ChronoGraph

Github, but for graphs!

A temporal, versioned graph library in C++17 with Git-like branching & merging, time-travel snapshots, diffs, and graph algorithms.

Chronograph can be used for social-network evolution, financial audit trails, collaborative knowledge-graph editing, and more. Python support is provided via PyBind11.

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Features

• Event Sourcing
  Full history of node/edge additions, deletions, and updates with timestamps

• Snapshots & Time-Travel
  View the graph at a certain point in time and run any algorithm on it, or replay the graph changes between two points in time

• Temporal Queries
  Per-node and per-edge history, point-in-time lookups, and time-window queries over the event log

• Diffing
  Compute added/removed/updated nodes and edges between two points in time, two snapshots, or two branches/commits

• Repository & Commits
  ChronoGraph provides a Respository object at the top level. Changes to the graph are committed and stored as Commit objects

• Branching & Merging
  Graph repositories support branching, fast-forward and three-way merges with per-attribute conflict detection, automatic merge policies, and interactive conflict resolution

• Saving & Loading
  Save graphs and whole repositories (including uncommitted work) to versioned, diff-friendly JSON

• Graph Algorithms
  Reachability, shortest paths, connected components, topological sorting, cycle detection, and more are offered in a dedicated graph/algorithms/ submodule

Prerequisites

You need:

• CMake 3.14 or later
• A C++17-capable compiler (e.g. GCC 7+, Clang 5+)
• GoogleTest (or internet access: by default, GTest is fetched by CMake's FetchContent)
• For using ChronoGraph in python, see additional requirements in binding documentation

Getting Started

# 1) Clone the repo
git clone https://github.com/jun-simons/ChronoGraph.git
cd ChronoGraph

# 2) Create a build directory
mkdir build && cd build

# 3) Configure & build
cmake ..
make -j$(nproc)            # or `cmake --build . -- -j4` on some platforms

# 4) (Optional) Run the unit tests
ctest --output-on-failure -V

# 5) (Optional) Run the example code
./examples/example_repo

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Basic Usage: Graph

#include <chronograph/graph/Graph.h>
#include <chronograph/graph/Snapshot.h>

using namespace chronograph;

Graph g;
g.addNode("n1", {{"name","Alice"}}, timestamp);
g.addNode("n2", {{"name","Bob"}}, timestamp);
g.addEdge("e1","n1","n2",{},timestamp);

Snapshot snap(g, someTimestamp);
auto nodes = snap.getNodes();

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Basic Usage: Reachability

#include <chronograph/graph/algorithms/Paths.h>

using chronograph::graph::algorithms::isReachable;

bool canReach = isReachable(g, "A", "B");

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Basic Usage: Repository (Commits & Branches)

#include <chronograph/repo/Repository.h>

auto repo = Repository::init("main");
repo.addNode("A", {...}, ts);
auto c1 = repo.commit("add A");

repo.branch("dev");
repo.checkout("dev");
repo.addNode("B", {...}, ts);
auto c2 = repo.commit("add B");

repo.checkout("main");
auto result = repo.merge("dev", MergePolicy::OURS);

Documentation

For in-depth design and API details, see the docs/ folder.

License

MIT © Jun Simons

This project is in early development (www.junsimons.com)