Validate pipeline changes with dry run

Use the dry run validation endpoint to validate pipeline YAML before committing to Git.

The dry run validation endpoint allows you to validate pipeline YAML changes while editing files in Git. This helps catch configuration errors before you commit changes to your repository.

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What you will learn in this topic

• How to use the dry run validation endpoint to validate pipeline YAML.

• How to read the validation response for valid and invalid pipelines.

• How to recognize the limitations of dry run validation.

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What is dry run validation?

Dry run validation is an API endpoint that validates pipeline YAML without executing the pipeline. Use this endpoint to validate your pipeline changes while editing YAML files in Git before saving them.

The validation performs:

• YAML schema validation: Verifies the pipeline structure and syntax.

• Template expansion: Validates template references and expands templates during validation.

• Policy evaluation: Evaluates OPA policies for pipeline on save or on run.

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Use the API endpoint

Endpoint

POST /pipeline/api/v1/orgs/{org}/projects/{project}/dry-run

Request parameters

{
  "pipeline_identifier": "string",
  "pipeline_yaml": "string",
  "branch": "string"
}

Parameter	Required	Description
pipeline_yaml	Yes	Complete pipeline YAML as a string
pipeline_identifier	Yes	Unique identifier of the pipeline
branch	No	Git branch where the pipeline is stored. Optional for an inline pipeline; include it for a Git-backed pipeline

The account, organization, and project identifiers are supplied in the URL path (org, project) and the Harness-Account header, not in the request body.

Example request

curl --location 'https://app.harness.io/pipeline/api/v1/orgs/default/projects/MyProject/dry-run' \
--header 'Accept: application/json' \
--header 'Content-Type: application/json' \
--header 'Harness-Account: <account-id>' \
--data '{
  "pipeline_identifier": "mypipeline",
  "pipeline_yaml": "pipeline:\n  name: my-pipeline\n  identifier: mypipeline\n  ...",
  "branch": "main"
}'

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Response format

Successful validation

When the pipeline YAML is valid, the endpoint returns a success response:

{
  "is_valid": true,
  "validation": []
}

Validation errors

When validation fails, the response includes specific error messages indicating what needs to be fixed:

{
  "is_valid": false,
  "validation": [
    {
      "validation_type": "string",
      "entity_type": "string",
      "entity_identifier": "string",
      "error_message": "Following yaml paths could not be parsed: ...",
      "hint": "string"
    }
  ]
}

Each entry in the validation array describes one validation result. The endpoint returns a validation_type and entity_type for each entry.

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Limitations

The dry run validation cannot validate:

• Expressions: Pipeline expressions are not validated by the dry run endpoint.

• Delegate availability: Whether delegates are available for execution.

• Cloud provider credentials: Validity of credentials at execution time.

• Artifact connectivity: Whether artifact sources are accessible.

• Service manifests: Internal validity of Kubernetes manifests or other service definitions.

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Next steps

You have validated pipeline YAML with the dry run endpoint. Continue with the following:

• Pipeline YAML quickstart: Learn the pipeline YAML schema.

• Input sets and overlays: Manage runtime inputs for your pipelines.