fix: handle single aud string claim, extract en/decoder interface, comments (#51)

* en/decoding abstraction

* some comments

* fix token validation and error messages

* fix: audience mapping (single aud string)

* fix tests with VerifyIdToken

* reformat imports

* go mod tidy

* Update pkg/oidc/authorization.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* Update pkg/oidc/authorization.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* Update pkg/op/authrequest_test.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* fix capitalization

Co-authored-by: Silvan <silvan.reusser@gmail.com>

pkg/op/mock/authorizer.mock.go

@@ -7,8 +7,8 @@ package mock
 import (
 	op "github.com/caos/oidc/pkg/op"
 	rp "github.com/caos/oidc/pkg/rp"
+	utils "github.com/caos/oidc/pkg/utils"
 	gomock "github.com/golang/mock/gomock"
-	schema "github.com/gorilla/schema"
 	reflect "reflect"
 )
 
@@ -50,10 +50,10 @@ func (mr *MockAuthorizerMockRecorder) Crypto() *gomock.Call {
 }
 
 // Decoder mocks base method
-func (m *MockAuthorizer) Decoder() *schema.Decoder {
+func (m *MockAuthorizer) Decoder() utils.Decoder {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "Decoder")
-	ret0, _ := ret[0].(*schema.Decoder)
+	ret0, _ := ret[0].(utils.Decoder)
 	return ret0
 }
 
@@ -64,10 +64,10 @@ func (mr *MockAuthorizerMockRecorder) Decoder() *gomock.Call {
 }
 
 // Encoder mocks base method
-func (m *MockAuthorizer) Encoder() *schema.Encoder {
+func (m *MockAuthorizer) Encoder() utils.Encoder {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "Encoder")
-	ret0, _ := ret[0].(*schema.Encoder)
+	ret0, _ := ret[0].(utils.Encoder)
 	return ret0
 }
 

pkg/op/mock/authorizer.mock.impl.go

@@ -69,6 +69,9 @@ type Verifier struct{}
 func (v *Verifier) Verify(ctx context.Context, accessToken, idToken string) (*oidc.IDTokenClaims, error) {
 	return nil, nil
 }
+func (v *Verifier) VerifyIDToken(ctx context.Context, idToken string) (*oidc.IDTokenClaims, error) {
+	return nil, nil
+}
 
 type Sig struct{}
 

pkg/op/mock/client.go

@@ -1,12 +1,12 @@
 package mock
 
 import (
-	"github.com/caos/oidc/pkg/oidc"
 	"testing"
 
-	gomock "github.com/golang/mock/gomock"
+	"github.com/golang/mock/gomock"
 
-	op "github.com/caos/oidc/pkg/op"
+	"github.com/caos/oidc/pkg/oidc"
+	"github.com/caos/oidc/pkg/op"
 )
 
 func NewClient(t *testing.T) op.Client {