From f54c8157efd7f21693880fc1d3af428073c753eb Mon Sep 17 00:00:00 2001
From: Matthew McGinn <mcginn@hudson-trading.com>
Date: Tue, 5 Dec 2017 15:12:26 -0500
Subject: [PATCH 1/2] Adding check for webhook's URL formatting Since
 alertmanager will fail silently when trying to send to a schemaless URL,
 provide a way to check that a URL is properly formatted in alertmanager

---
 config/notifiers.go      |  9 +++++++++
 config/notifiers_test.go | 17 +++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/config/notifiers.go b/config/notifiers.go
index 5193100d11..cdfe4776c7 100644
--- a/config/notifiers.go
+++ b/config/notifiers.go
@@ -15,6 +15,7 @@ package config
 
 import (
 	"fmt"
+	"net/url"
 	"strings"
 	"time"
 )
@@ -292,6 +293,14 @@ func (c *WebhookConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	if c.URL == "" {
 		return fmt.Errorf("missing URL in webhook config")
 	}
+	url, err := url.Parse(c.URL)
+	if err != nil {
+		return err
+	}
+	if url.Scheme != "https" && url.Scheme != "http" {
+		return fmt.Errorf("non-absolute URL in webhook config")
+	}
+	c.URL = url.String()
 	return checkOverflow(c.XXX, "webhook config")
 }
 
diff --git a/config/notifiers_test.go b/config/notifiers_test.go
index b436f77e2a..767b875e18 100644
--- a/config/notifiers_test.go
+++ b/config/notifiers_test.go
@@ -110,6 +110,23 @@ url: ''
 	}
 }
 
+func TestWebhookURLIsAbsolute(t *testing.T) {
+	in := `
+url: 'localhost:9093'
+`
+	var cfg WebhookConfig
+	err := yaml.Unmarshal([]byte(in), &cfg)
+
+	expected := "non-absolute URL in webhook config"
+
+	if err == nil {
+		t.Fatalf("no error returned, expected:\n%v", expected)
+	}
+	if err.Error() != expected {
+		t.Errorf("\nexpected:\n%v\ngot:\n%v", expected, err.Error())
+	}
+}
+
 func TestOpsGenieAPIKeyIsPresent(t *testing.T) {
 	in := `
 api_key: ''

From ea444f053c7e869644f099b451b69e7e23c9a128 Mon Sep 17 00:00:00 2001
From: Matthew McGinn <mamcgi@gmail.com>
Date: Thu, 7 Dec 2017 08:01:21 -0500
Subject: [PATCH 2/2] updating error message as requested

---
 config/notifiers.go      | 2 +-
 config/notifiers_test.go | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/config/notifiers.go b/config/notifiers.go
index cdfe4776c7..16bf320c8f 100644
--- a/config/notifiers.go
+++ b/config/notifiers.go
@@ -298,7 +298,7 @@ func (c *WebhookConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		return err
 	}
 	if url.Scheme != "https" && url.Scheme != "http" {
-		return fmt.Errorf("non-absolute URL in webhook config")
+		return fmt.Errorf("scheme required for webhook url")
 	}
 	c.URL = url.String()
 	return checkOverflow(c.XXX, "webhook config")
diff --git a/config/notifiers_test.go b/config/notifiers_test.go
index 767b875e18..e0b79dc00b 100644
--- a/config/notifiers_test.go
+++ b/config/notifiers_test.go
@@ -117,7 +117,7 @@ url: 'localhost:9093'
 	var cfg WebhookConfig
 	err := yaml.Unmarshal([]byte(in), &cfg)
 
-	expected := "non-absolute URL in webhook config"
+	expected := "scheme required for webhook url"
 
 	if err == nil {
 		t.Fatalf("no error returned, expected:\n%v", expected)