From c51281c7310aa21ec2da7cd9854f95219091a53b Mon Sep 17 00:00:00 2001
From: xdrm-brackets <xdrm.brackets.dev@gmail.com>
Date: Sat, 29 Sep 2018 17:01:58 +0200
Subject: [PATCH] create import driver (not finished)

---
 driver/import.go | 113 +++++++++++++++++++++++++++++++++++++++++++++++
 driver/types.go  |  40 +++++++++++++++++
 2 files changed, 153 insertions(+)
 create mode 100644 driver/import.go

diff --git a/driver/import.go b/driver/import.go
new file mode 100644
index 0000000..f8b715c
--- /dev/null
+++ b/driver/import.go
@@ -0,0 +1,113 @@
+package driver
+
+import (
+	"errors"
+	"fmt"
+	e "git.xdrm.io/go/aicra/err"
+	"git.xdrm.io/go/aicra/response"
+	"net/http"
+	"plugin"
+	"strings"
+)
+
+// Name returns the driver name
+func (d *Import) Name() string { return "import" }
+
+// RegisterController registers a new controller
+func (d *Import) RegisterController(_path string, _controller Controller) error {
+
+	// 1. init controllers if not already
+	if d.Controllers == nil {
+		d.Controllers = make(map[string]Controller)
+	}
+
+	// 2. fail if no controller
+	if _controller == nil {
+		return errors.New("nil controller")
+	}
+
+	// 3. Fail on invalid path
+	if len(_path) < 1 || _path[0] != '/' {
+		return errors.New("invalid controller path")
+	}
+
+	// 4. Store controller
+	d.Controllers[_path] = _controller
+	return nil
+
+}
+
+// RegisterMiddleware registers a new controller
+func (d *Import) RegisterMiddlware(_path string, _middleware Middleware) error {
+
+	// 1. init imddlewares if not already
+	if d.Middlewares == nil {
+		d.Middlewares = make(map[string]Middleware)
+	}
+
+	// 2. fail if no imddleware
+	if _middleware == nil {
+		return errors.New("nil imddleware")
+	}
+
+	// 3. Fail on invalid path
+	if len(_path) < 1 || _path[0] != '/' {
+		return errors.New("invalid imddleware path")
+	}
+
+	// 4. Store imddleware
+	d.Middlewares[_path] = _middleware
+	return nil
+
+}
+
+// RunController implements the Driver interface
+func (d *Import) RunController(_path []string, _method string) (func(response.Arguments) response.Response, err.Error) {
+
+	/* (1) Build controller path */
+	path := strings.Join(_path, "-")
+
+	/* (2) Check if controller exists */
+	controller, ok := d.Controllers[path]
+	if !ok {
+		return nil, e.UncallableController
+	}
+
+	/* (3) Format method */
+	method := strings.ToLower(_method)
+
+	/* (4) Return method according to method */
+	switch method {
+	case "GET":
+		return controller.Get, e.Success
+	case "POST":
+		return controller.Post, e.Success
+	case "PUT":
+		return controller.Put, e.Success
+	case "DELETE":
+		return controller.Delete, e.Success
+	default:
+		return nil, e.UncallableMethod
+	}
+
+	return nil, e.UncallableController
+}
+
+// LoadMiddleware returns a new middleware function; it must be a
+// valid and existing folder/filename file with the .so extension
+func (d *Import) LoadMiddleware(_path string) (func(http.Request, *[]string), error) {
+
+	/* (1) Check plugin name */
+	if len(_path) < 1 {
+		return nil, errors.New("middleware name must not be empty")
+	}
+
+	/* (2) Check if middleware exists */
+	middleware, ok := d.Middlewares[_path]
+	if !ok {
+		return nil, errors.New("middleware not found")
+	}
+
+	/* (3) Return middleware */
+	return mware, nil
+}
diff --git a/driver/types.go b/driver/types.go
index 4212fd5..61aeb0a 100644
--- a/driver/types.go
+++ b/driver/types.go
@@ -25,6 +25,46 @@ type Driver interface {
 // - the a/b/c controller executable must be named <WORKDIR>/controller/a/b/c
 type Generic struct{}
 
+// Controller is the interface that controller implementation must follow
+// it is used by the 'Import' driver
+type Controller interface {
+	Get(d response.Arguments) response.Response
+	Post(d response.Arguments) response.Response
+	Put(d response.Arguments) response.Response
+	Delete(d response.Arguments) response.Response
+}
+
+// Middleware is the interface that middleware implementation must follow
+// it is used by the 'Import' driver
+type Middleware interface {
+	Inspect(http.Request, *[]string)
+}
+
+// Import tells the aicra instance to use the import driver to load controller/middleware executables
+//
+// It will compile imported with the following interface :
+//
+// type Controller interface {
+// 	Get(d response.Arguments) response.Response
+// 	Post(d response.Arguments) response.Response
+// 	Put(d response.Arguments) response.Response
+// 	Delete(d response.Arguments) response.Response
+// }
+//
+// CONTROLLER FILE STRUCTURE
+// --------------
+// - the root (/) controller executable must be named  <WORKDIR>/controller/ROOT.go
+// - the a/b/c controller executable must be named <WORKDIR>/controller/a/b/c.go
+//
+// COMPILATION
+// -----------
+// The controllers/middlewares are imported and instanciated inside the main function, they are
+// thus compiled with the main binary file
+type Import struct {
+	Controllers map[string]Controller
+	Middlewares map[string]Middleware
+}
+
 // Plugin tells the aicra instance to use the plugin driver to load controller/middleware executables
 //
 // It will load go .so plugins with the following interface :