Part-DB.Part-DB-server/docs/api/intro.md

---
title: Introduction
layout: default
parent: API
nav_order: 1
---

# Introduction

Part-DB provides a [REST API](https://en.wikipedia.org/wiki/REST) to programmatically access the data stored in the database.
This allows external applications to interact with Part-DB, extend it or integrate it into other applications.

{: .warning }
> This feature is currently in beta. Please report any bugs you find.
> The API should not be considered stable yet and could change in future versions, without prior notice.
> Also be aware, that there might be security issues in the API, which could allow attackers to access or edit data via the API, which
> they normally should be able to access. So currently you should only use the API with trusted users and trusted applications.

Part-DB uses [API Platform](https://api-platform.com/) to provide the API, which allows for easy creation of REST APIs with Symfony and gives you a lot of features out of the box.
See the [API Platform documentation](https://api-platform.com/docs/core/) for more details about the API Platform features and how to use them.

## Enable the API

The API is available under the `/api` path, but not reachable without proper permissions.
You have to give the users, which should be able to access the API the proper permissions (Misceallaneous -> API).
Please note that there are two relevant permissions, the first one allows users to access the `/api/` path at all and showing the documentation,
and the second one allows them to create API tokens which is needed for authentication of external applications.
 
## Authentication

To use API endpoints, the external application has to authenticate itself, so that Part-DB knows which user is accessing the data and
which permisions the application should have. Basically this is done by creating a API token for a user and then passing it on every request 
with the `Authorization` header as bearer token, so you add a header `Authorization: Bearer <your token>`.

See [Authentication chapter]({% link api/authentication.md %}) for more details.

## API endpoints

The API is split into different endpoints, which are reachable under the `/api/` path of your Part-DB instance (so `https://your-part-db.local/api/`).
There are various endpoints for each entity type (like `part`, `manufacturer`, etc.), which allow you to read and write data and some special endpoints like `search` or `statistics`.

For example all API endpoints for managing categories are available under `/api/categories/`. Depending on the exact path and the HTTP method used, you can read, create, update or delete categories.
For most entities, there are endpoints like this:
* **GET**: `/api/categories/` - List all categories in the database (with pagination of the results)
* **POST**: `/api/categories/` - Create a new category
* **GET**: `/api/categories/{id}` - Get a specific category by its ID
* **DELETE**: `/api/categories/{id}` - Delete a specific category by its ID
* **UPDATE**: `/api/categories/{id}` - Update a specific category by its ID. Only the fields which are sent in the request are updated, all other fields are left unchanged. Be aware that you have to set the [JSON Patch](https://en.wikipedia.org/wiki/JSON_Patch) content type header (`Content-Type: application/merge-patch+json`) for this to work.

A full (interactive) list of endpoints can be displayed when visiting the `/api/` path in your browser, when you are logged in with a user, which is allowed to access the API.
There is also a link to this page, on the user settings page in the API token section.
This documentation also list all available fields for each entity type and the allowed operations.

## Formats

The API supports different formats for the request and response data, which you can control via the `Accept` and `Content-Type` headers.
You should use [JSON-LD](https://json-ld.org/) as format, which is basically JSON with some additional metadata, which allows 
to describe the data in a more structured way and also allows to link between different entities. You can achieve this by setting `Accept: application/ld+json` header to the API requests.

## OpenAPI schema

Part-DB provides a [OpenAPI](https://swagger.io/specification/) (formally Swagger) schema for the API under `/api/docs.json` (so `https://your-part-db.local/api/docs.json`).
This schema is a machine readable description of the API, which can be imported in software to test the API or even automatically generate client libraries for the API.

API generators which can generate a client library for the API from the schema are available for many programming languages, like [OpenAPI Generator](https://openapi-generator.tech/). 

## Interactive documentation

Part-DB provides an interactive documentation for the API, which is available under `/api/docs` (so `https://your-part-db.local/api/docs`).
You can pass your API token in the form on the top of the page, to authenticate yourself and then you can try out the API directly in the browser.
This is a great way to test the API and see how it works, without having to write any code.