S3_REGION="eu-central-1"
bucket="mybucket1"
name="objectname"

import boto3
from botocore.client import Config
client = boto3.client('s3',region_name=S3_REGION,config=Config(signature_version='s3v4'))
list = client.list_objects_v2(Bucket=bucket,Prefix=name)
for obj in list.get('Contents', []):
    if obj['Key'] == name: return True
return False

这里有一个对我有用的解决办法。需要注意的是，我事先知道密钥的确切格式，所以我只列出单个文件

import boto3

# The s3 base class to interact with S3
class S3(object):
  def __init__(self):
    self.s3_client = boto3.client('s3')

  def check_if_object_exists(self, s3_bucket, s3_key):
    response = self.s3_client.list_objects(
      Bucket = s3_bucket,
      Prefix = s3_key
      )
    if 'ETag' in str(response):
      return True
    else:
      return False

if __name__ == '__main__':
  s3  = S3()
  if s3.check_if_object_exists(bucket, key):
    print "Found S3 object."
  else:
    print "No object found."

您可以使用awswrangler在一行中完成它。

awswrangler.s3.does_object_exist(path_of_object_to_check)

https://aws-data-wrangler.readthedocs.io/en/stable/stubs/awswrangler.s3.does_object_exist.html

does_object_exist方法使用s3客户机的head_object方法并检查是否引发了ClientError。如果错误代码是404，则返回False。

试试这个简单的方法

import boto3
s3 = boto3.resource('s3')
bucket = s3.Bucket('mybucket_name') # just Bucket name
file_name = 'A/B/filename.txt'      # full file path
obj = list(bucket.objects.filter(Prefix=file_name))
if len(obj) > 0:
    print("Exists")
else:
    print("Not Exists")

S3_REGION="eu-central-1"
bucket="mybucket1"
name="objectname"

import boto3
from botocore.client import Config
client = boto3.client('s3',region_name=S3_REGION,config=Config(signature_version='s3v4'))
list = client.list_objects_v2(Bucket=bucket,Prefix=name)
for obj in list.get('Contents', []):
    if obj['Key'] == name: return True
return False

get()方法非常简单

import botocore
from boto3.session import Session
session = Session(aws_access_key_id='AWS_ACCESS_KEY',
                aws_secret_access_key='AWS_SECRET_ACCESS_KEY')
s3 = session.resource('s3')
bucket_s3 = s3.Bucket('bucket_name')

def not_exist(file_key):
    try:
        file_details = bucket_s3.Object(file_key).get()
        # print(file_details) # This line prints the file details
        return False
    except botocore.exceptions.ClientError as e:
        if e.response['Error']['Code'] == "NoSuchKey": # or you can check with e.reponse['HTTPStatusCode'] == '404'
            return True
        return False # For any other error it's hard to determine whether it exists or not. so based on the requirement feel free to change it to True/ False / raise Exception

print(not_exist('hello_world.txt'))