CRANLIKE

High-performance R package server

Description

cranlike is a package server providing a simple API for storing R packages and hosting cran-like repositories.

Packages are stored in the repository of a particular user or organization, and the server automatically generates the required repository index files from the database. This allows R users to install packages from a particular author or organization using only the repo parameter in install.packages().

The implementation is designed to be fast and extensible, with the potential expose additional filters or services, and scale up to large repositories.

SYNOPSIS

The /api endpoint exposes a simple REST api to store R packages. Here <type> must be one of src, win or mac.

GET,POST,DELETE
  /api/<user>/<package>/<version>/<type>

The /repos endpoint exposes the CRAN-like directory structure and package index files for a given user. The R user can simply set the repos parameter in install.packages() or available.packages():

GET
  /repos/<user>/src/contrib
  /repos/<user>/bin/windows/contrib
  /repos/<user>/bin/macosx/contrib/

For example the R user would use:

available.packages("http://myserver.com/repos/jeroen")
install.packages("curl", repos = "http://myserver.com/repos/jeroen")

Running the server

The easiest way to start your a server is to clone the this and run docker compose:

docker-compose up

Alternatively if you locally have mongodb and nodejs installed you can use:

./run-local.sh

Debugging the database

All data is stored in two mongodb collections:

• The packages collection in cranlike stores description fields for each package, including an MD5sum field that has a unique hash of the file.
• The gridfs files collection stores the package blobs, where the primary _id is the md5 of the file.

We don't store raw files on disk. To read raw data from the db in R you can use mongolite package:

library(mongolite)
packages <- mongolite::mongo(db = 'cranlike', collection = 'packages',
  url = "mongodb://root:example@localhost")
packages$find()

To inspect the table with the files:

bucket <- mongolite::gridfs(db = 'cranlike', prefix = 'files',
  url = "mongodb://root:example@localhost")
bucket$find()