949fdc4784
Summary: introduce augmented manifests types (storage layer). Background: **Augmented Manifest** is our new data structure represented familiar tree manifest with **two** pointers: traditional mercurial hgid and a newly introduced content-addressed blake3 pointer that would be a hash of child entry serialised with a **custom serialisation format**. We also include size of that serialised blob to form a Digest compatible with CAS. The new data structure will allow storing Source Control data in CAS, and provide efficient way for Eden to fetch AUX data together with trees, replacing the current slow and inefficient implementation, that triggers fetching lots of blobs (per leaf file entry). The new format also supports sharing from the beginning, that is important for Mononoke performance for large manifests. The HgAugmentedManifestEnvelope is the type internal to Mononoke for storing. Reviewed By: markbt Differential Revision: D55635473 fbshipit-source-id: 39d2adf1874512d3ed42b0e6d2e1cb785246b493 |
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.devcontainer | ||
.github/workflows | ||
addons | ||
build | ||
ci | ||
CMake | ||
common | ||
configerator/structs/scm | ||
eden | ||
fb303/thrift | ||
thrift/annotation | ||
website | ||
.gitignore | ||
.projectid | ||
build.bat | ||
build.sh | ||
clippy.toml | ||
CMakeLists.txt | ||
CODE_OF_CONDUCT.md | ||
CONTRIBUTING.md | ||
dependabot.yml | ||
LICENSE | ||
make-client.py | ||
README.md | ||
requirements_ubuntu.txt | ||
rustfmt.toml | ||
SAPLING_VERSION |
Sapling SCM
Sapling SCM is a cross-platform, highly scalable, Git-compatible source control system.
It aims to provide both user-friendly and powerful interfaces for users, as well as extreme scalability to deal with repositories containing many millions of files and many millions of commits.
Using Sapling
To start using Sapling, see the Getting Started page for how to clone your existing Git repositories. Checkout the Overview for a peek at the various features. Coming from Git? Checkout the Git Cheat Sheet.
Sapling also comes with an Interactive Smartlog (ISL) web UI for seeing and interacting with your repository, as well as a VS Code integrated Interactive Smartlog.
The Sapling Ecosystem
Sapling SCM is comprised of three main components:
- The Sapling client: The client-side
sl
command line and web interface for users to interact with Sapling SCM. - Mononoke: A highly scalable distributed source control server. (Not yet supported publicly.)
- EdenFS: A virtual filesystem for efficiently checking out large repositories. (Not yet supported publicly.)
Sapling SCM's scalability goals are to ensure that all source control operations scale with the number of files in use by a developer, and not with the size of the repository itself. This enables fast, performant developer experiences even in massive repositories with millions of files and extremely long commit histories.
Sapling CLI
The Sapling CLI, sl
, was originally based on
Mercurial, and shares various aspects of the UI
and features of Mercurial.
The CLI code can be found in the eden/scm
subdirectory.
Mononoke
Mononoke is the server-side component of Sapling SCM.
While it is used in production within Meta, it currently does not build in an open source context and is not yet supported for external usage.
EdenFS
EdenFS is a virtual file system for managing Sapling checkouts.
While it is used in production within Meta, it currently does not build in an open source context and is not yet supported for external usage.
EdenFS speeds up operations in large repositories by only populating working
directory files on demand, as they are accessed. This makes operations like
checkout
much faster, in exchange for a small performance hit when first
accessing new files. This is quite beneficial in large repositories where
developers often only work with a small subset of the repository at a time.
More detailed EdenFS design documentation can be found at eden/fs/docs/Overview.md.
Building the Sapling CLI
The Sapling CLI currently builds and runs on Linux, Mac, and Windows. It can be
built by running make oss
in the eden/scm
directory and running the
resulting sl
executable.
Building the Sapling CLI requires Python 3.8, Rust, CMake, and OpenSSL for the main cli, and Node and Yarn for the ISL web UI.
License
See LICENSE.