Flexible Search with Express Framework

Question

I want to create an application and api that will basically fetch the resource. Now I have heard a lot about Nodejsand ElasticSearch, and I know a little Nodejs and Express framework. But I do not know how to integrate ElasticSearch with Express.

Answer 1

• 1 download ElasticSearch
• Inside your project / Express directory framework download ElasticSearch express driver using npm install elasticsearch --save
• Run an instance of ElasticSearch, by default it runs on port 9200

• To use this module, just create a client instance

  var elasticsearch = require('elasticsearch');
  var client = elasticsearch.Client({
    host: 'localhost:9200'
  });
  
  client.search({
    index: 'books',
    type: 'book',
    body: {
      query: {
        multi_match: {
          query: 'express js',
          fields: ['title', 'description']
        }
      }
    }
  }).then(function(response) {
    var hits = response.hits.hits;
  }, function(error) {
    console.trace(error.message);
  });
  

• Helpfull Link https://blog.raananweber.com/2015/11/24/simple-autocomplete-with-elasticsearch-and-node-js/

Answer 2

-, , Elasticsearch.

Node.js: https://github.com/elastic/elasticsearch-js

,

var elasticsearch = require('elasticsearch');
var client = new elasticsearch.Client({
  host: '<your_instance_ip>:9200',
  log: 'trace'
});

client.send client.search .

Answer 3

OSx

1. elasticsearch

• brew elasticsearch//

• elasticsearch//

2.

2.1 ES

• npm install elasticsearch --save

2.2

• FOLDER : routers/elastic-search-router.js

  var express= require('express');
  var router= express.Router();
  var elasticsearch=require('elasticsearch');
  var client = new elasticsearch.Client( {  
               hosts: [
                       'http://localhost:9200/',//DEFAULT URL
                      //'https://[username]:[password]@[server]:[port]/'
                      ]
   });
  
   /* This operation health of es */
   router.get('/health',function(req,res){
     client.cluster.health({},function(err,resp,status) {  
        if(err)
        {  console.log("-- Client Health ERROR--",err);
        }else{
           console.log("-- Client Health --",resp);
           res.send({resp});
        }
     });
   });
   /* This operation For Creating new Index of es */
   router.get('/createIndex',function(req,res){
     client.indices.create({  
          index: 'imageMap'
     },function(err,resp,status) {
     if(err) {
       console.log(err);
     }
     else {
        console.log("create",resp);
        res.send({resp});
     }
   });
  });
  module.exports =router;
  

2.2 Now inside the Express index.js file

    // Setup an Express app
    var express = require('express');
    var app = express();
    var bodyParser = require('body-parser');
    var path= require('path');
    //use routers
    app.use(require(path.join(__dirname,'routers/elastic-search-router')));
    ....

2.3 Launch Express Server:

IN TERMINAL : node index.js

3. In the application url, you can access each function in ur router as:

   http: // localhost: 3000 / createIndex

   http: // localhost: 3000 / health