apollo-upload-client 和 graphene-django

Question

我对使用apollo-upload-client 和graphene-django 有疑问。 Here 我发现 apollo-upload-client 将 operations 添加到 formData。但是heregraphene-django 只是试图获取query 参数。问题是，应该在哪里以及如何修复它？

Answer 1

如果您指的是具有类似标题的数据（从 Chrome 工具查看 HTTP 时）：

Content-Disposition: form-data; name="operations"

和类似的数据

{"operationName":"MyMutation","variables":{"myData"....}, "query":"mutation MyMutation"...},

graphene-python 库对此进行解释并将其组装成一个查询，插入变量并从查询中删除文件数据。如果您使用的是 Django，则在编写突变时可以在info.context.FILES 中找到所有上传的文件。

Answer 2

这是我支持最新 apollo-upload-client (8.1) 的解决方案。当我从 apollo-upload-client 5.x 升级到 8.x 时，我最近不得不重新访问我的 Django 代码。希望这会有所帮助。

抱歉，我使用的是较旧的 graphene-django，但希望您可以将突变语法更新到最新版本。

上传标量类型（基本上是直通）：

class Upload(Scalar):
    '''A file upload'''

    @staticmethod
    def serialize(value):
        raise Exception('File upload cannot be serialized')

    @staticmethod
    def parse_literal(node):
        raise Exception('No such thing as a file upload literal')

    @staticmethod
    def parse_value(value):
        return value

我的上传突变：

class UploadImage(relay.ClientIDMutation):
    class Input:
        image = graphene.Field(Upload, required=True)

    success = graphene.Field(graphene.Boolean)

    @classmethod
    def mutate_and_get_payload(cls, input, context, info):
        with NamedTemporaryFile(delete=False) as tmp:
            for chunk in input['image'].chunks():
                tmp.write(chunk)
            image_file = tmp.name
        # do something with image_file
        return UploadImage(success=True)

繁重的工作发生在自定义 GraphQL 视图中。基本上它将文件对象注入到变量映射中的适当位置。

def maybe_int(s):
    try:
        return int(s)
    except ValueError:
        return s

class CustomGraphqlView(GraphQLView):
    def parse_request_json(self, json_string):
        try:
            request_json = json.loads(json_string)
            if self.batch:
                assert isinstance(request_json,
                                  list), ('Batch requests should receive a list, but received {}.').format(
                                      repr(request_json))
                assert len(request_json) > 0, ('Received an empty list in the batch request.')
            else:
                assert isinstance(request_json, dict), ('The received data is not a valid JSON query.')
            return request_json
        except AssertionError as e:
            raise HttpError(HttpResponseBadRequest(str(e)))
        except BaseException:
            logger.exception('Invalid JSON')
            raise HttpError(HttpResponseBadRequest('POST body sent invalid JSON.'))

    def parse_body(self, request):
        content_type = self.get_content_type(request)

        if content_type == 'application/graphql':
            return {'query': request.body.decode()}

        elif content_type == 'application/json':
            return self.parse_request_json(request.body.decode('utf-8'))
        elif content_type in ['application/x-www-form-urlencoded', 'multipart/form-data']:
            operations_json = request.POST.get('operations')
            map_json = request.POST.get('map')
            if operations_json and map_json:
                operations = self.parse_request_json(operations_json)
                map = self.parse_request_json(map_json)
                for file_id, f in request.FILES.items():
                    for name in map[file_id]:
                        segments = [maybe_int(s) for s in name.split('.')]
                        cur = operations
                        while len(segments) > 1:
                            cur = cur[segments.pop(0)]
                        cur[segments.pop(0)] = f
                logger.info('parse_body %s', operations)
                return operations
            else:
                return request.POST

        return {}