internal/telemetry/export/ocagent: correctly JSON marshal BucketOptionsExplicit
This change adds a custom MarshalJSON method to BucketOptionsExplicit for
marshalling parity with protobuf/jsonpb. This allows the OpenCensus service
to correctly decode a distribution's BucketOptions.
Updates golang/go#33819
Change-Id: Ia9dc868e1cbfc32a956f6a276dfd1591f7d4d31a
Reviewed-on: https://go-review.googlesource.com/c/tools/+/208398
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/internal/telemetry/export/ocagent/wire/metrics.go b/internal/telemetry/export/ocagent/wire/metrics.go
index d9ff519..5e1b735 100644
--- a/internal/telemetry/export/ocagent/wire/metrics.go
+++ b/internal/telemetry/export/ocagent/wire/metrics.go
@@ -148,6 +148,24 @@
func (BucketOptionsExplicit) tagBucketOptions() {}
+// Declared for the purpose of custom JSON marshalling without cycles.
+type bucketOptionsExplicitAlias BucketOptionsExplicit
+
+// MarshalJSON creates JSON formatted the same way as jsonpb so that the
+// OpenCensus service can correctly determine the underlying value type.
+// This custom MarshalJSON exists because,
+// by default BucketOptionsExplicit is JSON marshalled as:
+// {"bounds":[1,2,3]}
+// but it should be marshalled as:
+// {"explicit":{"bounds":[1,2,3]}}
+func (be *BucketOptionsExplicit) MarshalJSON() ([]byte, error) {
+ return json.Marshal(&struct {
+ Explicit *bucketOptionsExplicitAlias `json:"explicit,omitempty"`
+ }{
+ Explicit: (*bucketOptionsExplicitAlias)(be),
+ })
+}
+
type Bucket struct {
Count int64 `json:"count,omitempty"`
Exemplar *Exemplar `json:"exemplar,omitempty"`
diff --git a/internal/telemetry/export/ocagent/wire/metrics_test.go b/internal/telemetry/export/ocagent/wire/metrics_test.go
index b510ee2..fe2497d 100644
--- a/internal/telemetry/export/ocagent/wire/metrics_test.go
+++ b/internal/telemetry/export/ocagent/wire/metrics_test.go
@@ -44,7 +44,7 @@
Count: 2,
},
},
- BucketOptions: BucketOptionsExplicit{
+ BucketOptions: &BucketOptionsExplicit{
Bounds: []float64{
0, 5,
},
@@ -52,7 +52,7 @@
},
},
},
- `{"distributionValue":{"count":3,"sum":10,"bucket_options":{"bounds":[0,5]},"buckets":[{"count":1},{"count":2}]}}`,
+ `{"distributionValue":{"count":3,"sum":10,"bucket_options":{"explicit":{"bounds":[0,5]}},"buckets":[{"count":1},{"count":2}]}}`,
},
{
"nil point",
