第一次使用 Google 云存储。下面我有一个云函数，每当 csv 文件上传到时就会触发该函数my-folder在我的桶里。我的目标是在同一文件夹中创建一个新的 csv 文件，读取上传的 csv 的内容并将每一行转换为将进入新创建的 csv 的 URL。问题是我遇到了麻烦creating首先是新的 csv，更不用说实际写入它了。
My code:
import os.path
import csv
import sys
import json
from csv import reader, DictReader, DictWriter
from google.cloud import storage
from io import StringIO
def generate_urls(data, context):
if context.event_type == 'google.storage.object.finalize':
storage_client = storage.Client()
bucket_name = data['bucket']
bucket = storage_client.get_bucket(bucket_name)
folder_name = 'my-folder'
file_name = data['name']
if not file_name.endswith('.csv'):
return
接下来的几行来自一个例子 https://github.com/GoogleCloudPlatform/python-docs-samples/blob/master/storage/cloud-client/storage_compose_file.py在 GCP 的 GitHub 存储库中。这是我期望创建新的 csv 的时候，但什么也没有发生。
# Prepend 'URL_' to the uploaded file name for the name of the new csv
destination = bucket.blob(bucket_name + '/' + file_name[:14] + 'URL_' + file_name[14:])
destination.content_type = 'text/csv'
sources = [bucket.get_blob(file_name)]
destination.compose(sources)
output = bucket_name + '/' + file_name[:14] + 'URL_' + file_name[14:]
# Transform uploaded csv to string - this was recommended on a similar SO post, not sure if this works or is the right approach...
blob = bucket.blob(file_name)
blob = blob.download_as_string()
blob = blob.decode('utf-8')
blob = StringIO(blob)
input_csv = csv.reader(blob)
下一行是我收到错误的地方：No such file or directory: 'myProjectId/my-folder/URL_my_file.csv'
with open(output, 'w') as output_csv:
csv_dict_reader = csv.DictReader(input_csv, )
csv_writer = csv.DictWriter(output_csv, fieldnames=['URL'], delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
csv_writer.writeheader()
line_count = 0
for row in csv_dict_reader:
line_count += 1
url = ''
...
# code that converts each line
...
csv_writer.writerow({'URL': url})
print(f'Total rows: {line_count}')
如果有人对我如何创建新的 csv 然后写入它有任何建议，这将是一个巨大的帮助。谢谢你！
