Refactor packages to have more idiomatic code base

http/handler/json_response.go

@@ -0,0 +1,111 @@
+// Copyright 2017 Frédéric Guillot. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+package handler
+
+import (
+	"encoding/json"
+	"errors"
+	"net/http"
+
+	"github.com/miniflux/miniflux/logger"
+)
+
+// JSONResponse handles JSON responses.
+type JSONResponse struct {
+	writer  http.ResponseWriter
+	request *http.Request
+}
+
+// Standard sends a JSON response with the status code 200.
+func (j *JSONResponse) Standard(v interface{}) {
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusOK)
+	j.writer.Write(j.toJSON(v))
+}
+
+// Created sends a JSON response with the status code 201.
+func (j *JSONResponse) Created(v interface{}) {
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusCreated)
+	j.writer.Write(j.toJSON(v))
+}
+
+// NoContent sends a JSON response with the status code 204.
+func (j *JSONResponse) NoContent() {
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusNoContent)
+}
+
+// BadRequest sends a JSON response with the status code 400.
+func (j *JSONResponse) BadRequest(err error) {
+	logger.Error("[Bad Request] %v", err)
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusBadRequest)
+
+	if err != nil {
+		j.writer.Write(j.encodeError(err))
+	}
+}
+
+// NotFound sends a JSON response with the status code 404.
+func (j *JSONResponse) NotFound(err error) {
+	logger.Error("[Not Found] %v", err)
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusNotFound)
+	j.writer.Write(j.encodeError(err))
+}
+
+// ServerError sends a JSON response with the status code 500.
+func (j *JSONResponse) ServerError(err error) {
+	logger.Error("[Internal Server Error] %v", err)
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusInternalServerError)
+
+	if err != nil {
+		j.writer.Write(j.encodeError(err))
+	}
+}
+
+// Forbidden sends a JSON response with the status code 403.
+func (j *JSONResponse) Forbidden() {
+	logger.Info("[API:Forbidden]")
+	j.commonHeaders()
+	j.writer.WriteHeader(http.StatusForbidden)
+	j.writer.Write(j.encodeError(errors.New("Access Forbidden")))
+}
+
+func (j *JSONResponse) commonHeaders() {
+	j.writer.Header().Set("Accept", "application/json")
+	j.writer.Header().Set("Content-Type", "application/json; charset=utf-8")
+}
+
+func (j *JSONResponse) encodeError(err error) []byte {
+	type errorMsg struct {
+		ErrorMessage string `json:"error_message"`
+	}
+
+	tmp := errorMsg{ErrorMessage: err.Error()}
+	data, err := json.Marshal(tmp)
+	if err != nil {
+		logger.Error("encoding error: %v", err)
+	}
+
+	return data
+}
+
+func (j *JSONResponse) toJSON(v interface{}) []byte {
+	b, err := json.Marshal(v)
+	if err != nil {
+		logger.Error("encoding error: %v", err)
+		return []byte("")
+	}
+
+	return b
+}
+
+// NewJSONResponse returns a new JSONResponse.
+func NewJSONResponse(w http.ResponseWriter, r *http.Request) *JSONResponse {
+	return &JSONResponse{request: r, writer: w}
+}