cipd: Refactor client to make it more readable.

go/src/infra/tools/cipd/storage_test.go

Index: go/src/infra/tools/cipd/storage_test.go
diff --git a/go/src/infra/tools/cipd/storage_test.go b/go/src/infra/tools/cipd/storage_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..adbd11323b7c431ef777ef167fb6646a167d15e9
--- /dev/null
+++ b/go/src/infra/tools/cipd/storage_test.go
@@ -0,0 +1,113 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package cipd
+
+import (
+	"bytes"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+	"testing"
+
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func TestUpload(t *testing.T) {
+	Convey("Upload full flow", t, func(c C) {
+		storage := mockStorageImpl(c, []expectedHTTPCall{
+			{
+				Method:  "PUT",
+				Path:    "/upl",
+				Body:    "01234",
+				Headers: http.Header{"Content-Range": []string{"bytes 0-4/13"}},
+			},
+			{
+				Method:  "PUT",
+				Path:    "/upl",
+				Body:    "56789",
+				Headers: http.Header{"Content-Range": []string{"bytes 5-9/13"}},
+			},
+			// Insert a error.
+			{
+				Method:  "PUT",
+				Path:    "/upl",
+				Body:    "abc",
+				Headers: http.Header{"Content-Range": []string{"bytes 10-12/13"}},
+				Status:  500,
+			},
+			// Request for uploaded offset #1: failed itself.
+			{
+				Method:  "PUT",
+				Path:    "/upl",
+				Body:    "",
+				Headers: http.Header{"Content-Range": []string{"bytes */13"}},
+				Status:  500,
+			},
+			// Request for uploaded offset #2: indicates part of data uploaded.
+			{
+				Method:          "PUT",
+				Path:            "/upl",
+				Body:            "",
+				Headers:         http.Header{"Content-Range": []string{"bytes */13"}},
+				Status:          308,
+				ResponseHeaders: http.Header{"Range": []string{"bytes=0-7"}},
+			},
+			// Resume of the upload from returned offset.
+			{
+				Method:  "PUT",
+				Path:    "/upl",
+				Body:    "89abc",
+				Headers: http.Header{"Content-Range": []string{"bytes 8-12/13"}},
+			},
+		})
+		err := storage.upload("http://localhost/upl", bytes.NewReader([]byte("0123456789abc")))
+		So(err, ShouldBeNil)
+	})
+}
+
+func TestDownload(t *testing.T) {
+	Convey("With temp directory", t, func() {
+		tempDir, err := ioutil.TempDir("", "cipd_test")
+		So(err, ShouldBeNil)
+		Reset(func() { os.RemoveAll(tempDir) })
+		tempFile := filepath.Join(tempDir, "pkg")
+
+		Convey("Download full flow", func(c C) {
+			out, err := os.OpenFile(tempFile, os.O_RDWR|os.O_CREATE, 0666)
+			So(err, ShouldBeNil)
+			defer out.Close()
+
+			storage := mockStorageImpl(c, []expectedHTTPCall{
+				// Simulate a transient error.
+				{
+					Method: "GET",
+					Path:   "/dwn",
+					Status: 500,
+					Reply:  "error",
+				},
+				{
+					Method: "GET",
+					Path:   "/dwn",
+					Status: 200,
+					Reply:  "file data",
+				},
+			})
+			err = storage.download("http://localhost/dwn", out)
+			So(err, ShouldBeNil)
+
+			out.Seek(0, os.SEEK_SET)
+			fetched, err := ioutil.ReadAll(out)
+			So(err, ShouldBeNil)
+			So(string(fetched), ShouldEqual, "file data")
+		})
+	})
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+func mockStorageImpl(c C, expectations []expectedHTTPCall) *storageImpl {
+	return &storageImpl{client: mockClient(c, expectations), chunkSize: 5}
+}