Using AWS S3 to Store DevStream State

Tiexin Guo | 郭铁心 included in DevStream How-To English Articles

2022-05-30 480 words One minute

Contents

In our latest release v0.6.0, using AWS S3 to store DevStream state is supported.

In this blog, we are going to demonstrate the usage of AWS S3 to store DevStream’s state files.

Terminology

State: if you don’t already know about DevStream state, please read this doc and this blog helps, too.

Backend: where to actually store the state file. It can be either local or s3 at the moment.

Configuration

In the main config file, we have a section to configure the state. Currently, local and S3 are supported.

Local example:

varFile: variables-gitops.yaml

toolFile: tools-gitops.yaml

state:
  backend: local
  options:
    stateFile: devstream.state

S3 example:

varFile: variables-gitops.yaml

toolFile: tools-gitops.yaml

state:
  backend: s3
  options:
    bucket: devstream-remote-state
    region: ap-southeast-1
    key: devstream.state

Config File Examples

In this demo, we use the following configs:

config.yaml:

varFile: variables-gitops.yaml

toolFile: tools-gitops.yaml

state:
  backend: s3
  options:
    bucket: devstream-test-remote-state
    region: ap-southeast-1
    key: devstream.state

variables-gitops.yaml:

githubUsername: IronCore864
repoName: dtm-test-go
defaultBranch: main

dockerhubUsername: ironcore864

argocdNameSpace: argocd
argocdDeployTimeout: 5m

tools-gitops.yaml:

tools:
- name: github-repo-scaffolding-golang
  instanceID: default
  options:
    owner: [[ githubUsername ]]
    org: ""
    repo: [[ repoName ]]
    branch: [[ defaultBranch ]]
    image_repo: ^[ dockerhubUsername ]/_{[ repoName}]

Getting Started

Before reading on, now is a good time to check if you have configured your AWS related environment variables correctly or not.

For macOS/Linux users, do:

export AWS_ACCESS_KEY_ID=ID_HERE
export AWS_SECRET_ACCESS_KEY=SECRET_HERE
export AWS_DEFAULT_REGION=REGION_HERE

For more information, see the official document here.

Apply

Then let’s run dtm apply:

tiexin@mbp ~/work/devstream-io/devstream $ ./dtm apply
2022-05-30 17:07:59 ℹ [INFO]  Apply started.
2022-05-30 17:07:59 ℹ [INFO]  Using dir <.devstream> to store plugins.
2022-05-30 17:07:59 ℹ [INFO]  Using s3 backend. Bucket: devstream-test-remote-state, region: ap-southeast-1, key: devstream.state.
2022-05-30 17:08:00 ℹ [INFO]  Tool (github-repo-scaffolding-golang/default) found in config but doesn't exist in the state, will be created.
Continue? [y/n]
Enter a value (Default is n): y

2022-05-30 17:08:08 ℹ [INFO]  Start executing the plan.
2022-05-30 17:08:08 ℹ [INFO]  Changes count: 1.
2022-05-30 17:08:08 ℹ [INFO]  -------------------- [  Processing progress: 1/1.  ] --------------------
2022-05-30 17:08:08 ℹ [INFO]  Processing: (github-repo-scaffolding-golang/default) -> Create ...
2022-05-30 17:08:12 ℹ [INFO]  The repo dtm-test-go has been created.
2022-05-30 17:08:29 ✔ [SUCCESS]  Tool (github-repo-scaffolding-golang/default) Create done.
2022-05-30 17:08:29 ℹ [INFO]  -------------------- [  Processing done.  ] --------------------
2022-05-30 17:08:29 ✔ [SUCCESS]  All plugins applied successfully.
2022-05-30 17:08:29 ✔ [SUCCESS]  Apply finished.

As we can see from the output, the S3 backend is used, and it also shows the bucket and key you are using, and in which region this bucket lives.

Checking the State File

After apply, let’s download the state file from S3 and check it out:

tiexin@mbp ~/work/devstream-io/devstream $ aws s3 cp s3://devstream-test-remote-state/devstream.state .

And if we open the downloaded file, we will see something similar to the following:

github-repo-scaffolding-golang_default:
  name: github-repo-scaffolding-golang
  instanceid: default
  dependson: []
  options:
    branch: main
    image_repo: ironcore864/dtm-test-go
    org: ""
    owner: IronCore864
    repo: dtm-test-go
  resource:
    org: ""
    outputs:
      org: ""
      owner: IronCore864
      repo: dtm-test-go
      repoURL: https://github.com/IronCore864/dtm-test-go.git
    owner: IronCore864
    repoName: dtm-test-go

which is exactly the same as if we were using the local backend to store state.

Like this quick tutorial? Then I suggest to read more of our latest DevOps blogs: