client_golang/api/prometheus/v1/api.go

498 lines
13 KiB
Go

// Copyright 2017 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.
// +build go1.7
// Package v1 provides bindings to the Prometheus HTTP API v1:
// http://prometheus.io/docs/querying/api/
package v1
import (
"context"
"encoding/json"
"fmt"
"net/http"
"strconv"
"time"
"github.com/prometheus/client_golang/api"
"github.com/prometheus/common/model"
)
const (
statusAPIError = 422
apiPrefix = "/api/v1"
epAlertManagers = apiPrefix + "/alertmanagers"
epQuery = apiPrefix + "/query"
epQueryRange = apiPrefix + "/query_range"
epLabelValues = apiPrefix + "/label/:name/values"
epSeries = apiPrefix + "/series"
epTargets = apiPrefix + "/targets"
epSnapshot = apiPrefix + "/admin/tsdb/snapshot"
epDeleteSeries = apiPrefix + "/admin/tsdb/delete_series"
epCleanTombstones = apiPrefix + "/admin/tsdb/clean_tombstones"
epConfig = apiPrefix + "/status/config"
epFlags = apiPrefix + "/status/flags"
)
// ErrorType models the different API error types.
type ErrorType string
// HealthStatus models the health status of a scrape target.
type HealthStatus string
const (
// Possible values for ErrorType.
ErrBadData ErrorType = "bad_data"
ErrTimeout = "timeout"
ErrCanceled = "canceled"
ErrExec = "execution"
ErrBadResponse = "bad_response"
// Possible values for HealthStatus.
HealthGood HealthStatus = "up"
HealthUnknown HealthStatus = "unknown"
HealthBad HealthStatus = "down"
)
// Error is an error returned by the API.
type Error struct {
Type ErrorType
Msg string
}
func (e *Error) Error() string {
return fmt.Sprintf("%s: %s", e.Type, e.Msg)
}
// Range represents a sliced time range.
type Range struct {
// The boundaries of the time range.
Start, End time.Time
// The maximum time between two slices within the boundaries.
Step time.Duration
}
// API provides bindings for Prometheus's v1 API.
type API interface {
// AlertManagers returns an overview of the current state of the Prometheus alert manager discovery.
AlertManagers(ctx context.Context) (AlertManagersResult, error)
// CleanTombstones removes the deleted data from disk and cleans up the existing tombstones.
CleanTombstones(ctx context.Context) error
// Config returns the current Prometheus configuration.
Config(ctx context.Context) (ConfigResult, error)
// DeleteSeries deletes data for a selection of series in a time range.
DeleteSeries(ctx context.Context, matches []string, startTime time.Time, endTime time.Time) error
// Flags returns the flag values that Prometheus was launched with.
Flags(ctx context.Context) (FlagsResult, error)
// LabelValues performs a query for the values of the given label.
LabelValues(ctx context.Context, label string) (model.LabelValues, error)
// Query performs a query for the given time.
Query(ctx context.Context, query string, ts time.Time) (model.Value, error)
// QueryRange performs a query for the given range.
QueryRange(ctx context.Context, query string, r Range) (model.Value, error)
// Series finds series by label matchers.
Series(ctx context.Context, matches []string, startTime time.Time, endTime time.Time) ([]model.LabelSet, error)
// Snapshot creates a snapshot of all current data into snapshots/<datetime>-<rand>
// under the TSDB's data directory and returns the directory as response.
Snapshot(ctx context.Context, skipHead bool) (SnapshotResult, error)
// Targets returns an overview of the current state of the Prometheus target discovery.
Targets(ctx context.Context) (TargetsResult, error)
}
// AlertManagersResult contains the result from querying the alertmanagers endpoint.
type AlertManagersResult struct {
Active []AlertManager `json:"activeAlertManagers"`
Dropped []AlertManager `json:"droppedAlertManagers"`
}
// AlertManager models a configured Alert Manager.
type AlertManager struct {
URL string `json:"url"`
}
// ConfigResult contains the result from querying the config endpoint.
type ConfigResult struct {
YAML string `json:"yaml"`
}
// FlagsResult contains the result from querying the flag endpoint.
type FlagsResult map[string]string
// SnapshotResult contains the result from querying the snapshot endpoint.
type SnapshotResult struct {
Name string `json:"name"`
}
// TargetsResult contains the result from querying the targets endpoint.
type TargetsResult struct {
Active []ActiveTarget `json:"activeTargets"`
Dropped []DroppedTarget `json:"droppedTargets"`
}
// ActiveTarget models an active Prometheus scrape target.
type ActiveTarget struct {
DiscoveredLabels model.LabelSet `json:"discoveredLabels"`
Labels model.LabelSet `json:"labels"`
ScrapeURL string `json:"scrapeUrl"`
LastError string `json:"lastError"`
LastScrape time.Time `json:"lastScrape"`
Health HealthStatus `json:"health"`
}
// DroppedTarget models a dropped Prometheus scrape target.
type DroppedTarget struct {
DiscoveredLabels model.LabelSet `json:"discoveredLabels"`
}
// queryResult contains result data for a query.
type queryResult struct {
Type model.ValueType `json:"resultType"`
Result interface{} `json:"result"`
// The decoded value.
v model.Value
}
func (qr *queryResult) UnmarshalJSON(b []byte) error {
v := struct {
Type model.ValueType `json:"resultType"`
Result json.RawMessage `json:"result"`
}{}
err := json.Unmarshal(b, &v)
if err != nil {
return err
}
switch v.Type {
case model.ValScalar:
var sv model.Scalar
err = json.Unmarshal(v.Result, &sv)
qr.v = &sv
case model.ValVector:
var vv model.Vector
err = json.Unmarshal(v.Result, &vv)
qr.v = vv
case model.ValMatrix:
var mv model.Matrix
err = json.Unmarshal(v.Result, &mv)
qr.v = mv
default:
err = fmt.Errorf("unexpected value type %q", v.Type)
}
return err
}
// NewAPI returns a new API for the client.
//
// It is safe to use the returned API from multiple goroutines.
func NewAPI(c api.Client) API {
return &httpAPI{client: apiClient{c}}
}
type httpAPI struct {
client api.Client
}
func (h *httpAPI) AlertManagers(ctx context.Context) (AlertManagersResult, error) {
u := h.client.URL(epAlertManagers, nil)
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return AlertManagersResult{}, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return AlertManagersResult{}, err
}
var res AlertManagersResult
err = json.Unmarshal(body, &res)
return res, err
}
func (h *httpAPI) CleanTombstones(ctx context.Context) error {
u := h.client.URL(epCleanTombstones, nil)
req, err := http.NewRequest(http.MethodPost, u.String(), nil)
if err != nil {
return err
}
_, _, err = h.client.Do(ctx, req)
return err
}
func (h *httpAPI) Config(ctx context.Context) (ConfigResult, error) {
u := h.client.URL(epConfig, nil)
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return ConfigResult{}, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return ConfigResult{}, err
}
var res ConfigResult
err = json.Unmarshal(body, &res)
return res, err
}
func (h *httpAPI) DeleteSeries(ctx context.Context, matches []string, startTime time.Time, endTime time.Time) error {
u := h.client.URL(epDeleteSeries, nil)
q := u.Query()
for _, m := range matches {
q.Add("match[]", m)
}
q.Set("start", startTime.Format(time.RFC3339Nano))
q.Set("end", endTime.Format(time.RFC3339Nano))
u.RawQuery = q.Encode()
req, err := http.NewRequest(http.MethodPost, u.String(), nil)
if err != nil {
return err
}
_, _, err = h.client.Do(ctx, req)
return err
}
func (h *httpAPI) Flags(ctx context.Context) (FlagsResult, error) {
u := h.client.URL(epFlags, nil)
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return FlagsResult{}, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return FlagsResult{}, err
}
var res FlagsResult
err = json.Unmarshal(body, &res)
return res, err
}
func (h *httpAPI) LabelValues(ctx context.Context, label string) (model.LabelValues, error) {
u := h.client.URL(epLabelValues, map[string]string{"name": label})
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return nil, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return nil, err
}
var labelValues model.LabelValues
err = json.Unmarshal(body, &labelValues)
return labelValues, err
}
func (h *httpAPI) Query(ctx context.Context, query string, ts time.Time) (model.Value, error) {
u := h.client.URL(epQuery, nil)
q := u.Query()
q.Set("query", query)
if !ts.IsZero() {
q.Set("time", ts.Format(time.RFC3339Nano))
}
u.RawQuery = q.Encode()
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return nil, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return nil, err
}
var qres queryResult
err = json.Unmarshal(body, &qres)
return model.Value(qres.v), err
}
func (h *httpAPI) QueryRange(ctx context.Context, query string, r Range) (model.Value, error) {
u := h.client.URL(epQueryRange, nil)
q := u.Query()
var (
start = r.Start.Format(time.RFC3339Nano)
end = r.End.Format(time.RFC3339Nano)
step = strconv.FormatFloat(r.Step.Seconds(), 'f', 3, 64)
)
q.Set("query", query)
q.Set("start", start)
q.Set("end", end)
q.Set("step", step)
u.RawQuery = q.Encode()
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return nil, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return nil, err
}
var qres queryResult
err = json.Unmarshal(body, &qres)
return model.Value(qres.v), err
}
func (h *httpAPI) Series(ctx context.Context, matches []string, startTime time.Time, endTime time.Time) ([]model.LabelSet, error) {
u := h.client.URL(epSeries, nil)
q := u.Query()
for _, m := range matches {
q.Add("match[]", m)
}
q.Set("start", startTime.Format(time.RFC3339Nano))
q.Set("end", endTime.Format(time.RFC3339Nano))
u.RawQuery = q.Encode()
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return nil, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return nil, err
}
var mset []model.LabelSet
err = json.Unmarshal(body, &mset)
return mset, err
}
func (h *httpAPI) Snapshot(ctx context.Context, skipHead bool) (SnapshotResult, error) {
u := h.client.URL(epSnapshot, nil)
q := u.Query()
q.Set("skip_head", strconv.FormatBool(skipHead))
u.RawQuery = q.Encode()
req, err := http.NewRequest(http.MethodPost, u.String(), nil)
if err != nil {
return SnapshotResult{}, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return SnapshotResult{}, err
}
var res SnapshotResult
err = json.Unmarshal(body, &res)
return res, err
}
func (h *httpAPI) Targets(ctx context.Context) (TargetsResult, error) {
u := h.client.URL(epTargets, nil)
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
return TargetsResult{}, err
}
_, body, err := h.client.Do(ctx, req)
if err != nil {
return TargetsResult{}, err
}
var res TargetsResult
err = json.Unmarshal(body, &res)
return res, err
}
// apiClient wraps a regular client and processes successful API responses.
// Successful also includes responses that errored at the API level.
type apiClient struct {
api.Client
}
type apiResponse struct {
Status string `json:"status"`
Data json.RawMessage `json:"data"`
ErrorType ErrorType `json:"errorType"`
Error string `json:"error"`
}
func (c apiClient) Do(ctx context.Context, req *http.Request) (*http.Response, []byte, error) {
resp, body, err := c.Client.Do(ctx, req)
if err != nil {
return resp, body, err
}
code := resp.StatusCode
if code/100 != 2 && code != statusAPIError {
return resp, body, &Error{
Type: ErrBadResponse,
Msg: fmt.Sprintf("bad response code %d", resp.StatusCode),
}
}
var result apiResponse
if err = json.Unmarshal(body, &result); err != nil {
return resp, body, &Error{
Type: ErrBadResponse,
Msg: err.Error(),
}
}
if (code == statusAPIError) != (result.Status == "error") {
err = &Error{
Type: ErrBadResponse,
Msg: "inconsistent body for response code",
}
}
if code == statusAPIError && result.Status == "error" {
err = &Error{
Type: result.ErrorType,
Msg: result.Error,
}
}
return resp, []byte(result.Data), err
}