fastapi-voyager 0.4.2

Visualize FastAPI application's routing tree and dependencies

This repo is still in early stage, currently it supports pydantic v2 only, previous name: fastapi-router-viz

Inspect your API interactively

Installation

pip install fastapi-voyager
# or
uv add fastapi-voyager

Dependencies

• FastAPI
• pydantic-resolve

Feature

For scenarios of using FastAPI as internal API integration endpoints, fastapi-voyager helps to visualize the dependencies.

It is also an architecture inspection tool that can identify issues in data relationships through visualization during the design phase.

If the process of building the view model follows the ER model, the full potential of fastapi-voyager can be realized. It allows for quick identification of APIs that use entities, as well as which entities are used by a specific API

git clone https://github.com/allmonday/fastapi-voyager.git
cd fastapi-voyager

voyager -m tests.demo 
           --server --port=8001 
           --module_color=tests.service:blue 
           --module_color=tests.demo:tomato

generate the graph

after initialization, pick tag, rotue (optional) and click generate.

highlight

click a node to highlight it's upperstream and downstream nodes. figure out the related models of one page, or homw many pages are related with one model.

filter related nodes

shift click a node to check related node, pick a field to narrow the result.

view source code

alt click a node to show source code or open file in vscode.

alt click a route to show source code or open file in vscode

Command Line Usage

open in browser

# open in browser
voyager -m tests.demo --server  

voyager -m tests.demo --server --port=8002

generate the dot file

# generate .dot file
voyager -m tests.demo  

voyager -m tests.demo --app my_app

voyager -m tests.demo --schema Task

voyager -m tests.demo --show_fields all

voyager -m tests.demo --module_color=tests.demo:red --module_color=tests.service:tomato

voyager -m tests.demo -o my_visualization.dot

voyager --version

The tool will generate a DOT file that you can render using Graphviz:

# Install graphviz
brew install graphviz  # macOS
apt-get install graphviz  # Ubuntu/Debian

# Render the graph
dot -Tpng router_viz.dot -o router_viz.png

# Or view online at: https://dreampuf.github.io/GraphvizOnline/

or you can open router_viz.dot with vscode extension graphviz interactive preview

Plan

features:

• group schemas by module hierarchy
• module-based coloring via Analytics(module_color={...})
• view in web browser
  • config params
  • make a explorer dashboard, provide list of routes, schemas, to make it easy to switch and search
• support programmatic usage
• better schema /router node appearance
• hide fields duplicated with parent's (show parent fields instead)
• refactor the frontend to vue, and tweak the build process
• find dependency based on picked schema and it's field.
• optimize static resource (cdn -> local)
• add configuration for highlight (optional)
• alt+click to show field details
• display source code of routes (including response_model)
• handle excluded field
• user can generate nodes/edges manually and connect to generated ones
• support dataclass
• group routes by module hierarchy
• integration with pydantic-resolve
  • show difference between resolve, post fields
  • strikethrough for excluded fields
  • display loader as edges
• test cases

bugs:

• fix duplicated link from class and parent class, it also break clicking highlight

Credits

• https://apis.guru/graphql-voyager/, for inspiration.
• https://github.com/tintinweb/vscode-interactive-graphviz, for web visualization.