read excel files from “input” blob storage container and export to csv in “output” container with python

问题

I'm trying to develop a script in python to read a file in .xlsx from a blob storage container called "source", convert it in .csv and store it in a new container (i'm testing the script locally, if working I should include it in an ADF pipeline). Sofar I managed to access to the blob storage, but I'm having problems in reading the file content.

from azure.storage.blob import BlobServiceClient, ContainerClient, BlobClient
import pandas as pd

conn_str = "DefaultEndpointsProtocol=https;AccountName=XXXXXX;AccountKey=XXXXXX;EndpointSuffix=core.windows.net"
container = "source"
blob_name = "prova.xlsx"

container_client = ContainerClient.from_connection_string(
    conn_str=conn_str, 
    container_name=container
    )
# Download blob as StorageStreamDownloader object (stored in memory)
downloaded_blob = container_client.download_blob(blob_name)

df = pd.read_excel(downloaded_blob)

print(df)

I get following error:

ValueError: Invalid file path or buffer object type: <class 'azure.storage.blob._download.StorageStreamDownloader'>

I tried with a .csv file as input and writing the parsing code as follows

df = pd.read_csv(StringIO(downloaded_blob.content_as_text()) )

and it works.

Any suggestion on how to modify the code so that the Excel file become readable?

回答1:

I summary the solution as below.

When we use the method pd.read_excel() in sdk pandas, we need to provide bytes as input. But when we use download_blob to download the excel file from azure blob, we just get azure.storage.blob.StorageStreamDownloader. So we need to use the method readall() or content_as_bytes() to convert it to bytes. For more details, please refer to the document and the document

来源：https://stackoverflow.com/questions/61752574/read-excel-files-from-input-blob-storage-container-and-export-to-csv-in-outpu