flow: default service, gateway, emitters

.common.env

@@ -1,3 +1,5 @@
 npm_config_registry=https://npm.i12e.cha0s.io
 
 NODE_PATH=/var/node/dist/node_modules
+
+GATEWAY_EMITTERS=@truss/emitters/http

services/default/.gitignore

@@ -0,0 +1 @@
+node_modules

services/default/actions.js

@@ -0,0 +1,2 @@
+module.exports = (serviceMap) => ({
+});

services/default/compose.js

@@ -0,0 +1,3 @@
+module.exports = (config) => {
+};
+

services/default/hooks.js

@@ -0,0 +1,2 @@
+module.exports = () => ({
+});

services/default/index.js

@@ -0,0 +1,15 @@
+const {createDispatcher} = require('@truss/comm');
+
+const dispatcher = createDispatcher();
+dispatcher.lookupActions(require('./actions'));
+dispatcher.lookupHooks(require('./hooks'));
+dispatcher.connect();
+
+if (module.hot) {
+  module.hot.accept('./actions', () => {
+    dispatcher.lookupActions(require('./actions'));
+  });
+  module.hot.accept('./hooks', () => {
+    dispatcher.lookupHooks(require('./hooks'));
+  });
+}

services/default/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "default",
+  "version": "1.0.0",
+  "description": "Default service. Clone or customize!",
+  "main": "index.js",
+  "private": true,
+  "scripts": {
+    "build": "node -e '' -r '@truss/webpack/task/build'",
+    "default": "yarn run dev",
+    "dev": "node -e '' -r '@truss/webpack/task/scaffold'"
+  },
+  "license": "MIT",
+  "dependencies": {
+    "@truss/comm": "1.x",
+    "@truss/webpack": "1.x"
+  }
+}

services/gateway/actions.js

@@ -2,18 +2,18 @@ const {sendActionToService} = require('@truss/comm');
 
 const debug = require('debug')('truss:gateway:actions');
 
-module.exports = (serviceMap) => ({
-  'truss/hook-services': ({payload: {hook, args}}) => {
-    if (!(hook in serviceMap.hooks)) { return []; }
-    return serviceMap.hooks[hook];
+module.exports = (hooks) => ({
+  '@truss/hook-services': ({payload: {hook, args}}) => {
+    if (!(hook in hooks)) { return []; }
+    return hooks[hook];
   },
-  'truss/invoke': ({payload: {hook, args}}) => {
-    if (!(hook in serviceMap.hooks)) { return {}; }
-    return invokeHook(serviceMap.hooks[hook], hook, args);
+  '@truss/invoke': ({payload: {hook, args}}) => {
+    if (!(hook in hooks)) { return {}; }
+    return invokeHook(hooks[hook], hook, args);
   },
-  'truss/invoke-flat': ({payload: {hook, args}}) => {
-    if (!(hook in serviceMap.hooks)) { return []; }
-    return invokeHookFlat(serviceMap.hooks[hook], hook, args);
+  '@truss/invoke-flat': ({payload: {hook, args}}) => {
+    if (!(hook in hooks)) { return []; }
+    return invokeHookFlat(hooks[hook], hook, args);
   },
 });
 
@@ -23,7 +23,7 @@ function invokeHookFlat(services, hook, args) {
 }
 
 function invokeHookFlatInternal(services, hook, args) {
-  const action = {type: 'truss/hook', payload: {hook, args}};
+  const action = {type: '@truss/hook', payload: {hook, args}};
   return Promise.all(services.map((service) => {
     return sendActionToService(action, service);
   }));

services/gateway/compose.js

@@ -2,4 +2,3 @@ module.exports = (config) => {
   const gatewayPort = process.env.GATEWAY_PORT || 8000;
   config.ports = [`${gatewayPort}:8000`];
 };
-

services/gateway/index.js

@@ -1,82 +1,40 @@
+// Core.
 const http = require('http');
-
+// 3rd party.
 const debug = require('debug')('truss:gateway');
-
-const {createDispatcher, sendActionToService} = require('@truss/comm');
-
-let listener = require('./listener').default;
-
-// ---
-
-if (!process.env.SERVICES) {
-  console.error('$SERVICES must be defined!');
-  process.exit(1);
-}
-const services = process.env.SERVICES.split(',');
-
-// get all schemas
-const schemas$ = services.map((service) => {
-  return sendActionToService({type: 'truss/schema'}, service);
-});
-
-// build service map
-const reduceServiceMap$ = Promise.all(schemas$).then((schemas) => {
-  return schemas.reduce((serviceMap, schema, i) => {
-    const service = services[i];
-    for (const type of (schema.executors || [])) {
-      if (serviceMap.executors[type]) {
-        throw new RangeError(`
-          Only one executor may be specified per action type! "${service}"
-          tried to register an executor but "${serviceMap.executors[type]}"
-          already registered one for "${type}".
-        `.replace(/\s+/g, ' ').trim());
+// 2nd party.
+const {createDispatcher} = require('@truss/comm');
+// 1st party.
+const {loadServiceMap} = require('./service-map');
+// Main.
+(async () => {
+  try {
+    debug(`loading service map...`);
+    const serviceMap = await loadServiceMap();
+    const {executors, hooks, listeners} = serviceMap;
+    debug(`service map: ${JSON.stringify(serviceMap, null, '  ')}`);
+    const dispatcher = createDispatcher();
+    dispatcher.setArgs(hooks);
+    dispatcher.lookupActions(require('./actions'));
+    if (module.hot) {
+      module.hot.accept('./actions', () => {
+        dispatcher.lookupActions(require('./actions'));
+      });
+    }
+    const emitterPaths = process.env.GATEWAY_EMITTERS.split(':');
+    const emitters = [];
+    for (const emitterPath of emitterPaths) {
+      const Class = __non_webpack_require__(emitterPath);
+      emitters.push(new Class(executors, listeners));
+    }
+    const server = dispatcher.connect();
+    server.on('listening', () => {
+      for (const emitter of emitters) {
+        emitter.listen();
       }
-      serviceMap.executors[type] = service;
-    }
-    for (const type of (schema.listeners || [])) {
-      serviceMap.listeners[type] = serviceMap.listeners[type] || [];
-      serviceMap.listeners[type].push(service);
-    }
-    for (const hook of (schema.hooks || [])) {
-      serviceMap.hooks[hook] = serviceMap.hooks[hook] || [];
-      serviceMap.hooks[hook].push(service);
-    }
-    return serviceMap;
-  }, {
-    executors: {},
-    hooks: {},
-    listeners: {},
-  });
-});
-
-// hey, listen
-const httpServer = http.createServer();
-reduceServiceMap$.then((serviceMap) => {
-  debug(`service map: ${JSON.stringify(serviceMap, null, '  ')}`);
-
-  const dispatcher = createDispatcher();
-  dispatcher.setArgs(serviceMap);
-  dispatcher.lookupActions(require('./actions'));
-  if (module.hot) {
-    module.hot.accept('./actions', () => {
-      dispatcher.lookupActions(require('./actions'));
     });
   }
-  const server = dispatcher.connect();
-  server.on('listening', () => {
-    const port = process.env.GATEWAY_PORT || 8000;
-    httpServer.listen(port);
-    httpServer.on('listening', () => {
-      debug(`HTTP listening on port ${port}...`);
-    })
-    httpServer.on('request', (req, res) => {
-      listener(serviceMap, req, res);
-    });
-  });
-}).catch(console.error);
-
-if (module.hot) {
-  module.hot.accept('./listener', () => {
-    listener = require('./listener').default;
-  });
-}
+  catch (error) {
+    console.error(error);
+  }
+})();

services/gateway/listener.js

@@ -7,25 +7,32 @@ const debug = require('debug')('truss:gateway:listener');
 const parser = bodyParser.json();
 
 export default function(serviceMap, req, res) { parser(req, res, () => {
-  debug(`HTTP ${req.method} ${req.url}`);
+  const method = req.method.toLowerCase();
+  debug(`HTTP ${method} ${req.url}`);
   // map to action
-  const action = {type: undefined, payload: {url: req.url}};
-  switch (req.method) {
-    case 'POST':
+  const action = {
+    type: undefined,
+    payload: {
+      headers: req.headers,
+      method: method,
+      url: req.url,
+    }
+  };
+  switch (method) {
+    case 'post':
       // truss action
       if (req.url.startsWith('/truss/action/')) {
         action.type = req.url.substr('/truss/action/'.length);
       }
-      // truss/http-post
+      // @truss/http-post
       else {
-        action.type = 'truss/http-post';
+        action.type = '@truss/http-post';
       }
       action.payload.body = req.body;
       break;
     default:
-      // truss/http-(get|delete|...)
-      action.type = `truss/http-${req.method.toLowerCase()}`;
-      action.payload.headers = req.headers;
+      // @truss/http-(get|delete|...)
+      action.type = `@truss/http-${method}`;
       break;
   }
   // listeners...

services/gateway/package.json

@@ -12,6 +12,7 @@
   "license": "MIT",
   "dependencies": {
     "@truss/comm": "1.x",
+    "@truss/emitters": "1.x",
     "@truss/webpack": "1.x",
     "body-parser": "1.18.3",
     "debug": "3.1.0"

services/gateway/service-map.js

@@ -0,0 +1,43 @@
+const {sendActionToService} = require('@truss/comm');
+
+if (!process.env.SERVICES) {
+  console.error('$SERVICES must be defined!');
+  process.exit(1);
+}
+const services = process.env.SERVICES.split(',');
+
+export function loadServiceMap() {
+  // get all schemas
+  const schemas$ = services.map((service) => {
+    return sendActionToService({type: '@truss/schema'}, service);
+  });
+  // build service map
+  return Promise.all(schemas$).then((schemas) => {
+    return schemas.reduce((serviceMap, schema, i) => {
+      const service = services[i];
+      for (const type of (schema.executors || [])) {
+        if (serviceMap.executors[type]) {
+          throw new RangeError(`
+            Only one executor may be specified per action type! "${service}"
+            tried to register an executor but "${serviceMap.executors[type]}"
+            already registered one for "${type}".
+          `.replace(/\s+/g, ' ').trim());
+        }
+        serviceMap.executors[type] = service;
+      }
+      for (const type of (schema.listeners || [])) {
+        serviceMap.listeners[type] = serviceMap.listeners[type] || [];
+        serviceMap.listeners[type].push(service);
+      }
+      for (const hook of (schema.hooks || [])) {
+        serviceMap.hooks[hook] = serviceMap.hooks[hook] || [];
+        serviceMap.hooks[hook].push(service);
+      }
+      return serviceMap;
+    }, {
+      executors: {},
+      hooks: {},
+      listeners: {},
+    });
+  });
+}