Open An Azure Storagestreamdownloader Without Saving It As A File

I need to download a PDF from a blob container in azure as a download stream (StorageStreamDownloader) and open it in both PDFPlumber and PDFminer. I developed all the requirements

Solution 1:

download_blob() download the blob to a StorageStreamDownloader class, and in this class there is a download_to_stream, with this you will get the blob stream.

from azure.storage.blob import BlobServiceClient, BlobClient, ContainerClient
from io import BytesIO
import PyPDF2
filename = "test.pdf"

container_name="test"

blob_service_client = BlobServiceClient.from_connection_string("connection string")
container_client=blob_service_client.get_container_client(container_name)
blob_client = container_client.get_blob_client(filename)
streamdownloader=blob_client.download_blob()

stream = BytesIO()
streamdownloader.download_to_stream(stream)

fileReader = PyPDF2.PdfFileReader(stream)

print(fileReader.numPages)

And this is my result. It will print the pdf pages number.

Solution 2:

It seems download_to_stream() is now deprecated and instead should be used readinto().

from azure.storage.blob import BlobClient


conn_string = ''
container_name = ''
blob_name = ''
blob_obj = BlobClient.from_connection_string(
    conn_str=conn_string, container_name=container_name,
    blob_name=blob_name
)
withopen(blob_name, 'wb') as f:
    b = blob_obj.download_blob()
    b.readinto(f)

This will create a file in working directory with the data that was downloaded.

Solution 3:

simply add readall() to the download_blob() which will read the data as bytes.

from azure.storage.blob import BlobClient
conn_string = ''
container_name = ''
blob_name = ''
blob_obj = 
BlobClient.from_connection_string(conn_string,container_name,blob_name)
withopen(blob_name, 'wb') as f:
    b = blob_obj.download_blob().readall()