Hashicorp Vault Secrets Backend¶
To enable Hashicorp vault to retrieve Airflow connection/variable, specify VaultBackend
as the backend in [secrets] section of airflow.cfg.
Here is a sample configuration:
[secrets]
backend = airflow.providers.hashicorp.secrets.vault.VaultBackend
backend_kwargs = {"connections_path": "connections", "variables_path": "variables", "mount_point": "airflow", "url": "http://127.0.0.1:8200"}
The default KV version engine is 2, pass kv_engine_version: 1 in backend_kwargs if you use
KV Secrets Engine Version 1.
You can also set and pass values to Vault client by setting environment variables. All the environment variables listed at https://www.vaultproject.io/docs/commands/#environment-variables are supported.
Hence, if you set VAULT_ADDR environment variable like below, you do not need to pass url
key to backend_kwargs:
export VAULT_ADDR="http://127.0.0.1:8200"
Optional lookup¶
Optionally connections, variables, or config may be looked up exclusive of each other or in any combination. This will prevent requests being sent to Vault for the excluded type.
If you want to look up some and not others in Vault you may do so by setting the relevant *_path parameter of the ones to be excluded as null.
For example, if you want to set parameter connections_path to "airflow-connections" and not look up variables, your configuration file should look like this:
[secrets]
backend = airflow.providers.hashicorp.secrets.vault.VaultBackend
backend_kwargs = {"connections_path": "airflow-connections", "variables_path": null, "mount_point": "airflow", "url": "http://127.0.0.1:8200"}
Storing and Retrieving Connections¶
If you have set connections_path as connections and mount_point as airflow, then for a connection id of
smtp_default, you would want to store your secret as:
vault kv put airflow/connections/smtp_default conn_uri=smtps://user:host@relay.example.com:465
Note that the Key is conn_uri, Value is postgresql://airflow:airflow@host:5432/airflow and
mount_point is airflow.
You can make a mount_point for airflow as follows:
vault secrets enable -path=airflow -version=2 kv
Verify that you can get the secret from vault:
❯ vault kv get airflow/connections/smtp_default
====== Metadata ======
Key Value
--- -----
created_time 2020-03-19T19:17:51.281721Z
deletion_time n/a
destroyed false
version 1
====== Data ======
Key Value
--- -----
conn_uri smtps://user:host@relay.example.com:465
The value of the Vault key must be the connection URI representation of the connection object to get connection.
Storing and Retrieving Variables¶
If you have set variables_path as variables and mount_point as airflow, then for a variable with
hello as key, you would want to store your secret as:
vault kv put airflow/variables/hello value=world
Verify that you can get the secret from vault:
❯ vault kv get airflow/variables/hello
====== Metadata ======
Key Value
--- -----
created_time 2020-03-28T02:10:54.301784Z
deletion_time n/a
destroyed false
version 1
==== Data ====
Key Value
--- -----
value world
Note that the secret Key is value, and secret Value is world and
mount_point is airflow.