Hound

Hound is an extremely fast source code search engine. The core is based on this article (and code) from Russ Cox: Regular Expression Matching with a Trigram Index. Hound itself is a static React frontend that talks to a Go backend. The backend keeps an up-to-date index for each repository and answers searches through a minimal API. Here it is in action:

Quick Start Guide

Building hound

0. Install go (minimum version required: 1.16) and npm

1. Clone the repository and run make.

git clone https://github.com/hound-search/hound.git
cd hound
make

The resulting binaries (hound, houndd) can be found in the .build/bin/ directory.

2. Create a config.json file and use it to list your repositories. Check out our example-config.json to see how to set up various types of repositories. For example, we can configure Hound to search its own source code using the config found in default-config.json:

{
  "dbpath" : "db",
  "repos" : {
    "Hound" : {
      "url" : "https://github.com/hound-search/hound.git",
      "vcs-config" : {
        "ref" : "main"
      }
    }
  }
}

A complete list of available config options can be found here.

3. Run the Hound server with houndd in the same directory as your config.json. You should see output similar to:

2015/03/13 09:07:42 Searcher started for statsd
2015/03/13 09:07:42 Searcher started for Hound
2015/03/13 09:07:42 All indexes built!
2015/03/13 09:07:42 running server at http://localhost:6080

4. By default, hound hosts a web ui at http://localhost:6080 . Open it in your browser, and start searching.

Using Docker (1.14+)

0. Install docker if you don't have it. We need at least Docker >= 1.14.

1. Create a config.json file and use it to list your repositories. Check out our example-config.json to see how to set up various types of repositories. For example, we can configure Hound to search its own source code using the config found in default-config.json.

Run with image from github

docker run -d -p 6080:6080 --name hound -v $(pwd):/data ghcr.io/hound-search/hound:latest

You should be able to navigate to http://localhost:6080/ as usual.

Build image and container yourself

0. Clone repository

git clone https://github.com/hound-search/hound.git
cd hound

1. Build the image

docker build . --tag=hound

2. Create the container

docker create -p 6080:6080 --name hound -v $(pwd):/data hound

3. Starting and stopping the container

docker start hound
docker stop hound

Running in Production

There are no special flags to run Hound in production. You can use the --addr=:6880 flag to control the port to which the server binds. Currently, Hound does not support TLS as most users simply run Hound behind either Apache or nginx. However, we are open to contributions to add TLS support.

Why Another Code Search Tool?

We've used many similar tools in the past, and most of them are either too slow, too hard to configure, or require too much software to be installed. Which brings us to...

Requirements

• Go 1.16+

Yup, that's it. You can proxy requests to the Go service through Apache/nginx/etc., but that's not required.

Support

Currently Hound is only tested on MacOS and CentOS, but it should work on any *nix system. Hound on Windows is not supported but we've heard it compiles and runs just fine (although it helps to exclude your data folder from Windows Search Indexer).

Hound supports the following version control systems:

• Git - This is the default
• Mercurial - use "vcs" : "hg" in the config
• SVN - use "vcs" : "svn" in the config
• Bazaar - use "vcs" : "bzr" in the config
• Local - use "vcs" : "local" in the config

See config-example.json for examples of how to use each VCS.

Private Repositories

There are a couple of ways to get Hound to index private repositories:

• Use the local pseudo-vcs driver. This allows you to index a local directory. You can set "watch-changes" : true to calculate a recursive hash of all the files in the directory and automatically re-index.
• Use the file:// protocol. This allows you to index a local clone of a repository. The downside here is that the polling to keep the repo up to date will not work. (This also doesn't work on local folders that are not of a supported repository type.) If you're using Docker, you must mount a volume to your repository (e.g., -v $(pwd)/src:/src) and use the relative path to the repo in your configuration.
• Use SSH style URLs in the config: "url" : "git@github.com:foo/bar.git". As long as you have your SSH keys set up on the box where Hound is running this will work.

Keeping Repos Updated

By default Hound polls the URL in the config for updates every 30 seconds. You can override this value by setting the ms-between-poll key on a per repo basis in the config. If you are indexing a large number of repositories, you may also be interested in tweaking the max-concurrent-indexers property. You can see how these work in the example config.

Editor Integration

Currently the following editors have plugins that support Hound:

• Sublime Text
• Vim
• Emacs
• Visual Studio Code

Hacking on Hound

Editing & Building

Requirements:

• make
• npm (Usuall npm comes bundled with Node.js. If that's not the case on the system you're using, you can get it here)

git clone https://github.com/hound-search/hound.git
cd hound
make

The hound executables will be available in .build/bin.

Testing

There are an increasing number of tests in each of the packages in Hound. Please make sure these pass before uploading your Pull Request. You can run the tests with the following command. To run the entire test suite, use:

make test

If you want to just run the JavaScript test suite, use:

npm test

Any Go files that end in _test.go are assumed to be test files. Similarly, any JavaScript files that ends in .test.js are automatically run by Jest, our test runner. Tests should live next to the files that they cover. Check out Jest's docs for more details on writing Jest tests, and check out Go's testing docs for more details on testing Go code.

You need to install Node.js >= 12 and install jest by npm install jest to run the JS tests.

Working on the web UI

Hound includes a web UI that is composed of several files (html, css, javascript, etc.). To compile UI changes use:

make ui

To make development easier, there is a flag that will read the files from the file system (allowing the much-loved edit/refresh cycle).

First you should ensure you have all the dependencies installed that you need by running:

make dev

Then run the hound server with the --dev option:

.build/bin/houndd --dev

Get in Touch

Created at Etsy by:

• Kelly Norton
• Jonathan Klein

Hound is maintained by:

• David Schott
• Jacob Rose
• Nick Sawyer
• Salem Hilal
• Brad Greenlee
• Jeffery Swensen
• Ifeanyi Agu
• Joe Torraca
• Gabe Aguilar
• Greg Petroski