server, docs: change rowBin to request. (pingcap#5983)

docs/tidb_http_api.md

@@ -96,9 +96,11 @@ timezone.*
     curl http://{TiDBIP}:10080/settings
     ```
 
-1. Get the column value by an encoded row and some information that can be obtained from a column of the table schema information.
+1. Get the column value by an encoded row and some information that can be obtained from a column of the table schema information. 
+
+    Argument example: rowBin=base64_encoded_row_value
 
     ```shell
-    curl http://{TiDBIP}:10080/tables/{colID}/{colFlag}/{colLen}/{rowBin}
+    curl http://{TiDBIP}:10080/tables/{colID}/{colFlag}/{colLen}?rowBin={val}
     ```
     *Hint: For the column which field type is timezone dependent, e.g. `timestamp`, convert its value to UTC timezone.*

server/http_handler.go

@@ -342,8 +342,25 @@ func (vh valueHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	// Get binary.
-	bin := params[pRowBin]
+	// Get the unchanged binary.
+	if req.URL == nil {
+		err = errors.BadRequestf("Invalid URL")
+		writeError(w, err)
+		return
+	}
+	values := make(url.Values)
+	shouldUnescape := false
+	err = parseQuery(req.URL.RawQuery, values, shouldUnescape)
+	if err != nil {
+		writeError(w, err)
+		return
+	}
+	if len(values[pRowBin]) != 1 {
+		err = errors.BadRequestf("Invalid Query:%v", values[pRowBin])
+		writeError(w, err)
+		return
+	}
+	bin := values[pRowBin][0]
 	valData, err := base64.StdEncoding.DecodeString(bin)
 	if err != nil {
 		writeError(w, err)
@@ -882,11 +899,13 @@ func (r RegionFrameRange) lastTableID() int64 {
 	return r.last.TableID
 }
 
-// parseQuery is used to parse query string in URL, due to golang http package can not distinguish
+// parseQuery is used to parse query string in URL with shouldUnescape, due to golang http package can not distinguish
 // query like "?a=" and "?a". We rewrite it to separate these two queries. e.g.
 // "?a=" which means that a is an empty string "";
 // "?a"  which means that a is null.
-func parseQuery(query string, m url.Values) error {
+// If shouldUnescape is true, we use QueryUnescape to handle keys and values that will be put in m.
+// If shouldUnescape is false, we don't use QueryUnescap to handle.
+func parseQuery(query string, m url.Values, shouldUnescape bool) error {
 	var err error
 	for query != "" {
 		key := query
@@ -901,19 +920,23 @@ func parseQuery(query string, m url.Values) error {
 		if i := strings.Index(key, "="); i >= 0 {
 			value := ""
 			key, value = key[:i], key[i+1:]
-			key, err = url.QueryUnescape(key)
-			if err != nil {
-				return errors.Trace(err)
-			}
-			value, err = url.QueryUnescape(value)
-			if err != nil {
-				return errors.Trace(err)
+			if shouldUnescape {
+				key, err = url.QueryUnescape(key)
+				if err != nil {
+					return errors.Trace(err)
+				}
+				value, err = url.QueryUnescape(value)
+				if err != nil {
+					return errors.Trace(err)
+				}
 			}
 			m[key] = append(m[key], value)
 		} else {
-			key, err = url.QueryUnescape(key)
-			if err != nil {
-				return errors.Trace(err)
+			if shouldUnescape {
+				key, err = url.QueryUnescape(key)
+				if err != nil {
+					return errors.Trace(err)
+				}
 			}
 			if _, ok := m[key]; !ok {
 				m[key] = nil
@@ -937,7 +960,7 @@ func (h mvccTxnHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 			break
 		}
 		values := make(url.Values)
-		err = parseQuery(req.URL.RawQuery, values)
+		err = parseQuery(req.URL.RawQuery, values, true)
 		if err == nil {
 			data, err = h.handleMvccGetByIdx(params, values)
 		}

server/http_handler_test.go

@@ -363,9 +363,10 @@ func (ts *HTTPHandlerTestSuite) TestDecodeColumnValue(c *C) {
 	bs, err := tablecodec.EncodeRow(sc, row, colIDs, nil, nil)
 	c.Assert(err, IsNil)
 	c.Assert(bs, NotNil)
+	bin := base64.StdEncoding.EncodeToString(bs)
 
 	unitTest := func(col *column) {
-		url := fmt.Sprintf("http://127.0.0.1:10090/tables/%d/%v/%d/%d/%s", col.id, col.tp.Tp, col.tp.Flag, col.tp.Flen, base64.StdEncoding.EncodeToString(bs))
+		url := fmt.Sprintf("http://127.0.0.1:10090/tables/%d/%v/%d/%d?rowBin=%s", col.id, col.tp.Tp, col.tp.Flag, col.tp.Flen, bin)
 		resp, err := http.Get(url)
 		c.Assert(err, IsNil, Commentf("url:%s", url))
 		decoder := json.NewDecoder(resp.Body)
@@ -380,6 +381,18 @@ func (ts *HTTPHandlerTestSuite) TestDecodeColumnValue(c *C) {
 	for _, col := range cols {
 		unitTest(col)
 	}
+
+	// Test bin has `+`.
+	// 2018-03-08 16:01:00.315313
+	bin = "CAIIyAEIBAIGYWJjCAYGAQCBCAgJsZ+TgISg1M8Z"
+	row[3] = types.NewTimeDatum(types.Time{Time: types.FromGoTime(time.Date(2018, 3, 8, 16, 1, 0, 315313000, time.UTC)), Fsp: 6, Type: mysql.TypeTimestamp})
+	unitTest(cols[3])
+
+	// Test bin has `/`.
+	// 2018-03-08 02:44:46.409199
+	bin = "CAIIyAEIBAIGYWJjCAYGAQCBCAgJ7/yY8LKF1M8Z"
+	row[3] = types.NewTimeDatum(types.Time{Time: types.FromGoTime(time.Date(2018, 3, 8, 2, 44, 46, 409199000, time.UTC)), Fsp: 6, Type: mysql.TypeTimestamp})
+	unitTest(cols[3])
 }
 
 func (ts *HTTPHandlerTestSuite) TestGetIndexMVCC(c *C) {

server/http_status.go

@@ -53,7 +53,7 @@ func (s *Server) startHTTPServer() {
 	router.Handle("/schema", schemaHandler{tikvHandlerTool})
 	router.Handle("/schema/{db}", schemaHandler{tikvHandlerTool})
 	router.Handle("/schema/{db}/{table}", schemaHandler{tikvHandlerTool})
-	router.Handle("/tables/{colID}/{colTp}/{colFlag}/{colLen}/{rowBin}", valueHandler{})
+	router.Handle("/tables/{colID}/{colTp}/{colFlag}/{colLen}", valueHandler{})
 	if s.cfg.Store == "tikv" {
 		// HTTP path for tikv
 		router.Handle("/tables/{db}/{table}/regions", tableHandler{tikvHandlerTool, opTableRegions})