From ff06cccb89f25f57db4ce1532ada4ebdbb328d1d Mon Sep 17 00:00:00 2001
From: xdrm-brackets <doowap31@gmail.com>
Date: Sat, 10 Nov 2018 12:37:31 +0100
Subject: [PATCH] udpdate main program | simplify loaders (no more meta table
 for distro/package) | add default loader (pkg, ser) values | manage context
 creation : instruction.CreateContext() | fix tests | no more -distro
 parameter, only -package

---
 cmd/nix-amer/args.go              | 55 +++++++++++++++++++++++
 cmd/nix-amer/help.go              |  7 +--
 cmd/nix-amer/main.go              | 34 +++++++++++++-
 internal/buildfile/errors.go      |  3 +-
 internal/buildfile/reader.go      | 28 +++++++++---
 internal/buildfile/reader_test.go |  4 +-
 internal/instruction/cnf.go       | 11 +++--
 internal/instruction/common.go    | 41 ++++++++++++++++-
 internal/instruction/reader.go    |  7 +--
 internal/pkg/common.go            |  2 +
 internal/pkg/loader.go            | 73 +++++++++----------------------
 internal/pkg/loader_test.go       | 37 +++-------------
 internal/ser/common.go            |  2 +
 internal/ser/loader.go            | 27 +++---------
 meta/pkg-drivers.json             | 13 ------
 15 files changed, 200 insertions(+), 144 deletions(-)
 create mode 100644 cmd/nix-amer/args.go
 delete mode 100644 meta/pkg-drivers.json

diff --git a/cmd/nix-amer/args.go b/cmd/nix-amer/args.go
new file mode 100644
index 0000000..29b9533
--- /dev/null
+++ b/cmd/nix-amer/args.go
@@ -0,0 +1,55 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"git.xdrm.io/xdrm-brackets/nix-amer/internal/instruction"
+)
+
+func GetArgs() (*instruction.ExecutionContext, string, error) {
+	setupFlags(flag.CommandLine)
+
+	longPack := flag.String("package", "", "")
+	longServ := flag.String("service", "", "")
+	pack := flag.String("p", "", "")
+	serv := flag.String("s", "", "")
+	flag.Parse()
+
+	// 1. fail on missing build file
+	if len(flag.Args()) < 1 {
+		return nil, "", fmt.Errorf("missing buildfile")
+	}
+	buildfile := flag.Arg(0)
+
+	// 2. override short version with long
+	if longPack != nil && len(*longPack) > 0 {
+		pack = longPack
+	}
+	if longServ != nil && len(*longServ) > 0 {
+		serv = longServ
+	}
+
+	// 3. fail on missing mandatory fields
+	if pack == nil || len(*pack) < 1 {
+		return nil, "", fmt.Errorf("missing -package")
+	}
+	// if serv == nil || len(*serv) < 1 { // default service
+	// 	return nil, "", fmt.Errorf("missing -service")
+	// }
+
+	// 3. Load context
+	ctx, err := instruction.CreateContext(*pack, *serv)
+	if err != nil {
+		return nil, "", err
+	}
+	/*DEBUG*/ //fmt.Printf("package: '%s' | '%s'\n", fpackage, lpackage)
+	/*DEBUG*/ //fmt.Printf("service: '%s' | '%s'\n", fservice, lservice)
+
+	return ctx, buildfile, nil
+}
+
+func setupFlags(f *flag.FlagSet) {
+	f.Usage = func() {
+		help()
+	}
+}
diff --git a/cmd/nix-amer/help.go b/cmd/nix-amer/help.go
index 73a0165..abb11f1 100644
--- a/cmd/nix-amer/help.go
+++ b/cmd/nix-amer/help.go
@@ -11,7 +11,7 @@ func help() {
 	fmt.Printf("\tnix-amer - the automatic setup tool you need\n")
 
 	fmt.Printf("\n%s\n", clifmt.Color(1, "SYNOPSIS", true))
-	fmt.Printf("\tnix-amer [-d  <linux-distro> [-p <package-manager>] [-s <service-manager>] <buildfile>\n")
+	fmt.Printf("\tnix-amer [-p <package-manager>] [-s <service-manager>] <buildfile>\n")
 	fmt.Printf("\tnix-amer -help\n")
 	fmt.Printf("\tnix-amer -h\n")
 	fmt.Printf("\n")
@@ -28,11 +28,6 @@ func help() {
 
 	fmt.Printf("\n%s\n", clifmt.Color(1, "OPTIONS", true))
 
-	fmt.Printf("\t-d, -distro\n\t    Define which linux distribution the target will run on.\n")
-	fmt.Printf("\t    Available values are 'debian', 'ubuntu', 'alpine', 'solus',\n")
-	fmt.Printf("\t    'arch', 'centos' and 'fedora'.\n")
-	fmt.Printf("\n")
-
 	fmt.Printf("\t-p, -package\n\t    Define which package manager to use ; normally it is\n")
 	fmt.Printf("\t    automatically guessed if you define the -distro. Available\n")
 	fmt.Printf("\t    values are 'apt-get', 'eopkg', 'apk', 'yum', 'dnf' and 'pacman'.\n")
diff --git a/cmd/nix-amer/main.go b/cmd/nix-amer/main.go
index 189984c..c99114d 100644
--- a/cmd/nix-amer/main.go
+++ b/cmd/nix-amer/main.go
@@ -1,5 +1,37 @@
 package main
 
+import (
+	"fmt"
+	"git.xdrm.io/xdrm-brackets/nix-amer/internal/buildfile"
+	"git.xdrm.io/xdrm-brackets/nix-amer/internal/clifmt"
+	"os"
+)
+
 func main() {
-	help()
+
+	// Manage arguments
+	ctx, bf, err := GetArgs()
+	if err != nil {
+		fmt.Printf("%s", err)
+		return
+	}
+
+	// 1. get buildfile reader
+	bfreader, err := os.Open(bf)
+	if err != nil {
+		fmt.Printf("cannot open buildfile | %s\n", err)
+		return
+	}
+	defer bfreader.Close()
+
+	// 2. parse buildfile
+	_, err = buildfile.NewReader(ctx, bfreader)
+	if err != nil {
+		fmt.Printf("%s%s\n", bf, err)
+		return
+	}
+
+	clifmt.Align("build file")
+	fmt.Printf("%s\n", clifmt.Color(32, "parsed"))
+
 }
diff --git a/internal/buildfile/errors.go b/internal/buildfile/errors.go
index d00ffdb..57adbd5 100644
--- a/internal/buildfile/errors.go
+++ b/internal/buildfile/errors.go
@@ -2,6 +2,7 @@ package buildfile
 
 import (
 	"fmt"
+	"git.xdrm.io/xdrm-brackets/nix-amer/internal/clifmt"
 )
 
 type LineError struct {
@@ -10,5 +11,5 @@ type LineError struct {
 }
 
 func (le LineError) Error() string {
-	return fmt.Sprintf("line %d | %s", le.Line, le.Err.Error())
+	return fmt.Sprintf(":%d %s", le.Line, clifmt.Color(31, le.Err.Error()))
 }
diff --git a/internal/buildfile/reader.go b/internal/buildfile/reader.go
index 2066758..b994790 100644
--- a/internal/buildfile/reader.go
+++ b/internal/buildfile/reader.go
@@ -2,23 +2,33 @@ package buildfile
 
 import (
 	"bufio"
+	"errors"
 	"git.xdrm.io/xdrm-brackets/nix-amer/internal/instruction"
 	"io"
+	"strings"
 )
 
+var ErrNullContext = errors.New("null context")
+
 // Reader is the buildfile reader
 type Reader struct {
-	// linux distribution to run on
-	distribution string
-	Content      []instruction.T
+	// Context is the linux distribution-specified execution context (package manager, service manager, etc)
+	Context *instruction.ExecutionContext
+	// Content is the instruction list
+	Content []instruction.T
 }
 
 // NewReader creates a new reader for the specified build file and linux distribution
-func NewReader(distro string, buildfile io.Reader) (*Reader, error) {
+func NewReader(ctx *instruction.ExecutionContext, buildfile io.Reader) (*Reader, error) {
+
+	// fail on null context
+	if ctx == nil {
+		return nil, ErrNullContext
+	}
 
 	r := &Reader{
-		distribution: distro,
-		Content:      make([]instruction.T, 0),
+		Context: ctx,
+		Content: make([]instruction.T, 0),
 	}
 
 	// add each line as instruction
@@ -33,6 +43,12 @@ func NewReader(distro string, buildfile io.Reader) (*Reader, error) {
 		} else if err != nil {
 			return nil, LineError{l, err}
 		}
+		line = strings.Trim(line, " \t\r\n")
+
+		// ignore newline & comments
+		if len(line) < 1 || line[0] == '[' {
+			continue
+		}
 
 		// turn into instruction
 		inst, err := instruction.Parse(line)
diff --git a/internal/buildfile/reader_test.go b/internal/buildfile/reader_test.go
index 3055977..03a8120 100644
--- a/internal/buildfile/reader_test.go
+++ b/internal/buildfile/reader_test.go
@@ -34,11 +34,13 @@ func TestInstructionSyntax(t *testing.T) {
 		{"ins args\ncm  args\n", 2, instruction.ErrInvalidSyntax},
 	}
 
+	ctx, _ := instruction.CreateContext("apt-get", "")
+
 	for i, test := range tests {
 
 		// create reader
 		buffer := bytes.NewBufferString(test.File)
-		_, err := NewReader("ubuntu", buffer)
+		_, err := NewReader(ctx, buffer)
 
 		// no error expected
 		if test.Err == nil {
diff --git a/internal/instruction/cnf.go b/internal/instruction/cnf.go
index 51facc6..fa46d07 100644
--- a/internal/instruction/cnf.go
+++ b/internal/instruction/cnf.go
@@ -2,6 +2,7 @@ package instruction
 
 import (
 	"fmt"
+	"git.xdrm.io/xdrm-brackets/nix-amer/internal/cnf"
 	"strings"
 )
 
@@ -12,20 +13,24 @@ type config struct {
 	Path []string
 	// Value if the value to add or update
 	Value string
+	// Format is the configuration format in use
+	Format *cnf.ConfigurationFormat
 }
 
 func (d *config) Build(_args string) error {
 
 	// 1. extract action (sub command)
-	split := strings.SplitN(_args, " ", 2)
+	split := strings.Fields(_args)
 
 	// 2. check path
 	if len(split) < 2 {
 		return fmt.Errorf("missing configuration path")
 	}
+	path := split[0]
+	value := strings.Join(split[1:], "")
 
 	// 3. check path separator
-	splitPath := strings.Split(split[0], "@")
+	splitPath := strings.Split(path, "@")
 	if len(splitPath) > 2 {
 		return fmt.Errorf("invalid path (additional '@'?)")
 	}
@@ -36,7 +41,7 @@ func (d *config) Build(_args string) error {
 	}
 
 	// add value
-	d.Value = split[1]
+	d.Value = value
 
 	return nil
 }
diff --git a/internal/instruction/common.go b/internal/instruction/common.go
index 66b383b..619739f 100644
--- a/internal/instruction/common.go
+++ b/internal/instruction/common.go
@@ -1,7 +1,7 @@
 package instruction
 
 import (
-	"git.xdrm.io/xdrm-brackets/nix-amer/internal/cnf"
+	"fmt"
 	"git.xdrm.io/xdrm-brackets/nix-amer/internal/pkg"
 	"git.xdrm.io/xdrm-brackets/nix-amer/internal/ser"
 )
@@ -16,6 +16,43 @@ type T interface {
 
 type ExecutionContext struct {
 	PackageManager pkg.PackageManager
-	Configuration  cnf.ConfigurationFormat
 	ServiceManager ser.ServiceManager
 }
+
+// CreateContext creates an execution contet with the given package-manager and service-manager
+// default values are taken from each go package (pkg, ser)
+func CreateContext(_pkg, _ser string) (*ExecutionContext, error) {
+
+	// 1. fail if no value and no defaults
+	if len(_pkg)+len(pkg.DefaultManager) < 1 {
+		return nil, fmt.Errorf("missing package manager")
+	}
+	if len(_ser)+len(ser.DefaultManager) < 1 {
+		return nil, fmt.Errorf("missing service manager")
+	}
+
+	// 2. set default
+	if len(_pkg) < 1 {
+		_pkg = pkg.DefaultManager
+	}
+	if len(_ser) < 1 {
+		_ser = ser.DefaultManager
+	}
+
+	// 3. load managers
+	pkg, err := pkg.Load(_pkg)
+	if err != nil {
+		return nil, fmt.Errorf("package manager: %s", err)
+	}
+	ser, err := ser.Load(_ser)
+	if err != nil {
+		return nil, fmt.Errorf("service manager: %s", err)
+	}
+
+	// 4. build context
+	return &ExecutionContext{
+		PackageManager: pkg,
+		ServiceManager: ser,
+	}, nil
+
+}
diff --git a/internal/instruction/reader.go b/internal/instruction/reader.go
index b3fc4ee..73f1fef 100644
--- a/internal/instruction/reader.go
+++ b/internal/instruction/reader.go
@@ -8,16 +8,15 @@ import (
 func Parse(raw string) (T, error) {
 
 	// 1. format (trim + split first space)
-	raw = strings.Trim(raw, " \t\n")
 	cmd := strings.SplitN(raw, " ", 2)
 	cmd[0] = strings.Trim(cmd[0], " \t")
-	cmd[1] = strings.Trim(cmd[1], " \t")
 
 	// 2. fail if invalid base syntax 'cmd args...'
 	// where command is 3 letters
 	if len(cmd) < 2 || len(cmd[0]) < 3 || cmd[0][1] == ' ' {
 		return nil, ErrInvalidSyntax
 	}
+	cmd[1] = strings.Trim(cmd[1], " \t")
 
 	// 3. Extract instruction type
 	switch cmd[0] {
@@ -29,10 +28,6 @@ func Parse(raw string) (T, error) {
 		i := &delete{}
 		err := i.Build(cmd[1])
 		return i, err
-	case "upd":
-		i := &update{}
-		err := i.Build(cmd[1])
-		return i, err
 	case "ser":
 		i := &service{}
 		err := i.Build(cmd[1])
diff --git a/internal/pkg/common.go b/internal/pkg/common.go
index f0c1615..00c86be 100644
--- a/internal/pkg/common.go
+++ b/internal/pkg/common.go
@@ -1,5 +1,7 @@
 package pkg
 
+var DefaultManager = ""
+
 // PackageManager is the common interface for all package-manager drivers (e.g. `dpkg` for debian-based, `pacman` for arch)
 type PackageManager interface {
 	// Name of executable (to check if installed and for debug)
diff --git a/internal/pkg/loader.go b/internal/pkg/loader.go
index bd36210..d15c24d 100644
--- a/internal/pkg/loader.go
+++ b/internal/pkg/loader.go
@@ -1,71 +1,38 @@
 package pkg
 
 import (
-	"encoding/json"
 	"errors"
-	"os"
-	"os/exec"
-	"path/filepath"
 )
 
-var ErrUnknownDistribution = errors.New("unknown linux distribution")
-var ErrNoCandidateInstalled = errors.New("no package-manager candidate installed")
-var ErrNoDriverFound = errors.New("no driver found for the package manager")
+var ErrUnknownManager = errors.New("unknown package manager")
+var ErrNotInstalled = errors.New("no candidate installed")
 
-func Load(_distro string) (PackageManager, error) {
+func Load(_manager string) (PackageManager, error) {
 
-	// 1. load config file
-	driverTable := filepath.Join(os.Getenv("GOPATH"), "src/git.xdrm.io/xdrm-brackets/nix-amer/meta/pkg-drivers.json")
-	file, err := os.Open(driverTable)
-	if err != nil {
-		return nil, err
-	}
-	defer file.Close()
-
-	// 2. Parse json
-	table := make(map[string][]string)
-	decoder := json.NewDecoder(file)
-	if err := decoder.Decode(&table); err != nil {
-		return nil, err
-	}
-	decoder = nil
-
-	// 3. Get available package-manager list for distro
-	available, exists := table[_distro]
-	if !exists || len(available) < 1 {
-		return nil, ErrUnknownDistribution
-	}
-
-	// 4. Check each available package-manager in order
-	selected := ""
-	for _, current := range available {
-		if exec.Command("which", current).Run() == nil {
-			selected = current
-			break
-		}
-	}
-
-	// no candidate installed
-	if len(selected) < 1 {
-		return nil, ErrNoCandidateInstalled
-	}
-
-	// 5. Instanciate
-	switch selected {
+	// 1. create manager (fail if unknown)
+	var manager PackageManager
+	switch _manager {
 	case "apt-get":
-		return new(Apt), nil
+		manager = new(Apt)
 	case "apk":
-		return new(Apk), nil
+		manager = new(Apk)
 	case "eopkg":
-		return new(Eopkg), nil
+		manager = new(Eopkg)
 	case "pacman":
-		return new(Pacman), nil
+		manager = new(Pacman)
 	case "dnf":
-		return new(Dnf), nil
+		manager = new(Dnf)
 	case "yum":
-		return new(Yum), nil
+		manager = new(Yum)
+	default:
+		return nil, ErrUnknownManager
 	}
 
-	return nil, ErrNoDriverFound
+	// 2. fail if not installed
+	// if exec.Command("which", manager.Name()).Run() != nil {
+	// 	return nil, ErrNotInstalled
+	// }
+
+	return manager, nil
 
 }
diff --git a/internal/pkg/loader_test.go b/internal/pkg/loader_test.go
index 9d6c26c..2c5fb82 100644
--- a/internal/pkg/loader_test.go
+++ b/internal/pkg/loader_test.go
@@ -1,46 +1,23 @@
 package pkg
 
 import (
-	"os/exec"
-	"strings"
 	"testing"
 )
 
-func TestUnknownDistribution(t *testing.T) {
+func TestUnknownManager(t *testing.T) {
 
-	_, err := Load("invalid-distro-xxx")
-	if err != ErrUnknownDistribution {
-		t.Errorf("expected <%s>, got <%s>", ErrUnknownDistribution, err)
+	_, err := Load("apt-put")
+	if err != ErrUnknownManager {
+		t.Errorf("expected <%s>, got <%s>", ErrUnknownManager, err)
 		t.Fail()
 	}
 
 }
-func TestNoCandidateInstalled(t *testing.T) {
+func TestKnownManager(t *testing.T) {
 
-	// get host distro
-	out, err := exec.Command("lsb_release", "-is").Output()
+	_, err := Load("apt-get")
 	if err != nil {
-		t.Errorf("cannot get host linux distribution")
-		t.Fail()
-	}
-	hostDistro := strings.ToLower(strings.Trim(string(out), " \n\t"))
-
-	// valid candidate
-	_, err = Load(hostDistro)
-	if err != nil {
-		t.Errorf("expected <nil>, got <%s>", err)
-		t.Fail()
-	}
-
-	// invalid candidate
-	distro := "solus"
-	if hostDistro == distro {
-		distro = "ubuntu"
-	}
-
-	_, err = Load(distro)
-	if err != ErrNoCandidateInstalled {
-		t.Errorf("expected <%s>, got <%s>", ErrNoCandidateInstalled, err)
+		t.Errorf("unexpected error <%s>", err)
 		t.Fail()
 	}
 
diff --git a/internal/ser/common.go b/internal/ser/common.go
index ff3465f..dfe1e72 100644
--- a/internal/ser/common.go
+++ b/internal/ser/common.go
@@ -1,5 +1,7 @@
 package ser
 
+var DefaultManager = "systemd"
+
 // ServiceManager is the common interface for service managers (systemd, init.d)
 type ServiceManager interface {
 	// Name of executable (to check if installed and for debug)
diff --git a/internal/ser/loader.go b/internal/ser/loader.go
index 4c35168..31636bb 100644
--- a/internal/ser/loader.go
+++ b/internal/ser/loader.go
@@ -2,31 +2,14 @@ package ser
 
 import (
 	"errors"
-	"os/exec"
 )
 
 var ErrUnknownManager = errors.New("unknown service manager")
-var ErrNoCandidateInstalled = errors.New("no package-manager candidate installed")
-
-// available service managers
-// var available = []string{"systemd", "init"}
-var available = []string{"systemd"}
+var ErrNotInstalled = errors.New("not candidate installed")
 
 func Load(_manager string) (ServiceManager, error) {
 
-	// 1. fail if unknown manager
-	known := false
-	for _, mgr := range available {
-		if _manager == mgr {
-			known = true
-			break
-		}
-	}
-	if !known {
-		return nil, ErrUnknownManager
-	}
-
-	// 2. Create manager accordingly
+	// 1. create manager (fail if unknown)
 	var manager ServiceManager
 	switch _manager {
 	case "systemd":
@@ -36,9 +19,9 @@ func Load(_manager string) (ServiceManager, error) {
 	}
 
 	// 2. fail if not installed
-	if exec.Command("which", manager.Name()).Run() == nil {
-		return nil, ErrNoCandidateInstalled
-	}
+	// if exec.Command("which", manager.Name()).Run() != nil {
+	// 	return nil, ErrNotInstalled
+	// }
 
 	return manager, nil
 
diff --git a/meta/pkg-drivers.json b/meta/pkg-drivers.json
deleted file mode 100644
index 956d76e..0000000
--- a/meta/pkg-drivers.json
+++ /dev/null
@@ -1,13 +0,0 @@
-{
-	"ubuntu": [ "apt-get"    ],
-	"debian": [ "apt-get"    ],
-
-	"alpine": [ "apk"        ],
-
-	"solus":  [ "eopkg"      ],
-
-	"arch":   [ "pacman"     ],
-
-	"centos": [ "dnf", "yum" ],
-	"fedora": [ "dnf", "yum" ]
-}
\ No newline at end of file