From 1eb6c5e397434b036c19b9f2c30f195cabc496f6 Mon Sep 17 00:00:00 2001
From: Filippo Giunchedi <filippo@wikimedia.org>
Date: Wed, 28 Oct 2020 17:49:49 +0100
Subject: [PATCH] format: add string functions

---
 format.go | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/format.go b/format.go
index 386e1a6..32355fd 100644
--- a/format.go
+++ b/format.go
@@ -18,6 +18,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"log"
+	"strings"
 	"text/template"
 
 	promtmpl "github.com/prometheus/alertmanager/template"
@@ -29,7 +30,13 @@ type Formatter struct {
 }
 
 func NewFormatter(config *Config) (*Formatter, error) {
-	tmpl, err := template.New("msg").Parse(config.MsgTemplate)
+	funcMap := template.FuncMap{
+		"ToUpper": strings.ToUpper,
+		"ToLower": strings.ToLower,
+		"Join":    strings.Join,
+	}
+
+	tmpl, err := template.New("msg").Funcs(funcMap).Parse(config.MsgTemplate)
 	if err != nil {
 		return nil, err
 	}