fix: Add counter to onError trigger to break possible loops

libraries/botbuilder-dialogs-adaptive-testing/tests/conditionals.test.js

@@ -44,4 +44,12 @@ describe('ConditionalsTests', function () {
     it('OnRepromptDialog', async function () {
         await TestUtils.runTestScript(resourceExplorer, 'ConditionalsTests_OnRepromptDialog');
     });
+
+    it('OnError loop limit', async function () {
+        await TestUtils.runTestScript(resourceExplorer, 'ConditionalsTests_OnErrorLoop');
+    });
+
+    it('OnError default loop limit', async function () {
+        await TestUtils.runTestScript(resourceExplorer, 'ConditionalsTests_OnErrorLoopDefaultLimit');
+    });
 });

libraries/botbuilder-dialogs-adaptive-testing/tests/resources/ConditionalsTests/ConditionalsTests_OnErrorLoop.test.dialog

@@ -0,0 +1,65 @@
+{
+    "$schema": "../../../tests.schema",
+    "$kind": "Microsoft.Test.Script",
+    "dialog": {
+        "$kind": "Microsoft.AdaptiveDialog",
+        "id": "ErrorLoop",
+        "autoEndDialog": true,
+        "defaultResultProperty": "dialog.result",
+        "triggers": [
+            {
+                "$kind": "Microsoft.OnBeginDialog",
+                "actions": [
+                    {
+                        "$kind": "Microsoft.SendActivity",
+                        "activity": "Throw Exception in BeginDialog."
+                    },
+                    {
+                        "$kind": "Microsoft.ThrowException",
+                        "errorValue": "Exception in BeginDialog."
+                    }
+                ]
+            },
+            {
+                "$kind": "Microsoft.OnError",
+                "actions": [
+                    {
+                        "$kind": "Microsoft.SendActivity",
+                        "activity": "Throw Exception in OnError."
+                    },
+                    {
+                        "$kind": "Microsoft.ThrowException",
+                        "errorValue": "Exception in OnError."
+                    }
+                ],
+                "executionLimit": 3
+            }
+        ]
+    },
+    "script": [
+        {
+            "$kind": "Microsoft.Test.UserSays",
+            "text": "hi"
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in BeginDialog."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Exception in OnError."
+        }
+    ]
+}

libraries/botbuilder-dialogs-adaptive-testing/tests/resources/ConditionalsTests/ConditionalsTests_OnErrorLoopDefaultLimit.test.dialog

@@ -0,0 +1,92 @@
+{
+    "$schema": "../../../tests.schema",
+    "$kind": "Microsoft.Test.Script",
+    "dialog": {
+        "$kind": "Microsoft.AdaptiveDialog",
+        "id": "ErrorLoop",
+        "autoEndDialog": true,
+        "defaultResultProperty": "dialog.result",
+        "triggers": [
+            {
+                "$kind": "Microsoft.OnBeginDialog",
+                "actions": [
+                    {
+                        "$kind": "Microsoft.SendActivity",
+                        "activity": "Throw Exception in BeginDialog."
+                    },
+                    {
+                        "$kind": "Microsoft.ThrowException",
+                        "errorValue": "Exception in BeginDialog."
+                    }
+                ]
+            },
+            {
+                "$kind": "Microsoft.OnError",
+                "actions": [
+                    {
+                        "$kind": "Microsoft.SendActivity",
+                        "activity": "Throw Exception in OnError."
+                    },
+                    {
+                        "$kind": "Microsoft.ThrowException",
+                        "errorValue": "Exception in OnError."
+                    }
+                ]
+            }
+        ]
+    },
+    "script": [
+        {
+            "$kind": "Microsoft.Test.UserSays",
+            "text": "hi"
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in BeginDialog."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Throw Exception in OnError."
+        },
+        {
+            "$kind": "Microsoft.Test.AssertReply",
+            "text": "Exception in OnError."
+        }
+    ]
+}

libraries/botbuilder-dialogs-adaptive/etc/botbuilder-dialogs-adaptive.api.md

@@ -1794,6 +1794,10 @@ export class OnError extends OnDialogEvent {
     // (undocumented)
     static $kind: string;
     constructor(actions?: Dialog[], condition?: string);
+    // (undocumented)
+    currentExecutionLimit: () => number;
+    execute(actionContext: ActionContext): Promise<ActionChangeList[]>;
+    executionLimit: NumberExpression;
     onCreateChangeList(actionContext: ActionContext, dialogOptions?: any): ActionChangeList;
 }
 

libraries/botbuilder-dialogs-adaptive/schemas/TriggerConditions/Microsoft.OnError.schema

@@ -3,5 +3,16 @@
     "$role": [ "implements(Microsoft.ITrigger)", "extends(Microsoft.OnCondition)" ],
     "title": "On error",
     "description": "Action to perform when an 'Error' dialog event occurs.",
-    "type": "object"
+    "type": "object",
+    "properties": {
+        "executionLimit": {
+            "$ref": "schema:#/definitions/numberExpression",
+            "title": "Execution limit",
+            "description": "Number of executions allowed for this trigger. Used to break loops in case of errors inside the trigger.",
+            "examples": [
+                3,
+                "=f(x)"
+            ]
+        }
+    }
 }

libraries/botbuilder-dialogs-adaptive/schemas/TriggerConditions/Microsoft.OnError.uischema

@@ -3,7 +3,8 @@
     "form": {
         "order": [
             "condition",
-            "*"
+            "*",
+            "executionLimit"
         ],
         "hidden": [
             "actions"

libraries/botbuilder-dialogs-adaptive/src/conditions/onError.ts

@@ -5,19 +5,25 @@
  * Copyright (c) Microsoft Corporation. All rights reserved.
  * Licensed under the MIT License.
  */
-import { Dialog } from 'botbuilder-dialogs';
+import { Dialog, TurnPath } from 'botbuilder-dialogs';
 import { OnDialogEvent } from './onDialogEvent';
 import { ActionContext } from '../actionContext';
 import { AdaptiveEvents } from '../adaptiveEvents';
 import { ActionChangeList } from '../actionChangeList';
 import { ActionChangeType } from '../actionChangeType';
+import { NumberExpression } from 'adaptive-expressions';
 
 /**
  * Actions triggered when an error event has been emitted.
  */
 export class OnError extends OnDialogEvent {
     static $kind = 'Microsoft.OnError';
 
+    /**
+     * Gets or sets the number of executions allowed. Used to avoid infinite loops in case of error (OPTIONAL).
+     */
+    executionLimit: NumberExpression = new NumberExpression(0);
+
     /**
      * Initializes a new instance of the [OnError](xref:botbuilder-dialogs-adaptive.OnError) class.
      *
@@ -28,6 +34,20 @@ export class OnError extends OnDialogEvent {
         super(AdaptiveEvents.error, actions, condition);
     }
 
+    /**
+     * Method called to execute the condition's actions.
+     *
+     * @param actionContext Context.
+     * @returns A promise with plan change list.
+     */
+    async execute(actionContext: ActionContext): Promise<ActionChangeList[]> {
+        const limit = this.currentExecutionLimit();
+
+        actionContext.state.setValue(TurnPath.executionLimit, limit);
+
+        return await super.execute(actionContext);
+    }
+
     /**
      * Called when a change list is created.
      *
@@ -43,4 +63,12 @@ export class OnError extends OnDialogEvent {
         changeList.changeType = ActionChangeType.replaceSequence;
         return changeList;
     }
+
+    currentExecutionLimit = function (): number {
+        if (this.executionLimit > 0) {
+            return this.executionLimit;
+        }
+        //10 is the default number of executions we'll allow before breaking the loop.
+        return 10;
+    };
 }

libraries/botbuilder-dialogs/etc/botbuilder-dialogs.api.md

@@ -823,6 +823,8 @@ export class TurnPath {
     // (undocumented)
     static readonly dialogEvent = "turn.dialogEvent";
     // (undocumented)
+    static readonly executionLimit = "turn.executionLimit";
+    // (undocumented)
     static readonly interrupted = "turn.interrupted";
     // (undocumented)
     static readonly lastResult = "turn.lastresult";

libraries/botbuilder-dialogs/src/dialogHelper.ts

@@ -94,15 +94,29 @@ export async function internalRun(
     // or we have had an exception AND there was an OnError action which captured the error. We need to continue the
     // turn based on the actions the OnError handler introduced.
     let endOfTurn = false;
+    let errorHandlerCalled = 0;
+    const TURN_STATE = 'turn';
+
     while (!endOfTurn) {
         try {
             dialogTurnResult = await innerRun(context, dialogId, dialogContext);
 
             // turn successfully completed, break the loop
             endOfTurn = true;
         } catch (err) {
+            errorHandlerCalled++;
+
             // fire error event, bubbling from the leaf.
-            const handled = await dialogContext.emitEvent(DialogEvents.error, err, true, true);
+            let handled = await dialogContext.emitEvent(DialogEvents.error, err, true, true);
+
+            let executionLimit = 0;
+            executionLimit = context.turnState.get(TURN_STATE).executionLimit;
+
+            if (executionLimit > 0 && errorHandlerCalled > executionLimit) {
+                // if the errorHandler has being called multiple times, there's an error inside the onError.
+                // We should throw the exception and break the loop.
+                handled = false;
+            }
 
             if (!handled) {
                 // error was NOT handled, throw the exception and end the turn.

libraries/botbuilder-dialogs/src/memory/turnPath.ts

@@ -45,4 +45,7 @@ export class TurnPath {
 
     /// This is a bool which if set means that the turncontext.activity has been consumed by some component in the system.
     static readonly activityProcessed = 'turn.activityProcessed';
+
+    /// Used to limit the execution of a trigger avoiding infinite loops in case of errors.
+    static readonly executionLimit = 'turn.executionLimit';
 }

libraries/tests.schema

@@ -6260,6 +6260,15 @@
         }
       },
       "properties": {
+        "executionLimit": {
+          "$ref": "#/definitions/numberExpression",
+          "title": "Execution limit",
+          "description": "Number of executions allowed for this trigger. Used to break loops in case of errors inside the trigger.",
+          "examples": [
+            3,
+            "=f(x)"
+          ]
+        },
         "condition": {
           "$ref": "#/definitions/condition",
           "title": "Condition",

libraries/tests.uischema

@@ -851,7 +851,8 @@
       "label": "Error occurred",
       "order": [
         "condition",
-        "*"
+        "*",
+        "executionLimit"
       ],
       "subtitle": "Error event"
     }