Merge lp:~allenap/gwacl/storage-get-blob into lp:gwacl

[Gavin Panella]

New Storage API operation to get a blob.

[Julian Edwards (julian-edwards)]

review: Approve

[lp:~allenap/gwacl/storage-get-blob]

56. By Gavin Panella on 2013-03-22

Assert instead of Check that the reader is not nil.

=== modified file 'storage.go'
--- storage.go	2013-03-22 06:34:24 +0000
+++ storage.go	2013-03-22 06:54:19 +0000
@@ -421,3 +421,23 @@
     }
     return nil
 }
+
+// Get the specified blob from the given container.
+func (context *StorageContext) GetBlob(container, filename string) (io.ReadCloser, error) {
+    uri := fmt.Sprintf(
+        "http://%s.blob.core.windows.net/%s/%s",
+        context.Account, container, filename)
+    req, err := http.NewRequest("GET", uri, nil)
+    if err != nil {
+        return nil, err
+    }
+    addStandardHeaders(req, context.Account, context.Key, "2012-02-12")
+    resp, err := context.send(req, nil)
+    if err != nil {
+        return nil, err
+    }
+    if resp.StatusCode != http.StatusOK {
+        return nil, fmt.Errorf("failed to get blob: %s", resp.Status)
+    }
+    return resp.Body, nil
+}
 
=== modified file 'storage_test.go'
--- storage_test.go	2013-03-22 06:34:24 +0000
+++ storage_test.go	2013-03-22 06:54:19 +0000
@@ -768,3 +768,59 @@
     err := context.DeleteBlob("container", "blobname")
     c.Assert(err.Error(), Equals, "failed to delete blob: 246 Frotzed")
 }
+
+type TestGetBlob struct{}
+
+var _ = Suite(&TestGetBlob{})
+
+func (suite *TestGetBlob) Test(c *C) {
+    context := makeStorageContext()
+    response_body := "blob-in-a-can"
+    response := &http.Response{
+        Status:     fmt.Sprintf("%d", http.StatusOK),
+        StatusCode: http.StatusOK,
+        Body:       ioutil.NopCloser(strings.NewReader(response_body)),
+    }
+    transport := &TestTransport{Response: response}
+    context.client = &http.Client{Transport: transport}
+    reader, err := context.GetBlob("container", "blobname")
+    c.Assert(reader, NotNil)
+    defer reader.Close()
+    c.Assert(err, IsNil)
+
+    c.Check(transport.Request.Method, Equals, "GET")
+    c.Check(transport.Request.URL.String(), Equals, fmt.Sprintf(
+        "http://%s.blob.core.windows.net/container/blobname",
+        context.Account))
+    c.Check(transport.Request.Header.Get("Authorization"), Not(Equals), "")
+
+    data, err := ioutil.ReadAll(reader)
+    c.Assert(err, IsNil)
+    c.Check(string(data), Equals, response_body)
+}
+
+// Client-side errors from the HTTP client are propagated back to the caller.
+func (suite *TestGetBlob) TestError(c *C) {
+    error := fmt.Errorf("canned-error")
+    transport := &TestTransport{Error: error}
+    context := makeStorageContext()
+    context.client = &http.Client{Transport: transport}
+    reader, err := context.GetBlob("container", "blobname")
+    c.Check(reader, IsNil)
+    c.Assert(err, NotNil)
+}
+
+// Server-side errors are propagated back to the caller.
+func (suite *TestGetBlob) TestErrorResponse(c *C) {
+    response := &http.Response{
+        Status:     "246 Frotzed",
+        StatusCode: 246,
+    }
+    transport := &TestTransport{Response: response}
+    context := makeStorageContext()
+    context.client = &http.Client{Transport: transport}
+    reader, err := context.GetBlob("container", "blobname")
+    c.Check(reader, IsNil)
+    c.Assert(err, NotNil)
+    c.Assert(err.Error(), Equals, "failed to get blob: 246 Frotzed")
+}