Run Apache Airflow DAG and retrieve XCom value
# Run Apache Airflow DAG and Retrieve XCom Value
## What this workflow does
This workflow integrates the Apache Airflow API [DAGRun](https://airflow.apache.org/docs/apache-airflow/2.10.5/stable-rest-api-ref.html#tag/DAGRun) and [XCom](https://airflow.apache.org/docs/apache-airflow/2.10.5/stable-rest-api-ref.html#tag/XCom). It enables n8n to trigger Airflow DAGs and retrieve the execution results.
## Preparation:
1. **Update Airflow API Link Prefix**
- Navigate to the `airflow-api` node.
- Update the prefix of the Airflow API link in the format: `http(s)://ip:port`.
- Example: `https://airflow.example.com`
2. **Configure Authentication**
- Go to the `Airflow: dag_run` node.
- Update the `Basic Auth` credentials with your Airflow username and password.
- Repeat this step for `Airflow: dag_run - state` and `Airflow: dag_run - get result` nodes.
**Security Note:** Using Basic Authentication requires storing credentials in plaintext. If possible, consider using API Keys or Tokens for enhanced security.
- An example is setting Airflow's [API Authentication](https://airflow.apache.org/docs/apache-airflow-providers-fab/stable/auth-manager/api-authentication.html) to [basic\_auth](https://airflow.apache.org/docs/apache-airflow-providers-fab/stable/auth-manager/api-authentication.html#basic-authentication). Choose other authentication methods if needed.
- Ensure the user account has the following permissions: `can create on DAG Runs`, `can read on DAG Runs`, `can read on XComs`, `can edit on DAGs`, and `can read on DAGs`.
## How to Use:
To execute this workflow, use the **Execute Sub-workflow** node with the following input parameters:
- **dag\_id**: The DAG ID (name) in Airflow that you want to trigger.
- **task\_id**: The Task ID (name) from which you want to retrieve the XCom return\_value.
- **conf**: Input data for the Airflow DAG run.
- **wait**: Delay (in seconds) between each `Airflow: dag_run - state` check.
- **wait\_time**: The maximum time (in seconds) to wait for `Airflow: dag_run - state` before returning an error.
## Output:
- The workflow returns the XCom result from `Airflow: dag_run - get result`.
- The XCom `return_value` is stored in the `value` field.
