Add elasticsearch service, environment and loader

Some observations: There are two elasticsearch packages in npm worth
looking at, 'elasticsearch' and '@elastic/elasticsearch'. The second
is meant to replace the first, but mongoose-elasticsearch-xp which will
handle the replication of models apparently uses clients from the first.
Further down the line we can test if '@elastic/elasticsearch' and be
used instead.

The elasticsearch client is uncaptured.

Use makeConfig() to prevent future issues:
See elastic/elasticsearch-js#33

.env

@@ -11,6 +11,17 @@ DB_PASS=
 # Specifies the name of the database to connect to
 DB_NAME=nijobs
 
+# Specifies the host for the elasticsearch instance
+ES_HOST=localhost
+# Specifies the port for the elasticsearch instance
+ES_PORT=9200
+# For use with external instances if 'http://$HOST:$PORT' is insufficient
+ES_URI=
+# Specifies the username with which to connect to the instance
+ES_USER=
+# Specified the password with which to connect to the instance
+ES_PASS=
+
 # Session secret - OVERRIDE IN PRODUCTION
 SESSION_SECRET=O Rui foi membro do IEEE.
 

docker-compose.yml

@@ -1,7 +1,7 @@
 version: "3"
 services:
   web-prod:
-    build: 
+    build:
       context: .
       dockerfile: Dockerfile-prod
     environment:
@@ -10,6 +10,7 @@ services:
       - "${PORT}:${PORT}"
     depends_on:
       - mongo
+      - elasticsearch
   web-dev:
     build:
       context: .
@@ -22,6 +23,7 @@ services:
       - ./src:/usr/src/nijobs-be/src
     depends_on:
       - mongo
+      - elasticsearch
   test:
     build:
       context: .
@@ -37,3 +39,9 @@ services:
     image: mongo
     ports:
       - "27017:27017"
+  elasticsearch:
+    image: elasticsearch:7.6.1
+    environment:
+      - discovery.type=single-node
+    ports:
+      - "9200:9200"

package.json

@@ -27,11 +27,13 @@
     "bcrypt": "^3.0.6",
     "body-parser": "^1.18.3",
     "dotenv-flow": "^3.0.0",
+    "elasticsearch": "^16.6.0",
     "express": "^4.16.4",
     "express-session": "^1.15.6",
     "express-validator": "^6.2.0",
     "http-status-codes": "^1.4.0",
     "mongoose": "^5.7.5",
+    "mongoose-elasticsearch-xp": "^5.8.0",
     "mongoose-unique-array": "^0.3.1",
     "morgan": "^1.9.1",
     "passport": "^0.4.0",

src/config/env.js

@@ -9,6 +9,12 @@ module.exports = Object.freeze({
     db_pass: process.env.DB_PASS,
     db_name: process.env.DB_NAME,
 
+    es_host: process.env.ES_HOST,
+    es_port: process.env.ES_PORT,
+    es_uri: process.env.ES_URI,
+    es_user: process.env.ES_USER,
+    es_pass: process.env.ES_PASS,
+
     session_secret: process.env.SESSION_SECRET,
 
     port: process.env.PORT,

src/loaders/elasticsearch.js

@@ -0,0 +1,26 @@
+const elasticsearch = require("elasticsearch");
+const config = require("../config/env");
+
+const makeConfig = () => {
+    if (!(config.db_uri || (config.db_host && config.db_port))) {
+        console.error("Either 'ES_URI' or 'ES_HOST' and 'ES_PORT' must be specified in the env file! See README.md for details.");
+        process.exit(125);
+    }
+
+    const pass = config.es_pass ? `:${config.es_pass}` : "";
+    const auth = `${config.es_user}${pass}`;
+
+    const uri = config.es_uri || `http://${config.es_host}:${config.es_port}`;
+
+    return {
+        host: uri,
+        httpAuth: auth,
+        log: "trace", // development only
+        apiVersion: "7.6",
+        name: "nijobs-es",
+    };
+};
+
+const setupClient = () => elasticsearch.Client(makeConfig());
+
+module.exports = setupClient;

src/loaders/index.js

@@ -1,9 +1,12 @@
 const mongooseLoader = require("./mongoose");
+const elasticsearchLoader = require("./elasticsearch");
 const expressLoader = require("./express");
 
 const setupLoaders = async ({ expressApp }) => {
     await mongooseLoader();
     console.info("Mongoose DB connection initialized");
+    await elasticsearchLoader();
+    console.info("Elasticsearch connection initialized");
     await expressLoader(expressApp);
     console.info("Express initialized");
     require("../config/passport");