Initial commit

vendor/github.com/hyperhq/hypercli/pkg/authorization/response.go

@@ -0,0 +1,136 @@
+package authorization
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net"
+	"net/http"
+)
+
+// ResponseModifier allows authorization plugins to read and modify the content of the http.response
+type ResponseModifier interface {
+	http.ResponseWriter
+
+	// RawBody returns the current http content
+	RawBody() []byte
+
+	// RawHeaders returns the current content of the http headers
+	RawHeaders() ([]byte, error)
+
+	// StatusCode returns the current status code
+	StatusCode() int
+
+	// OverrideBody replace the body of the HTTP reply
+	OverrideBody(b []byte)
+
+	// OverrideHeader replace the headers of the HTTP reply
+	OverrideHeader(b []byte) error
+
+	// OverrideStatusCode replaces the status code of the HTTP reply
+	OverrideStatusCode(statusCode int)
+
+	// Flush flushes all data to the HTTP response
+	Flush() error
+}
+
+// NewResponseModifier creates a wrapper to an http.ResponseWriter to allow inspecting and modifying the content
+func NewResponseModifier(rw http.ResponseWriter) ResponseModifier {
+	return &responseModifier{rw: rw, header: make(http.Header)}
+}
+
+// responseModifier is used as an adapter to http.ResponseWriter in order to manipulate and explore
+// the http request/response from docker daemon
+type responseModifier struct {
+	// The original response writer
+	rw     http.ResponseWriter
+	status int
+	// body holds the response body
+	body []byte
+	// header holds the response header
+	header http.Header
+	// statusCode holds the response status code
+	statusCode int
+}
+
+// WriterHeader stores the http status code
+func (rm *responseModifier) WriteHeader(s int) {
+	rm.statusCode = s
+}
+
+// Header returns the internal http header
+func (rm *responseModifier) Header() http.Header {
+	return rm.header
+}
+
+// Header returns the internal http header
+func (rm *responseModifier) StatusCode() int {
+	return rm.statusCode
+}
+
+// Override replace the body of the HTTP reply
+func (rm *responseModifier) OverrideBody(b []byte) {
+	rm.body = b
+}
+
+func (rm *responseModifier) OverrideStatusCode(statusCode int) {
+	rm.statusCode = statusCode
+}
+
+// Override replace the headers of the HTTP reply
+func (rm *responseModifier) OverrideHeader(b []byte) error {
+	header := http.Header{}
+	if err := json.Unmarshal(b, &header); err != nil {
+		return err
+	}
+	rm.header = header
+	return nil
+}
+
+// Write stores the byte array inside content
+func (rm *responseModifier) Write(b []byte) (int, error) {
+	rm.body = append(rm.body, b...)
+	return len(b), nil
+}
+
+// Body returns the response body
+func (rm *responseModifier) RawBody() []byte {
+	return rm.body
+}
+
+func (rm *responseModifier) RawHeaders() ([]byte, error) {
+	var b bytes.Buffer
+	if err := rm.header.Write(&b); err != nil {
+		return nil, err
+	}
+	return b.Bytes(), nil
+}
+
+// Hijack returns the internal connection of the wrapped http.ResponseWriter
+func (rm *responseModifier) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	hijacker, ok := rm.rw.(http.Hijacker)
+	if !ok {
+		return nil, nil, fmt.Errorf("Internal reponse writer doesn't support the Hijacker interface")
+	}
+	return hijacker.Hijack()
+}
+
+// Flush flushes all data to the HTTP response
+func (rm *responseModifier) Flush() error {
+	// Copy the status code
+	if rm.statusCode > 0 {
+		rm.rw.WriteHeader(rm.statusCode)
+	}
+
+	// Copy the header
+	for k, vv := range rm.header {
+		for _, v := range vv {
+			rm.rw.Header().Add(k, v)
+		}
+	}
+
+	// Write body
+	_, err := rm.rw.Write(rm.body)
+	return err
+}