[FAB-11173] FabToken Validation Plugin

This change-set in accordance to FAB-11173 does the following:
Under core/handlers/validation/builtin, a new skeleton implementation of
PluginFactory and Plugin will be introduced.
The new FabtokenPluginFactory will return instances of the
new FabTokenValidation whose default implementation returns no error.
Tests have been included to verify the above behaviour.

Change-Id: I869e5f492eace02ceb843d7e6366a768464ba746
Signed-off-by: Angelo De Caro <adc@zurich.ibm.com>

Author: adecaro

core/handlers/validation/token/validation.go

@@ -0,0 +1,30 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package token
+
+import (
+	"github.com/hyperledger/fabric/core/handlers/validation/api"
+	"github.com/hyperledger/fabric/protos/common"
+)
+
+type ValidationFactory struct {
+}
+
+func (*ValidationFactory) New() validation.Plugin {
+	return &ValidationPlugin{}
+}
+
+type ValidationPlugin struct {
+}
+
+func (v *ValidationPlugin) Init(dependencies ...validation.Dependency) error {
+	return nil
+}
+
+func (v *ValidationPlugin) Validate(block *common.Block, namespace string, txPosition int, actionPosition int, contextData ...validation.ContextDatum) error {
+	return nil
+}

core/handlers/validation/token/validation_test.go

@@ -0,0 +1,32 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package token_test
+
+import (
+	"testing"
+
+	"github.com/hyperledger/fabric/core/handlers/validation/token"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestValidationFactory_New(t *testing.T) {
+	factory := &token.ValidationFactory{}
+	plugin := factory.New()
+	assert.NotNil(t, plugin)
+}
+
+func TestValidation_Validate(t *testing.T) {
+	factory := &token.ValidationFactory{}
+	plugin := factory.New()
+
+	err := plugin.Init()
+	assert.NoError(t, err)
+
+	// Validate returns nil, no matter what!
+	err = plugin.Validate(nil, "", 0, 0, nil)
+	assert.NoError(t, err)
+}