Deployment strategies

A strategy prepares the host before deploy_command runs, by writing release metadata where your deploy tooling expects it. Strategies run on every forward deployment attempt and on every rollback attempt.

strategy.type	Effect
none (default)	Nothing; deploy_command runs directly.
env_file	Writes the image tag into an env file.

If you do not need a file, you may not need a strategy at all: deploy_command already receives the release in WORKLOAD_* environment variables.

env_file

strategy:
  type: env_file
  env_file_path: /opt/my-app/.env.deploy
  image_tag_key: IMAGE_TAG   # optional, this is the default

Before each deploy, reconD sets this line in the file:

IMAGE_TAG=<image_tag from deployment metadata>

• If the file does not exist, reconD creates it, along with missing parent directories (mode 0750).
• If the key already exists, its line is replaced in place. Lines written as export IMAGE_TAG=... are recognized and replaced.
• Every other line, including comments, is kept as is.
• The file is written atomically (written to <path>.tmp, then renamed) with mode 0600.

The release's metadata must include image_tag; otherwise the strategy fails, which counts as a deployment failure.

Rollback relies on immutable tags

This strategy writes only the tag, so a rollback redeploys whatever the previous release's tag points to now. If you reuse tags such as prod-latest, that is the image that just failed. Use immutable tags, for example prod-sha-<commit>, or deploy by digest with $WORKLOAD_IMAGE@$WORKLOAD_MANIFEST_DIGEST.

This is useful when the deploy command delegates to a script or Compose file that reads the tag from an env file. See the Compose example.

TIP

Keep the strategy's env file separate from files that hold secrets or other settings, so that reconD only ever rewrites deployment metadata.