Codeship demo case: write CI environment variables to file in image

codeship-services.yml

# codeship-services.yml
revision:
  build:
    image: rev
    dockerfile_path: ./Dockerfile-revision
  volumes:
    - ./data:/data
app:
  build:
    image: app
    dockerfile_path: ./Dockerfile-app

codeship-steps.yml

# codeship-steps.yml
- name: Set build version in local file data/BUILD_REV
  service: revision
  command: write_build_rev

- name: Build app
  service: app
  command: /bin/true

Dockerfile-app

FROM busybox

COPY data/BUILD_REV /

Dockerfile-revision

FROM busybox

RUN mkdir /data
COPY write_build_rev bin/

output.txt

⚡ jet steps
{StepStarted=step_name:"Set build version in local file data/BUILD_REV"}
{BuildImageStarted=image_name:"rev" service_name:"revision"}
{BuildImageStdout=image_name:"rev" service_name:"revision"}: Step 1 : FROM busybox
{BuildImageStdout=image_name:"rev" service_name:"revision"}:  ---> 7968321274dc
{BuildImageStdout=image_name:"rev" service_name:"revision"}: Step 2 : RUN mkdir /data
{BuildImageStdout=image_name:"rev" service_name:"revision"}:  ---> Using cache
{BuildImageStdout=image_name:"rev" service_name:"revision"}:  ---> 30337c708d45
{BuildImageStdout=image_name:"rev" service_name:"revision"}: Step 3 : COPY write_build_rev bin/
{BuildImageStdout=image_name:"rev" service_name:"revision"}:  ---> Using cache
{BuildImageStdout=image_name:"rev" service_name:"revision"}:  ---> c107c054ba1f
{BuildImageStdout=image_name:"rev" service_name:"revision"}: Successfully built c107c054ba1f
{BuildImageFinished=image_name:"rev" service_name:"revision"}
{ContainerRunStdout=step_name:"Set build version in local file data/BUILD_REV" service_name:"revision"}: Writing '2017-01-24 05:24:50.360018412 +0000 UTC' to file /data/BUILD_REV
{StepFinished=step_name:"Set build version in local file data/BUILD_REV" type:STEP_FINISHED_TYPE_SUCCESS}
{StepStarted=step_name:"Build app"}
{BuildImageStarted=image_name:"app" service_name:"app"}
{BuildImageStdout=image_name:"app" service_name:"app"}: Step 1 : FROM busybox
{BuildImageStdout=image_name:"app" service_name:"app"}:  ---> 7968321274dc
{BuildImageStdout=image_name:"app" service_name:"app"}: Step 2 : COPY data/BUILD_REV /
{BuildImageStdout=image_name:"app" service_name:"app"}:  ---> c5df86199db2
{BuildImageStdout=image_name:"app" service_name:"app"}: Removing intermediate container 24b62c75605f
{BuildImageStdout=image_name:"app" service_name:"app"}: Successfully built c5df86199db2
{BuildImageFinished=image_name:"app" service_name:"app"}
{StepFinished=step_name:"Build app" type:STEP_FINISHED_TYPE_SUCCESS}

⚡ docker run --rm app cat /BUILD_REV
2017-01-24 05:24:50.360018412 +0000 UTC

write_build_rev

#!/bin/sh

echo "Writing '$CI_STRING_TIME' to file /data/BUILD_REV"
echo "$CI_STRING_TIME" > /data/BUILD_REV