Metadata-Version: 2.5
Name: fromscratch-pygraphdb
Version: 0.4.0
Summary: An educational graph database library built from scratch in Python
Project-URL: Homepage, https://github.com/robcox2910/pygraphdb
Project-URL: Repository, https://github.com/robcox2910/pygraphdb
Project-URL: Issues, https://github.com/robcox2910/pygraphdb/issues
Project-URL: Documentation, https://robcox2910.github.io/pygraphdb/
Author: Rob Cox
License: MIT
License-File: LICENSE
Keywords: database,education,graph,neo4j
Classifier: Development Status :: 3 - Alpha
Classifier: Intended Audience :: Education
Classifier: License :: OSI Approved :: MIT License
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.14
Classifier: Topic :: Education
Classifier: Topic :: Software Development :: Libraries
Classifier: Typing :: Typed
Requires-Python: >=3.14
Provides-Extra: dev
Requires-Dist: commitizen>=4.4.0; extra == 'dev'
Requires-Dist: hypothesis>=6.170; extra == 'dev'
Requires-Dist: pip-audit>=2.10.0; extra == 'dev'
Requires-Dist: pre-commit>=4.0.1; extra == 'dev'
Requires-Dist: pyright>=1.1.400; extra == 'dev'
Requires-Dist: pytest-cov>=6.0.0; extra == 'dev'
Requires-Dist: pytest>=8.3.4; extra == 'dev'
Requires-Dist: ruff>=0.9.3; extra == 'dev'
Description-Content-Type: text/markdown

# PyGraphDB

An educational graph database library built from scratch in Python. Part of the **PyLearn** educational platform for kids aged 12+.

A graph database stores data as **nodes** (entities) and **edges** (relationships) -- like a social network map where people are dots and friendships are lines connecting them.

## Features

- **Nodes & Edges** -- Create entities with labels and properties, connect them with typed relationships
- **CRUD Operations** -- Add, get, update, and delete nodes and edges
- **Graph Traversal** -- Explore your graph with BFS (breadth-first) and DFS (depth-first) algorithms
- **Shortest Path** -- Find the quickest route between two nodes (like GPS directions)
- **Pattern Matching** -- Search for nodes and edges by label, type, or properties
- **Cypher-like Queries** -- Ask questions with a simple query language inspired by Neo4j's Cypher
- **Persistence** -- Save and load your graph to/from JSON files
- **Neighbor & Degree** -- Find connected nodes and count connections

## Quick Start

```python
from pygraphdb import Graph, bfs, shortest_path, execute_query, find_nodes

# Create a social network
g = Graph()
g.add_node("alice", label="Person", properties={"name": "Alice", "age": 13})
g.add_node("bob", label="Person", properties={"name": "Bob", "age": 14})
g.add_node("charlie", label="Person", properties={"name": "Charlie", "age": 13})

g.add_edge("e1", "alice", "bob", rel_type="KNOWS")
g.add_edge("e2", "bob", "charlie", rel_type="KNOWS")

# Find Alice's friends
friends = g.get_neighbors("alice", direction="outgoing")
print([f.properties["name"] for f in friends])  # ['Bob']

# Traverse the whole network
visited = bfs(g, "alice")
print([n.properties["name"] for n in visited])  # ['Alice', 'Bob', 'Charlie']

# Find shortest path
path = shortest_path(g, "alice", "charlie")
print([n.properties["name"] for n in path])  # ['Alice', 'Bob', 'Charlie']

# Query with Cypher-like syntax
results = execute_query(g, 'MATCH (n:Person) WHERE n.name = "Alice" RETURN n')
print(results[0].properties["name"])  # 'Alice'

# Pattern matching
teenagers = find_nodes(g, label="Person")
print(len(teenagers))  # 3
```

## Installation

```bash
# Clone and install
git clone https://github.com/robcox2910/pygraphdb.git
cd pygraphdb
uv sync --all-extras

# Run tests
uv run pytest

# Lint & type check
uv run ruff check src/ tests/
uv run pyright src tests
```

## Releasing

Other projects in the series ([PyStack](https://github.com/robcox2910/pystack)) use a pinned release of this one,
not whatever is on `main`. To publish a change for them:

1. Merge the change to `main`.
2. Tag it: `git tag -a vX.Y.Z -m vX.Y.Z && git push origin vX.Y.Z`.
   A change to the public API bumps the minor version (`v0.1.0` → `v0.2.0`);
   anything else bumps the patch (`v0.1.0` → `v0.1.1`).
3. In each project that uses it, edit the tag in `[tool.uv.sources]`, run
   `uv lock --upgrade-package <name>`, and open a pull request so CI checks
   the pair together.

<!-- series:start -->
## Related Projects

This project is one of a series that builds real systems "from scratch in Python" to teach how they work. See the [series home](https://robcox2910.github.io/) for the full story.

| Project | What it teaches | Repository | Docs |
| --- | --- | --- | --- |
| PyOS | Operating systems | [py-os](https://github.com/robcox2910/py-os) | [Docs](https://robcox2910.github.io/py-os/) |
| Pebble | Compilers and programming languages | [pebble-lang](https://github.com/robcox2910/pebble-lang) | [Docs](https://robcox2910.github.io/pebble-lang/) |
| PyDB | Relational databases | [pydb](https://github.com/robcox2910/pydb) | [Docs](https://robcox2910.github.io/pydb/) |
| PyKV | Key-value stores | [pykv](https://github.com/robcox2910/pykv) | [Docs](https://robcox2910.github.io/pykv/) |
| PyDocDB | Document databases | [pydoc-db](https://github.com/robcox2910/pydoc-db) | [Docs](https://robcox2910.github.io/pydoc-db/) |
| **PyGraphDB** | **Graph databases** | [pygraphdb](https://github.com/robcox2910/pygraphdb) | [Docs](https://robcox2910.github.io/pygraphdb/) |
| PyTSDB | Time-series databases | [pytsdb](https://github.com/robcox2910/pytsdb) | [Docs](https://robcox2910.github.io/pytsdb/) |
| PyVecDB | Vector databases | [pyvecdb](https://github.com/robcox2910/pyvecdb) | [Docs](https://robcox2910.github.io/pyvecdb/) |
| PyColDB | Column-family databases | [pycoldb](https://github.com/robcox2910/pycoldb) | [Docs](https://robcox2910.github.io/pycoldb/) |
| PyCrypt | Cryptography | [pycrypt](https://github.com/robcox2910/pycrypt) | [Docs](https://robcox2910.github.io/pycrypt/) |
| PyNet | Computer networking | [pynet](https://github.com/robcox2910/pynet) | [Docs](https://robcox2910.github.io/pynet/) |
| PyWeb | HTTP web servers | [pyweb](https://github.com/robcox2910/pyweb) | [Docs](https://robcox2910.github.io/pyweb/) |
| PyGit | Version control | [pygit](https://github.com/robcox2910/pygit) | [Docs](https://robcox2910.github.io/pygit/) |
| PySearch | Search engines | [pysearch](https://github.com/robcox2910/pysearch) | [Docs](https://robcox2910.github.io/pysearch/) |
| PyMQ | Message queues | [pymq](https://github.com/robcox2910/pymq) | [Docs](https://robcox2910.github.io/pymq/) |
| PyLLM | Language models (the brain) | [pyllm](https://github.com/robcox2910/pyllm) | [Docs](https://robcox2910.github.io/pyllm/) |
| PyScheduler | Job scheduling | [pyscheduler](https://github.com/robcox2910/pyscheduler) | [Docs](https://robcox2910.github.io/pyscheduler/) |
| PyStack | Full-stack integration | [pystack](https://github.com/robcox2910/pystack) | [Docs](https://robcox2910.github.io/pystack/) |
<!-- series:end -->

<!-- docs:start -->
## Documentation

Full docs (with kid-friendly explanations of every idea): https://robcox2910.github.io/pygraphdb/
<!-- docs:end -->
