Initial commit

utils_test.go

@@ -0,0 +1,126 @@
+package docker
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"io/ioutil"
+	"testing"
+)
+
+func TestBufReader(t *testing.T) {
+	reader, writer := io.Pipe()
+	bufreader := newBufReader(reader)
+
+	// Write everything down to a Pipe
+	// Usually, a pipe should block but because of the buffered reader,
+	// the writes will go through
+	done := make(chan bool)
+	go func() {
+		writer.Write([]byte("hello world"))
+		writer.Close()
+		done <- true
+	}()
+
+	// Drain the reader *after* everything has been written, just to verify
+	// it is indeed buffering
+	<-done
+	output, err := ioutil.ReadAll(bufreader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(output, []byte("hello world")) {
+		t.Error(string(output))
+	}
+}
+
+type dummyWriter struct {
+	buffer      bytes.Buffer
+	failOnWrite bool
+}
+
+func (dw *dummyWriter) Write(p []byte) (n int, err error) {
+	if dw.failOnWrite {
+		return 0, errors.New("Fake fail")
+	}
+	return dw.buffer.Write(p)
+}
+
+func (dw *dummyWriter) String() string {
+	return dw.buffer.String()
+}
+
+func (dw *dummyWriter) Close() error {
+	return nil
+}
+
+func TestWriteBroadcaster(t *testing.T) {
+	writer := newWriteBroadcaster()
+
+	// Test 1: Both bufferA and bufferB should contain "foo"
+	bufferA := &dummyWriter{}
+	writer.AddWriter(bufferA)
+	bufferB := &dummyWriter{}
+	writer.AddWriter(bufferB)
+	writer.Write([]byte("foo"))
+
+	if bufferA.String() != "foo" {
+		t.Errorf("Buffer contains %v", bufferA.String())
+	}
+
+	if bufferB.String() != "foo" {
+		t.Errorf("Buffer contains %v", bufferB.String())
+	}
+
+	// Test2: bufferA and bufferB should contain "foobar",
+	// while bufferC should only contain "bar"
+	bufferC := &dummyWriter{}
+	writer.AddWriter(bufferC)
+	writer.Write([]byte("bar"))
+
+	if bufferA.String() != "foobar" {
+		t.Errorf("Buffer contains %v", bufferA.String())
+	}
+
+	if bufferB.String() != "foobar" {
+		t.Errorf("Buffer contains %v", bufferB.String())
+	}
+
+	if bufferC.String() != "bar" {
+		t.Errorf("Buffer contains %v", bufferC.String())
+	}
+
+	// Test3: Test removal
+	writer.RemoveWriter(bufferB)
+	writer.Write([]byte("42"))
+	if bufferA.String() != "foobar42" {
+		t.Errorf("Buffer contains %v", bufferA.String())
+	}
+	if bufferB.String() != "foobar" {
+		t.Errorf("Buffer contains %v", bufferB.String())
+	}
+	if bufferC.String() != "bar42" {
+		t.Errorf("Buffer contains %v", bufferC.String())
+	}
+
+	// Test4: Test eviction on failure
+	bufferA.failOnWrite = true
+	writer.Write([]byte("fail"))
+	if bufferA.String() != "foobar42" {
+		t.Errorf("Buffer contains %v", bufferA.String())
+	}
+	if bufferC.String() != "bar42fail" {
+		t.Errorf("Buffer contains %v", bufferC.String())
+	}
+	// Even though we reset the flag, no more writes should go in there
+	bufferA.failOnWrite = false
+	writer.Write([]byte("test"))
+	if bufferA.String() != "foobar42" {
+		t.Errorf("Buffer contains %v", bufferA.String())
+	}
+	if bufferC.String() != "bar42failtest" {
+		t.Errorf("Buffer contains %v", bufferC.String())
+	}
+
+	writer.Close()
+}