[DCV-4060] [6.2] Document Sign in with Snowflake (OAuth)

docs/getting-started/create-account.md

@@ -29,7 +29,7 @@ To set up your Datacoves account, you will need to know your data warehouse prov
 
 | Data Warehouse Provider | Information Needed |
 | --- | --- |
-| Snowflake | Account, Warehouse, Database, Role, User, Password, Schema |
+| Snowflake | Account, Warehouse, Database, Role, Schema, and [a supported authentication method](/docs/how-tos/snowflake/snowflake-sign-in) |
 | Redshift | Host, Database, User, Schema, Password |
 | Databricks | Host, Schema, HTTP Path, Token |
 | BigQuery | Dataset, Keyfile JSON |

docs/how-tos/datacoves/how_to_connection_template.md

@@ -51,6 +51,9 @@ To create a new connection template click the `Create Connection Template` in th
 - `Database` - The default connection template database 
 - `Role`- The default connection template role
   ![Snowflake Connection Type](./assets/connections_editnew_snowflake.png)
+- `Client id` and `Client secret` (under **Sign in with Snowflake**) - Optional. Leave them empty to use Snowflake's
+  built-in sign-in, or enter the client of your own security integration. See
+  [Sign in with Snowflake](/docs/how-tos/snowflake/snowflake-sign-in).
 
 ## For Redshift, the available fields are: 
 

docs/how-tos/datacoves/how_to_service_connections.md

@@ -27,6 +27,8 @@ A Service Connection consists of the following fields:
     ![Delivery Mode](assets/service_connection_delivery.jpg). 
 - **Connection Template** The connection template to base this service connection on(i.e. the defaults)
   Depending on the template selected, additional fields will be displayed with the default values entered in the connection template. These default values can be overridden by toggling the indicator next to the given value. Enter the appropriate user, schema, and password. This is commonly a service account created specifically for Airflow and may differ between the development and production environment.
+  For Snowflake with the Airflow Connection delivery mode, the authentication mechanism can also be a key pair,
+  Sign in with Snowflake, or Workload identity. See [Sign in with Snowflake](/docs/how-tos/snowflake/snowflake-sign-in).
 
 ![Service Connection Connection Details](./assets/serviceconnection_editnew_details.png)
 

docs/how-tos/snowflake/snowflake-sign-in.md

@@ -0,0 +1,112 @@
+---
+title: "Sign in with Snowflake: OAuth for dbt and Airflow"
+sidebar_label: "Sign in with Snowflake"
+description: "Connect Datacoves to Snowflake with OAuth: Snowflake's built-in sign-in, your own security integration, and workload identity for Airflow service connections."
+sidebar_position: 81
+---
+# How to sign in to Snowflake with OAuth
+
+Datacoves connects dbt, the Snowflake extension, Datacoves Copilot and Airflow to Snowflake with a username/password + MFA, a
+key pair, or **Sign in with Snowflake**. Sign in with Snowflake works with Snowflake users and with your
+company's single sign-on, so it is the option for accounts where users have no password.
+
+It is offered in the setup wizard, in **Settings > Database Connections** and, for Airflow, in **Service
+Connections** with the Airflow Connection delivery mode. Airflow runs as the Snowflake user who signed in.
+
+![Sign in with Snowflake in the Database Connections settings](assets/snowflake-sign-in-settings.png)
+
+## Snowflake's built-in sign-in
+
+Needs no Snowflake admin setup. Datacoves signs in through Snowflake's `SNOWFLAKE$LOCAL_APPLICATION`
+integration. Check that your account has it:
+
+```sql
+SHOW SECURITY INTEGRATIONS LIKE 'SNOWFLAKE$LOCAL_APPLICATION';
+```
+
+![The Snowflake built-in sign-in in the setup wizard](assets/snowflake-sign-in-wizard.png)
+
+The sign-in opens in a dialog in Datacoves. Sign in the way you sign in to Snowflake. Passkeys aren't available
+in the dialog; pick another method, such as an authenticator app.
+
+![The Snowflake sign-in page in the Datacoves dialog](assets/snowflake-sign-in-dialog.png)
+
+## Your own security integration
+
+Use it when your admins want their own OAuth integration, with its own refresh token validity and role rules.
+A Snowflake admin with `ACCOUNTADMIN`, or a role with the `CREATE INTEGRATION` privilege, runs this once.
+Datacoves shows the same statements, with your cluster's redirect URI filled in and a copy button, in the
+setup wizard and on the connection template form.
+
+![The setup SQL for your own security integration in the setup wizard](assets/snowflake-sign-in-custom-integration.png)
+
+```sql
+CREATE SECURITY INTEGRATION DATACOVES_OAUTH
+  TYPE = OAUTH
+  ENABLED = TRUE
+  OAUTH_CLIENT = CUSTOM
+  OAUTH_CLIENT_TYPE = 'CONFIDENTIAL'
+  OAUTH_REDIRECT_URI = 'https://api.<your Datacoves domain>/api/setup/snowflake-oauth/callback'
+  OAUTH_ISSUE_REFRESH_TOKENS = TRUE
+  OAUTH_REFRESH_TOKEN_VALIDITY = 7776000
+  OAUTH_ENFORCE_PKCE = TRUE
+  OAUTH_ANY_ROLE_MODE = 'ENABLE'
+  OAUTH_USE_SECONDARY_ROLES = IMPLICIT;
+
+SELECT SYSTEM$SHOW_OAUTH_CLIENT_SECRETS('DATACOVES_OAUTH');
+```
+
+- `OAUTH_CLIENT = CUSTOM` and `OAUTH_CLIENT_TYPE = 'CONFIDENTIAL'` make an integration that Datacoves
+  authenticates to with a client id and secret.
+- `OAUTH_REDIRECT_URI` is where Snowflake sends the browser after sign-in. It is `https://api.` plus the
+  domain of your Datacoves cluster, the domain in your Datacoves address, and the path above.
+- `OAUTH_ISSUE_REFRESH_TOKENS` and `OAUTH_REFRESH_TOKEN_VALIDITY` let dbt and Airflow keep working without
+  signing in again. The validity is in seconds: 86400 (1 day) to 7776000 (90 days). Snowflake Support raises
+  the maximum on request.
+- `OAUTH_ENFORCE_PKCE` requires PKCE on every sign-in.
+- `OAUTH_ANY_ROLE_MODE` and `OAUTH_USE_SECONDARY_ROLES` let dbt switch roles inside a session, as it does with
+  a password or a key pair.
+- `SYSTEM$SHOW_OAUTH_CLIENT_SECRETS` returns the client id and secret. Enter them in the setup wizard, or on
+  the connection template under **Sign in with Snowflake**. Every connection on that template then signs in
+  through this integration.
+
+Snowflake blocks `ACCOUNTADMIN`, `SECURITYADMIN`, `GLOBALORGADMIN` and `ORGADMIN` in OAuth sessions by
+default. Use another role for dbt and Airflow.
+
+## When a sign-in expires
+
+A sign-in lasts as long as the integration's `OAUTH_REFRESH_TOKEN_VALIDITY`. When one expires, is about to
+expire, or Snowflake revokes it, the Launchpad shows a banner with **Sign in again**, and the connection lists
+show a badge. Signing in again restarts your workspace with the new sign-in. An Airflow service connection is
+signed in again from its edit page.
+
+Single-use refresh tokens (`OAUTH_SINGLE_USE_REFRESH_TOKENS_REQUIRED = TRUE`) are not supported. Datacoves
+shows the `ALTER SECURITY INTEGRATION` statement that turns them off when it finds them.
+
+## Workload identity for Airflow
+
+An Airflow service connection can sign in with no secret at all: choose the Airflow Connection delivery mode
+and **Workload identity** as the authentication mechanism, and Snowflake trusts your environment's
+Airflow as one service user. The form shows the statement to run, with the issuer and subject of your
+environment filled in:
+
+```sql
+CREATE USER AIRFLOW_SERVICE
+  WORKLOAD_IDENTITY = (
+    TYPE = OIDC
+    ISSUER = '<issuer shown in the form>'
+    SUBJECT = '<subject shown in the form>'
+  )
+  TYPE = SERVICE
+  DEFAULT_ROLE = TRANSFORMER;
+
+GRANT ROLE TRANSFORMER TO USER AIRFLOW_SERVICE;
+```
+
+Turn Airflow on in the environment before you create the connection, so the form can show the issuer and
+subject.
+
+## Network policies
+
+Token requests come from Datacoves' addresses, so Snowflake network policies have to allow them. The setup SQL
+panel lists the addresses when your cluster has them configured.