Remove unused test, add documentation

Signed-off-by: Mathis Joffre <[email protected]>

README.md

@@ -1,6 +1,6 @@
-# Open Policy Agent Gin Middleware
+# Open Policy Agent Middleware
 
-This middleware integrates Open Policy Agent (OPA) to your gin app.
+This middleware integrates Open Policy Agent (OPA) to your http/gin/fiber app.
 You can use it to enforce policies on endpoints.
 You can use OPA as local policy engine, or as a remote policy engine.
 
@@ -10,75 +10,202 @@ You can use OPA as local policy engine, or as a remote policy engine.
 go get github.com/Joffref/opa-middleware
 ```
 
-## Usage
-### Local policy engine
+## Usage Generic with OPA and HTTP
+
+### Local based policy engine
+
 ```go
 package main
 
 import (
-    "github.com/Joffref/gin-opa-middleware"
-    "github.com/gin-gonic/gin"
+	"github.com/Joffref/opa-middleware/config"
+	"github.com/Joffref/opa-middleware/middleware/http"
+	"net/http"
 )
 
-var policy = `
-package example.authz
+var Policy = `
+package policy
 
-default allow := false
+default allow = false
 
 allow {
-	input.method == "GET"
+	input.path = "/api/v1/users"
+	input.method = "GET"
 }`
 
+type H struct {
+	Name string
+}
+
+func (h *H) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte("Hello World : " + h.Name))
+}
+
 func main() {
-    r := gin.Default()
-	r.Use(opa.Middleware(context.Background(), &opa.Config{
-		Policy: policy,
-		Query: "data.example.authz.allow",
-		InputCreationMethod: func(c *gin.Context) (map[string]interface{}, error) {
-			return map[string]interface{}{
-				"method": c.Request.Method,
-			}, nil
+	handler, err := httpmiddleware.NewHTTPMiddleware(
+		&config.Config{
+			Policy: Policy,
+			Query:  "data.policy.allow",
+			InputCreationMethod: func(r *http.Request) (map[string]interface{}, error) {
+				return map[string]interface{}{
+					"path":   r.URL.Path,
+					"method": r.Method,
+				}, nil
+			},
+			ExceptedResult:   true,
+			DeniedStatusCode: 403,
+			DeniedMessage:    "Forbidden",
 		},
-		ExceptedResult:   true,
-		DeniedStatusCode: 403,
-		Debug:            true,
-		Logger:           log.New(gin.DefaultWriter, "[opa] ", log.LstdFlags),
-	}))
-    r.GET("/", func(c *gin.Context) {
-        c.String(200, "Hello World!")
-    })
-    r.Run()
+		&H{
+			Name: "John Doe",
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+	err = http.ListenAndServe(":8080", handler)
+	if err != nil {
+		return
+	}
+}
+```
+
+### Remote based policy engine
+
+```go
+package main
+
+import (
+	"github.com/Joffref/opa-middleware/config"
+	"github.com/Joffref/opa-middleware/middleware/http"
+	"net/http"
+)
+
+type H struct {
+	Name string
+}
+
+func (h *H) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte("Hello World : " + h.Name))
+}
+
+func main() {
+	handler, err := httpmiddleware.NewHTTPMiddleware(
+		&config.Config{
+			URL:   "http://localhost:8181",
+			Query: "data.policy.allow",
+			InputCreationMethod: func(r *http.Request) (map[string]interface{}, error) {
+				return map[string]interface{}{
+					"path":   r.URL.Path,
+					"method": r.Method,
+				}, nil
+			},
+			ExceptedResult:   true,
+			DeniedStatusCode: 403,
+			DeniedMessage:    "Forbidden",
+		},
+		&H{
+			Name: "John Doe",
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+	err = http.ListenAndServe(":8080", handler)
+	if err != nil {
+		return
+	}
 }
 ```
-### Remote policy engine
+
+## Usage with GIN
 ```go
 package main
 
 import (
-    "github.com/Joffref/gin-opa-middleware"
+    "github.com/Joffref/opa-middleware/config"
+    ginmiddleware "github.com/Joffref/opa-middleware/middleware/gin"
     "github.com/gin-gonic/gin"
 )
+
 func main() {
     r := gin.Default()
-    r.Use(opa.Middleware(context.Background(), &opa.Config{
-        URL:   "http://localhost:8181",
-        Query: "data.example.authz.allow",
-        InputCreationMethod: func(c *gin.Context) (map[string]interface{}, error) {
-        return map[string]interface{}{
-        "method": c.Request.Method,
-        }, nil
-        },
-        ExceptedResult:   true,
-        DeniedStatusCode: 403,
-        Debug:            true,
-        Logger:           log.New(gin.DefaultWriter, "[opa] ", log.LstdFlags),
-    }))
-    r.GET("/", func(c *gin.Context) {
-        c.String(200, "Hello World!")
+    r.GET("/ping", func(c *gin.Context) {
+        c.JSON(200, gin.H{
+            "message": "pong",
+        })
     })
-    err := r.Run(":8080")
+    middleware, err := ginmiddleware.NewGinMiddleware(
+        &config.Config{
+            URL:   "https://opa.example.com/",
+            Query: "data.policy.allow",
+        },
+        func(c *gin.Context) (map[string]interface{}, error) {
+            return map[string]interface{}{
+                "path":   c.Request.URL.Path,
+                "method": c.Request.Method,
+            }, nil
+    },
+    )
     if err != nil {
-		return
+        return
     }
+    r.Use(middleware.Use())
+    err = r.Run(":8080")
+    if err != nil {
+        return
+    }
+}
+```
+
+## Usage with Fiber
+```go
+package main
+
+import (
+	"github.com/Joffref/opa-middleware/config"
+	fibermiddleware "github.com/Joffref/opa-middleware/middleware/fiber"
+	"github.com/gofiber/fiber/v2"
+	"log"
+	"time"
+)
+
+func main() {
+	app := fiber.New()
+	app.Get("/", func(c *fiber.Ctx) error {
+		return c.SendString("Hello World!")
+	})
+
+	middleware, err := fibermiddleware.NewFiberMiddleware(&config.Config{
+		URL:              "http://localhost:8080/",
+		Query:            "data.policy.allow",
+		DeniedStatusCode: 403,
+		DeniedMessage:    "Forbidden",
+		Headers: map[string]string{
+			"Content-Type": "application/json",
+		},
+		IgnoredHeaders: []string{
+			"X-Request-Id",
+		},
+		Debug:          true,
+		Logger:         log.New(log.Writer(), "", log.LstdFlags),
+		ExceptedResult: true,
+		Timeout:        5 * time.Second,
+	},
+		func(c *fiber.Ctx) (map[string]interface{}, error) {
+			return map[string]interface{}{
+				"path":   c.Path(),
+				"method": c.Method(),
+			}, nil
+		},
+	)
+	if err != nil {
+		return
+	}
+	app.Use(middleware.Use())
+	err = app.Listen(":3000")
+	if err != nil {
+		return
+	}
 }
 ```