Move StringSet to new collections package

As part of the efforts to break up the common package before disaster strikes,
a new collections package has been created. More may belong there but for now,
it only includes an implementation of StringSet.

Signed-off-by: Stephen J Day <stephen.day@docker.com>

auth/token/accesscontroller.go

@@ -14,7 +14,7 @@ import (
 	"github.com/docker/libtrust"
 
 	"github.com/docker/distribution/auth"
-	"github.com/docker/distribution/common"
+	"github.com/docker/distribution/collections"
 )
 
 // accessSet maps a typed, named resource to
@@ -241,8 +241,8 @@ func (ac *accessController) Authorized(req *http.Request, accessItems ...auth.Ac
 	}
 
 	verifyOpts := VerifyOptions{
-		TrustedIssuers:    common.NewStringSet(ac.issuer),
-		AcceptedAudiences: common.NewStringSet(ac.service),
+		TrustedIssuers:    collections.NewStringSet(ac.issuer),
+		AcceptedAudiences: collections.NewStringSet(ac.service),
 		Roots:             ac.rootCerts,
 		TrustedKeys:       ac.trustedKeys,
 	}

auth/token/token.go

@@ -14,7 +14,7 @@ import (
 	"github.com/docker/libtrust"
 
 	"github.com/docker/distribution/auth"
-	"github.com/docker/distribution/common"
+	"github.com/docker/distribution/collections"
 )
 
 const (
@@ -71,8 +71,8 @@ type Token struct {
 // VerifyOptions is used to specify
 // options when verifying a JSON Web Token.
 type VerifyOptions struct {
-	TrustedIssuers    common.StringSet
-	AcceptedAudiences common.StringSet
+	TrustedIssuers    collections.StringSet
+	AcceptedAudiences collections.StringSet
 	Roots             *x509.CertPool
 	TrustedKeys       map[string]libtrust.PublicKey
 }

auth/token/token_test.go

@@ -18,7 +18,7 @@ import (
 	"github.com/docker/libtrust"
 
 	"github.com/docker/distribution/auth"
-	"github.com/docker/distribution/common"
+	"github.com/docker/distribution/collections"
 )
 
 func makeRootKeys(numKeys int) ([]libtrust.PrivateKey, error) {
@@ -196,8 +196,8 @@ func TestTokenVerify(t *testing.T) {
 	}
 
 	verifyOps := VerifyOptions{
-		TrustedIssuers:    common.NewStringSet(issuer),
-		AcceptedAudiences: common.NewStringSet(audience),
+		TrustedIssuers:    collections.NewStringSet(issuer),
+		AcceptedAudiences: collections.NewStringSet(audience),
 		Roots:             rootPool,
 		TrustedKeys:       trustedKeys,
 	}

auth/token/util.go

@@ -5,7 +5,7 @@ import (
 	"errors"
 	"strings"
 
-	"github.com/docker/distribution/common"
+	"github.com/docker/distribution/collections"
 )
 
 // joseBase64UrlEncode encodes the given data using the standard base64 url
@@ -35,11 +35,11 @@ func joseBase64UrlDecode(s string) ([]byte, error) {
 
 // actionSet is a special type of stringSet.
 type actionSet struct {
-	common.StringSet
+	collections.StringSet
 }
 
 func newActionSet(actions ...string) actionSet {
-	return actionSet{common.NewStringSet(actions...)}
+	return actionSet{collections.NewStringSet(actions...)}
 }
 
 // Contains calls StringSet.Contains() for

collections/stringset.go

@@ -1,4 +1,4 @@
-package common
+package collections
 
 // StringSet is a useful type for looking up strings.
 type StringSet map[string]struct{}