当使用AWS签名URL下载大型pdf文件时，可能会遇到浏览器无法打开的问题。这通常是由于超时或文件大小限制引起的。以下是解决此问题的步骤：

1. 通过AWS S3控制台或AWS CLI设置响应头部。

在AWS控制台或AWS CLI中，设置Content-Disposition响应头内容为“attachment”即可。

aws s3 cp s3://myBucket/myLargeFile.pdf - • --response-content-disposition="attachment"

这将在下载时自动触发下载对话框。

2. 使用分片下载。

将文件分片下载可避免下载的文件过大，从而提高下载速度。

以下是示例代码：

import boto3 import requests

s3 = boto3.resource('s3')

Get a client to interact with S3

client = boto3.client('s3')

Set the bucket and object key

bucket_name = 'myBucket' object_key = 'myLargeFile.pdf'

Generate a pre-signed URL for the S3 object

url = client.generate_presigned_url('get_object', Params={'Bucket': bucket_name, 'Key': object_key})

Open a new request to the pre-signed URL

req = requests.get(url, stream=True)

Get the total size of the file

total_size = int(req.headers.get('content-length', 0))

Define the chunk size you want to use

chunk_size = 1024 * 1024 # 1 MB

Define the number of chunks needed

num_chunks = total_size // chunk_size + (total_size % chunk_size > 0)

Define a function to read the response content in chunks

def read_chunk(): while True: data = req.raw.read(chunk_size, decode_content=True) if not data: break yield data

Stream the file in chunks to the client

response = app.response_class(read_chunk(), mimetype='application/pdf', headers={'Content-Disposition': 'inline'})

return response

通过这些步骤，您可以成功地在