Skip to content

Cockroach DB

Jump to bottom
Santhosh Deshineni edited this page Jun 8, 2023 · 5 revisions

Cockroach DB (SQL)

Welcome to the Cockroach DB page!

Docker Compose

  1. Install the CockroachDB Docker Image.
  2. Use this format to target a docker compose file docker-compose -f <filename> <up|build>.
  3. Run docker-compose build followed by docker-compose up in the above format on the 5 docker-compose files in 'example-app-python-django' directory to start the CockroachDB Cluster of 3 containers and two identical Django web apps in separate containers.

Note: For the first time setup, run the below four commands:

  1. docker network create -d bridge --subnet=172.16.238.0/24 roachnet with subnet set to range of ip addresses of VMs.
  2. docker volume create roach1 and similarly for roach2 and roach3 on the VM they are.
  3. docker exec -it roach1 ./cockroach init --insecure on the VM with roach1 after doing the docker compose up on roach1, 2 and 3.

Manual Docker Commands (Old Method)

The django app added above is configured to run with a local cluster of CockroachDB. The instructions to run the app in Windows are specified below:

  1. Install the CockroachDB Docker Image. Now, make sure that your working directory is set to 'example-app-python-django'.

  2. Run the below four commands in a bash terminal after ensuring that Docker Desktop is running in order to initialize a local CockroachDB cluster of 3 containers all of which are linked with each other. This cluster can be used by apps at port 26257 of localhost.
    a)docker network create -d bridge roachnet
    b)docker run -d --name=roach1 --net=roachnet -p 26257:26257 -p 8080:8080 -v "//c/Users/<username>/cockroach-data/roach1:/cockroach/cockroach-data" cockroachdb/cockroach:v22.2.2 start --insecure --join=roach1,roach2,roach3
    c)docker run -d --name=roach2 --net=roachnet -v "//c/Users/<username>/cockroach-data/roach2:/cockroach/cockroach-data" cockroachdb/cockroach:v22.2.2 start --insecure --join=roach1,roach2,roach3
    d)docker run -d --name=roach3 --net=roachnet -v "//c/Users/<username>/cockroach-data/roach3:/cockroach/cockroach-data" cockroachdb/cockroach:v22.2.2 start --insecure --join=roach1,roach2,roach3\

  3. Now, we have 3 running containers. This last command will perform the intialization of the cluster.
    docker exec -it roach1 ./cockroach init --insecure

  4. The django app can be started in the docker container using the below 2 commands.
    a)docker build . -t weba
    b)docker run --add-host host.docker.internal:host-gateway -p 8000:8080 weba
    The first command will build the image and the second command will run the container. The -add-host host.docker.internal:host-gateway allows the docker container to access the localhost ports of the host machine using the keyword host.docker.internal which has been placed in the settings.py file. This allows the app to connect to the CockroachDB cluster using the localhost port 26257. The 8000:8080 represents localhost port 8000 where we can access the app and the 8080 port is the port inside the docker container where the app is hosted.

  5. Note that the app does not have HTML pages. We can send a curl POST request using bash as shown below to add to the database and we can check if it is added using the second command which is a GET request.
    a)curl --header "Content-Type: application/json" --request POST --data '{"name":"Santhosh"}' http://127.0.0.1:8000/customer/
    b)curl http://127.0.0.1:8000/customer/

Clone this wiki locally