Configure single-connection bandwidth throttling using OSS SDK for Python - Object Storage Service: Central de Documentação do Alibaba Cloud

Este tópico descreve como adicionar parâmetros em uma solicitação de upload ou download de um objeto para definir o limite de largura de banda. Isso garante largura de banda suficiente para outros aplicativos.

Observações

Este tópico usa o endpoint público da região China (Hangzhou). Para acessar o OSS a partir de outros serviços da Alibaba Cloud na mesma região, use um endpoint interno. Para obter mais informações sobre as regiões e endpoints do OSS, consulte Regions and endpoints.
Neste exemplo, obtemos as credenciais de acesso a partir de variáveis de ambiente. Para obter mais informações sobre como configurar credenciais de acesso, consulte Configure access credentials using OSS SDK for Python 1.0.
O código demonstra como criar uma instância OSSClient com um endpoint do OSS. Para configurações alternativas, como usar um domínio personalizado ou autenticar-se com credenciais do Security Token Service (STS), consulte Initialization.

Configure a limitação de largura de banda de conexão única para upload e download simples

O código de exemplo a seguir mostra como configurar a limitação de largura de banda de conexão única para upload e download simples:

# -*- coding: utf-8 -*-

import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider
from oss2.models import OSS_TRAFFIC_LIMIT

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

# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
# Specify the ID of the region that maps to the endpoint. Example: cn-hangzhou. This parameter is required if you use the signature algorithm V4.
region = "cn-hangzhou"

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

# Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir/exampleobject.txt. 
object_name = 'exampledir/exampleobject.txt'
# Specify the full path of the local file that you want to upload. Example: D:\\localpath\\examplefile.txt. By default, if you do not specify the path of the local file, the local file is uploaded from the path of the project to which the sample program belongs. 
local_file_name = 'D:\\localpath\\examplefile.txt'
# Specify the local path to which you want to download the object. If a file that has the same name already exists, the downloaded object overwrites the file. If no file that has the same name exists, the downloaded object is saved in the path. 
# If you do not specify a path for the downloaded object, the downloaded object is saved to the path of the project to which the sample program belongs. 
down_file_name = 'D:\\localpath\\exampleobject.txt'

# Configure the headers parameter to set the bandwidth limit to 100 KB/s, which is equal to 819,200 bit/s. 
limit_speed = (100 * 1024 * 8)
headers = dict()
headers[OSS_TRAFFIC_LIMIT] = str(limit_speed)

# Configure bandwidth throttling for object upload. 
result = bucket.put_object_from_file(object_name, local_file_name, headers=headers)
print('http response status:', result.status)

# Configure bandwidth throttling for object download. 
result = bucket.get_object_to_file(object_name, down_file_name, headers=headers)
print('http response status:', result.status)

Configure a limitação de largura de banda de conexão única para upload de múltiplas partes

O código de exemplo a seguir mostra como configurar a limitação de largura de banda de conexão única para upload de múltiplas partes:

# -*- coding: utf-8 -*-
import os
from oss2 import SizedFileAdapter, determine_part_size
from oss2.headers import OSS_TRAFFIC_LIMIT
from oss2.models import PartInfo
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

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

# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
# Specify the ID of the region that maps to the endpoint. Example: cn-hangzhou. This parameter is required if you use the signature algorithm V4.
region = "cn-hangzhou"

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

# Specify the full path of the object. The full path of the object cannot contain the bucket name. Example: exampledir/exampleobject.txt. 
key = 'exampledir/exampleobject.txt'
# Specify the full path of the local file that you want to upload. Example: D:\\localpath\\examplefile.txt. 
filename = 'D:\\localpath\\examplefile.txt'

total_size = os.path.getsize(filename)
# Use the determine_part_size method to determine the part size. 
part_size = determine_part_size(total_size, preferred_size=100 * 1024)

# Initiate a multipart upload task. 
upload_id = bucket.init_multipart_upload(key).upload_id
parts = []

# Configure the headers parameter to set the bandwidth limit to 100 KB/s, which is equal to 819,200 bit/s. 
limit_speed = (100 * 1024 * 8)
headers = dict()
headers[OSS_TRAFFIC_LIMIT] = str(limit_speed)

# Upload the parts one by one. 
with open(filename, 'rb') as fileobj:
    part_number = 1
    offset = 0
    while offset < total_size:
        num_to_upload = min(part_size, total_size - offset)
        # Call the SizedFileAdapter(fileobj, size) method to generate a new object and recalculate the position from which the append operation starts. 
        result = bucket.upload_part(key, upload_id, part_number,
                                    SizedFileAdapter(fileobj, num_to_upload), headers=headers)
        parts.append(PartInfo(part_number, result.etag))

        offset += num_to_upload
        part_number += 1

# Complete the multipart upload task. 
# The following code provides an example on how to configure headers when you complete the multipart upload task: 
headers = dict()
# Specify the access control list (ACL) of the object. In this example, this parameter is set to OBJECT_ACL_PRIVATE, which indicates that the ACL of the object is private. 
# headers["x-oss-object-acl"] = oss2.OBJECT_ACL_PRIVATE
bucket.complete_multipart_upload(key, upload_id, parts, headers=headers)
# bucket.complete_multipart_upload(key, upload_id, parts)

# Verify the result of the multipart upload task. 
with open(filename, 'rb') as fileobj:
    assert bucket.get_object(key).read() == fileobj.read()

Configure a limitação de largura de banda para upload e download que usam URLs assinadas

O código de exemplo a seguir mostra como configurar a limitação de largura de banda de conexão única ao usar URLs assinadas para fazer upload ou download de objetos:

# -*- coding: utf-8 -*-

import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider
from oss2.models import OSS_TRAFFIC_LIMIT

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

# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
# Specify the ID of the region that maps to the endpoint. Example: cn-hangzhou. This parameter is required if you use the signature algorithm V4.
region = "cn-hangzhou"

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

# Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir/exampleobject.txt. 
object_name = 'exampledir/exampleobject.txt'
# Specify the full path of the local file that you want to upload. Example: D:\\localpath\\examplefile.txt. By default, if you do not specify the path of the local file, the local file is uploaded from the path of the project to which the sample program belongs. 
local_file_name = 'D:\\localpath\\examplefile.txt'
# Specify the local path to which you want to download the object. If a file that has the same name already exists, the downloaded object overwrites the file. If no file that has the same name exists, the downloaded object is saved in the path. 
# If you do not specify a path for the downloaded object, the downloaded object is saved to the path of the project to which the sample program belongs. 
down_file_name = 'D:\\localpath\\exampleobject.txt'

# Configure the params parameter to set the bandwidth limit to 100 KB/s, which is equal to 819,200 bit/s. 
limit_speed = (100 * 1024 * 8)
params = dict()
params[OSS_TRAFFIC_LIMIT] = str(limit_speed)

# Generate a signed URL that includes the bandwidth throttling parameter for object upload and set the validity period of the URL to 60 seconds. 
url = bucket.sign_url('PUT', object_name, 60, params=params)
print('put object url:', url)

# Configure bandwidth throttling for object upload. 
result = bucket.put_object_with_url_from_file(url, local_file_name)
print('http response status:', result.status)

# Generate a signed URL that includes the bandwidth throttling parameter for object download and set the validity period of the URL to 60 seconds. 
url = bucket.sign_url('GET', object_name, 60, params=params)
print('get object url:', url)

# Configure bandwidth throttling for object download. 
result = bucket.get_object_with_url_to_file(url, down_file_name)
print('http response status:', result.status)

Referências

Para obter o código de exemplo completo para limitação de largura de banda de conexão única, acesse o GitHub.