Object Storage Service:Handle exceptions (Python SDK V1)

Exception handling example

The following code shows how to handle an exception when you download a file that does not exist. It prints the HTTP status code and request ID from the error message.

# -*- coding: utf-8 -*-
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

# Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set.
auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())

# Set the Endpoint for the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the Endpoint to https://oss-cn-hangzhou.aliyuncs.com.
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
# Set the region that corresponds to the Endpoint, for example, cn-hangzhou. Note: This parameter is required for V4 signatures.
region = "cn-hangzhou"

# Replace examplebucket with the name of your bucket.
bucket = oss2.Bucket(auth, endpoint, "examplebucket", region=region)

try:
    # Set the name of the file to download, for example, exampleobject.txt.
    stream = bucket.get_object('exampleobject.txt')
except oss2.exceptions.NoSuchKey as e:
    print('status={0}, request_id={1}'.format(e.status, e.request_id))            

ClientError

A ClientError is caused by invalid client input. For example, this exception is thrown if you provide an empty file list to the `bucket.batch_delete_objects` method. The `status` value for a ClientError is `oss2.exceptions.OSS_CLIENT_ERROR_STATUS`.

RequestError

When the HTTP library throws an exception, the Python SDK converts it to a RequestError. The `status` value for a RequestError is `oss2.exceptions.OSS_REQUEST_ERROR_STATUS`.

ServerError

When the OSS server returns an HTTP error code, the Python SDK converts it to a ServerError. ServerError has multiple child classes that are derived from HTTP status codes and OSS error codes. For example, the NotFound child class corresponds to all 404 exceptions, and the Conflict child class corresponds to all 409 exceptions.

The following table lists common error codes.