Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

https://github.com/josh-project/josh

Just One Single History
https://github.com/josh-project/josh

git monorepo scm workflow

Last synced: 17 days ago
JSON representation

Just One Single History

Lists

README 

        
![Just One Single History](/splash.png)



Combine the advantages of a monorepo with those of multirepo setups by leveraging a

fast, incremental, and reversible implementation of git history filtering.



`josh-proxy` can be integrated with any git host:



```

$ docker run \

    -p 8000:8000 \

    -e JOSH_REMOTE=https://github.com \

    -v josh-vol:/data/git \

    joshproject/josh-proxy:latest

```



See [Container options](https://josh-project.github.io/josh/reference/container.html) for full list of environment variables.



## Use cases



### Partial cloning 



Reduce scope and size of clones by treating subdirectories of the monorepo

as individual repositories.



```

$ git clone https://josh-project.dev/josh.git:/docs.git

```



The partial repo will act as a normal git repository but only contain the files

found in the subdirectory and only commits affecting those files.

The partial repo supports both fetch as well as push operation.



This helps not just to improve performance on the client due to having fewer files in

the tree,

it also enables collaboration on parts of the monorepo with other parties

utilizing git's normal distributed development features.

For example, this makes it easy to mirror just selected parts of your

repo to public github repositories or specific customers.



### Project composition / Workspaces



Simplify code sharing and dependency management. Beyond just subdirectories,

Josh supports filtering, re-mapping and composition of arbitrary virtual repositories

from the content found in the monorepo.



The mapping itself is also stored in the repository and therefore versioned alongside

the code.



    

        

            Central monorepo

            Project workspaces

            workspace.josh file

        

    

    

        

            Folders and files in central.git

            Folders and files in project1.git

            


dependencies = :/modules:[

    ::tools/

    ::library1/

]



        

        

            Folders and files in project2.git

            

libs/library1 = :/modules/library1


        

    



Workspaces act as normal git repos:



```

$ git clone http://josh/central.git:workspace=workspaces/project1.git

```



### Simplified CI/CD



With everything stored in one repo, CI/CD systems only need to look into one source for each particular

deliverable.

However, in traditional monorepo environments, dependency management is handled by the build system.

Build systems are usually tailored to specific languages and need their input already checked

out on the filesystem.

So the question:



> "What deliverables are affected by a given commit and need to be rebuilt?"



cannot be answered without cloning the entire repository and understanding how the languages

used handle dependencies.



In particular, when using C family languages, hidden dependencies on header files are easy to miss.

For this reason, limiting the visibility of files to the compiler by sandboxing is pretty much a requirement

for reproducible builds.



With Josh, each deliverable gets its own virtual git repository with dependencies declared in the `workspace.josh`

file. This means answering the above question becomes as simple as comparing commit ids.

Furthermore, due to the tree filtering, each build is guaranteed to be perfectly sandboxed

and only sees those parts of the monorepo that have actually been mapped.



This also means the deliverables to be re-built can be determined without cloning any repos like

typically necessary with normal build tools.



### GraphQL API



It is often desireable to access content stored in git without requiring a clone of the repository.

This is useful for CI/CD systems or web frontends, such as dashboards.



Josh exposes a GraphQL API for that purpose. For example, it can be used to find all workspaces currently

present in the tree:



```

query {

  rev(at:"refs/heads/master", filter:"::**/workspace.josh") {

    files { path }

  }

}

```



### Caching proxy



Even without using the more advanced features like partial cloning or workspaces,

`josh-proxy` can act as a cache to reduce traffic between locations or keep your CI from

performing many requests to the main git host.



## FAQ



See [here](https://josh-project.github.io/josh/faq.html)