pkg/client: make Describe use a POST request to the server

Otherwise it can't send Describe Rules.

Also in this commit: a bunch of new tests from when I thought I was going crazy
and trying to debug the search system, before I realized the problem was that the
client was doing a GET request and dropping most of my DescribeRequest.

Change-Id: I4ea9bed80f0d7d6b86814527b63acc3586ac1d06

pkg/client/client.go

@@ -475,8 +475,12 @@ func (c *Client) Describe(req *search.DescribeRequest) (*search.DescribeResponse
 	if err != nil {
 		return nil, err
 	}
-	url := sr + req.URLSuffix()
+	url := sr + req.URLSuffixPost()
-	hreq := c.newRequest("GET", url)
+	body, err := json.MarshalIndent(req, "", "\t")
+	if err != nil {
+		return nil, err
+	}
+	hreq := c.newRequest("POST", url, bytes.NewReader(body))
 	hres, err := c.expect2XX(hreq)
 	if err != nil {
 		return nil, err

pkg/search/describe.go

@@ -249,6 +249,13 @@ func (m MetaMap) Get(br blob.Ref) *DescribedBlob {
 	return m[br.String()]
 }
 
+// URLSuffixPost returns the URL suffix for POST requests.
+func (r *DescribeRequest) URLSuffixPost() string {
+	return "camli/search/describe"
+}
+
+// URLSuffix returns the URL suffix for GET requests.
+// This is deprecated.
 func (r *DescribeRequest) URLSuffix() string {
 	var buf bytes.Buffer
 	fmt.Fprintf(&buf, "camli/search/describe?depth=%d&maxdirchildren=%d",

pkg/search/describe_test.go

@@ -74,6 +74,12 @@ func searchDescribeSetup(fi *test.FakeIndex) index.Interface {
 	addPermanode(fi, "somevenuepic-0",
 		"foo", "bar",
 	)
+	addPermanode(fi, "venuepic-2",
+		"camliContent", "somevenuepic-2",
+	)
+	addPermanode(fi, "somevenuepic-2",
+		"foo", "baz",
+	)
 
 	addPermanode(fi, "homedir-0",
 		"camliPath:subdir.1", "homedir-1",
@@ -85,6 +91,11 @@ func searchDescribeSetup(fi *test.FakeIndex) index.Interface {
 		"foo", "bar",
 	)
 
+	addPermanode(fi, "set-0",
+		"camliMember", "venuepic-1",
+		"camliMember", "venuepic-2",
+	)
+
 	return fi
 }
 
@@ -206,6 +217,23 @@ var searchDescribeTests = []handlerTest{
 		}),
 		wantDescribed: []string{"homedir-0", "homedir-1", "homedir-2"},
 	},
+
+	{
+		name: "find members",
+		postBody: marshalJSON(&search.DescribeRequest{
+			BlobRef: blob.MustParse("set-0"),
+			Rules: []*search.DescribeRule{
+				{
+					IfResultRoot: true,
+					Attrs:        []string{"camliMember"},
+					Rules: []*search.DescribeRule{
+						{Attrs: []string{"camliContent"}},
+					},
+				},
+			},
+		}),
+		wantDescribed: []string{"set-0", "venuepic-1", "venuepic-2", "somevenuepic-0", "somevenuepic-2"},
+	},
 }
 
 func init() {