change how tracing query comments are handled

go/trace/opentracing.go

@@ -17,13 +17,13 @@ limitations under the License.
 package trace
 
 import (
- "strings"
+ "encoding/base64"
+ "encoding/json"
 
  otgrpc "github.com/opentracing-contrib/go-grpc"
  "github.com/opentracing/opentracing-go"
  "golang.org/x/net/context"
  "google.golang.org/grpc"
- "vitess.io/vitess/go/vt/proto/vtrpc"
  "vitess.io/vitess/go/vt/vterrors"
 )
 
@@ -86,19 +86,18 @@ func (jf openTracingService) New(parent Span, label string) Span {
 }
 
 func extractMapFromString(in string) (opentracing.TextMapCarrier, error) {
- m := make(opentracing.TextMapCarrier)
- items := strings.Split(in, ":")
- if len(items) < 2 {
- return nil, vterrors.Errorf(vtrpc.Code_INVALID_ARGUMENT, "expected transmitted context to contain at least span id and trace id")
+ decodedBytes, err := base64.StdEncoding.DecodeString(in)
+ if err != nil {
+ return nil, err
  }
- for _, v := range items {
- idx := strings.Index(v, "=")
- if idx < 1 {
- return nil, vterrors.Errorf(vtrpc.Code_INVALID_ARGUMENT, "every element in the context string has to be in the form key=value")
- }
- m[v[0:idx]] = v[idx+1:]
+
+ var dat opentracing.TextMapCarrier
+ err = json.Unmarshal(decodedBytes, &dat)
+ if err != nil {
+ return nil, err
  }
- return m, nil
+
+ return dat, nil
 }
 
 func (jf openTracingService) NewFromString(parent, label string) (Span, error) {

go/trace/opentracing_test.go

@@ -17,6 +17,8 @@ limitations under the License.
 package trace
 
 import (
+ "encoding/base64"
+ "encoding/json"
  "testing"
 
  "github.com/opentracing/opentracing-go"
@@ -25,17 +27,23 @@ import (
 
 func TestExtractMapFromString(t *testing.T) {
  expected := make(opentracing.TextMapCarrier)
- expected["apa"] = "12"
- expected["banan"] = "x-tracing-backend-12"
- result, err := extractMapFromString("apa=12:banan=x-tracing-backend-12")
+ expected["uber-trace-id"] = "123:456:789:1"
+ expected["other data with weird symbols:!#;"] = ":1!\""
+ jsonBytes, err := json.Marshal(expected)
+ assert.NoError(t, err)
+
+ encodedString := base64.StdEncoding.EncodeToString(jsonBytes)
+
+ result, err := extractMapFromString(encodedString)
  assert.NoError(t, err)
  assert.Equal(t, expected, result)
 }
 
 func TestErrorConditions(t *testing.T) {
- _, err := extractMapFromString("")
+ encodedString := base64.StdEncoding.EncodeToString([]byte(`{"key":42}`))
+ _, err := extractMapFromString(encodedString) // malformed json {"key":42}
  assert.Error(t, err)
 
- _, err = extractMapFromString("key=value:keywithnovalue")
+ _, err = extractMapFromString("this is not base64") // malformed base64
  assert.Error(t, err)
 }