feat: add ability to skip request execution from script

vedkribhu · vedkribhu · commit abcb20c69add · 2023-10-16T10:16:59.000+05:30
diff --git a/CHANGELOG.yaml b/CHANGELOG.yaml
@@ -1,3 +1,6 @@
+master:
+    new features:
+    - GH-942 Added support for pm.execution.skipRequest
 4.2.7:
   date: 2023-08-03
   chores:
diff --git a/lib/sandbox/console.js b/lib/sandbox/console.js
@@ -45,7 +45,7 @@ function replacer (key, value) {
     return value;
 }
 
-function PostmanConsole (emitter, cursor, originalConsole) {
+function PostmanConsole (emitter, cursor, originalConsole, execution) {
     const dispatch = function (level) { // create a dispatch function that emits events
         const args = arrayProtoSlice.call(arguments, 1);
 
@@ -54,7 +54,8 @@ function PostmanConsole (emitter, cursor, originalConsole) {
             originalConsole[level].apply(originalConsole, args);
         }
 
-        emitter.dispatch(CONSOLE_EVENT, cursor, level, teleportJS.stringify(args, replacer));
+
+        emitter.dispatch(execution, CONSOLE_EVENT, cursor, level, teleportJS.stringify(args, replacer));
     };
 
     // setup variants of the logger based on log levels
diff --git a/lib/sandbox/cookie-store.js b/lib/sandbox/cookie-store.js
@@ -14,12 +14,13 @@ const _ = require('lodash'),
     arrayProtoSlice = Array.prototype.slice;
 
 class PostmanCookieStore extends Store {
-    constructor (id, emitter, timers) {
+    constructor (id, emitter, timers, execution) {
         super();
 
         this.id = id; // execution identifier
         this.emitter = emitter;
         this.timers = timers;
+        this.execution = execution;
     }
 }
 
@@ -77,7 +78,7 @@ STORE_METHODS.forEach(function (method) {
         // Refer: https://github.com/postmanlabs/postman-app-support/issues/11064
         setTimeout(() => {
             // finally, dispatch event over the bridge
-            this.emitter.dispatch(eventName, eventId, EVENT_STORE_ACTION, method, args);
+            this.emitter.dispatch(this.execution, eventName, eventId, EVENT_STORE_ACTION, method, args);
         });
     };
 });
diff --git a/lib/sandbox/execute.js b/lib/sandbox/execute.js
@@ -26,10 +26,23 @@ module.exports = function (bridge, glob) {
     // @note we use a common scope for all executions. this causes issues when scripts are run inside the sandbox
     // in parallel, but we still use this way for the legacy "persistent" behaviour needed in environment
     const scope = Scope.create({
-        eval: true,
-        ignore: ['require'],
-        block: ['bridge']
-    });
+            eval: true,
+            ignore: ['require'],
+            block: ['bridge']
+        }),
+        originalBridgeDispatch = bridge.dispatch;
+
+    bridge.dispatch = function (execution, ...args) {
+        // What is the purpose of overriding the dispatch method here?
+        // When the user invokes pm.execution.skipRequest(), our goal is to halt the current request's execution.
+        // Since we lack a foolproof method to completely halt the script's execution, our approach is to
+        // cease sending events to the bridge, creating the appearance that the script ahead never ran.
+        if (execution && execution.shouldSkipExecution) {
+            return;
+        }
+
+        return originalBridgeDispatch.call(bridge, ...args);
+    };
 
     // For caching required information provided during
     // initialization which will be used during execution
@@ -49,7 +62,7 @@ module.exports = function (bridge, glob) {
         if (!template) {
             chai.use(require('chai-postman')(sdk, _, Ajv));
 
-            return bridge.dispatch('initialize');
+            return bridge.dispatch(null, 'initialize');
         }
 
         const _module = { exports: {} },
@@ -66,7 +79,7 @@ module.exports = function (bridge, glob) {
 
         scope.exec(template, (err) => {
             if (err) {
-                return bridge.dispatch('initialize', err);
+                return bridge.dispatch(null, 'initialize', err);
             }
 
             const { chaiPlugin, initializeExecution: setupExecution } = (_module && _module.exports) || {};
@@ -79,7 +92,7 @@ module.exports = function (bridge, glob) {
                 initializeExecution = setupExecution;
             }
 
-            bridge.dispatch('initialize');
+            bridge.dispatch(null, 'initialize');
         });
     });
 
@@ -97,7 +110,8 @@ module.exports = function (bridge, glob) {
      */
     bridge.on('execute', function (id, event, context, options) {
         if (!(id && _.isString(id))) {
-            return bridge.dispatch('error', new Error('sandbox: execution identifier parameter(s) missing'));
+            return bridge.dispatch(null, 'error',
+                new Error('sandbox: execution identifier parameter(s) missing'));
         }
 
         !options && (options = {});
@@ -136,8 +150,8 @@ module.exports = function (bridge, glob) {
                 // For compatibility, dispatch the single assertion as an array.
                 !Array.isArray(assertions) && (assertions = [assertions]);
 
-                bridge.dispatch(assertionEventName, options.cursor, assertions);
-                bridge.dispatch(EXECUTION_ASSERTION_EVENT, options.cursor, assertions);
+                bridge.dispatch(execution, assertionEventName, options.cursor, assertions);
+                bridge.dispatch(execution, EXECUTION_ASSERTION_EVENT, options.cursor, assertions);
             };
 
         let waiting,
@@ -148,8 +162,8 @@ module.exports = function (bridge, glob) {
         // create the controlled timers
         timers = new PostmanTimers(null, function (err) {
             if (err) { // propagate the error out of sandbox
-                bridge.dispatch(errorEventName, options.cursor, err);
-                bridge.dispatch(EXECUTION_ERROR_EVENT, options.cursor, err);
+                bridge.dispatch(execution, errorEventName, options.cursor, err);
+                bridge.dispatch(execution, EXECUTION_ERROR_EVENT, options.cursor, err);
             }
         }, function () {
             execution.return.async = true;
@@ -169,16 +183,22 @@ module.exports = function (bridge, glob) {
             bridge.off(cookiesEventName);
 
             if (err) { // fire extra execution error event
-                bridge.dispatch(errorEventName, options.cursor, err);
-                bridge.dispatch(EXECUTION_ERROR_EVENT, options.cursor, err);
+                bridge.dispatch(null, errorEventName, options.cursor, err);
+                bridge.dispatch(null, EXECUTION_ERROR_EVENT, options.cursor, err);
             }
 
             // @note delete response from the execution object to avoid dispatching
             // the large response payload back due to performance reasons.
             execution.response && (delete execution.response);
 
             // fire the execution completion event
-            (dnd !== true) && bridge.dispatch(executionEventName, err || null, execution);
+
+            // Note: We are sending null to dispatchEvent function
+            // because this event should be fired even if shouldSkipExecution is true as this event is
+            // used to complete the execution in the sandbox. All other events are fired only if
+            // shouldSkipExecution is false.
+            (dnd !== true) && bridge.dispatch(null,
+                executionEventName, err || null, execution);
         });
 
         // if a timeout is set, we must ensure that all pending timers are cleared and an execution timeout event is
@@ -207,14 +227,19 @@ module.exports = function (bridge, glob) {
         executeContext(scope, code, execution,
             // if a console is sent, we use it. otherwise this also prevents erroneous referencing to any console
             // inside this closure.
-            (new PostmanConsole(bridge, options.cursor, options.debug && glob.console)),
+            (new PostmanConsole(bridge, options.cursor, options.debug && glob.console, execution)),
             timers,
             (
                 new PostmanAPI(execution, function (request, callback) {
                     var eventId = timers.setEvent(callback);
 
-                    bridge.dispatch(executionRequestEventName, options.cursor, id, eventId, request);
-                }, dispatchAssertions, new PostmanCookieStore(id, bridge, timers), {
+                    bridge.dispatch(execution, executionRequestEventName, options.cursor, id, eventId, request);
+                },
+                /* onSkipRequest = */ () => {
+                    execution.shouldSkipExecution = true;
+                    timers.terminate(null);
+                },
+                dispatchAssertions, new PostmanCookieStore(id, bridge, timers, execution), {
                     disabledAPIs: initializationOptions.disabledAPIs
                 })
             ),
diff --git a/lib/sandbox/execution.js b/lib/sandbox/execution.js
@@ -27,6 +27,15 @@ class Execution {
         this.id = id;
         this.target = event.listen || PROPERTY.SCRIPT;
         this.legacy = options.legacy || {};
+
+        /**
+         * This property is set to true if user has called pm.execution.skipRequest() in the script.
+         * This is used to stop the execution of the current request.
+         * We stop sending events to the bridge if this is set to true.
+         *
+         * @type {Boolean}
+         */
+        this.shouldSkipExecution = false;
         this.cursor = _.isObject(options.cursor) ? options.cursor : {};
 
         this.data = _.get(context, PROPERTY.DATA, {});
diff --git a/lib/sandbox/ping.js b/lib/sandbox/ping.js
@@ -1,7 +1,7 @@
 module.exports = {
     listener (pong) {
         return function (payload) {
-            this.dispatch(pong, payload);
+            this.dispatch(null, pong, payload);
         };
     }
 };
diff --git a/lib/sandbox/pmapi.js b/lib/sandbox/pmapi.js
@@ -44,12 +44,13 @@ const _ = require('lodash'),
  *
  * @param {Execution} execution -
  * @param {Function} onRequest -
+ * @param {Function} onSkipRequest - callback to execute when pm.execution.skipRequest() called
  * @param {Function} onAssertion -
  * @param {Object} cookieStore -
  * @param {Object} [options] -
  * @param {Array.<String>} [options.disabledAPIs] -
  */
-function Postman (execution, onRequest, onAssertion, cookieStore, options = {}) {
+function Postman (execution, onRequest, onSkipRequest, onAssertion, cookieStore, options = {}) {
     // @todo - ensure runtime passes data in a scope format
     let iterationData = new VariableScope();
 
@@ -253,6 +254,29 @@ function Postman (execution, onRequest, onAssertion, cookieStore, options = {})
         }
     }, options.disabledAPIs);
 
+    _assignDefinedReadonly(this, /** @lends Postman.prototype */ {
+        /**
+         * Exposes handlers to control execution state
+         *
+         * @interface Execution
+         */
+
+        /**
+         *
+         * @type {Execution}
+         */
+        execution: _assignDefinedReadonly({}, /** @lends Execution */ {
+            /**
+             * Stops the execution of current request. No line after this will be executed and
+             * if invoked from a pre-request script, the request will not be sent.
+             *
+             * @type {Function} skipRequest
+             * @instance
+             */
+            skipRequest: onSkipRequest
+        })
+    });
+
     // extend pm api with test runner abilities
     setupTestRunner(this, onAssertion);
 
diff --git a/test/unit/sandbox-libraries/pm.test.js b/test/unit/sandbox-libraries/pm.test.js
@@ -278,6 +278,121 @@ describe('sandbox library - pm api', function () {
             }, done);
         });
 
+        it('should not execute any line after pm.execution.skipRequest in pre-request script', function (done) {
+            context.on('console', function (level, ...args) {
+                expect(args[1]).to.equal('pre-request log 1');
+            });
+            context.execute(`
+                preRequestScript: {
+                    console.log('pre-request log 1');
+                    pm.execution.skipRequest();
+                    console.log('pre-request log 2');
+                }
+            `, {
+                timeout: 200,
+                context: {
+                    request: 'https://postman-echo.com/get?foo=bar'
+                }
+            }, function (err, execution) {
+                if (err) { return done(err); }
+                expect(execution).to.include({ shouldSkipExecution: true });
+
+                return done();
+            });
+        });
+
+        it(`should not execute any line after pm.execution.skipRequest in pre-request script,
+        even if the pm.execution.skipRequest invoked inside a try catch block`, function (done) {
+            context.on('console', function (level, ...args) {
+                expect(args[1]).to.equal('pre-request log 1');
+            });
+            context.execute(`
+                preRequestScript: {
+                    console.log('pre-request log 1');
+                    try {
+                        pm.execution.skipRequest();
+                    } catch (err) {
+                        // ignore
+                    }
+                    console.log('pre-request log 2');
+                }
+            `, {
+                timeout: 200,
+                context: {
+                    request: 'https://postman-echo.com/get?foo=bar'
+                }
+            }, function (err, execution) {
+                if (err) { return done(err); }
+                expect(execution).to.include({ shouldSkipExecution: true });
+
+                return done();
+            });
+        });
+
+        it(`should not execute any line after pm.execution.skipRequest in pre-request script,
+        even if the pm.execution.skipRequest invoked inside an async function`, function (done) {
+            context.on('console', function (level, ...args) {
+                expect(args[1]).to.equal('pre-request log 1');
+            });
+            context.execute(`
+                preRequestScript: {
+                    console.log('pre-request log 1');
+                    async function myAsyncFunction() {
+                        pm.execution.skipRequest();
+                    }
+
+                    myAsyncFunction();
+                    console.log('pre-request log 2');
+                }
+            `, {
+                timeout: 200,
+                context: {
+                    request: 'https://postman-echo.com/get?foo=bar'
+                }
+            }, function (err, execution) {
+                if (err) { return done(err); }
+                expect(execution).to.include({ shouldSkipExecution: true });
+
+                return done();
+            });
+        });
+
+        it('should not reflect any variable change line after pm.execution.skipRequest in pre-request script',
+            function (done) {
+                context.on('console', function (level, ...args) {
+                    expect(args[1]).to.equal('pre-request log 1');
+                });
+                context.execute(`
+                    preRequestScript: {
+                        async function myFun () {
+                            console.log('pre-request log 1');
+
+                            pm.variables.set('foo', 'bar');
+                            pm.execution.skipRequest();
+                            new Promise((res) => setTimeout(res, 100))
+                            pm.variables.set('foo', 'nobar');
+                            console.log('pre-request log 2');
+                        }
+
+                        myFun();
+
+                    }
+                `, {
+                    timeout: 200,
+                    context: {
+                        request: 'https://postman-echo.com/get?foo=bar'
+                    }
+                }, function (err, execution) {
+                    if (err) { return done(err); }
+                    expect(execution).to.include({ shouldSkipExecution: true });
+                    expect(execution).to.deep.nested.include({ '_variables.values': [
+                        { value: 'bar', key: 'foo', type: 'any' }
+                    ] });
+
+                    return done();
+                });
+            });
+
         it('when serialized should not have assertion helpers added by sandbox', function (done) {
             context.execute(`
                 var assert = require('assert'),
diff --git a/types/sandbox/prerequest.d.ts b/types/sandbox/prerequest.d.ts
diff --git a/types/sandbox/test.d.ts b/types/sandbox/test.d.ts

Original file line number	Diff line number	Diff line change
`@@ -45,7 +45,7 @@ function replacer (key, value) {`
`45`	`45`	`return value;`
`46`	`46`	`}`
`47`	`47`
`48`		`-function PostmanConsole (emitter, cursor, originalConsole) {`
	`48`	`+function PostmanConsole (emitter, cursor, originalConsole, execution) {`
`49`	`49`	`const dispatch = function (level) { // create a dispatch function that emits events`
`50`	`50`	`const args = arrayProtoSlice.call(arguments, 1);`
`51`	`51`
`@@ -54,7 +54,8 @@ function PostmanConsole (emitter, cursor, originalConsole) {`
`54`	`54`	`originalConsole[level].apply(originalConsole, args);`
`55`	`55`	`}`
`56`	`56`
`57`		`- emitter.dispatch(CONSOLE_EVENT, cursor, level, teleportJS.stringify(args, replacer));`
	`57`	`+`
	`58`	`+ emitter.dispatch(execution, CONSOLE_EVENT, cursor, level, teleportJS.stringify(args, replacer));`
`58`	`59`	`};`
`59`	`60`
`60`	`61`	`// setup variants of the logger based on log levels`
Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`	`1`	`module.exports = {`
`2`	`2`	`listener (pong) {`
`3`	`3`	`return function (payload) {`
`4`		`- this.dispatch(pong, payload);`
	`4`	`+ this.dispatch(null, pong, payload);`
`5`	`5`	`};`
`6`	`6`	`}`
`7`	`7`	`};`