BigQuery Unit Testing for Isolated Environments

About The Project

Making BigQuery unit tests work when your local/isolated environment cannot connect to BigQuery APIs is challenging. This project demonstrates how you can stub/mock your BigQuery responses for unit test cases.

The scenario for which this solution will work:

• You need to unit test a function which calls on BigQuery (SQL,DDL,DML)
• You don’t actually want to run the Query/DDL/DML command, but just work off the results
• You want to run several such commands, and want the output to match BigQuery output format

The idea in a nutshell:

• Store BigQuery results as Serialized Strings in a local file, where the query (md5 hashed) is the key. (see RunSampleQuery.java and query.properties)
• In your unit test cases, mock BigQuery results to retrieve the previously serialized version of the Query output (see BigqueryTesting.java)

Reach out to me for questions or suggestions.

Built With

• Mockito

Getting Started

1. Modify and run RunSampleQuery.java
2. Modify and Run Junit test cases
3. Copy this approach to your project

Prerequisites

To run RunSampleQuery.java you need to have been authenticated via GoogleCloud CLI. RunSampleQuery.java cannot be run in an isolated environment but the Unit Tests can run without network connectivity.

License

Distributed under the MIT License. See LICENSE for more information.

Contact

Ajay Prabhakar - @hicoder - ajay@hicoder.net