2.14.0 rewrite: modularization

1 files changed, 73 insertions, 0 deletions

diff --git a/service_skeleton.js b/service_skeleton.js
new file mode 100644
index 0000000..1dc9a3b
--- /dev/null
+++ b/service_skeleton.js
@@ -0,0 +1,73 @@
+#!/usr/bin/env node
+/* jshint esnext: true */
+"use strict";
+
+const Promise = require("bluebird");
+
+const logger = global.logger,
+    KEY_TYPE = process.env.KEY_TYPE || "crunch";  // backwards compat
+
+module.exports = class Service {
+    setRoutes(routes) {  // route str -> func
+        this.routes = new Map(Object.entries(routes));
+    }
+
+    setDatabases(dbs, defaultDb) {  // mode str -> Sequelize
+        this.dbs = new Map(Object.entries(dbs));
+    }
+    getDatabase(category) {
+        if (!this.dbs.has(category))
+            logger.error("unsupported database category");
+        return this.dbs.get(category);
+    }
+
+    async register(rmqChannel, expressApp) {  // assert queues, initialize routes
+        this.notify = async (topic, msg) =>
+            await rmqChannel.publish("amq.topic", topic, new Buffer(msg));
+        this.forward = async (queue, payload, options) =>
+            await rmqChannel.sendToQueue(queue, new Buffer(payload), options);
+
+        await Promise.all(this.targets, (queue) =>
+            rmqChannel.assertQueue(queue, { durable: true }));
+
+        for(let [route, func] of this.routes) {
+            expressApp.post(route, func);
+        }
+    }
+
+    setTargets(queues) {  // set channels messages can be forwarded to, str -> str
+        this.targets = new Map(Object.entries(queues));
+    }
+    getTarget(category) {  // return channel for category
+        if (!this.targets.has(category))
+            logger.error("unsupported queue category", category);
+        return this.targets.get(category);
+    }
+
+    // return an entry from keys db
+    async getKey(category, key, default_value) {
+        const db = this.getDatabase(category),
+            record = await db.Keys.findOrCreate({
+                where: {
+                    type: KEY_TYPE,
+                    key: key
+                },
+                defaults: { value: default_value }
+            });
+        return record[0].value;
+    }
+
+    // update an entry from keys db
+    async setKey(category, key, value) {
+        const db = this.getDatabase(category),
+            record = await db.Keys.findOrCreate({
+                where: {
+                    type: KEY_TYPE,
+                    key: key
+                },
+                defaults: { value: value }
+            });
+        record[0].update({ value: value });
+        return value;
+    }
+}