python - 如何将 Django request.FILES （这是一个图像）作为二进制文件读取

问题描述

我想从请求中获取包含来自 ajax 的图像文件的二进制图像。

Senario - 当用户上传图像文件时，我想使用 google VISION API 对图像文件进行 OCR（光学字符识别）。为此，我需要将文件作为二进制文件读取。

背景 - 目前，在我的程序中，当用户上传图像时，文件通过 ajax 传递给 Django 视图。我试图在views.py 中获取一个二进制文件。当我使用request.FILES.get('file').read()时，没有数据。但是print(request.FILES.get('file').name)'bank.png'...我觉得很奇怪。

这是一些代码

视图.py

def receipt_ocr(request):
    if request.method == 'POST':
        print(type(request.FILES["file"]))              #<class 'django.core.files.uploadedfile.InMemoryUploadedFile'>
        print(type(request.FILES.get('file')))          #<class 'django.core.files.uploadedfile.InMemoryUploadedFile'>
        print(request.FILES.get('file'))                #bank.png
        imageFile = request.FILES.get('file')
        print(imageFile.size)                           #119227
        print(request.FILES.get('file').name)           #bank.png
        print(request.FILES.get('file').content_type)   #image/png
        print(type(request.FILES.get('file').open()))   #<class 'NoneType'>
        print(request.FILES.get('file').open())         #None
        print(type(request.FILES["file"].read()))       #<class 'bytes'>
        for chunk in imageFile.chunks():
            print(chunk)                               #this generates lot of binary and some rdf:Description rdf:about= ... things
        receipt_image = imageFile.read()
        print(type(receipt_image))
        print(receipt_image)

ajax部分


                // receipt OCR process
                $.ajax({
                    url: "{% url 'place:receipt_ocr' %}",
                    enctype: 'multipart/form-data',
                    type: 'POST',
                    processData: false,
                    contentType: false,
                    data: postData,
                    complete: function(req){
                        alert('good');
                    },
                    error: function(req, err){
                        alert('message:' + err);
                    }
                });

我真正想做的是使用这种代码（google VISION API 示例代码，OCR）

def detect_text(path):
    """Detects text in the file."""
    client = vision.ImageAnnotatorClient()

    with io.open(path, 'rb') as image_file:
        content = image_file.read() #read binary, save to content

    image = vision.types.Image(content=content)

    response = client.text_detection(image=image)
    texts = response.text_annotations
    print('Texts:')
    print(type(texts))

    for text in texts:
        print('\n"{}"'.format(text.description))

        vertices = (['({},{})'.format(vertex.x, vertex.y)
                    for vertex in text.bounding_poly.vertices])

        print('bounds: {}'.format(','.join(vertices)))

所以我想从请求中获取我的views.py中上述代码的“内容”。（我不需要使用这个函数本身。我将使用该函数的一部分）

如何在views.py 中获取二进制图像？我认为下面的代码会起作用，但它不起作用。我不知道为什么。

f = request.FILES.get('file')
receipt_image = f.read()
image = vision.types.Image(content=receipt_image)

感谢您的任何帮助和评论。

===添加===

“它不起作用”意味着我从日志中得到了这个 Traceback。

Internal Server Error: /mdd_event/receipt_ocr/ Traceback (most recent call last): File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\google\api_core\grpc_helpers.py", line 57, in error_remapped_callable return callable_(*args, **kwargs) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\grpc\_channel.py", line 565, in __call__ return _end_unary_response_blocking(state, call, False, None) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\grpc\_channel.py", line 467, in _end_unary_response_blocking raise _Rendezvous(state, None, None, deadline) grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with: status = StatusCode.INVALID_ARGUMENT details = "Request must specify image and features." debug_error_string = "{"created":"@1566165461.211000000","description":"Error received from peer ipv4:216.58.197.234:443","file":"src/core/lib/surface/call.cc","file_line":1052,"grpc_message":"Request must specify image and features.","grpc_status":3}" > 
The above exception was the direct cause of the following exception: Traceback (most recent call last): 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\django\core\handlers\exception.py", line 41, in inner response = get_response(request) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\django\core\handlers\base.py", line 187, in _get_response response = self.process_exception_by_middleware(e, request) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\django\core\handlers\base.py", line 185, in _get_response response = wrapped_callback(request, *callback_args, **callback_kwargs) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\django\contrib\auth\decorators.py", line 23, in _wrapped_view return view_func(request, *args, **kwargs) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\django\contrib\auth\decorators.py", line 23, in _wrapped_view return view_func(request, *args, **kwargs) 
File "C:\Users\user\liam\dev\git\mdd_bean\mdd_event\views.py", line 530, in receipt_ocr response = client.text_detection(image=image) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\google\cloud\vision_helpers\decorators.py", line 101, in inner response = self.annotate_image(request, retry=retry, timeout=timeout) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\google\cloud\vision_helpers\__init__.py", line 72, in annotate_image r = self.batch_annotate_images([request], retry=retry, timeout=timeout) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\google\cloud\vision_v1\gapic\image_annotator_client.py", line 274, in batch_annotate_images request, retry=retry, timeout=timeout, metadata=metadata File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\google\api_core\gapic_v1\method.py", line 143, in __call__ return wrapped_func(*args, **kwargs) 
File "C:\Users\user\liam\dev\git\mdd_bean_env\lib\site-packages\google\api_core\grpc_helpers.py", line 59, in error_remapped_callable six.raise_from(exceptions.from_grpc_error(exc), exc) 
File "<string>", line 3, in raise_from google.api_core.exceptions.InvalidArgument: 400 Request must specify image and features.

标签： pythondjangodjango-modelsrequest

python - 如何将 Django request.FILES （这是一个图像）作为二进制文件读取

问题描述

解决方案

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