Offline Crates Repository Mirror (offline crates.io mirror)

This tool enables you to create an offline mirror of the crates repository.

The crate meta-data and crates themselves are downloaded and then hosted using a file server. Minor modifications to the end users local cargo configuration are required to point at the locally hosted repository.

Downloading crates files

To download a mirror of the default crates.io repository:

cargo run -p downloader -- --location ./files --git-repository ./git

This will clone the crate repository's git repo to ./git and download the files to ./files.

The following additional parameters can be used:

• --existing defines a list of files which already exist in the offline index and their sha256. The following command will create the list of files:

  find . -name "*.crate" | xargs sha256sum > existing.files

  This list can be generated from the offline store and moved to the online location, or the list of files can be tracked at the online location and each set of additional files added to the list of existing files.

  If the existing files list is given, any matching crates will not be downloaded.

• --search-path defines a local path to look for crate files, if found the file will be copied in to the specified file location. The file location should not be given as a search path, files existing in the file location will not be re-downloaded.

Offline git repo

In the offline environment Cargo needs to be directed to a git repository where additional configuration information will be retrieved.

A copy of the git repository used to download the crates files should be transferred to the offline environment, and the config.json file changed to reflect the offline addressing:

{
  "dl": "http://localhost:8000/api/v1/crates",
  "api": "http://localhost:8000"
}

This change must be committed to the default branch.

Offline file server

A simple offline file server implementing the crates API is required.

The server can be started using the following command:

cargo run -p server -- --location /mnt/crates --git-repository http://localhot:8080/crates.io-index.git

The following additional parameters can be used:

• --search-path will look for missing crate files and copy them in to the given file store

Local configuration

Cargo looks for its configuration in a number of locations. This includes the ./.cargo/config for each project and $HOME/.cargo/config for all of a users projects.

The following can be added to $HOME/.cargo/config files to configure which repository Cargo uses for its index:

[source]

[source.mirror]
registry = "http://localhost:8080/crates.io-index.git"

[source.crates-io]
replace-with = "mirror"