Provide Discriminator For Protocol Buf. Streams

This commit introduces an incomplete processor that decodes varint
record length-delimited streams of io.prometheus.client.MetricFamily
Protocol Buffer messages.  The Go client presently does not support
generation of said messages, but this will unblock a number of Java
changes.
This commit is contained in:
Matt T. Proud 2013-06-26 13:25:10 +02:00
parent 6da8b95237
commit 03369306e0
4 changed files with 75 additions and 19 deletions

View File

@ -31,24 +31,34 @@ func ProcessorForRequestHeader(header http.Header) (Processor, error) {
if err != nil {
return nil, fmt.Errorf("Invalid Content-Type header %q: %s", header.Get("Content-Type"), err)
}
if mediatype != "application/json" {
switch mediatype {
case "application/vnd.google.protobuf":
if params["proto"] != "io.prometheus.client.MetricFamily" {
return nil, fmt.Errorf("Unrecognized Protocol Message %s", params["proto"])
}
if params["encoding"] != "varint record length-delimited" {
return nil, fmt.Errorf("Unsupported Encoding %s", params["encoding"])
}
return MetricFamilyProcessor, nil
case "application/json":
var prometheusApiVersion string
if params["schema"] == "prometheus/telemetry" && params["version"] != "" {
prometheusApiVersion = params["version"]
} else {
prometheusApiVersion = header.Get("X-Prometheus-API-Version")
}
switch prometheusApiVersion {
case "0.0.2":
return Processor002, nil
case "0.0.1":
return Processor001, nil
default:
return nil, fmt.Errorf("Unrecognized API version %s", prometheusApiVersion)
}
default:
return nil, fmt.Errorf("Unsupported media type %q, expected %q", mediatype, "application/json")
}
var prometheusApiVersion string
if params["schema"] == "prometheus/telemetry" && params["version"] != "" {
prometheusApiVersion = params["version"]
} else {
prometheusApiVersion = header.Get("X-Prometheus-API-Version")
}
switch prometheusApiVersion {
case "0.0.2":
return Processor002, nil
case "0.0.1":
return Processor001, nil
default:
return nil, fmt.Errorf("Unrecognized API version %s", prometheusApiVersion)
}
}

View File

@ -56,6 +56,21 @@ func testDiscriminatorHttpHeader(t test.Tester) {
output: Processor002,
err: nil,
},
{
input: map[string]string{"Content-Type": `application/vnd.google.protobuf; proto="io.prometheus.client.MetricFamily"; encoding="varint record length-delimited"`},
output: MetricFamilyProcessor,
err: nil,
},
{
input: map[string]string{"Content-Type": `application/vnd.google.protobuf; proto="illegal"; encoding="varint record length-delimited"`},
output: nil,
err: fmt.Errorf("Unrecognized Protocol Message illegal"),
},
{
input: map[string]string{"Content-Type": `application/vnd.google.protobuf; proto="io.prometheus.client.MetricFamily"; encoding="illegal"`},
output: nil,
err: fmt.Errorf("Unsupported Encoding illegal"),
},
}
for i, scenario := range scenarios {

View File

@ -0,0 +1,31 @@
// Copyright 2013 Prometheus Team
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package extraction
import (
"io"
)
type metricFamilyProcessor struct{}
// MetricFamilyProcessor decodes varint encoded record length-delimited streams
// of io.prometheus.client.MetricFamily.
//
// See http://godoc.org/github.com/matttproud/golang_protobuf_extensions/ext for
// more details.
var MetricFamilyProcessor = new(metricFamilyProcessor)
func (m *metricFamilyProcessor) ProcessSingle(io.Reader, chan<- *Result, *ProcessOptions) error {
panic("not implemented")
}

View File

@ -23,7 +23,7 @@ import (
// Processor002 is responsible for decoding payloads from protocol version
// 0.0.2.
var Processor002 = &processor002{}
var Processor002 = new(processor002)
type histogram002 struct {
Labels map[string]string `json:"labels"`