Bring your towel and join one of the fastest growing data communities. Welcome to our second-generation open source orchestration platform, a completely rethought approach to dataflow automation.

Prefect Community

<@ULVA73B9P> do we have a way to dry run deployments so we can validate they pass before we deploy in cicd?

:white_check_mark: thought for 151.5 seconds

Short answer: *not natively, no.*

In Prefect 3.x, `prefect deploy` does *not* have a `--dry-run` option. I verified the CLI help, and there’s no dry-run/plan mode there.

What you *can* do in CI/CD is validate the deployment inputs *before* actually creating the deployment:

*Recommended validation steps*
1. *Validate `prefect.yaml` parses and matches Prefect’s schema*
2. *Validate each flow entrypoint can be imported*
3. *Optionally validate against a staging/test Prefect workspace*
4. Only then run `prefect deploy`

A practical pattern is:

```bash
python validate_before_deploy.py
prefect deploy --prefect-file prefect.yaml --name my-deployment
```

A useful validation script is:

```python
from pathlib import Path
import sys
import yaml
from prefect.flows import load_flow_from_entrypoint
from prefect.cli.deploy._config import _load_deploy_configs_and_actions
from rich.console import Console

console = Console()

def main():
    prefect_file = Path("prefect.yaml")

    if not prefect_file.exists():
        console.print("prefect.yaml not found", style="red")
        sys.exit(1)

    try:
        with open(prefect_file) as f:
            config = yaml.safe_load(f)
        console.print("YAML syntax OK", style="green")
    except Exception as e:
        console.print(f"YAML parse failed: {e}", style="red")
        sys.exit(1)

    try:
        deploy_configs, _ = _load_deploy_configs_and_actions(
            prefect_file=prefect_file,
            console=console,
        )
        console.print(f"Deployment config OK: {len(deploy_configs)} deployment(s)", style="green")
    except Exception as e:
        console.print(f"Deployment config invalid: {e}", style="red")
        sys.exit(1)

    for dep in config.get("deployments", []):
        entrypoint = dep.get("entrypoint")
        if entrypoint:
            try:
                flow = load_flow_from_entrypoint(entrypoint)
                console.print(f"Entrypoint OK: {entrypoint} -&gt; {flow.name}", style="green")
            except Exception as e:
                console.print(f"Entrypoint failed: {entrypoint}: {e}", style="red")
                sys.exit(1)

if __name__ == "__main__":
    main()
```

A few notes:
- This catches *most* config/import problems early.
- It does *not* fully simulate the server-side creation of the deployment.
- If you want higher confidence, the best “real” dry run is deploying to a *staging workspace* first.

I also verified the CLI command exists here:
- `prefect deploy --help`

Relevant docs:
- <https://docs.prefect.io/v3/deploy/index|Prefect 3 deployment docs>
- <https://docs.prefect.io/v3/how-to-guides/deployments/prefect-yaml|prefect.yaml guide>

If you want, I can give you a *GitHub Actions* or *GitLab CI* example for this validation flow.