Pagination

The CRUDRouter is set up to automatically paginate your routes for you. You can use the skip and limit query parameters to paginate your results.

Skip: Using the skip (int) parameter, you can skip a certain number of items before returning the items you want.

Limit: Using the limit (int) parameter, the maximum number of items to be returned can be defined.

Setting a Maximum Pagination Limit

When creating a new CRUDRouter you are able to set the maximum amount of items that will be returned per page. To do this, use the paginate kwarg when creating a new CRUDRouter as shown in the example below.

CRUDRouter(
    schema=MyPydanticModel, 
    paginate=25
)

Above a new CRUDRouter is being created that will paginate items at 25 items per page.

Example

Shown below is an example usage of pagination; using skip and limit to paginate results from the backend. More information on how to skip and limit can be used with fastapi can be found here.

Python

import requests

requests.get('http://localhost:5000/potatoes' params={
    'skip': 50,
    'limit': 25
})

Bash

curl -X GET -G \
'http://localhost:5000/potatoes' \
-d skip=50 \
-d limit=25

In the example above, 25 items on the third page are being returned from our fictitious CRUDRouter endpoint. It is the third page because we specified a skip of 50 items while having a limit of 25 items per page. If we were to want items on the fourth page we would simply have to increase the skip to 75.

Validation

CRUDRouter will return HTTP Validation error, status code 422, if any of these conditions are met:

• The skip parameter is set to less than 0
• The limit parameter is set to less than 1
• The limit parameter is set to more than the maximum allowed number of records if a maximum is specified.

Shown below is a sample validation error. In the example, a negative value for the skip parameter was supplied.

{
  "detail": {
    "detail": [
      {
        "loc": ["query", "skip"],
        "msg": "skip query parameter must be greater or equal to zero",
        "type": "type_error.integer"
      }
    ]
  }
}