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Postgres assets package

The Postgres assets package crawls PostgreSQL assets and publishes them to Atlan for discovery.

Direct extraction

Will create a new connection

This should only be used to create the workflow the first time. Each time you run this method it will create a new connection and new assets within that connection — which could lead to duplicate assets if you run the workflow this way multiple times with the same settings.

Instead, when you want to re-crawl assets, re-run the existing workflow (see Re-run existing workflow below).

To crawl assets directly from PostgreSQL using basic authentication:

Direct extraction from PostgreSQL
Workflow postgres = PostgreSQLCrawler.directBasicAuth( // (1)
"production", // (2)
"postgres.x9f0ve2k1kvy.ap-south-1.rds.amazonaws.com", // (3)
5432, // (4)
"postgres", // (5)
"nCkM685ZH9g4fVICMs6H", // (6)
"demo_db", // (7)
List.of(client.getRoleCache().getIdForName("$admin")), // (8)
null,
null,
true, // (9)
true, // (10)
10000L, // (11)
Map.of("demo_db", List.of("demo")), // (12)
null); // (13)
WorkflowResponse response = postgres.run(); // (14)
  1. The PostgreSQLCrawler package will create a workflow to crawl assets from PostgreSQL. The directBasicAuth() method creates a workflow for crawling assets directly from PostgreSQL.

  2. You must provide a name for the connection that the PostgreSQL assets will exist within.

  3. You must provide the hostname of your PostgreSQL instance.

  4. You must specify the port number of the PostgreSQL instance (use 5432 for the default).

  5. You must provide your PostgreSQL username.

  6. You must provide your PostgreSQL password.

  7. You must specify the name of the PostgreSQL database you want to crawl.

  8. You must specify at least one connection admin, either:

    • everyone in a role (in this example, all $admin users)
    • a list of groups (names) that will be connection admins
    • a list of users (names) that will be connection admins
  9. You can specify whether you want to allow queries to this connection (true, as in this example) or deny all query access to the connection (false).

  10. You can specify whether you want to allow data previews on this connection (true, as in this example) or deny all sample data previews to the connection (false).

  11. You can specify a maximum number of rows that can be accessed for any asset in the connection.

  12. You can also optionally specify the set of assets to include in crawling. For PostgreSQL assets, this should be specified as a map keyed by database name with values as a list of schemas within that database to crawl. (If set to null, all databases and schemas will be crawled.)

  13. You can also optionally specify the list of assets to exclude from crawling. For PostgreSQL assets, this should be specified as a map keyed by database name with values as a list of schemas within the database to exclude. (If set to null, no assets will be excluded.)

  14. You can then run the workflow using the run() method on the object you've created. Because this operation will execute work in Atlan, you must provide it an AtlanClient through which to connect to the tenant.

    Workflows run asynchronously

Remember that workflows run asynchronously. See the packages and workflows introduction for details on how you can check the status and wait until the workflow has been completed. :::

IAM user authentication

Will create a new connection

This should only be used to create the workflow the first time. Each time you run this method it will create a new connection and new assets within that connection — which could lead to duplicate assets if you run the workflow this way multiple times with the same settings.

Instead, when you want to re-crawl assets, re-run the existing workflow (see Re-run existing workflow below).

To crawl assets directly from PostgreSQL using IAM user authentication:

Coming soon

IAM role authentication

Will create a new connection

This should only be used to create the workflow the first time. Each time you run this method it will create a new connection and new assets within that connection — which could lead to duplicate assets if you run the workflow this way multiple times with the same settings.

Instead, when you want to re-crawl assets, re-run the existing workflow (see Re-run existing workflow below).

To crawl assets directly from PostgreSQL using IAM role authentication:

Coming soon

Offline extraction

Will create a new connection

This should only be used to create the workflow the first time. Each time you run this method it will create a new connection and new assets within that connection — which could lead to duplicate assets if you run the workflow this way multiple times with the same settings.

Instead, when you want to re-crawl assets, re-run the existing workflow (see Re-run existing workflow below).

To crawl PostgeSQL assets from the S3 bucket:

Coming soon

Re-run existing workflow

To re-run an existing workflow for PostgreSQL assets:

Re-run existing PostgreSQL workflow
List<WorkflowSearchResult> existing = WorkflowSearchRequest // (1)
.findByType(client, PostgreSQLCrawler.PREFIX, 5); // (2)
// Determine which of the results is the PostgreSQL workflow you want to re-run...
WorkflowRunResponse response = existing.get(n).rerun(client); // (3)
  1. You can search for existing workflows through the WorkflowSearchRequest class.

  2. You can find workflows by their type using the findByType() helper method and providing the prefix for one of the packages. In this example, we do so for the PostgreSQLCrawler. (You can also specify the maximum number of resulting workflows you want to retrieve as results.)

  3. Once you've found the workflow you want to re-run, you can simply call the rerun() helper method on the workflow search result. The WorkflowRunResponse is just a subtype of WorkflowResponse so has the same helper method to monitor progress of the workflow run. Because this operation will execute work in Atlan, you must provide it an AtlanClient through which to connect to the tenant.

    • Optionally, you can use the rerun(client, true) method with idempotency to avoid re-running a workflow that is already in running or in a pending state. This will return details of the already running workflow if found, and by default, it is set to false
    Workflows run asynchronously

Remember that workflows run asynchronously. See the packages and workflows introduction for details on how you can check the status and wait until the workflow has been completed. :::

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