Glean

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Glean is a system for working with facts about source code. You can use it for:

• Collecting and storing detailed information about code structure. Glean is designed around an efficient storage model that enables storing information about code at scale.

• Querying information about code, to power tools and experiences from online IDE features to offline code analysis.

Status

Glean is pre-release software. There are many rough edges; there are limited language indexers available initially; the build system is not as smooth as we would like. However, we want to make it available for you to experiment with and contribute to.

We'd love to hear feedback! If you run into problems or have suggestions please file an issue.

Language coverage

There is currently full support for:

• C++ and C
• Hack
• Haskell
• JavaScript/Flow

We are actively adding support for:

• Rust

Indexers for these languages exist but aren't in the open source release yet; we hope to make these available in the future:

• Python
• Objective-C
• Java
• Erlang
• Thrift
• Buck

We have also added support for the LSIF code indexing format. The following LSIF indexers are supported:

• TypeScript
• Go
• Rust
• Java

LSIF indexers are more limited than full language indexers, but are sufficient for common code navigation and symbol search use cases.

License

Glean is licensed under a BSD LICENSE.

Contributing

We'd love to have your help developing Glean. Please submit pull requests on github, and note that we need contributors to sign the Contributor license agreement before we can accept your pull request.

Style guide: for Haskell code, we use hlint to check for style issues. Lines wrap at 80 columns. Code should be -Wall clean. For C++, code should compile with Clang or GCC.

Building

See Building Glean.

Docker demo

For demo of the react codebase with hyperlinks powered by glean run docker run -ti -p8888:8888 ghcr.io/facebookincubator/glean/demo

Try out on your own codebase with a .flowconfig by running docker run -ti -p8888:8888 -v __YOUR_CODE_DIR__:/glean_demo/code ghcr.io/facebookincubator/glean/demo

Play round using the glean binaries in a shell by running docker run -ti -p8888:8888 ghcr.io/facebookincubator/glean/demo shell