EDRDG Dictionary Archive Utils

Dictionary file versions are archived in the EDRDG Dictionary Archive as sequences of patches. The script in this repo allows for files to be easily rebuilt from those patches and for new patches to be written to the archive.

Usage: edrdg_dictionary_archive [OPTIONS] <command>

Commands
  get
      Build a specified file and print its path.

  update
      Get the latest file data from 'ftp.edrdg.org::nihongo',
      add the patches to the archive, and commit to Git.

General Options
  -h, --help
      Print this message.

  -v, --version
      Print the version of this script.

  -r, --repo-dir=<path>
      Path to the local edrdg-dictionary-archive Git repo.
      Default: '$XDG_DATA_HOME/Jitendex/edrdg-dictionary-archive'

  -i, --init
      Download the edrdg-dictionary-archive Git repo from
      https://github.com/Jitendex/edrdg-dictionary-archive
      if it doesn't already exist.

  -s, --verify-signature
      Verify GPG signature of latest git commit.

Options for the 'get' Command
  -f, --file=<file>
      Name of the file to get. Must be one of
        JMdict
        JMdict_b
        JMdict_e
        JMdict_e_examp
        JMdict_b_NG
        JMdict_e_NG
        JMdict_e_NG_examp
        JMnedict.xml
        kanjidic2.xml
        examples.utf

  -d, --date=YYYY-MM-DD
      Date of the file to get.

  -l, --latest
      Instead of specifying a date, use the most recent available.

Building a File

The get command builds a particular file for a particular date.

# Build JMdict from January 1, 2024
fish edrdg_dictionary_archive.fish get --file=JMdict --date=2024-01-01

# Build the latest available version of kanjidic2.xml
fish edrdg_dictionary_archive.fish get --file=kanjidic2.xml --latest

The resulting file is compressed and written to the user's cache directory (in $XDG_CACHE_HOME). The full path to the Brotli-compressed file is printed to stdout.

If an older version of the file is present in the user's cache, the script will use it as the base file for patching. For example, if a JMdict file for 2025-11-01 exists in the cache, then only one patch file will be applied to it to get the file for 2025-11-02. Otherwise, hundreds of patches would be applied to the repo's original base file (from 2023) to get to 2025.

Warning

Patching these large XML files is computationally expensive, and it may take several minutes to patch a base file from 2023 to the latest version. If the latest version of a file is all you need, you should get it from the EDRDG FTP server instead.

Updating the Archive

The update command builds the latest archived version of each file and compares them to the current versions of the files on the EDRDG FTP server. The diff of each file is written to the archive as a new patch.

The updated files are saved to the user's cache directory. Since this update is intended to be run daily, the previous versions of the files are removed from the cache.

# Usage example
fish edrdg_dictionary_archive.fish update

# Using a different data directory
fish edrdg_dictionary_archive update --repo-dir=/path/to/data/directory

Job Scheduling

A systemd service unit and timer are included for running this script daily. To push commits to GitHub without entering a password, a fine-grained personal access token (PAT) should be created and given "content" privileges for the relevant repo.

If git is configured to store credentials, it will save the PAT to ~/.git-credentials after the token is used for the first time.

git config credential.helper store

Dependencies

In addition to the the fish shell and the standard GNU coreutils (mkdir, cp, rm, date, etc.), these scripts also expect the following commands to be available.

• git
• rsync
• brotli
• patch
• diff
• cmp
• grep
• gpg

The PKGBUILD script for Arch Linux might serve as a useful example for packaging the files for other platforms.

License

Copyright (c) 2025-2026 Stephen Kraus

Licensed under the Apache License, Version 2.0 (the "License"); you may not use these files except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.