feat: reuse jira clients to reuse connections

cmd/jiralert/main.go

@@ -22,10 +22,11 @@
 	"runtime"
 	"strconv"
 
 	"github.com/andygrunwald/go-jira"
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/prometheus-community/jiralert/pkg/alertmanager"
+	"github.com/prometheus-community/jiralert/pkg/clientset"
 	"github.com/prometheus-community/jiralert/pkg/config"
 	"github.com/prometheus-community/jiralert/pkg/notify"
 	"github.com/prometheus-community/jiralert/pkg/template"
@@ -87,6 +88,8 @@
 		os.Exit(1)
 	}
 
+	var cs clientset.ClientSet
+
 	http.HandleFunc("/alert", func(w http.ResponseWriter, req *http.Request) {
 		level.Debug(logger).Log("msg", "handling /alert webhook request")
 		defer func() { _ = req.Body.Close() }()
@@ -105,22 +108,7 @@
 		}
 		level.Debug(logger).Log("msg", "  matched receiver", "receiver", conf.Name)
 
-		// TODO: Consider reusing notifiers or just jira clients to reuse connections.
-		var client *jira.Client
-		var err error
-		if conf.User != "" && conf.Password != "" {
-			tp := jira.BasicAuthTransport{
-				Username: conf.User,
-				Password: string(conf.Password),
-			}
-			client, err = jira.NewClient(tp.Client(), conf.APIURL)
-		} else if conf.PersonalAccessToken != "" {
-			tp := jira.PATAuthTransport{
-				Token: string(conf.PersonalAccessToken),
-			}
-			client, err = jira.NewClient(tp.Client(), conf.APIURL)
-		}
-
+		client, err := cs.GetOrCreateJira(conf)
 		if err != nil {
 			errorHandler(w, http.StatusInternalServerError, err, conf.Name, &data, logger)
 			return

pkg/clientset/clientset.go

@@ -0,0 +1,84 @@
+// 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.
+
+package clientset
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+
+	"github.com/andygrunwald/go-jira"
+	"github.com/prometheus-community/jiralert/pkg/config"
+)
+
+type ClientSet struct {
+	jira map[string]*jira.Client
+	sync.RWMutex
+}
+
+var errorClientExists = errors.New("client already exists")
+
+func (c *ClientSet) getJira(userName string) (*jira.Client, bool) {
+	c.RLock()
+	if c.jira == nil {
+		c.jira = map[string]*jira.Client{}
+	}
+	jc, ok := c.jira[userName]
+	c.RUnlock()
+
+	return jc, ok
+}
+
+func (c *ClientSet) newJira(conf *config.ReceiverConfig) (*jira.Client, error) {
+	if conf == nil {
+		return nil, fmt.Errorf("missing receiver config")
+	}
+
+	if jc, ok := c.getJira(conf.User); ok {
+		return jc, fmt.Errorf("jira %w: %s", errorClientExists, conf.User)
+	}
+
+	var (
+		client *jira.Client
+		err    error
+	)
+	if conf.User != "" && conf.Password != "" {
+		tp := jira.BasicAuthTransport{
+			Username: conf.User,
+			Password: string(conf.Password),
+		}
+		client, err = jira.NewClient(tp.Client(), conf.APIURL)
+	} else if conf.PersonalAccessToken != "" {
+		tp := jira.PATAuthTransport{
+			Token: string(conf.PersonalAccessToken),
+		}
+		client, err = jira.NewClient(tp.Client(), conf.APIURL)
+	}
+
+	if err == nil {
+		c.Lock()
+		c.jira[conf.User] = client
+		c.Unlock()
+	}
+
+	return client, err
+}
+
+func (c *ClientSet) GetOrCreateJira(conf *config.ReceiverConfig) (*jira.Client, error) {
+	jc, err := c.newJira(conf)
+	if errors.Is(err, errorClientExists) {
+		err = nil
+	}
+	return jc, err
+}