Backend Interceptor

HTTP request processing component based on interceptor pattern, providing the ability to automatically execute business logic before and after request processing, supporting unified management of cross-cutting concerns such as permission verification, parameter validation, log recording, and exception handling.

The hierarchical structure of interceptor elements is Meta (interceptors.Meta) → Type (interceptors.Http) → Instance, supporting only full-code creation.

Quick Start

Creating Instance Elements

Directory Structure

Recommended Backend Interceptor Element Directory Structure

interceptors/
└── MyInterceptor/
    ├── e.json
    ├── __init__.py
    ├── interceptor.py
    └── handler.py (optional)

e.json File

Backend Interceptor e.json Example

{
  "title": "Custom Interceptor",
  "type": "interceptors.Http",
  "backendBundleEntry": ".",
  "icon": "lanjieqi1",
  "sort": 100
}

Business Logic Code

interceptor.py Implementation

from interceptors.Http import RequestInterceptor
from jit.commons.utils.logger import log

class MyInterceptor(RequestInterceptor):
    def before(self):
        """Execute before request processing"""
        log.info(f"Request started: {self.request.path}")

    def after(self, resData=None):
        """Execute after request processing"""
        log.info(f"Request ended: {self.request.path}")

    def onSuccess(self, resData=None):
        """Execute when request processing succeeds"""
        log.info("Request processing successful")

    def onException(self, exc=None):
        """Execute when request processing exception occurs"""
        log.error(f"Request processing exception: {exc}")
        return exc

Methods

before

Method executed before request processing, used for parameter validation, permission checking, and other preprocessing logic.

after

Method executed after request processing, executed regardless of success or failure, used for resource cleanup, log recording, and other post-processing logic.

onSuccess

Method executed when request processing succeeds, only called when there are no exceptions.

onException

Method executed when request processing exception occurs, used for exception handling and log recording.

Properties

request

Current HTTP request object, containing request path, parameters, headers, etc.

functionDefine

Function definition information corresponding to current request, obtained by parsing request path to get target element's function metadata.

Advanced Features

Execution Order

Control interceptor execution order through sort field in e.json.

Set Execution Order

{
  "title": "High Priority Interceptor",
  "type": "interceptors.Http",
  "sort": 10
}

When multiple interceptors exist:

• When request arrives, execute before in ascending sort order
• When request ends, execute onException, onSuccess in ascending sort order
• When request ends, execute after in descending sort order

Platform Built-in Interceptors

Login status interceptor (interceptors.Auths sort=1): When loginRequired=false is configured for a function in e.json's functionList, login status verification for that function will be ignored.

API request log recording (interceptors.Logger sort=9980)

User role permission verification (interceptors.Permission sort=999)

Request signature verification (interceptors.Sign sort=100): When ignoreSign=true is configured for a function in e.json's functionList, signature verification for that function will be ignored.

XML request body to Dict conversion (interceptors.XmlParse sort=999)