initial commit

vendor/github.com/ant0ine/go-json-rest/rest/json_indent.go

@@ -0,0 +1,113 @@
+package rest
+
+import (
+	"bufio"
+	"encoding/json"
+	"net"
+	"net/http"
+)
+
+// JsonIndentMiddleware provides JSON encoding with indentation.
+// It could be convenient to use it during development.
+// It works by "subclassing" the responseWriter provided by the wrapping middleware,
+// replacing the writer.EncodeJson and writer.WriteJson implementations,
+// and making the parent implementations ignored.
+type JsonIndentMiddleware struct {
+
+	// prefix string, as in json.MarshalIndent
+	Prefix string
+
+	// indentation string, as in json.MarshalIndent
+	Indent string
+}
+
+// MiddlewareFunc makes JsonIndentMiddleware implement the Middleware interface.
+func (mw *JsonIndentMiddleware) MiddlewareFunc(handler HandlerFunc) HandlerFunc {
+
+	if mw.Indent == "" {
+		mw.Indent = "  "
+	}
+
+	return func(w ResponseWriter, r *Request) {
+
+		writer := &jsonIndentResponseWriter{w, false, mw.Prefix, mw.Indent}
+		// call the wrapped handler
+		handler(writer, r)
+	}
+}
+
+// Private responseWriter intantiated by the middleware.
+// It implements the following interfaces:
+// ResponseWriter
+// http.ResponseWriter
+// http.Flusher
+// http.CloseNotifier
+// http.Hijacker
+type jsonIndentResponseWriter struct {
+	ResponseWriter
+	wroteHeader bool
+	prefix      string
+	indent      string
+}
+
+// Replace the parent EncodeJson to provide indentation.
+func (w *jsonIndentResponseWriter) EncodeJson(v interface{}) ([]byte, error) {
+	b, err := json.MarshalIndent(v, w.prefix, w.indent)
+	if err != nil {
+		return nil, err
+	}
+	return b, nil
+}
+
+// Make sure the local EncodeJson and local Write are called.
+// Does not call the parent WriteJson.
+func (w *jsonIndentResponseWriter) WriteJson(v interface{}) error {
+	b, err := w.EncodeJson(v)
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(b)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Call the parent WriteHeader.
+func (w *jsonIndentResponseWriter) WriteHeader(code int) {
+	w.ResponseWriter.WriteHeader(code)
+	w.wroteHeader = true
+}
+
+// Make sure the local WriteHeader is called, and call the parent Flush.
+// Provided in order to implement the http.Flusher interface.
+func (w *jsonIndentResponseWriter) Flush() {
+	if !w.wroteHeader {
+		w.WriteHeader(http.StatusOK)
+	}
+	flusher := w.ResponseWriter.(http.Flusher)
+	flusher.Flush()
+}
+
+// Call the parent CloseNotify.
+// Provided in order to implement the http.CloseNotifier interface.
+func (w *jsonIndentResponseWriter) CloseNotify() <-chan bool {
+	notifier := w.ResponseWriter.(http.CloseNotifier)
+	return notifier.CloseNotify()
+}
+
+// Provided in order to implement the http.Hijacker interface.
+func (w *jsonIndentResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	hijacker := w.ResponseWriter.(http.Hijacker)
+	return hijacker.Hijack()
+}
+
+// Make sure the local WriteHeader is called, and call the parent Write.
+// Provided in order to implement the http.ResponseWriter interface.
+func (w *jsonIndentResponseWriter) Write(b []byte) (int, error) {
+	if !w.wroteHeader {
+		w.WriteHeader(http.StatusOK)
+	}
+	writer := w.ResponseWriter.(http.ResponseWriter)
+	return writer.Write(b)
+}