Dockering nodejs and mongodb on EC2 ubuntu


(one host, two containers) scenario
(one ubuntu host, nodejs container + mongodb container)

//=== Official repo for nodejs on docker
https://registry.hub.docker.com/_/node/

[Dockerfile for myapp]
$ cd myapp
$ nano Dockerfile

FROM node:0.10-onbuild
EXPOSE 8080 [can be omitted?]

[build myapp image based on node:0.10?]
$ sudo docker build -t myapp .



//=== Official repo for mongodb on docker
https://registry.hub.docker.com/_/mongo/

[prerequisites]
* from https://github.com/docker-library/mongo/blob/d9fb48dbdb0b9c35d35902429fe1a28527959f25/2.2/Dockerfile
we can guess /data/db is where mongodb stores data;

* mydb.ns and mydb.0 are the data files of mongodb for myapp
copy them to local folder mymongo to build image based on Official repo mongo:2.2


[Dockerfile for mymong]
$ cd mymongo
$ nano Dockerfile

FROM mongo:2.2
Maintainer 3h
COPY mydb.ns /data/db/mydb.ns
COPY mydb.0 /data/db/mydb.0

$ sudo docker build -t mymongo .



//=== start mymongo first, then start myapp

http://blog.giantswarm.io/getting-started-with-docker-and-meanjs
[start mymongo with container named 'db']
$ sudo docker run -p 27017:27017 -d --name db mymongo


https://docs.docker.com/userguide/dockerlinks/
[start myapp with link to the running 'db' container via alias named 'mydb_alias']
$ sudo docker run -p 80:3000 --link db:mydb_alias myapp

* port 80 is for ubuntu host so that internet users can access my app;
* port 3000 is for container, which should match that used in app.js for nodejs


*** the alias name for db host, 'mydb_alias' should match that used in app.js for nodejs
ie. to establish db connection via
db host: mydb_alias
db port: 27017


//=== test mongod on docker container

[ start up mongod container ]
$ sudo docker run -p 0.0.0.0:27017:27017 -d --name db mongo:2.2
or
$ sudo docker run -p l27.0.0.1:27017:27017 -d --name db mongo:2.2
or
$ sudo docker run -p localhost:27017:27017 -d --name db mongo:2.2


[install mongo client tool]
$ sudo apt-get install mongodb-clients
$ mongo
...
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