initial checkin

lib/middleware.js

@@ -0,0 +1,112 @@
+const debug = require('debug')('jambonz:feature-server');
+const assert = require('assert');
+const request = require('request');
+//require('request-debug')(request);
+const uuidv4 = require('uuid/v4');
+const makeTask = require('./tasks/make_task');
+
+module.exports = function(srf, logger) {
+  const {lookupAppByPhoneNumber}  = srf.locals.dbHelpers;
+
+  function initLocals(req, res, next) {
+    req.locals = req.locals || {};
+    req.locals.logger = logger.child({callId: req.get('Call-ID')});
+    next();
+  }
+
+  /**
+   * Within the system, we deal with E.164 numbers _without_ the leading '+
+   */
+  function normalizeNumbers(req, res, next) {
+    const logger = req.locals.logger;
+    Object.assign(req.locals, {
+      calledNumber: req.calledNumber,
+      callingNumber: req.callingNumber
+    });
+    try {
+      const regex = /^\+(\d+)$/;
+      let arr = regex.exec(req.calledNumber);
+      if (arr) req.locals.calledNumber = arr[1];
+      arr = regex.exec(req.callingNumber);
+      if (arr) req.locals.callingNumber = arr[1];
+    } catch (err) {
+      logger.error(err, `${req.get('Call-ID')} Error performing regex`);
+    }
+    next();
+  }
+
+  /**
+   * Given the dialed DID/phone number, retrieve the application to invoke
+   */
+  async function retrieveApplication(req, res, next) {
+    const logger = req.locals.logger;
+    try {
+      const app = req.locals.application = await lookupAppByPhoneNumber(req.locals.calledNumber);
+      if (!app) {
+        logger.info(`rejecting call to DID ${req.locals.calledNumber}: no application associated`);
+        return res.send(480, {
+          headers: {
+            'X-Reason': 'no configured application'
+          }
+        });
+      }
+      logger.debug(app, `retrieved application for ${req.locals.calledNumber}`);
+      next();
+    } catch (err) {
+      logger.error(err, `${req.get('Call-ID')} Error looking up application for ${req.calledNumber}`);
+      res.send(500);
+    }
+  }
+
+  /**
+   * Invoke the application callback and get the initial set of instructions
+   */
+  async function invokeWebCallback(req, res, next) {
+    const logger = req.locals.logger;
+    const call_sid = uuidv4();
+    const account_sid = req.locals.application.account_sid;
+    const application_sid = req.locals.application.application_sid;
+    try {
+      const app = req.locals.application;
+      assert(app && app.call_hook);
+      request.post({
+        url: app.call_hook,
+        json: true,
+        body: req.msg
+      }, (err, response, body) => {
+        if (err) {
+          logger.error(err, `Error invoking callback ${app.call_hook}`);
+          return res.send(603, 'Bad webhook');
+        }
+        logger.debug(body, 'application payload');
+        const taskData = Array.isArray(body) ? body : [body];
+        app.tasks = [];
+        for (const t in taskData) {
+          try {
+            const task = makeTask(logger, taskData[t]);
+            app.tasks.push(task);
+          } catch (err) {
+            logger.info({data: taskData[t]}, `invalid web callback payload: ${err.message}`);
+            res.send(500, 'Application Error', {
+              headers: {
+                'X-Reason': err.message
+              }
+            });
+            break;
+          }
+        }
+        if (!res.finalResponseSent) next();
+      });
+    } catch (err) {
+      logger.error(err, 'Error invoking web callback');
+      res.send(500);
+    }
+  }
+
+  return {
+    initLocals,
+    normalizeNumbers,
+    retrieveApplication,
+    invokeWebCallback
+  };
+};