Preserve Alertmanager URLs as *url.URL.

Render a nicer link in the web UI.

notifier/notifier.go

@@ -316,13 +316,13 @@ func (n *Notifier) setMore() {
 	}
 }
 
-// Alertmanagers returns a list Alertmanager URLs.
-func (n *Notifier) Alertmanagers() []string {
+// Alertmanagers returns a slice of Alertmanager URLs.
+func (n *Notifier) Alertmanagers() []*url.URL {
 	n.mtx.RLock()
 	amSets := n.alertmanagers
 	n.mtx.RUnlock()
 
-	var res []string
+	var res []*url.URL
 
 	for _, ams := range amSets {
 		ams.mtx.RLock()
@@ -364,7 +364,7 @@ func (n *Notifier) sendAll(alerts ...*model.Alert) bool {
 			defer cancel()
 
 			go func(am alertmanager) {
-				u := am.url()
+				u := am.url().String()
 
 				if err := n.sendOne(ctx, ams.client, u, b); err != nil {
 					log.With("alertmanager", u).With("count", len(alerts)).Errorf("Error sending alerts: %s", err)
@@ -412,20 +412,19 @@ func (n *Notifier) Stop() {
 
 // alertmanager holds Alertmanager endpoint information.
 type alertmanager interface {
-	url() string
+	url() *url.URL
 }
 
 type alertmanagerLabels model.LabelSet
 
 const pathLabel = "__alerts_path__"
 
-func (a alertmanagerLabels) url() string {
-	u := &url.URL{
+func (a alertmanagerLabels) url() *url.URL {
+	return &url.URL{
 		Scheme: string(a[model.SchemeLabel]),
 		Host:   string(a[model.AddressLabel]),
 		Path:   string(a[pathLabel]),
 	}
-	return u.String()
 }
 
 // alertmanagerSet contains a set of Alertmanagers discovered via a group of service
@@ -476,7 +475,7 @@ func (s *alertmanagerSet) Sync(tgs []*config.TargetGroup) {
 	seen := map[string]struct{}{}
 
 	for _, am := range all {
-		us := am.url()
+		us := am.url().String()
 		if _, ok := seen[us]; ok {
 			continue
 		}

notifier/notifier_test.go

@@ -19,6 +19,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"reflect"
 	"testing"
 	"time"
@@ -415,6 +416,10 @@ type alertmanagerMock struct {
 	urlf func() string
 }
 
-func (a alertmanagerMock) url() string {
-	return a.urlf()
+func (a alertmanagerMock) url() *url.URL {
+	u, err := url.Parse(a.urlf())
+	if err != nil {
+		panic(err)
+	}
+	return u
 }

web/api/v1/api.go

@@ -19,6 +19,7 @@ import (
 	"fmt"
 	"math"
 	"net/http"
+	"net/url"
 	"sort"
 	"strconv"
 	"time"
@@ -74,7 +75,7 @@ type targetRetriever interface {
 }
 
 type alertmanagerRetriever interface {
-	Alertmanagers() []string
+	Alertmanagers() []*url.URL
 }
 
 type response struct {
@@ -430,8 +431,8 @@ func (api *API) alertmanagers(r *http.Request) (interface{}, *apiError) {
 	urls := api.alertmanagerRetriever.Alertmanagers()
 	ams := &AlertmanagerDiscovery{ActiveAlertmanagers: make([]*AlertmanagerTarget, len(urls))}
 
-	for i := range urls {
-		ams.ActiveAlertmanagers[i] = &AlertmanagerTarget{URL: urls[i]}
+	for i, url := range urls {
+		ams.ActiveAlertmanagers[i] = &AlertmanagerTarget{URL: url.String()}
 	}
 
 	return ams, nil

web/api/v1/api_test.go

@@ -39,9 +39,9 @@ func (f targetRetrieverFunc) Targets() []*retrieval.Target {
 	return f()
 }
 
-type alertmanagerRetrieverFunc func() []string
+type alertmanagerRetrieverFunc func() []*url.URL
 
-func (f alertmanagerRetrieverFunc) Alertmanagers() []string {
+func (f alertmanagerRetrieverFunc) Alertmanagers() []*url.URL {
 	return f()
 }
 
@@ -77,8 +77,12 @@ func TestEndpoints(t *testing.T) {
 		}
 	})
 
-	ar := alertmanagerRetrieverFunc(func() []string {
-		return []string{"http://alertmanager.example.com:8080/api/v1/alerts"}
+	ar := alertmanagerRetrieverFunc(func() []*url.URL {
+		return []*url.URL{{
+			Scheme: "http",
+			Host:   "alertmanager.example.com:8080",
+			Path:   "/api/v1/alerts",
+		}}
 	})
 
 	api := &API{

web/ui/templates/status.html

@@ -54,7 +54,8 @@
         </tr>
         {{range .Alertmanagers}}
         <tr>
-          <td>{{.}}</td>
+          {{/* Alertmanager URLs always have Scheme, Host and Path set */}}
+          <td>{{.Scheme}}://<a href="{{.Scheme}}://{{.Host}}">{{.Host}}</a>{{.Path}}</td>
         </tr>
         {{end}}
       </tbody>

web/web.go

@@ -347,7 +347,7 @@ func (h *Handler) status(w http.ResponseWriter, r *http.Request) {
 		Birth         time.Time
 		CWD           string
 		Version       *PrometheusVersion
-		Alertmanagers []string
+		Alertmanagers []*url.URL
 	}{
 		Birth:         h.birth,
 		CWD:           h.cwd,