package ppx_irmin
Install
Dune Dependency
Authors
Maintainers
Sources
sha256=fac7c032f472fb369378ad2d8fe77e7cd3b3c1c6a0d7bf59980b69528891b399
sha512=06db1c4e90d43bdfbea2d4f15037eef77207877c05019a6ce0f7f7771afe7d9200da019e3d845ff98ee86947f3e538e1521d818e6d6ddd97105fcaeb746fe418
README.md.html
Irmin - A distributed database built on the same principles as Git
Irmin is an OCaml library for building mergeable, branchable distributed data stores.
Features
Built-in snapshotting - backup and restore
Storage agnostic - you can use Irmin on top of your own storage layer
Custom datatypes - (de)serialization for custom data types, derivable via
ppx_irmin
Highly portable - runs anywhere from Linux to web browsers and Xen unikernels
Git compatibility -
irmin-git
uses an on-disk format that can be inspected and modified using GitDynamic behavior - allows the users to define custom merge functions, use in-memory transactions (to keep track of reads as well as writes) and to define event-driven workflows using a notification mechanism
Documentation
Documentation can be found online at https://mirage.github.io/irmin
Installation
Prerequisites:
Please ensure to install the minimum Opam and Ocaml versions which are 2 and 4.07 respectively.
opam list // listing the installed packages
To install Irmin, the command-line tool and all optional dependencies using opam:
opam install irmin-unix
Note : If you face installation issues due to pinned packages. Run the below commands to unpin and try to install again,
Unpinning irmin-unix package,
opam info irmin-unix // to get available versions
opam pin -s | grep irmin | xargs opam unpin
A minimal installation, containing the reference in-memory backend, can be installed by running:
opam install irmin
The following packages have been made available on opam
:
irmin
- the base package, plus an in-memory storage implementationirmin-chunk
- chunked storageirmin-fs
- filesystem-based storage usingbin_prot
irmin-git
- Git compatible storageirmin-graphql
- GraphQL serverirmin-http
- a simple REST interfaceirmin-mirage
- mirage compatibilityirmin-mirage-git
- Git compatible storage for mirageirmin-mirage-graphql
- mirage compatible GraphQL serverirmin-unix
- unix compatibilityirmin-pack
- compressed, on-disk, posix backendppx_irmin
- PPX deriver for Irmin content types (see README_PPX.md)irmin-containers
- collection of simple, ready-to-use mergeable data structures
For more information about an individual package consult the online documentation.
Development version
To install the development version of Irmin, clone this repository and opam install
the packages inside:
git clone https://github.com/mirage/irmin
cd irmin/
opam install .
Examples
Below is a simple example of setting a key and getting the value out of a Git based, filesystem-backed store.
open Lwt.Syntax
(* Irmin store with string contents *)
module Store = Irmin_unix.Git.FS.KV(Irmin.Contents.String)
(* Database configuration *)
let config = Irmin_git.config ~bare:true "/tmp/irmin/test"
(* Commit author *)
let author = "Example <example@example.com>"
(* Commit information *)
let info fmt = Irmin_unix.info ~author fmt
let main =
(* Open the repo *)
let* repo = Store.Repo.v config in
(* Load the master branch *)
let* t = Store.master repo in
(* Set key "foo/bar" to "testing 123" *)
let* () =
Store.set_exn t ~info:(info "Updating foo/bar") ["foo"; "bar"]
"testing 123"
in
(* Get key "foo/bar" and print it to stdout *)
let+ x = Store.get t ["foo"; "bar"] in
Printf.printf "foo/bar => '%s'\n" x
(* Run the program *)
let () = Lwt_main.run main
The example is contained in examples/readme.ml
. It can be compiled and executed with dune:
$ dune build examples/readme.exe
$ dune exec examples/readme.exe
foo/bar => 'testing 123'
The examples/
directory also contains more advanced examples, which can be executed in the same way.
Command-line
The same thing can also be accomplished using irmin
, the command-line application installed with irmin-unix
, by running:
$ echo "root: ." > irmin.yml
$ irmin init
$ irmin set foo/bar "testing 123"
$ irmin get foo/bar
irmin.yml
allows for irmin
flags to be set on a per-directory basis. You can also set flags globally using $HOME/.irmin/config.yml
. Run irmin help irmin.yml
for further details.
Also see irmin --help
for list of all commands and either irmin <command> --help
or irmin help <command>
for more help with a specific command.
Issues
Feel free to to report any issues using the Github bugtracker.
Conditions
See the LICENSE file.
Acknowledgements
Development of Irmin was supported in part by the EU FP7 User-Centric Networking project, Grant No. 611001.