Object Storage Service:Image styles (Python SDK V1)

Prerequisites

Before you begin, ensure that you have:

• An OSS bucket

• Access credentials configured as environment variables (OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET). See Configure access credentials using OSS SDK for Python 1.0

• The RAM permissions required for the operations you want to perform (see Permissions below)

Permissions

An Alibaba Cloud account has the required permissions by default. To perform image style operations as a Resource Access Management (RAM) user or with Security Token Service (STS), grant the following permissions:

For details, see Grant custom access policies to a RAM user.

Operations

Client initialization

All examples use the same client initialization pattern. Replace examplebucket and the endpoint with your own values.

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

# Load access credentials from environment variables.
# Set OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running any example.
auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())

# Set the endpoint for the region where your bucket is located.
# Example: China (Hangzhou) region uses https://oss-cn-hangzhou.aliyuncs.com.
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"

# Set the region that matches the endpoint. Required for V4 signatures.
region = "cn-hangzhou"

bucket = oss2.Bucket(auth, endpoint, "examplebucket", region=region)

The examples use the public endpoint for China (Hangzhou). To access OSS from another Alibaba Cloud service in the same region, use the internal endpoint instead. See Regions and endpoints.

To create an OSSClient instance using a custom domain name or STS, see Initialization.

Create an image style

A bucket supports up to 50 image styles.

Method: bucket.put_bucket_style(style, content)

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

auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
region = "cn-hangzhou"
bucket = oss2.Bucket(auth, endpoint, "examplebucket", region=region)

# Name of the image style to create.
style = 'imagestyle'

# Define the operations the style applies. This example resizes images to a width of 200 pixels.
content = 'image/resize,w_200'

result = bucket.put_bucket_style(style, content)
print('The style is created. The status code is: ' + str(result.status))

After creating a style, apply it to images in the bucket. See Use image styles to process images.

For the full list of supported image processing parameters, see Image processing.

Get an image style

Method: bucket.get_bucket_style(style)

Response fields:

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

auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
region = "cn-hangzhou"
bucket = oss2.Bucket(auth, endpoint, "examplebucket", region=region)

style = 'imagestyle'

result = bucket.get_bucket_style(style)
print('name: ' + result.name)
print('content: ' + result.content)

List all image styles

Method: bucket.list_bucket_style()

Returns all image styles in the bucket. Each item in result.styles has name and content fields.

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

auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
region = "cn-hangzhou"
bucket = oss2.Bucket(auth, endpoint, "examplebucket", region=region)

result = bucket.list_bucket_style()
for sty in result.styles:
    print('name: ' + sty.name)
    print('content: ' + sty.content)

Delete an image style

Method: bucket.delete_bucket_style(style)

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

auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"
region = "cn-hangzhou"
bucket = oss2.Bucket(auth, endpoint, "examplebucket", region=region)

style = 'imagestyle'

result = bucket.delete_bucket_style(style)
print('Style deleted successfully. Return status: ' + str(result.status))

What's next

• Use image styles to process images

• Image processing