add notes about TrustServiceUrl (#2044)

* add notes about TrustServiceUrl

* added proactive docs to Proactive Teams sample

Author: mdrichardson

samples/csharp_dotnetcore/16.proactive-messages/Controllers/NotifyController.cs

@@ -55,6 +55,8 @@ public async Task<IActionResult> Get()
 
         private async Task BotCallback(ITurnContext turnContext, CancellationToken cancellationToken)
         {
+            // If you encounter permission-related errors when sending this message, see
+            // https://aka.ms/BotTrustServiceUrl
             await turnContext.SendActivityAsync("proactive hello");
         }
     }

samples/csharp_dotnetcore/16.proactive-messages/README.md

@@ -86,6 +86,10 @@ In order to send a proactive message using Bot Framework, the bot must first cap
 
 To send proactive messages, acquire a conversation reference, then use `adapter.continueConversation()` to create a TurnContext object that will allow the bot to deliver the new outgoing message.
 
+### Avoiding Permission-Related Errors
+
+You may encounter permission-related errors when sending a proactive message. This can often be mitigated by using `MicrosoftAppCredentials.TrustServiceUrl()`. See [the documentation](https://docs.microsoft.com/en-us/azure/bot-service/bot-builder-howto-proactive-message?view=azure-bot-service-4.0&tabs=csharp#avoiding-401-unauthorized-errors) for more information.
+
 ## Deploy this bot to Azure
 
 To learn more about deploying a bot to Azure, see [Deploy your bot to Azure](https://aka.ms/azuredeployment) for a complete list of deployment instructions.

samples/csharp_dotnetcore/57.teams-conversation-bot/Bots/TeamsConversationBot.cs

@@ -91,6 +91,8 @@ private async Task DeleteCardActivityAsync(ITurnContext<IMessageActivity> turnCo
             await turnContext.DeleteActivityAsync(turnContext.Activity.ReplyToId, cancellationToken);
         }
 
+        // If you encounter permission-related errors when sending this message, see
+        // https://aka.ms/BotTrustServiceUrl
         private async Task MessageAllMembersAsync(ITurnContext<IMessageActivity> turnContext, CancellationToken cancellationToken)
         {
             var teamsChannelId = turnContext.Activity.TeamsGetChannelId();

samples/csharp_dotnetcore/57.teams-conversation-bot/README.md

@@ -64,6 +64,10 @@ You can interact with this bot by sending it a message, or selecting a command f
 
 You can select an option from the command list by typing ```@TeamsConversationBot``` into the compose message area and ```What can I do?``` text above the compose area.
 
+### Avoiding Permission-Related Errors
+
+You may encounter permission-related errors when sending a proactive message. This can often be mitigated by using `MicrosoftAppCredentials.TrustServiceUrl()`. See [the documentation](https://docs.microsoft.com/en-us/azure/bot-service/bot-builder-howto-proactive-message?view=azure-bot-service-4.0&tabs=csharp#avoiding-401-unauthorized-errors) for more information.
+
 ## Deploy the bot to Azure
 
 To learn more about deploying a bot to Azure, see [Deploy your bot to Azure](https://aka.ms/azuredeployment) for a complete list of deployment instructions.

samples/javascript_nodejs/16.proactive-messages/README.md

@@ -86,6 +86,10 @@ In order to send a proactive message using Bot Framework, the bot must first cap
 
 To send proactive messages, acquire a conversation reference, then use `adapter.continueConversation()` to create a TurnContext object that will allow the bot to deliver the new outgoing message.
 
+### Avoiding Permission-Related Errors
+
+You may encounter permission-related errors when sending a proactive message. This can often be mitigated by using `MicrosoftAppCredentials.trustServiceUrl()`. See [the documentation](https://docs.microsoft.com/en-us/azure/bot-service/bot-builder-howto-proactive-message?view=azure-bot-service-4.0&tabs=javascript#avoiding-401-unauthorized-errors) for more information.
+
 ## Deploy this bot to Azure
 
 To learn more about deploying a bot to Azure, see [Deploy your bot to Azure](https://aka.ms/azuredeployment) for a complete list of deployment instructions.

samples/javascript_nodejs/16.proactive-messages/index.js

@@ -69,6 +69,8 @@ server.post('/api/messages', (req, res) => {
 server.get('/api/notify', async (req, res) => {
     for (const conversationReference of Object.values(conversationReferences)) {
         await adapter.continueConversation(conversationReference, async turnContext => {
+            // If you encounter permission-related errors when sending this message, see
+            // https://aka.ms/BotTrustServiceUrl
             await turnContext.sendActivity('proactive hello');
         });
     }

samples/javascript_nodejs/57.teams-conversation-bot/README.md

@@ -71,6 +71,10 @@ You can interact with this bot by sending it a message, or selecting a command f
 
 You can select an option from the command list by typing ```@TeamsConversationBot``` into the compose message area and ```What can I do?``` text above the compose area.
 
+### Avoiding Permission-Related Errors
+
+You may encounter permission-related errors when sending a proactive message. This can often be mitigated by using `MicrosoftAppCredentials.trustServiceUrl()`. See [the documentation](https://docs.microsoft.com/en-us/azure/bot-service/bot-builder-howto-proactive-message?view=azure-bot-service-4.0&tabs=javascript#avoiding-401-unauthorized-errors) for more information.
+
 ## Deploy the bot to Azure
 
 To learn more about deploying a bot to Azure, see [Deploy your bot to Azure](https://aka.ms/azuredeployment) for a complete list of deployment instructions.

samples/javascript_nodejs/57.teams-conversation-bot/bots/teamsConversationBot.js

@@ -112,6 +112,8 @@ class TeamsConversationBot extends TeamsActivityHandler {
         await context.deleteActivity(context.activity.replyToId);
     }
 
+    // If you encounter permission-related errors when sending this message, see
+    // https://aka.ms/BotTrustServiceUrl
     async messageAllMembersAsync(context) {
         const members = await TeamsInfo.getMembers(context);