类似于 main.py 的 Django 应用程序的入口点是什么？ 在哪里设置参数？

Question

我想设置一些参数并初始化 Injector object，因为我想在我的 Django 应用程序中使用依赖注入和单例。

通常我在我的应用程序的 main.py 中执行此操作，但是使用 Django 我看不到应用程序运行时的第一个入口点在哪里。 我应该在哪里初始化注入器并将我的视图和服务传递给它？

我有这样的看法：

from uuid import UUID
from django.shortcuts import render
from django.http.response import JsonResponse
from django.http.request import HttpRequest
from rest_framework import viewsets, status
from rest_framework.parsers import JSONParser
from rest_framework.response import Response
from Instruments.services import InstrumentsService
from rest_framework.decorators import api_view
from Instruments.services import InstrumentsService
from injector import singleton, inject


# Application views live here
@singleton
class InstrumentViewSet(viewsets.ModelViewSet):
    @inject
    def __init__(self, instrument_service: InstrumentsService, **kwargs):
        self.instrument_service = instrument_service
        super().__init__(**kwargs)

    def list(self, request: HttpRequest):
        data = {}

        try:
            data = self.instrument_service.get_instruments()
            return JsonResponse(data, status=status.HTTP_200_OK, safe=False)
        except Exception as exc:
            return JsonResponse(
                {"Status": f"Error: {exc}"},
                status=status.HTTP_400_BAD_REQUEST,
                safe=False,
            )

    def create(self, request):
        instrument_data = JSONParser().parse(request)
        data = {}

        try:
            data = self.instrument_service.add_instrument(instrument_data)
            return JsonResponse(data, status=status.HTTP_201_CREATED, safe=False)
        except Exception as exc:
            return JsonResponse(data, status=status.HTTP_400_BAD_REQUEST, safe=False)

    def retrieve(self, request, pk: UUID = None):
        data = {}

        try:
            data = self.instrument_service.get_instrument_by_id(pk)
            return JsonResponse(data, status=status.HTTP_200_OK, safe=False)
        except Exception as exc:
            return JsonResponse(
                {"Status": f"Error: {exc}"},
                status=status.HTTP_404_NOT_FOUND,
                safe=False,
            )

    def update(self, request, pk: UUID = None):
        instrument_data = JSONParser().parse(request)
        data = {}

        try:
            data = self.instrument_service.update_instrument_by_id(pk, instrument_data)
            return JsonResponse(data, status=status.HTTP_200_OK, safe=False)
        except Exception as exc:
            return JsonResponse(
                {"Status": f"Error: {exc}"},
                status=status.HTTP_404_NOT_FOUND,
                safe=False,
            )

    def destroy(self, request, pk: UUID = None):
        data = {}
        try:
            data = self.instrument_service.delete_instrument_by_id(pk)
            return JsonResponse(data, status=status.HTTP_200_OK, safe=False)
        except Exception as exc:
            return JsonResponse(
                {"Status": f"Error: {exc}"},
                status=status.HTTP_404_NOT_FOUND,
                safe=False,
            )

和这样的服务：

import uuid
from django.http.response import JsonResponse
from django.http.request import RAISE_ERROR, HttpRequest
from rest_framework.exceptions import NotFound, ValidationError
from rest_framework.parsers import JSONParser
from rest_framework import status
from Instruments.models import Instrument
from Instruments.serializers import InstrumentsSerializer
from django.shortcuts import get_object_or_404
from injector import inject, singleton


@singleton
class InstrumentsService:
    @inject
    def __init__(self, instruments: Instrument):
        self.instruments = instruments.objects.all()

    def get_instrument_by_id(self, id: uuid.UUID):
        try:
            instruments = get_object_or_404(self.instruments, pk=id)
            serializer = InstrumentsSerializer(instruments)

        except Instrument.DoesNotExist as exc:
            raise NotFound(f"No items where found with the given id {id}")

        return serializer.data

    def update_instrument_by_id(self, id: uuid.UUID, instrument_data: dict):
        try:

            instruments = get_object_or_404(self.instruments, pk=id)
            serializer = InstrumentsSerializer(instruments, data=instrument_data)

            if serializer.is_valid():
                serializer.save()

            else:
                raise ValidationError(
                    "The data provided for updating an instrument are not valid"
                )

        except Instrument.DoesNotExist as exc:
            raise NotFound(f"No items where found with the given id {id}")

        self.instruments = Instrument.objects.all()
        return serializer.data

    def delete_instrument_by_id(self, id: uuid.UUID):
        try:

            instruments = get_object_or_404(self.instruments, pk=id)
            serializer = InstrumentsSerializer(instruments)
            instruments.delete()

        except Instrument.DoesNotExist as exc:
            raise NotFound(f"No items where found with the given id {id}")

        self.instruments = Instrument.objects.all()
        return serializer.data

    def get_instruments(self):
        serializer = InstrumentsSerializer(self.instruments, many=True)

        return serializer.data

    def add_instrument(self, instrument_data: Instrument):

        serializer = InstrumentsSerializer(data=instrument_data)

        if serializer.is_valid():
            serializer.save()
        else:
            raise ValidationError(
                "The data provided for registering a new instrument are not valid"
            )

        self.instruments = Instrument.objects.all()
        return serializer.data

有人会在哪里初始化注入器以创建依赖项？

Answer 1

也许你可以看看Django Applications

在您的应用程序文件夹中，您可能有一个apps.py文件：

from django.apps import AppConfig

class MyApp(AppConfig):

    def ready(self):
        # do stuff here

这是您的应用程序的入口点。

编辑：

有一个项目已经这样做了： django-injector

Answer 2

好的，我使依赖注入工作，问题不是注入器，而是在class InstrumentsService:中发布的事实：上面我试图做：

def __init__(self, instruments: Instrument):
    self.instruments = instruments.objects.all()

但是 object 管理器无法访问 Django object thourgh 对象（类实例），而是直接通过 ZA2F2221ED4F8EBC2CBB4 所以如果我更正class InstrumentsService:到这个并使用这个django-injector模块Django 注射器一切正常：

import uuid
from django.http.response import JsonResponse
from django.http.request import RAISE_ERROR, HttpRequest
from rest_framework.exceptions import NotFound, ValidationError
from rest_framework.parsers import JSONParser
from rest_framework import status
from Instruments.models import Instrument
from Instruments.serializers import InstrumentsSerializer
from django.shortcuts import get_object_or_404


class InstrumentsService:
    def __init__(self):
        self.instruments = Instrument.objects.all()

    def get_instrument_by_id(self, id: uuid.UUID):
        try:
            instruments = get_object_or_404(self.instruments, pk=id)
            serializer = InstrumentsSerializer(instruments)

        except Instrument.DoesNotExist as exc:
            raise NotFound(f"No items where found with the given id {id}")

        return serializer.data

    def update_instrument_by_id(self, id: uuid.UUID, instrument_data: dict):
        try:

            instruments = get_object_or_404(self.instruments, pk=id)
            serializer = InstrumentsSerializer(instruments, data=instrument_data)

            if serializer.is_valid():
                serializer.save()

            else:
                raise ValidationError(
                    "The data provided for updating an instrument are not valid"
                )

        except Instrument.DoesNotExist as exc:
            raise NotFound(f"No items where found with the given id {id}")

        self.instruments = Instrument.objects.all()
        return serializer.data

    def delete_instrument_by_id(self, id: uuid.UUID):
        try:

            instruments = get_object_or_404(self.instruments, pk=id)
            serializer = InstrumentsSerializer(instruments)
            instruments.delete()

        except Instrument.DoesNotExist as exc:
            raise NotFound(f"No items where found with the given id {id}")

        self.instruments = Instrument.objects.all()
        return serializer.data

    def get_instruments(self):
        serializer = InstrumentsSerializer(self.instruments, many=True)

        return serializer.data

    def add_instrument(self, instrument_data: Instrument):

        serializer = InstrumentsSerializer(data=instrument_data)

        if serializer.is_valid():
            serializer.save()
        else:
            raise ValidationError(
                "The data provided for registering a new instrument are not valid"
            )

        self.instruments = Instrument.objects.all()
        return serializer.data