printf("%s\n", clifmt.Warn(err.Error()))
+		}
 		return
 	}
 
@@ -38,13 +43,10 @@ func main() {
 	fmt.Printf("%s\n", clifmt.Color(32, "valid"))
 
 	// stop here if dry run
-	if dryRun {
-		return
-	}
 
 	// 3. Execute
 	fmt.Printf("------\n")
-	err = instructions.Execute()
+	err = instructions.Execute(dryRun)
 	if err != nil {
 		fmt.Printf("%s\n", clifmt.Warn(err.Error()))
 		return
@@ -53,4 +55,8 @@ func main() {
 	clifmt.Align("finished in")
 	fmt.Printf("%ss\n", clifmt.Color(32, fmt.Sprintf("%.2f", time.Now().Sub(start).Seconds())))
 
+	if dryRun {
+		fmt.Printf("\n%s %s\n", clifmt.Info("updated configurations are inside"), clifmt.Color(32, "/tmp/dry-run"))
+	}
+
 }