Pod log subresource

Adds a Log subresource to Pod storage. The Log subresource implements
rest.GetterWithOptions and produces a ResourceStreamer resource that
will stream the log output from the pod's host node.

pkg/registry/generic/rest/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package rest has generic implementations of resources used for
+// REST responses
+package rest

pkg/registry/generic/rest/streamer.go

@@ -0,0 +1,69 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rest
+
+import (
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/rest"
+)
+
+// LocationStreamer is a resource that streams the contents of a particular
+// location URL
+type LocationStreamer struct {
+	Location    *url.URL
+	Transport   http.RoundTripper
+	ContentType string
+	Flush       bool
+}
+
+// a LocationStreamer must implement a rest.ResourceStreamer
+var _ rest.ResourceStreamer = &LocationStreamer{}
+
+// IsAnAPIObject marks this object as a runtime.Object
+func (*LocationStreamer) IsAnAPIObject() {}
+
+// InputStream returns a stream with the contents of the URL location. If no location is provided,
+// a null stream is returned.
+func (s *LocationStreamer) InputStream(apiVersion, acceptHeader string) (stream io.ReadCloser, flush bool, contentType string, err error) {
+	if s.Location == nil {
+		// If no location was provided, return a null stream
+		return nil, false, "", nil
+	}
+	transport := s.Transport
+	if transport == nil {
+		transport = http.DefaultTransport
+	}
+	client := &http.Client{Transport: transport}
+	resp, err := client.Get(s.Location.String())
+	if err != nil {
+		return
+	}
+	contentType = s.ContentType
+	if len(contentType) == 0 {
+		contentType = resp.Header.Get("Content-Type")
+		if len(contentType) > 0 {
+			contentType = strings.TrimSpace(strings.SplitN(contentType, ";", 2)[0])
+		}
+	}
+	flush = s.Flush
+	stream = resp.Body
+	return
+}

pkg/registry/generic/rest/streamer_test.go

@@ -0,0 +1,118 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rest
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+)
+
+func TestInputStreamReader(t *testing.T) {
+	resultString := "Test output"
+	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		w.Write([]byte(resultString))
+	}))
+	defer s.Close()
+	u, err := url.Parse(s.URL)
+	if err != nil {
+		t.Errorf("Error parsing server URL: %v", err)
+		return
+	}
+	streamer := &LocationStreamer{
+		Location: u,
+	}
+	readCloser, _, _, err := streamer.InputStream("v1beta1", "text/plain")
+	if err != nil {
+		t.Errorf("Unexpected error when getting stream: %v", err)
+		return
+	}
+	defer readCloser.Close()
+	result, err := ioutil.ReadAll(readCloser)
+	if string(result) != resultString {
+		t.Errorf("Stream content does not match. Got: %s. Expected: %s.", string(result), resultString)
+	}
+}
+
+func TestInputStreamNullLocation(t *testing.T) {
+	streamer := &LocationStreamer{
+		Location: nil,
+	}
+	readCloser, _, _, err := streamer.InputStream("v1beta1", "text/plain")
+	if err != nil {
+		t.Errorf("Unexpected error when getting stream with null location: %v", err)
+	}
+	if readCloser != nil {
+		t.Errorf("Expected stream to be nil. Got: %#v", readCloser)
+	}
+}
+
+type testTransport struct {
+	body string
+	err  error
+}
+
+func (tt *testTransport) RoundTrip(req *http.Request) (*http.Response, error) {
+	r := bufio.NewReader(bytes.NewBufferString(tt.body))
+	return http.ReadResponse(r, req)
+}
+
+func fakeTransport(mime, message string) http.RoundTripper {
+	content := fmt.Sprintf("HTTP/1.1 200 OK\nContent-Type: %s\n\n%s", mime, message)
+	return &testTransport{body: content}
+}
+
+func TestInputStreamContentType(t *testing.T) {
+	location, _ := url.Parse("http://www.example.com")
+	streamer := &LocationStreamer{
+		Location:  location,
+		Transport: fakeTransport("application/json", "hello world"),
+	}
+	readCloser, _, contentType, err := streamer.InputStream("v1beta1", "text/plain")
+	if err != nil {
+		t.Errorf("Unexpected error when getting stream: %v", err)
+		return
+	}
+	defer readCloser.Close()
+	if contentType != "application/json" {
+		t.Errorf("Unexpected content type. Got: %s. Expected: application/json", contentType)
+	}
+}
+
+func TestInputStreamTransport(t *testing.T) {
+	message := "hello world"
+	location, _ := url.Parse("http://www.example.com")
+	streamer := &LocationStreamer{
+		Location:  location,
+		Transport: fakeTransport("text/plain", message),
+	}
+	readCloser, _, _, err := streamer.InputStream("v1beta1", "text/plain")
+	if err != nil {
+		t.Errorf("Unexpected error when getting stream: %v", err)
+		return
+	}
+	defer readCloser.Close()
+	result, err := ioutil.ReadAll(readCloser)
+	if string(result) != message {
+		t.Errorf("Stream content does not match. Got: %s. Expected: %s.", string(result), message)
+	}
+}