feat: use feature flags

config/index.js

@@ -37,7 +37,11 @@ const config = {
             'bugsnag_key',
             'cookie'
         ],
-        bugsnag_key: process.env.BUGSNAG_KEY_CORE || 'CHANGEME'
+        bugsnag_key: process.env.BUGSNAG_KEY || 'CHANGEME',
+        featureflag_url: process.env.FEATUREFLAG_URL || 'CHANGEME',
+        featureflag_token: process.env.FEATUREFLAG_TOKEN || 'CHANGEME',
+        flagsmith_token: process.env.FLAGSMITH_TOKEN || 'CHANGEME',
+        devcycle_token: process.env.DEVCYCLE_TOKEN || 'CHANGEME',
     },
     development: {
 

docker/docker-compose.yml

@@ -30,6 +30,14 @@ services:
             HOST: "${SUBDOMAIN_FRONTEND}${BASE_URL}"
             CORE_LOGIN: "${CORE_LOGIN}"
             CORE_PASSWORD: "${CORE_PASSWORD}"
+            LOGLEVEL: "warn"
+            # it's gonna be one of those three offerings in the end
+            # NB: all are selfhosted except there's no trace of devcycle docker.
+            # maybe they removed the offering
+            FEATUREFLAG_URL: "${FEATUREFLAG_URL}"
+            FEATUREFLAG_TOKEN: "${FEATUREFLAG_TOKEN}"
+            FLAGSMITH_TOKEN: "${FLAGSMITH_TOKEN}"
+            DEVCYCLE_TOKEN: "${DEVCYCLE_TOKEN}"
         healthcheck:
             test: ["CMD", "curl", "-f", "http://localhost:8084/healthcheck"]
             interval: 30s

lib/featureflags.js

@@ -0,0 +1,81 @@
+const Flagsmith = require('flagsmith-nodejs'); // nice but less strategies, weirder to selfhost
+const { Unleash } = require('unleash-client'); // cumbersome with the proxy thing but seems ok, good to selfhost
+const DVC = require('@devcycle/nodejs-server-sdk'); // what the actual fuck to get the flag
+const config = require('../config');
+const logger = require('./logger');
+
+// NOTE: for all three providers, the choice of environment is
+// via the API key (i.e. there's an API key for each env)
+
+/** Flagsmith */
+
+let flagsmith;
+if (!flagsmith) {
+    flagsmith = new Flagsmith({
+        environmentKey: config.flagsmith_token,
+    });
+    logger.info('Feature Flag: provider flagsmith initialised');
+}
+
+/* usage:
+var showButton = flags.isFeatureEnabled('secret_button');
+var buttonData = flags.getFeatureValue('secret_button');
+*/
+
+/** unleash */
+
+let unleash;
+if (!unleash) {
+    unleash = new Unleash({
+        url: config.featureflag_url, // NOT proxy but the :4242/api
+        appName: 'Default', // can't change the stupid name in the unleash UI...
+        customHeaders: { Authorization: config.featureflag_token },
+    });
+    logger.info('Feature Flag: provider unleash initialised');
+}
+
+/** DevCycle */
+
+let devcycleClient;
+
+async function initializeDevCycle() {
+    try {
+        devcycleClient = await DVC.initializeDevCycle(config.devcycle_token).onClientInitialized();
+        logger.info('Feature Flag: provider DVC initialised');
+    } catch (ex) {
+        return logger.error(`Error initializing DevCycle: ${ex}`);
+    }
+}
+
+if (!devcycleClient) initializeDevCycle();
+
+function returnDVCVariable(feature, user = null) {
+    // The user data must be passed into every method, only the user_id is required
+    const userDescription = user || {
+        user_id: 'user1@devcycle.com', // whatever name or ID works
+        name: 'user 1 name',
+        customData: {
+            customKey: 'customValue'
+        }
+    };
+
+    // Fetch variable values using the identifier key coupled with a default value
+    // The default value can be of type string, boolean, number, or object
+    const dvcVariableValue = devcycleClient.variableValue(userDescription, feature, false);
+    return dvcVariableValue;
+}
+
+async function isFFEnabled(feature, engine = 'flagsmith') {
+    switch (engine) {
+    case 'dvc':
+        return returnDVCVariable(feature);
+    case 'unleash':
+        return unleash.isEnabled(feature);
+    default:
+        // eslint-disable-next-line no-case-declarations
+        const flags = await flagsmith.getEnvironmentFlags();
+        return flags.isFeatureEnabled(feature);
+    }
+}
+
+module.exports = isFFEnabled;

lib/mailer.js

@@ -1,27 +1,30 @@
 const request = require('request-promise-native');
-
+const amqp = require('amqplib/callback_api');
+const logger = require('./logger');
+const isFFEnabled = require('./featureflags');
 const config = require('../config');
 
 /**
  * @param {Object} options
  * @param {string|string[]} options.to
- * @param {string} options.template
- * @param {string} options.subject
  * @param {object} options.reply_to
+ * @param {string} options.subject
+ * @param {string} options.template
  * @param {object} options.parameters
  */
-module.exports.sendMail = async (options) => {
+const sendMail = async (options) => {
+    logger.error('into old mailer');
     const mailerBody = await request({
         url: config.mailer.url + ':' + config.mailer.port + '/',
         method: 'POST',
         simple: false,
         json: true,
         body: {
             to: options.to,
+            reply_to: options.reply_to,
             subject: options.subject,
             template: options.template,
-            parameters: options.parameters,
-            reply_to: options.reply_to
+            parameters: options.parameters
         }
     });
 
@@ -35,3 +38,53 @@ module.exports.sendMail = async (options) => {
 
     return mailerBody;
 };
+
+const queue = 'email';
+const enqueuer = async (options) => {
+    amqp.connect('amqp://rabbit', (error0, connection) => {
+        if (error0) {
+            throw error0;
+        }
+        connection.createChannel((error1, channel) => {
+            if (error1) {
+                throw error1;
+            }
+
+            const msg = {
+                from: 'mailer@aegee.eu', // it was auto-set in mailer, here we must set it
+                to: options.to,
+                reply_to: options.reply_to || 'noreply@aegee.eu', // FIXME
+                subject: options.subject,
+                template: options.template,
+                parameters: options.parameters,
+            };
+
+            // channel.assertQueue(queue, {
+            //     durable: true,
+            //     'x-dead-letter-exchange': 'dead_letter_exchange'
+            // });
+
+            channel.sendToQueue(queue, Buffer.from(JSON.stringify(msg)));
+            logger.info(' [x] Sent %s', msg);
+        });
+        setTimeout(() => {
+            connection.close();
+        }, 500);
+        return { response: { success: true } }; // TODO: handle rabbit issues
+    });
+};
+
+// This function is in order to bypass the fact that one can't
+// change the export at runtime
+const sender = async (options) => {
+    if (await isFFEnabled('new_mailer')) {
+        logger.info('Experimental: new mailer');
+        options.template = options.template.replace('.html', ''); // the dispatcher adds the extension
+        const thevalue = await enqueuer(options);
+        return thevalue;
+    }
+    const thevalue = await sendMail(options);
+    return thevalue;
+};
+
+module.exports.sendMail = sender;