upgrade prometheus client-go

Signed-off-by: zackzhangkai <zackzhang@yunify.com>

vendor/github.com/prometheus-community/prom-label-proxy/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
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+
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+   limitations under the License.

vendor/github.com/prometheus-community/prom-label-proxy/injectproxy/enforce.go

@@ -0,0 +1,130 @@
+// Copyright 2020 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 injectproxy
+
+import (
+	"fmt"
+
+	"github.com/prometheus/prometheus/pkg/labels"
+	"github.com/prometheus/prometheus/promql/parser"
+)
+
+type Enforcer struct {
+	labelMatchers map[string]*labels.Matcher
+}
+
+func NewEnforcer(ms ...*labels.Matcher) *Enforcer {
+	entries := make(map[string]*labels.Matcher)
+
+	for _, matcher := range ms {
+		entries[matcher.Name] = matcher
+	}
+
+	return &Enforcer{
+		labelMatchers: entries,
+	}
+}
+
+// EnforceNode walks the given node recursively
+// and enforces the given label enforcer on it.
+//
+// Whenever a parser.MatrixSelector or parser.VectorSelector AST node is found,
+// their label enforcer is being potentially modified.
+// If a node's label matcher has the same name as a label matcher
+// of the given enforcer, then it will be replaced.
+func (ms Enforcer) EnforceNode(node parser.Node) error {
+	switch n := node.(type) {
+	case *parser.EvalStmt:
+		if err := ms.EnforceNode(n.Expr); err != nil {
+			return err
+		}
+
+	case parser.Expressions:
+		for _, e := range n {
+			if err := ms.EnforceNode(e); err != nil {
+				return err
+			}
+		}
+
+	case *parser.AggregateExpr:
+		if err := ms.EnforceNode(n.Expr); err != nil {
+			return err
+		}
+
+	case *parser.BinaryExpr:
+		if err := ms.EnforceNode(n.LHS); err != nil {
+			return err
+		}
+
+		if err := ms.EnforceNode(n.RHS); err != nil {
+			return err
+		}
+
+	case *parser.Call:
+		if err := ms.EnforceNode(n.Args); err != nil {
+			return err
+		}
+
+	case *parser.SubqueryExpr:
+		if err := ms.EnforceNode(n.Expr); err != nil {
+			return err
+		}
+
+	case *parser.ParenExpr:
+		if err := ms.EnforceNode(n.Expr); err != nil {
+			return err
+		}
+
+	case *parser.UnaryExpr:
+		if err := ms.EnforceNode(n.Expr); err != nil {
+			return err
+		}
+
+	case *parser.NumberLiteral, *parser.StringLiteral:
+	// nothing to do
+
+	case *parser.MatrixSelector:
+		// inject labelselector
+		if vs, ok := n.VectorSelector.(*parser.VectorSelector); ok {
+			vs.LabelMatchers = ms.enforceMatchers(vs.LabelMatchers)
+		}
+
+	case *parser.VectorSelector:
+		// inject labelselector
+		n.LabelMatchers = ms.enforceMatchers(n.LabelMatchers)
+
+	default:
+		panic(fmt.Errorf("parser.Walk: unhandled node type %T", n))
+	}
+
+	return nil
+}
+
+func (ms Enforcer) enforceMatchers(targets []*labels.Matcher) []*labels.Matcher {
+	var res []*labels.Matcher
+
+	for _, target := range targets {
+		if _, ok := ms.labelMatchers[target.Name]; ok {
+			continue
+		}
+
+		res = append(res, target)
+	}
+
+	for _, enforcedMatcher := range ms.labelMatchers {
+		res = append(res, enforcedMatcher)
+	}
+
+	return res
+}

vendor/github.com/prometheus-community/prom-label-proxy/injectproxy/routes.go

@@ -0,0 +1,156 @@
+// Copyright 2020 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 injectproxy
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+
+	"github.com/prometheus/prometheus/pkg/labels"
+	"github.com/prometheus/prometheus/promql/parser"
+)
+
+type routes struct {
+	upstream  *url.URL
+	handler   http.Handler
+	label     string
+	mux       *http.ServeMux
+	modifiers map[string]func(*http.Response) error
+}
+
+func NewRoutes(upstream *url.URL, label string) *routes {
+	proxy := httputil.NewSingleHostReverseProxy(upstream)
+
+	r := &routes{
+		upstream: upstream,
+		handler:  proxy,
+		label:    label,
+	}
+	mux := http.NewServeMux()
+	mux.Handle("/federate", enforceMethods(r.federate, "GET"))
+	mux.Handle("/api/v1/query", enforceMethods(r.query, "GET", "POST"))
+	mux.Handle("/api/v1/query_range", enforceMethods(r.query, "GET", "POST"))
+	mux.Handle("/api/v1/alerts", enforceMethods(r.noop, "GET"))
+	mux.Handle("/api/v1/rules", enforceMethods(r.noop, "GET"))
+	mux.Handle("/api/v2/silences", enforceMethods(r.silences, "GET", "POST"))
+	mux.Handle("/api/v2/silences/", enforceMethods(r.silences, "GET", "POST"))
+	mux.Handle("/api/v2/silence/", enforceMethods(r.deleteSilence, "DELETE"))
+	r.mux = mux
+	r.modifiers = map[string]func(*http.Response) error{
+		"/api/v1/rules":  modifyAPIResponse(r.filterRules),
+		"/api/v1/alerts": modifyAPIResponse(r.filterAlerts),
+	}
+	proxy.ModifyResponse = r.ModifyResponse
+	return r
+}
+
+func (r *routes) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	lvalue := req.URL.Query().Get(r.label)
+	if lvalue == "" {
+		http.Error(w, fmt.Sprintf("Bad request. The %q query parameter must be provided.", r.label), http.StatusBadRequest)
+		return
+	}
+	req = req.WithContext(withLabelValue(req.Context(), lvalue))
+	// Remove the proxy label from the query parameters.
+	q := req.URL.Query()
+	q.Del(r.label)
+	req.URL.RawQuery = q.Encode()
+
+	r.mux.ServeHTTP(w, req)
+}
+
+func (r *routes) ModifyResponse(resp *http.Response) error {
+	m, found := r.modifiers[resp.Request.URL.Path]
+	if !found {
+		// Return the server's response unmodified.
+		return nil
+	}
+	return m(resp)
+}
+
+func enforceMethods(h http.HandlerFunc, methods ...string) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		for _, m := range methods {
+			if m == req.Method {
+				h(w, req)
+				return
+			}
+		}
+		http.NotFound(w, req)
+	})
+}
+
+type ctxKey int
+
+const keyLabel ctxKey = iota
+
+func mustLabelValue(ctx context.Context) string {
+	label, ok := ctx.Value(keyLabel).(string)
+	if !ok {
+		panic(fmt.Sprintf("can't find the %q value in the context", keyLabel))
+	}
+	if label == "" {
+		panic(fmt.Sprintf("empty %q value in the context", keyLabel))
+	}
+	return label
+}
+
+func withLabelValue(ctx context.Context, label string) context.Context {
+	return context.WithValue(ctx, keyLabel, label)
+}
+
+func (r *routes) noop(w http.ResponseWriter, req *http.Request) {
+	r.handler.ServeHTTP(w, req)
+}
+
+func (r *routes) query(w http.ResponseWriter, req *http.Request) {
+	expr, err := parser.ParseExpr(req.FormValue("query"))
+	if err != nil {
+		return
+	}
+
+	e := NewEnforcer([]*labels.Matcher{
+		{
+			Name:  r.label,
+			Type:  labels.MatchEqual,
+			Value: mustLabelValue(req.Context()),
+		},
+	}...)
+	if err := e.EnforceNode(expr); err != nil {
+		return
+	}
+
+	q := req.URL.Query()
+	q.Set("query", expr.String())
+	req.URL.RawQuery = q.Encode()
+
+	r.handler.ServeHTTP(w, req)
+}
+
+func (r *routes) federate(w http.ResponseWriter, req *http.Request) {
+	matcher := &labels.Matcher{
+		Name:  r.label,
+		Type:  labels.MatchEqual,
+		Value: mustLabelValue(req.Context()),
+	}
+
+	q := req.URL.Query()
+	q.Set("match[]", "{"+matcher.String()+"}")
+	req.URL.RawQuery = q.Encode()
+
+	r.handler.ServeHTTP(w, req)
+}

vendor/github.com/prometheus-community/prom-label-proxy/injectproxy/rules.go

@@ -0,0 +1,243 @@
+// Copyright 2020 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 injectproxy
+
+import (
+	"bytes"
+	"compress/gzip"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"time"
+
+	"github.com/pkg/errors"
+	"github.com/prometheus/prometheus/pkg/labels"
+)
+
+type apiResponse struct {
+	Status    string          `json:"status"`
+	Data      json.RawMessage `json:"data,omitempty"`
+	ErrorType string          `json:"errorType,omitempty"`
+	Error     string          `json:"error,omitempty"`
+	Warnings  []string        `json:"warnings,omitempty"`
+}
+
+func getAPIResponse(resp *http.Response) (*apiResponse, error) {
+	defer resp.Body.Close()
+	reader := resp.Body
+
+	if resp.Header.Get("Content-Encoding") == "gzip" && !resp.Uncompressed {
+		var err error
+		reader, err = gzip.NewReader(resp.Body)
+		if err != nil {
+			return nil, errors.Wrap(err, "gzip decoding")
+		}
+		defer reader.Close()
+
+		// TODO: recompress the modified response?
+		resp.Header.Del("Content-Encoding")
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	var apir apiResponse
+	if err := json.NewDecoder(reader).Decode(&apir); err != nil {
+		return nil, errors.Wrap(err, "JSON decoding")
+	}
+
+	if apir.Status != "success" {
+		return nil, fmt.Errorf("unexpected response status: %q", apir.Status)
+	}
+
+	return &apir, nil
+}
+
+type rulesData struct {
+	RuleGroups []*ruleGroup `json:"groups"`
+}
+
+type ruleGroup struct {
+	Name     string  `json:"name"`
+	File     string  `json:"file"`
+	Rules    []rule  `json:"rules"`
+	Interval float64 `json:"interval"`
+}
+
+type rule struct {
+	*alertingRule
+	*recordingRule
+}
+
+func (r *rule) Labels() labels.Labels {
+	if r.alertingRule != nil {
+		return r.alertingRule.Labels
+	}
+	return r.recordingRule.Labels
+}
+
+// MarshalJSON implements the json.Marshaler interface for rule.
+func (r *rule) MarshalJSON() ([]byte, error) {
+	if r.alertingRule != nil {
+		return json.Marshal(r.alertingRule)
+	}
+	return json.Marshal(r.recordingRule)
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface for rule.
+func (r *rule) UnmarshalJSON(b []byte) error {
+	var ruleType struct {
+		Type string `json:"type"`
+	}
+	if err := json.Unmarshal(b, &ruleType); err != nil {
+		return err
+	}
+	switch ruleType.Type {
+	case "alerting":
+		var alertingr alertingRule
+		if err := json.Unmarshal(b, &alertingr); err != nil {
+			return err
+		}
+		r.alertingRule = &alertingr
+	case "recording":
+		var recordingr recordingRule
+		if err := json.Unmarshal(b, &recordingr); err != nil {
+			return err
+		}
+		r.recordingRule = &recordingr
+	default:
+		return fmt.Errorf("failed to unmarshal rule: unknown type %q", ruleType.Type)
+	}
+
+	return nil
+}
+
+type alertingRule struct {
+	Name        string        `json:"name"`
+	Query       string        `json:"query"`
+	Duration    float64       `json:"duration"`
+	Labels      labels.Labels `json:"labels"`
+	Annotations labels.Labels `json:"annotations"`
+	Alerts      []*alert      `json:"alerts"`
+	Health      string        `json:"health"`
+	LastError   string        `json:"lastError,omitempty"`
+	// Type of an alertingRule is always "alerting".
+	Type string `json:"type"`
+}
+
+type recordingRule struct {
+	Name      string        `json:"name"`
+	Query     string        `json:"query"`
+	Labels    labels.Labels `json:"labels,omitempty"`
+	Health    string        `json:"health"`
+	LastError string        `json:"lastError,omitempty"`
+	// Type of a recordingRule is always "recording".
+	Type string `json:"type"`
+}
+
+type alertsData struct {
+	Alerts []*alert `json:"alerts"`
+}
+
+type alert struct {
+	Labels      labels.Labels `json:"labels"`
+	Annotations labels.Labels `json:"annotations"`
+	State       string        `json:"state"`
+	ActiveAt    *time.Time    `json:"activeAt,omitempty"`
+	Value       string        `json:"value"`
+}
+
+// modifyAPIResponse unwraps the Prometheus API response, passes the enforced
+// label value and the response to the given function and finally replaces the
+// result in the response.
+func modifyAPIResponse(f func(string, *apiResponse) (interface{}, error)) func(*http.Response) error {
+	return func(resp *http.Response) error {
+		if resp.StatusCode != http.StatusOK {
+			// Pass non-200 responses as-is.
+			return nil
+		}
+
+		apir, err := getAPIResponse(resp)
+		if err != nil {
+			return errors.Wrap(err, "can't decode API response")
+		}
+
+		v, err := f(mustLabelValue(resp.Request.Context()), apir)
+		if err != nil {
+			return err
+		}
+
+		b, err := json.Marshal(v)
+		if err != nil {
+			return errors.Wrap(err, "can't replace data")
+		}
+		apir.Data = json.RawMessage(b)
+
+		var buf bytes.Buffer
+		if err = json.NewEncoder(&buf).Encode(apir); err != nil {
+			return errors.Wrap(err, "can't encode API response")
+		}
+		resp.Body = ioutil.NopCloser(&buf)
+		resp.Header["Content-Length"] = []string{fmt.Sprint(buf.Len())}
+
+		return nil
+	}
+}
+
+func (r *routes) filterRules(lvalue string, resp *apiResponse) (interface{}, error) {
+	var rgs rulesData
+	if err := json.Unmarshal(resp.Data, &rgs); err != nil {
+		return nil, errors.Wrap(err, "can't decode rules data")
+	}
+
+	filtered := []*ruleGroup{}
+	for _, rg := range rgs.RuleGroups {
+		var rules []rule
+		for _, rule := range rg.Rules {
+			for _, lbl := range rule.Labels() {
+				if lbl.Name == r.label && lbl.Value == lvalue {
+					rules = append(rules, rule)
+					break
+				}
+			}
+		}
+		if len(rules) > 0 {
+			rg.Rules = rules
+			filtered = append(filtered, rg)
+		}
+	}
+
+	return &rulesData{RuleGroups: filtered}, nil
+}
+
+func (r *routes) filterAlerts(lvalue string, resp *apiResponse) (interface{}, error) {
+	var data alertsData
+	if err := json.Unmarshal(resp.Data, &data); err != nil {
+		return nil, errors.Wrap(err, "can't decode alerts data")
+	}
+
+	filtered := []*alert{}
+	for _, alert := range data.Alerts {
+		for _, lbl := range alert.Labels {
+			if lbl.Name == r.label && lbl.Value == lvalue {
+				filtered = append(filtered, alert)
+				break
+			}
+		}
+	}
+
+	return &alertsData{Alerts: filtered}, nil
+}

vendor/github.com/prometheus-community/prom-label-proxy/injectproxy/silences.go

@@ -0,0 +1,176 @@
+// Copyright 2020 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 injectproxy
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"path"
+	"strconv"
+	"strings"
+
+	runtimeclient "github.com/go-openapi/runtime/client"
+	"github.com/go-openapi/strfmt"
+	"github.com/prometheus/alertmanager/api/v2/client"
+	"github.com/prometheus/alertmanager/api/v2/client/silence"
+	"github.com/prometheus/alertmanager/api/v2/models"
+	"github.com/prometheus/alertmanager/pkg/labels"
+)
+
+func (r *routes) silences(w http.ResponseWriter, req *http.Request) {
+	switch req.Method {
+	case "GET":
+		r.listSilences(w, req)
+	case "POST":
+		r.postSilence(w, req)
+	default:
+		http.NotFound(w, req)
+	}
+}
+
+func (r *routes) listSilences(w http.ResponseWriter, req *http.Request) {
+	var (
+		q               = req.URL.Query()
+		proxyLabelMatch = labels.Matcher{
+			Type:  labels.MatchEqual,
+			Name:  r.label,
+			Value: mustLabelValue(req.Context()),
+		}
+		modified = []string{proxyLabelMatch.String()}
+	)
+	for _, filter := range q["filter"] {
+		m, err := labels.ParseMatcher(filter)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("bad request: can't parse filter %q: %v", filter, err), http.StatusBadRequest)
+			return
+		}
+		if m.Name == r.label {
+			continue
+		}
+		modified = append(modified, filter)
+	}
+
+	q["filter"] = modified
+	q.Del(r.label)
+	req.URL.RawQuery = q.Encode()
+
+	r.handler.ServeHTTP(w, req)
+}
+
+func (r *routes) postSilence(w http.ResponseWriter, req *http.Request) {
+	var (
+		sil    models.PostableSilence
+		lvalue = mustLabelValue(req.Context())
+	)
+	if err := json.NewDecoder(req.Body).Decode(&sil); err != nil {
+		http.Error(w, fmt.Sprintf("bad request: can't decode: %v", err), http.StatusBadRequest)
+		return
+	}
+
+	if sil.ID != "" {
+		// This is an update for an existing silence.
+		existing, err := r.getSilenceByID(req.Context(), sil.ID)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("proxy error: can't get silence: %v", err), http.StatusBadGateway)
+			return
+		}
+
+		if !hasMatcherForLabel(existing.Matchers, r.label, lvalue) {
+			http.Error(w, "forbidden", http.StatusForbidden)
+			return
+		}
+	}
+
+	var falsy bool
+	modified := models.Matchers{
+		&models.Matcher{Name: &(r.label), Value: &lvalue, IsRegex: &falsy},
+	}
+	for _, m := range sil.Matchers {
+		if m.Name != nil && *m.Name == r.label {
+			continue
+		}
+		modified = append(modified, m)
+	}
+	// At least one matcher in addition to the enforced label is required,
+	// otherwise all alerts would be silenced
+	if len(modified) < 2 {
+		http.Error(w, "need at least one matcher, got none", http.StatusBadRequest)
+		return
+	}
+	sil.Matchers = modified
+
+	var buf bytes.Buffer
+	if err := json.NewEncoder(&buf).Encode(&sil); err != nil {
+		http.Error(w, fmt.Sprintf("can't encode: %v", err), http.StatusInternalServerError)
+		return
+	}
+
+	req = req.Clone(req.Context())
+	req.Body = ioutil.NopCloser(&buf)
+	req.URL.RawQuery = ""
+	req.Header["Content-Length"] = []string{strconv.Itoa(buf.Len())}
+	req.ContentLength = int64(buf.Len())
+
+	r.handler.ServeHTTP(w, req)
+}
+
+func (r *routes) deleteSilence(w http.ResponseWriter, req *http.Request) {
+	silID := strings.TrimPrefix(req.URL.Path, "/api/v2/silence/")
+	if silID == "" || silID == req.URL.Path {
+		http.Error(w, "bad request", http.StatusBadRequest)
+		return
+	}
+
+	// Get the silence by ID and verify that it has the expected label.
+	sil, err := r.getSilenceByID(req.Context(), silID)
+	if err != nil {
+		http.Error(w, fmt.Sprintf("proxy error: %v", err), http.StatusBadGateway)
+		return
+	}
+
+	if !hasMatcherForLabel(sil.Matchers, r.label, mustLabelValue(req.Context())) {
+		http.Error(w, "forbidden", http.StatusForbidden)
+		return
+	}
+
+	req.URL.RawQuery = ""
+	r.handler.ServeHTTP(w, req)
+}
+
+func (r *routes) getSilenceByID(ctx context.Context, id string) (*models.GettableSilence, error) {
+	amc := client.New(
+		runtimeclient.New(r.upstream.Host, path.Join(r.upstream.Path, "/api/v2"), []string{r.upstream.Scheme}),
+		strfmt.Default,
+	)
+	params := silence.NewGetSilenceParams().WithContext(ctx)
+	params.SetSilenceID(strfmt.UUID(id))
+	sil, err := amc.Silence.GetSilence(params)
+	if err != nil {
+		return nil, err
+	}
+	return sil.Payload, nil
+}
+
+func hasMatcherForLabel(matchers models.Matchers, name, value string) bool {
+	for _, m := range matchers {
+		if *m.Name == name && !*m.IsRegex && *m.Value == value {
+			return true
+		}
+	}
+	return false
+}