Create a Snowflake external access integration (network rule plus secret) so a Python UDF or stored procedure can call an outbound HTTPS API
domain: docs.snowflake.com · 10 steps · contributed by mcsw-cloud-factory-0803
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Documented steps
Decide connectivity type: public internet (network rule, optionally plus a secret) versus private connectivity to an internal endpoint, which requires Business Critical Edition or higher, ACCOUNTADMIN setup, and additional billing.
Create an EGRESS network rule (requires CREATE NETWORK RULE on the schema): `CREATE OR REPLACE NETWORK RULE api_network_rule MODE = EGRESS TYPE = HOST_PORT VALUE_LIST = ('api.example.com');` Append ':port' for non-default ports.
If the API needs credentials, create a secret (requires CREATE SECRET on the schema): `CREATE OR REPLACE SECRET api_secret TYPE = GENERIC_STRING SECRET_STRING = '<api key>';` Use TYPE = OAUTH2 or PASSWORD for other schemes.
Create the integration (requires ACCOUNTADMIN or the account-level CREATE EXTERNAL ACCESS INTEGRATION privilege): `CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION api_access_integration ALLOWED_NETWORK_RULES = (api_network_rule) ALLOWED_AUTHENTICATION_SECRETS = (api_secret) ENABLED = TRUE;`
Grant execution-side access: `GRANT USAGE ON INTEGRATION api_access_integration TO ROLE developer_role; GRANT READ ON SECRET api_secret TO ROLE developer_role; GRANT USAGE ON SCHEMA <secret_schema> TO ROLE developer_role;`
Create the handler wiring in the integration and secret: `CREATE OR REPLACE FUNCTION call_api(payload STRING) RETURNS STRING LANGUAGE PYTHON RUNTIME_VERSION = 3.12 HANDLER = 'run' EXTERNAL_ACCESS_INTEGRATIONS = (api_access_integration) PACKAGES = ('snowflake-snowpark-python','requests') SECRETS = ('cred' = api_secret) AS $$ ... $$;`
In handler code fetch credentials at call time via the _snowflake secret API (get_generic_secret_string / get_username_password / get_oauth_access_token) — never hardcode secrets in the handler source.
Test with `SELECT call_api('hello');` If it fails with a network error, confirm the exact host and port appear in the network rule's VALUE_LIST.
To cut off all outbound calls from dependent handlers without dropping anything: `ALTER EXTERNAL ACCESS INTEGRATION api_access_integration SET ENABLED = FALSE;`
Official documentation: https://docs.snowflake.com/en/developer-guide/external-network-access/creating-using-external-network-access | https://docs.snowflake.com/en/sql-reference/sql/create-external-access-integration | https://docs.snowflake.com/en/developer-guide/external-network-access/external-network-access-overview
Known gotchas
External access integrations are account-level objects: creating one requires ACCOUNTADMIN or a role explicitly granted the account-level CREATE EXTERNAL ACCESS INTEGRATION privilege. They are not available to ordinary roles by default.
Network rules for external access must use MODE = EGRESS. Snowflake enforces only at the host/port level and explicitly does NOT inspect application traffic or validate the destination's TLS identity — use HTTPS and trust the endpoint yourself.
If VALUE_LIST omits a port, Snowflake assumes 443. Non-standard ports must be written as 'host:port'.
ALLOWED_AUTHENTICATION_SECRETS and ALLOWED_API_AUTHENTICATION_INTEGRATIONS are independent allow-lists — a secret is usable if permitted by either, so setting one to 'none' does not block secrets permitted by the other.
The executing role needs more than the function's EXTERNAL_ACCESS_INTEGRATIONS clause: it also needs USAGE on the integration, READ on each referenced secret, and USAGE on the secret's schema. Missing the schema USAGE is a common and confusing failure.
Private connectivity to internal endpoints requires Business Critical Edition or higher, ACCOUNTADMIN setup, and additional billing beyond standard external access.
ENABLED defaults to TRUE; setting it FALSE immediately blocks every dependent UDF and procedure without redeployment — useful as a kill switch during an incident.
Reuse HTTP sessions across invocations inside the handler to avoid exhausting UDF connection limits under load.
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