docker-compose
When using Docker for some real world application often multiple Containers are required and to build and run them along with their Dockerfiles we need the scripts for building and running them; as realized in Dockerizing Mongo and Express. This becomes hassle and Docker has docker-compose utility that solves exactly this. We can create a “Compose file” (docker-compose.yml file) which is a YAML file; a human readable data serialization format; we configure the application services and its requirements in this file and then using the tool we can create and start all the services using this “compose file”. We define the container environment in a Dockerfile and how they relate to each other and run together in the compose file and then using the docker-compose we can build / run / stop etc them in the single go together.
Dockerfile
Docker can build images automatically by reading the instructions from a Dockerfile. Its a text file that contains the commands how to assemble the required image. This can be used as a replacement of manually creating an image from scratch installing required software etc and then exporting and loading it someplace else; the technique we discussed in the first Docker post here. We can simply handover the Dockerfile instead. Lets create a Node Container using the Dockerfile for that simple Hello World thing! Create a Dockerfile; and punch in the following
