MyLittleMicroservice
This Project represents a networked/connected Microservice written in NodeJS and MongoDB by using docker-compose.
The first container (NodeServer) includes the NodeJS Server which calls an single entry from the dockerized MongoDB database called "MongolianData". Its collection name is "myNewCollection" and includes the single Entry [{_id:2}] which is about a book, as an example. The aim here is not just to retrieve that single entry. Moreover it was about networking the NodeJS and MongoDB images inside a shared container through using "Docker Networking" and "Docker-compose.yml".
This combination represent 1 Microservice which can be used to create multiple duplicated containers or adding some great features/images containing LoadBalanicng, CircuitBreakers or even better: Kubernetes, NGINX and so on.
At the end, an alias for the database was used to access the database. That alias("mongoservice") was set inside the "Docker-compose.yml" file.
MongoClient.connect("mongodb://mongoservice:27017/",{useNewUrlParser: true,useUnifiedTopology:true},function(err, client) {
if (err) throw err;
var query = {"_id": 2};
var db = client.db('MongolianData');
db.collection("myNewCollection").find(query).toArray(function(err, result) {
if (err) throw err;
console.log(result);
client.close();
});
});My biggest problem
was that i FORGET to do first:
docker-compose buildand after that :
docker-compose upCode changes on your local PC/IDE will surely applied and saved on your pc. But if you donÄt write "docker-compose build", the changes will NOT be applied inside your shared container!!! Always "build" first and then type "up". That issue has been led me to many bugs.