Gist 6042119

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✓ Published0🌍 Public

Last edited Jun 4, 2013

Created on Jul 19, 2013

This code example shows the implementation of a MongoDB data access layer in Scala using the ReactiveMongo and Play Framework libraries. It is organized into three traits and objects: `BaseDAO` defines common error handling logic via a `Recover` method that maps database operation results to either service exceptions or success values, handling specific database error codes like duplicate keys (11000); `DBQueryBuilder` provides utility methods for constructing MongoDB query operators such as `$set`, `$push`, `$pull`, and `$unset`; and `DocumentDAO` implements CRUD operations with automatic timestamps and ID generation for temporal models. The visualization demonstrates how error handling, query building, and data access patterns are structured in a Scala/Play application using ReactiveMongo.

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