From ae7b097630c6bd6d8c067af287826ba42c71c4e0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Mierzwa?= <l.mierzwa@gmail.com>
Date: Thu, 5 Dec 2019 19:10:56 +0000
Subject: [PATCH] fix(backend): correct pre-release version parsing for
 alertmanager upstreams

Fixes #1229
---
 internal/alertmanager/mapper_test.go | 40 ++++++++++++++++++++++++++++
 internal/mapper/mapper.go            | 12 ++++++---
 2 files changed, 49 insertions(+), 3 deletions(-)
 create mode 100644 internal/alertmanager/mapper_test.go

diff --git a/internal/alertmanager/mapper_test.go b/internal/alertmanager/mapper_test.go
new file mode 100644
index 000000000..b81c55ba0
--- /dev/null
+++ b/internal/alertmanager/mapper_test.go
@@ -0,0 +1,40 @@
+package alertmanager
+
+import (
+	"testing"
+
+	"github.com/prymitive/karma/internal/mapper"
+)
+
+func TestGetAlertMapper(t *testing.T) {
+	versions := []string{
+		"0.4.0",
+		"0.4.1",
+		"0.4.99",
+		"0.5.0-alpha.0",
+		"0.5.0-beta.0",
+		"0.10",
+		"0.10.11",
+		"0.15.0-rc.3",
+		"0.17.0",
+		"0.20.0-rc.0",
+		"0.20.0-rc.0-2",
+	}
+
+	for _, version := range versions {
+		_, err := mapper.GetAlertMapper(version)
+		if err != nil {
+			t.Errorf("mapper.GetAlertMapper(%s) returned error: %s", version, err)
+		}
+
+		_, err = mapper.GetSilenceMapper(version)
+		if err != nil {
+			t.Errorf("mapper.GetSilenceMapper(%s) returned error: %s", version, err)
+		}
+
+		_, err = mapper.GetStatusMapper(version)
+		if err != nil {
+			t.Errorf("mapper.GetStatusMapper(%s) returned error: %s", version, err)
+		}
+	}
+}
diff --git a/internal/mapper/mapper.go b/internal/mapper/mapper.go
index 2c490cca3..c08e21b2d 100644
--- a/internal/mapper/mapper.go
+++ b/internal/mapper/mapper.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"strings"
 	"time"
 
 	"github.com/prymitive/karma/internal/models"
@@ -50,10 +51,15 @@ func RegisterAlertMapper(m AlertMapper) {
 	alertMappers = append(alertMappers, m)
 }
 
+func fixSemVersion(version string) string {
+	// https://github.com/Masterminds/semver/issues/135
+	return strings.SplitN(version, "-", 2)[0]
+}
+
 // GetAlertMapper returns mapper for given version
 func GetAlertMapper(version string) (AlertMapper, error) {
 	for _, m := range alertMappers {
-		if m.IsSupported(version) {
+		if m.IsSupported(fixSemVersion(version)) {
 			return m, nil
 		}
 	}
@@ -69,7 +75,7 @@ func RegisterSilenceMapper(m SilenceMapper) {
 // GetSilenceMapper returns mapper for given version
 func GetSilenceMapper(version string) (SilenceMapper, error) {
 	for _, m := range silenceMappers {
-		if m.IsSupported(version) {
+		if m.IsSupported(fixSemVersion(version)) {
 			return m, nil
 		}
 	}
@@ -85,7 +91,7 @@ func RegisterStatusMapper(m StatusMapper) {
 // GetStatusMapper returns mapper for given version
 func GetStatusMapper(version string) (StatusMapper, error) {
 	for _, m := range statusMappers {
-		if m.IsSupported(version) {
+		if m.IsSupported(fixSemVersion(version)) {
 			return m, nil
 		}
 	}