agent/agent-ngrok.js

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

/* eslint-disable strict */

// agent that forwards invocations to the developer's computer using ngrok.com

const openwhisk = require('openwhisk');
const https = require('https');

// Note: this function is duplicated by all agents
function hit(args, condition) {
    if (condition) {
        console.log("arguments:", args);
        console.log("evaluating hit condition: ", condition);
        // eslint-disable-next-line no-with
        with (args) { // lgtm [js/with-statement]
            try {
                // eslint-disable-next-line no-eval
                return eval(condition);
            } catch (e) {
                console.log("failed to eval condition:", e);
                // be safe: do not hit if error in condition
                return false;
            }
        }
    } else {
        // no condition => always hit
        return true;
    }
}

async function doMain(args) {
    // normal activation: make activation available to debugger
    console.log("activation");

    if (hit(args, args.$condition) && args.$ngrokUrl) {
        console.log("passing on to debugger");

        console.log("post to ngrok", args.$ngrokUrl);
        const options = {
            hostname: args.$ngrokUrl,
            port: 443,
            path: '/',
            method: 'POST',
            headers: {
                authorization: args.$ngrokAuth
            }
        };
        return new Promise((resolve, reject) => {
            const req = https.request(options, (resp) => {
                console.log("response: ", resp.statusCode);
                let body = '';

                // A chunk of data has been recieved.
                resp.on('data', (chunk) => {
                    body += chunk;
                });

                // The whole response has been received. Print out the result.
                resp.on('end', () => {
                    resolve(JSON.parse(body));
                });

            });
            req.on("error", err => {
                console.error(err);
                reject(err);
            });
            args.$activationId = process.env.__OW_ACTIVATION_ID;
            delete args.$ngrokUrl;
            delete args.$ngrokAuth;
            req.write(JSON.stringify(args));
            req.end();
        });

    } else {
        console.log("condition evaluated to false (or $ngrokUrl missing), executing original action");
        return openwhisk().actions.invoke({
            name: `${process.env.__OW_ACTION_NAME}_wskdebug_original`,
            params: args,
            blocking: true,
            result: true
        });
    }
}

// OpenWhisk does not like raw exceptions, the error object should be the string message only
// eslint-disable-next-line no-unused-vars
async function main(args) {
    try {
        return await doMain(args);
    } catch (e) {
        console.log("Exception:", e);
        return Promise.reject({ error: e.message, code: e.code});
    }
}