feat: Add custom structure configuration capability

Includes capability to watch a section of the custom configuration for changes when using the Configuration Provider

closes #557 & #578

Signed-off-by: lenny <[email protected]>

app-service-template/Attribution.txt

@@ -175,4 +175,7 @@ golang.org/x/sys (Unspecified) https://github.com/golang/sys
 https://github.com/golang/sys/blob/master/LICENSE
 
 stretchr/objx (MIT) https://github.com/stretchr/objx
-https://github.com/stretchr/objx/blob/master/LICENSE
+https://github.com/stretchr/objx/blob/master/LICENSE
+
+github.com/gorilla/websocket (BSD-2) https://github.com/gorilla/websocket
+https://github.com/gorilla/websocket/blob/master/LICENSE

app-service-template/config/configuration.go

@@ -0,0 +1,106 @@
+// TODO: Change Copyright to your company if open sourcing or remove header
+//
+// Copyright (c) 2021 Intel Corporation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package config
+
+import (
+	"reflect"
+
+	"github.com/edgexfoundry/go-mod-core-contracts/v2/clients/logger"
+)
+
+// TODO: Define your structured custom configuration types. Must be wrapped with an outer struct with
+//       single element that matches the top level custom configuration element in your configuration.toml file,
+//       'AppCustom' in this example. Replace this example with your configuration structure or
+//       remove this file if not using structured custom configuration.
+type ServiceConfig struct {
+	AppCustom AppCustomConfig
+}
+
+// AppCustomConfig is example of service's custom structured configuration that is specified in the service's
+// configuration.toml file and Configuration Provider (aka Consul), if enabled.
+type AppCustomConfig struct {
+	ResourceNames string
+	SomeValue     int
+	SomeService   HostInfo
+}
+
+// HostInfo is example struct for defining connection information for external service
+type HostInfo struct {
+	Host     string
+	Port     int
+	Protocol string
+}
+
+// TODO: Update using your Custom configuration type.
+// UpdateFromRaw updates the service's full configuration from raw data received from
+// the Service Provider.
+func (c *ServiceConfig) UpdateFromRaw(rawConfig interface{}) bool {
+	configuration, ok := rawConfig.(*ServiceConfig)
+	if !ok {
+		return false //errors.New("unable to cast raw config to type 'ServiceConfig'")
+	}
+
+	*c = *configuration
+
+	return true
+}
+
+// TODO: Update using your Custom configuration 'writeable' type or remove if not using ListenForCustomConfigChanges
+// UpdateWritableFromRaw updates the service's writable configuration from raw data received from
+// the Service Provider. Must implement if using ListenForCustomConfigChanges, otherwise this can be removed.
+func (ac *AppCustomConfig) UpdateWritableFromRaw(rawWritableConfig interface{}) bool {
+	appCustom, ok := rawWritableConfig.(*AppCustomConfig)
+	if !ok {
+		return false //errors.New("unable to cast raw writeable config to type 'AppCustomConfig'")
+	}
+
+	*ac = *appCustom
+
+	return true
+}
+
+// WaitForCustomConfigChanges waits for indication that the custom configuration section has been updated and then process
+// the changes as needed
+// TODO: Update to use your custom configuration section that you want to be writable (i.e. runtime changes from Consul)
+//       or remove if not using custom configuration section or writable custom configuration.
+func (ac *AppCustomConfig) WaitForCustomConfigChanges(configChanged chan bool, lc logger.LoggingClient) {
+	previous := *ac // Copy for change detection
+
+	go func() {
+		for {
+			select {
+			case <-configChanged:
+				// TODO: Process the changed configuration.
+				//       Must keep a previous copy of the configuration to determine what has changed.
+				//		 Replace the examples below with your appropriate processing logic.
+				switch {
+				case previous.SomeValue != ac.SomeValue:
+					lc.Infof("AppCustom.SomeValue changed to: %d", ac.SomeValue)
+				case previous.ResourceNames != ac.ResourceNames:
+					lc.Infof("AppCustom.ResourceNames changed to: %s", ac.ResourceNames)
+				case !reflect.DeepEqual(previous.SomeService, ac.SomeService):
+					lc.Infof("AppCustom.SomeService changed to: %v", ac.SomeService)
+				default:
+					lc.Info("No changes detected")
+				}
+
+				previous = *ac
+			}
+		}
+	}()
+}

app-service-template/main.go

@@ -20,9 +20,12 @@ package main
 import (
 	"os"
 
+	"github.com/edgexfoundry/go-mod-core-contracts/v2/clients/logger"
+
 	"github.com/edgexfoundry/app-functions-sdk-go/v2/pkg"
 	"github.com/edgexfoundry/app-functions-sdk-go/v2/pkg/interfaces"
 	"github.com/edgexfoundry/app-functions-sdk-go/v2/pkg/transforms"
+	"new-app-service/config"
 
 	"new-app-service/functions"
 )
@@ -31,45 +34,75 @@ const (
 	serviceKey = "new-app-service"
 )
 
+// TODO: Define your app's struct
+type myApp struct {
+	service       interfaces.ApplicationService
+	lc            logger.LoggingClient
+	serviceConfig *config.ServiceConfig
+	configChanged chan bool
+}
+
 func main() {
 	// TODO: See https://docs.edgexfoundry.org/1.3/microservices/application/ApplicationServices/
 	//       for documentation on application services.
-
-	code := CreateAndRunService(serviceKey, pkg.NewAppService)
+	app := myApp{}
+	code := app.CreateAndRunAppService(serviceKey, pkg.NewAppService)
 	os.Exit(code)
 }
 
-// CreateAndRunService wraps what would normally be in main() so that it can be unit tested
-func CreateAndRunService(serviceKey string, newServiceFactory func(string) (interfaces.ApplicationService, bool)) int {
-	service, ok := newServiceFactory(serviceKey)
+// CreateAndRunAppService wraps what would normally be in main() so that it can be unit tested
+func (app *myApp) CreateAndRunAppService(serviceKey string, newServiceFactory func(string) (interfaces.ApplicationService, bool)) int {
+	var ok bool
+	app.service, ok = newServiceFactory(serviceKey)
 	if !ok {
 		return -1
 	}
 
-	lc := service.LoggingClient()
+	app.lc = app.service.LoggingClient()
+
+	// TODO: Replace with retrieving your custom ApplicationSettings from configuration or
+	//       remove if not using AppSetting configuration section.
+	deviceNames, err := app.service.GetAppSettingStrings("DeviceNames")
+	if err != nil {
+		app.lc.Errorf("failed to retrieve DeviceNames from configuration: %s", err.Error())
+		return -1
+	}
+
+	// TODO: Change to use your service's custom configuration
+	//       or remove if not using custom configuration capability
+	app.serviceConfig = &config.ServiceConfig{}
+	if err := app.service.LoadCustomConfig(app.serviceConfig, "AppCustom"); err != nil {
+		app.lc.Errorf("failed load custom configuration: %s", err.Error())
+		return -1
+	}
+
+	// TODO: Remove after demos and testing
+	app.lc.Infof("ServiceConfig config is: %v", app.serviceConfig)
 
-	// TODO: Replace with retrieving your custom ApplicationSettings from configuration
-	deviceNames, err := service.GetAppSettingStrings("DeviceNames")
+	// TODO: Remove if not using writable custom configuration
+	configChanged := make(chan bool)
+	err = app.service.ListenForCustomConfigChanges(&app.serviceConfig.AppCustom, "AppCustom", configChanged)
 	if err != nil {
-		lc.Errorf("failed to retrieve DeviceNames from configuration: %s", err.Error())
+		app.lc.Errorf("unable to watch custom writable configuration: %s", err.Error())
 		return -1
 	}
+	app.serviceConfig.AppCustom.WaitForCustomConfigChanges(configChanged, app.lc)
 
 	// TODO: Replace below functions with built in and/or your custom functions for your use case.
 	//       See https://docs.edgexfoundry.org/1.3/microservices/application/BuiltIn/ for list of built-in functions
 	sample := functions.NewSample()
-	err = service.SetFunctionsPipeline(
+	err = app.service.SetFunctionsPipeline(
 		transforms.NewFilterFor(deviceNames).FilterByDeviceName,
 		sample.LogEventDetails,
 		sample.ConvertEventToXML,
 		sample.OutputXML)
 	if err != nil {
-		lc.Errorf("SetFunctionsPipeline returned error: %s", err.Error())
+		app.lc.Errorf("SetFunctionsPipeline returned error: %s", err.Error())
 		return -1
 	}
 
-	if err := service.MakeItRun(); err != nil {
-		lc.Errorf("MakeItRun returned error: %s", err.Error())
+	if err := app.service.MakeItRun(); err != nil {
+		app.lc.Errorf("MakeItRun returned error: %s", err.Error())
 		return -1
 	}
 

app-service-template/main_test.go

@@ -31,7 +31,7 @@ import (
 
 // This is an example of how to test the code that would typically be in the main() function use mocks
 // Not to helpful for a simple main() , but can be if the main() has more complexity that should be unit tested
-// TODO: add/update tests for your customized CreateAndRunService or remove for simple main()
+// TODO: add/update tests for your customized CreateAndRunAppService or remove for simple main()
 
 func TestCreateAndRunService_Success(t *testing.T) {
 	mockFactory := func(_ string) (interfaces.ApplicationService, bool) {
@@ -41,22 +41,28 @@ func TestCreateAndRunService_Success(t *testing.T) {
 			Return([]string{"Random-Boolean-Device, Random-Integer-Device"}, nil)
 		mockAppService.On("SetFunctionsPipeline", mock.Anything, mock.Anything, mock.Anything, mock.Anything).
 			Return(nil)
+		mockAppService.On("LoadCustomConfig", mock.Anything, mock.Anything, mock.Anything).
+			Return(nil)
+		mockAppService.On("ListenForCustomConfigChanges", mock.Anything, mock.Anything, mock.Anything, mock.Anything).
+			Return(nil)
 		mockAppService.On("MakeItRun").Return(nil)
 
 		return mockAppService, true
 	}
 
+	app := myApp{}
 	expected := 0
-	actual := CreateAndRunService("TestKey", mockFactory)
+	actual := app.CreateAndRunAppService("TestKey", mockFactory)
 	assert.Equal(t, expected, actual)
 }
 
 func TestCreateAndRunService_NewService_Failed(t *testing.T) {
 	mockFactory := func(_ string) (interfaces.ApplicationService, bool) {
 		return nil, false
 	}
+	app := myApp{}
 	expected := -1
-	actual := CreateAndRunService("TestKey", mockFactory)
+	actual := app.CreateAndRunAppService("TestKey", mockFactory)
 	assert.Equal(t, expected, actual)
 }
 
@@ -70,8 +76,9 @@ func TestCreateAndRunService_GetAppSettingStrings_Failed(t *testing.T) {
 		return mockAppService, true
 	}
 
+	app := myApp{}
 	expected := -1
-	actual := CreateAndRunService("TestKey", mockFactory)
+	actual := app.CreateAndRunAppService("TestKey", mockFactory)
 	assert.Equal(t, expected, actual)
 }
 
@@ -81,14 +88,19 @@ func TestCreateAndRunService_SetFunctionsPipeline_Failed(t *testing.T) {
 		mockAppService.On("LoggingClient").Return(logger.NewMockClient())
 		mockAppService.On("GetAppSettingStrings", "DeviceNames").
 			Return([]string{"Random-Boolean-Device, Random-Integer-Device"}, nil)
+		mockAppService.On("LoadCustomConfig", mock.Anything, mock.Anything, mock.Anything).
+			Return(nil)
+		mockAppService.On("ListenForCustomConfigChanges", mock.Anything, mock.Anything, mock.Anything, mock.Anything).
+			Return(nil)
 		mockAppService.On("SetFunctionsPipeline", mock.Anything, mock.Anything, mock.Anything, mock.Anything).
 			Return(fmt.Errorf("Failed"))
 
 		return mockAppService, true
 	}
 
+	app := myApp{}
 	expected := -1
-	actual := CreateAndRunService("TestKey", mockFactory)
+	actual := app.CreateAndRunAppService("TestKey", mockFactory)
 	assert.Equal(t, expected, actual)
 }
 
@@ -98,14 +110,19 @@ func TestCreateAndRunService_MakeItRun_Failed(t *testing.T) {
 		mockAppService.On("LoggingClient").Return(logger.NewMockClient())
 		mockAppService.On("GetAppSettingStrings", "DeviceNames").
 			Return([]string{"Random-Boolean-Device, Random-Integer-Device"}, nil)
+		mockAppService.On("LoadCustomConfig", mock.Anything, mock.Anything, mock.Anything).
+			Return(nil)
+		mockAppService.On("ListenForCustomConfigChanges", mock.Anything, mock.Anything, mock.Anything, mock.Anything).
+			Return(nil)
 		mockAppService.On("SetFunctionsPipeline", mock.Anything, mock.Anything, mock.Anything, mock.Anything).
 			Return(nil)
 		mockAppService.On("MakeItRun").Return(fmt.Errorf("Failed"))
 
 		return mockAppService, true
 	}
 
+	app := myApp{}
 	expected := -1
-	actual := CreateAndRunService("TestKey", mockFactory)
+	actual := app.CreateAndRunAppService("TestKey", mockFactory)
 	assert.Equal(t, expected, actual)
 }

app-service-template/res/configuration.toml

@@ -57,7 +57,7 @@ RetryWaitPeriod = "1s"
   AuthType = 'X-Vault-Token'
 
 [Clients]
-  [Clients.CoreData]
+  [Clients.edgex-core-data]
   Protocol = 'http'
   Host = 'localhost'
   Port = 48080
@@ -102,10 +102,21 @@ PublishTopic="event-xml"  #TODO: remove if service is NOT publishing back to the
 #    ConnectTimeout = "30" # Seconds
 #    SkipCertVerify = "false"
 
-
-[ApplicationSettings]
-# TODO: Add custom settings needed by your app service
+# TODO: Add custom settings needed by your app service or remove if you don't have any settings.
 # This can be any Key/Value pair you need.
 # For more details see: https://docs.edgexfoundry.org/1.3/microservices/application/GeneralAppServiceConfig/#application-settings
 # Example that works with devices from the Virtual Device service:
+[ApplicationSettings]
 DeviceNames = "Random-Boolean-Device, Random-Integer-Device, Random-UnsignedInteger-Device, Random-Float-Device, Random-Binary-Device"
+
+# TODO: Replace this section with your actual structured custom configuration section
+#       or remove if you don't have a need for structured custom configuration
+# This can be any structure you need, but it can not contain slices. Use a maps instead of slices.
+# For more details see: https://docs.edgexfoundry.org/2.0/microservices/application/GeneralAppServiceConfig/#custom-configuration
+[AppCustom]
+ResourceNames = "Boolean, Int32, Uint32, Float32, Binary"
+SomeValue = 123
+  [AppCustom.SomeService]
+  Host = "localhost"
+  Port = 9080
+  Protocol = "http"

go.mod

@@ -5,14 +5,15 @@ go 1.15
 require (
 	bitbucket.org/bertimus9/systemstat v0.0.0-20180207000608-0eeff89b0690
 	github.com/diegoholiveira/jsonlogic v1.0.1-0.20200220175622-ab7989be08b9
-	github.com/eclipse/paho.mqtt.golang v1.2.0
-	github.com/edgexfoundry/go-mod-bootstrap/v2 v2.0.0-dev.14
+	github.com/eclipse/paho.mqtt.golang v1.3.2
+	github.com/edgexfoundry/go-mod-bootstrap/v2 v2.0.0-dev.18
 	github.com/edgexfoundry/go-mod-core-contracts/v2 v2.0.0-dev.54
-	github.com/edgexfoundry/go-mod-messaging/v2 v2.0.0-dev.3
+	github.com/edgexfoundry/go-mod-messaging/v2 v2.0.0-dev.6
 	github.com/edgexfoundry/go-mod-registry/v2 v2.0.0-dev.3
 	github.com/fxamacker/cbor/v2 v2.2.0
 	github.com/gomodule/redigo v2.0.0+incompatible
 	github.com/google/uuid v1.2.0
 	github.com/gorilla/mux v1.8.0
 	github.com/stretchr/testify v1.7.0
 )
+