Feature/siprec server (#140)

* initial support for siprec/agent assist

* call siprec middleware

* logger fix

* remove verbs that are not valid in a siprec call session

lib/middleware.js

@@ -1,5 +1,6 @@
 const { v4: uuidv4 } = require('uuid');
-const {CallDirection} = require('./utils/constants');
+const {CallDirection, TaskName} = require('./utils/constants');
+const {parseSiprecPayload} = require('./utils/siprec-utils');
 const CallInfo = require('./session/call-info');
 const HttpRequestor = require('./utils/http-requestor');
 const WsRequestor = require('./utils/ws-requestor');
@@ -73,6 +74,35 @@ module.exports = function(srf, logger) {
     next();
   }
 
+  const handleSipRec = async(req, res, next) => {
+    if (Array.isArray(req.payload) && req.payload.length > 1) {
+      const {callId, logger} = req.locals;
+      logger.debug({payload: req.payload}, 'handling siprec call');
+
+      try {
+        const sdp = req.payload
+          .find((p) => p.type === 'application/sdp')
+          .content;
+        const {sdp1, sdp2, ...metadata} = await parseSiprecPayload(req, logger);
+        req.locals.calledNumber = metadata.caller.number;
+        req.locals.callingNumber = metadata.callee.number;
+        req.locals = {
+          ...req.locals,
+          siprec: {
+            metadata,
+            sdp1,
+            sdp2
+          }
+        };
+        logger.info({callId, metadata, sdp}, 'successfully parsed SIPREC payload');
+      } catch (err) {
+        logger.info({callId}, 'Error parsing multipart payload');
+        return res.send(503);
+      }
+    }
+    next();
+  };
+
   /**
    * retrieve account information for the incoming call
    */
@@ -101,7 +131,10 @@ module.exports = function(srf, logger) {
    * Within the system, we deal with E.164 numbers _without_ the leading '+
    */
   function normalizeNumbers(req, res, next) {
-    const logger = req.locals.logger;
+    const {logger, siprec} = req.locals;
+
+    if (siprec) return next();
+
     Object.assign(req.locals, {
       calledNumber: req.calledNumber,
       callingNumber: req.callingNumber
@@ -225,7 +258,7 @@ module.exports = function(srf, logger) {
    */
   async function invokeWebCallback(req, res, next) {
     const logger = req.locals.logger;
-    const {rootSpan, application:app} = req.locals;
+    const {rootSpan, siprec, application:app} = req.locals;
     let span;
     try {
       if (app.tasks) {
@@ -261,6 +294,19 @@ module.exports = function(srf, logger) {
       });
       span.end();
       if (0 === app.tasks.length) throw new Error('no application provided');
+
+      if (siprec) {
+        /* only transcribe and/or listen allowed on an incoming siprec call */
+        const tasks = app.tasks.filter((t) => [TaskName.Config, TaskName.Listen, TaskName.Transcribe].includes(t.name));
+        if (0 === tasks.length) {
+          logger.info({tasks: app.tasks}, 'only config, transcribe and/or listen allowed on an incoming siprec call');
+          throw new Error('invalid verbs for incoming siprec call');
+        }
+        if (tasks.length < app.tasks.length) {
+          logger.info('removing verbs that are not allowed for incoming siprec call');
+          app.tasks = tasks;
+        }
+      }
       next();
     } catch (err) {
       span?.setAttributes({webhookStatus: err.statusCode});
@@ -274,6 +320,7 @@ module.exports = function(srf, logger) {
   return {
     initLocals,
     createRootSpan,
+    handleSipRec,
     getAccountDetails,
     normalizeNumbers,
     retrieveApplication,