From dfc63b6bdf0c6cf7bfddbf8f40793249807755ea Mon Sep 17 00:00:00 2001
From: Hidde Beydals <hello@hidde.co>
Date: Wed, 10 Apr 2019 11:24:35 +0200
Subject: [PATCH] Make `regex` an alias of `regexp` tag filter type

The word `regex` seems to be a common alias of `regexp`, so people
often use this and are left with confusion when Flux does not adhere
to what they configured.

Make it an alias to better live up to people their expectations.
---
 policy/pattern.go      | 20 +++++++++++++-------
 policy/pattern_test.go |  8 +++++++-
 site/fluxctl.md        |  1 +
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/policy/pattern.go b/policy/pattern.go
index c89864767..56380ab05 100644
--- a/policy/pattern.go
+++ b/policy/pattern.go
@@ -1,17 +1,19 @@
 package policy
 
 import (
+	"regexp"
+	"strings"
+
 	"github.com/Masterminds/semver"
 	"github.com/ryanuber/go-glob"
 	"github.com/weaveworks/flux/image"
-	"strings"
-	"regexp"
 )
 
 const (
-	globPrefix   = "glob:"
-	semverPrefix = "semver:"
-	regexpPrefix = "regexp:"
+	globPrefix      = "glob:"
+	semverPrefix    = "semver:"
+	regexpPrefix    = "regexp:"
+	regexpAltPrefix = "regex:"
 )
 
 var (
@@ -43,8 +45,8 @@ type SemverPattern struct {
 
 // RegexpPattern matches by regular expression.
 type RegexpPattern struct {
-	pattern	string // pattern without prefix
-	regexp	*regexp.Regexp
+	pattern string // pattern without prefix
+	regexp  *regexp.Regexp
 }
 
 // NewPattern instantiates a Pattern according to the prefix
@@ -60,6 +62,10 @@ func NewPattern(pattern string) Pattern {
 		pattern = strings.TrimPrefix(pattern, regexpPrefix)
 		r, _ := regexp.Compile(pattern)
 		return RegexpPattern{pattern, r}
+	case strings.HasPrefix(pattern, regexpAltPrefix):
+		pattern = strings.TrimPrefix(pattern, regexpAltPrefix)
+		r, _ := regexp.Compile(pattern)
+		return RegexpPattern{pattern, r}
 	default:
 		return GlobPattern(strings.TrimPrefix(pattern, globPrefix))
 	}
diff --git a/policy/pattern_test.go b/policy/pattern_test.go
index 35678b42f..aeb8f25f2 100644
--- a/policy/pattern_test.go
+++ b/policy/pattern_test.go
@@ -1,9 +1,9 @@
 package policy
 
 import (
+	"fmt"
 	"testing"
 
-	"fmt"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -106,6 +106,12 @@ func TestRegexpPattern_Matches(t *testing.T) {
 			true:    []string{"foo", "BAR", "fooBAR"},
 			false:   []string{"1", "foo-1"},
 		},
+		{
+			name:    "regex",
+			pattern: `regex:^\w{7}(?:\w)?$`,
+			true:    []string{"af14eb2", "bb73ed94", "946427ff"},
+			false:   []string{"1", "foo", "946427ff-foo"},
+		},
 	} {
 		pattern := NewPattern(tt.pattern)
 		assert.IsType(t, RegexpPattern{}, pattern)
diff --git a/site/fluxctl.md b/site/fluxctl.md
index c37a1515e..68fa6d19b 100644
--- a/site/fluxctl.md
+++ b/site/fluxctl.md
@@ -536,6 +536,7 @@ If your images have complex tags you can filter by regular expression:
 fluxctl policy --workload=default:deployment/helloworld --tag-all='regexp:^([a-zA-Z]+)$'
 ```
 
+Instead of `regexp` it is also possible to use its alias `regex`.
 Please bear in mind that if you want to match the whole tag,
 you must bookend your pattern with `^` and `$`.