client_golang/prometheus/http_test.go

235 lines
6.4 KiB
Go

// Copyright 2014 The Prometheus Authors
// 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 prometheus
import (
"bytes"
"errors"
"log"
"net/http"
"net/http/httptest"
"testing"
"time"
dto "github.com/prometheus/client_model/go"
)
type respBody string
func (b respBody) ServeHTTP(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(http.StatusTeapot)
w.Write([]byte(b))
}
func TestInstrumentHandler(t *testing.T) {
defer func(n nower) {
now = n.(nower)
}(now)
instant := time.Now()
end := instant.Add(30 * time.Second)
now = nowSeries(instant, end)
respBody := respBody("Howdy there!")
hndlr := InstrumentHandler("test-handler", respBody)
opts := SummaryOpts{
Subsystem: "http",
ConstLabels: Labels{"handler": "test-handler"},
}
reqCnt := MustRegisterOrGet(NewCounterVec(
CounterOpts{
Namespace: opts.Namespace,
Subsystem: opts.Subsystem,
Name: "requests_total",
Help: "Total number of HTTP requests made.",
ConstLabels: opts.ConstLabels,
},
instLabels,
)).(*CounterVec)
opts.Name = "request_duration_microseconds"
opts.Help = "The HTTP request latencies in microseconds."
reqDur := MustRegisterOrGet(NewSummary(opts)).(Summary)
opts.Name = "request_size_bytes"
opts.Help = "The HTTP request sizes in bytes."
MustRegisterOrGet(NewSummary(opts))
opts.Name = "response_size_bytes"
opts.Help = "The HTTP response sizes in bytes."
MustRegisterOrGet(NewSummary(opts))
reqCnt.Reset()
resp := httptest.NewRecorder()
req := &http.Request{
Method: "GET",
}
hndlr.ServeHTTP(resp, req)
if resp.Code != http.StatusTeapot {
t.Fatalf("expected status %d, got %d", http.StatusTeapot, resp.Code)
}
if string(resp.Body.Bytes()) != "Howdy there!" {
t.Fatalf("expected body %s, got %s", "Howdy there!", string(resp.Body.Bytes()))
}
out := &dto.Metric{}
reqDur.Write(out)
if want, got := "test-handler", out.Label[0].GetValue(); want != got {
t.Errorf("want label value %q in reqDur, got %q", want, got)
}
if want, got := uint64(1), out.Summary.GetSampleCount(); want != got {
t.Errorf("want sample count %d in reqDur, got %d", want, got)
}
out.Reset()
if want, got := 1, len(reqCnt.children); want != got {
t.Errorf("want %d children in reqCnt, got %d", want, got)
}
cnt, err := reqCnt.GetMetricWithLabelValues("get", "418")
if err != nil {
t.Fatal(err)
}
cnt.Write(out)
if want, got := "418", out.Label[0].GetValue(); want != got {
t.Errorf("want label value %q in reqCnt, got %q", want, got)
}
if want, got := "test-handler", out.Label[1].GetValue(); want != got {
t.Errorf("want label value %q in reqCnt, got %q", want, got)
}
if want, got := "get", out.Label[2].GetValue(); want != got {
t.Errorf("want label value %q in reqCnt, got %q", want, got)
}
if out.Counter == nil {
t.Fatal("expected non-nil counter in reqCnt")
}
if want, got := 1., out.Counter.GetValue(); want != got {
t.Errorf("want reqCnt of %f, got %f", want, got)
}
}
type errorCollector struct{}
func (e errorCollector) Describe(ch chan<- *Desc) {
ch <- NewDesc("invalid_metric", "not helpful", nil, nil)
}
func (e errorCollector) Collect(ch chan<- Metric) {
ch <- NewInvalidMetric(
NewDesc("invalid_metric", "not helpful", nil, nil),
errors.New("collect error"),
)
}
func TestHandlerErrorHandling(t *testing.T) {
// Create a registry that collects a MetricFamily with two elements,
// another with one, and reports an error.
reg := NewRegistry()
cnt := NewCounter(CounterOpts{
Name: "the_count",
Help: "Ah-ah-ah! Thunder and lightning!",
})
MustRegisterWith(reg, cnt)
cntVec := NewCounterVec(
CounterOpts{
Name: "name",
Help: "docstring",
ConstLabels: Labels{"constname": "constvalue"},
},
[]string{"labelname"},
)
cntVec.WithLabelValues("val1").Inc()
cntVec.WithLabelValues("val2").Inc()
MustRegisterWith(reg, cntVec)
MustRegisterWith(reg, errorCollector{})
logBuf := &bytes.Buffer{}
logger := log.New(logBuf, "", 0)
writer := httptest.NewRecorder()
request, _ := http.NewRequest("GET", "/", nil)
request.Header.Add("Accept", "test/plain")
errorHandler := HandlerFor(reg, HandlerOpts{
ErrorLog: logger,
ErrorHandling: HTTPErrorOnError,
})
continueHandler := HandlerFor(reg, HandlerOpts{
ErrorLog: logger,
ErrorHandling: ContinueOnError,
})
panicHandler := HandlerFor(reg, HandlerOpts{
ErrorLog: logger,
ErrorHandling: PanicOnError,
})
wantMsg := `error collecting metrics: 1 error(s) occurred:
* error collecting metric Desc{fqName: "invalid_metric", help: "not helpful", constLabels: {}, variableLabels: []}: collect error
`
wantErrorBody := `An error has occurred during metrics collection:
1 error(s) occurred:
* error collecting metric Desc{fqName: "invalid_metric", help: "not helpful", constLabels: {}, variableLabels: []}: collect error
`
wantOKBody := `# HELP name docstring
# TYPE name counter
name{constname="constvalue",labelname="val1"} 1
name{constname="constvalue",labelname="val2"} 1
# HELP the_count Ah-ah-ah! Thunder and lightning!
# TYPE the_count counter
the_count 0
`
errorHandler.ServeHTTP(writer, request)
if got, want := writer.Code, http.StatusInternalServerError; got != want {
t.Errorf("got HTTP status code %d, want %d", got, want)
}
if got := logBuf.String(); got != wantMsg {
t.Errorf("got log message %q, want %q", got, wantMsg)
}
if got := writer.Body.String(); got != wantErrorBody {
t.Errorf("got body %q, want %q", got, wantErrorBody)
}
logBuf.Reset()
writer.Body.Reset()
writer.Code = http.StatusOK
continueHandler.ServeHTTP(writer, request)
if got, want := writer.Code, http.StatusOK; got != want {
t.Errorf("got HTTP status code %d, want %d", got, want)
}
if got := logBuf.String(); got != wantMsg {
t.Errorf("got log message %q, want %q", got, wantMsg)
}
if got := writer.Body.String(); got != wantOKBody {
t.Errorf("got body %q, want %q", got, wantOKBody)
}
defer func() {
if err := recover(); err == nil {
t.Error("expected panic from panicHandler")
}
}()
panicHandler.ServeHTTP(writer, request)
}