Context

Runtime differences

Python 3.12 restructures the context object from earlier runtimes (3.10, 3.9, 3.6).

Feature	Python 3.12	Python 3.10, 3.9, 3.6
`credentials` field	Removed. Use environment variables.	Available as `Credentials` struct.
`service` struct	Removed. `log_project`, `log_store`, `qualifier`, and `version_id` moved to `FunctionMeta` or top-level context.	Available as `ServiceMeta` struct.
`logger` field	Available on the context object.	Not available.
`FunctionMeta` fields	6 fields: `name`, `handler`, `memory`, `timeout`, `version_id`, `qualifier`.	4 fields: `name`, `handler`, `memory`, `timeout`.

Python 3.12

Context properties

Property	Type	Description
`request_id`	String	Unique request identifier. Record for troubleshooting.
`function`	`FunctionMeta`	Invoked function metadata. FunctionMeta fields.
`region`	String	Region ID, such as `cn-shanghai` for China (Shanghai). Endpoints.
`logger`	Logger	Logger for function execution. Initially `None`; call `context.getLogger()` to obtain a `logging.Logger`.
`account_id`	String	ID of the Alibaba Cloud account that owns the function.
`log_project`	String	Simple Log Service project name associated with the function.
`log_store`	String	Simple Log Service Logstore name associated with the function.

FunctionMeta fields (Python 3.12)

Field	Description
`name`	Function name.
`handler`	Handler entry point.
`memory`	Memory allocated to the function, in MB.
`timeout`	Maximum execution time, in seconds.
`version_id`	Version of the function being invoked.
`qualifier`	Version or alias specified when the function was invoked.

Credentials migration

Important

The credentials field is removed in Python 3.12. Use environment variables instead.

To access other Alibaba Cloud services, use these environment variables:

Environment variable	Description
`ALIBABA_CLOUD_ACCESS_KEY_ID`	Temporary AccessKey ID.
`ALIBABA_CLOUD_ACCESS_KEY_SECRET`	Temporary AccessKey Secret.
`ALIBABA_CLOUD_SECURITY_TOKEN`	Security token.

Configure environment variables.

Before and after comparison:

# Python 3.10 and earlier -- credentials from context
def handler(event, context):
    creds = context.credentials
    access_key_id = creds.access_key_id
    access_key_secret = creds.access_key_secret
    security_token = creds.security_token

# Python 3.12 -- credentials from environment variables
import os

def handler(event, context):
    access_key_id = os.environ['ALIBABA_CLOUD_ACCESS_KEY_ID']
    access_key_secret = os.environ['ALIBABA_CLOUD_ACCESS_KEY_SECRET']
    security_token = os.environ['ALIBABA_CLOUD_SECURITY_TOKEN']

Context class definition

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

import json


class FunctionMeta:
    def __init__(self, name, handler, memory, timeout, version_id, qualifier):
        self.name = name
        self.handler = handler
        self.memory = memory
        self.timeout = timeout
        self.version_id = version_id
        self.qualifier = qualifier


class FCContext:
    def __init__(self, account_id, request_id, function_meta, logger, log_project, log_store,
                 region):
        self.account_id = account_id
        self.request_id = request_id
        self.function = function_meta
        self.logger = logger
        self.log_project = log_project
        self.log_store = log_store
        self.region = region

Python 3.10, 3.9, and 3.6

Context properties

Property	Type	Description
`request_id`	String	Unique request identifier. Record for troubleshooting.
`credentials`	`Credentials`	Temporary credentials from the AssumeRole API, valid for 36 hours. Access other Alibaba Cloud services without embedding an AccessKey pair. Credentials fields. Grant Function Compute permissions to access other Alibaba Cloud services.
`function`	`FunctionMeta`	Invoked function metadata. FunctionMeta fields.
`service`	`ServiceMeta`	Service metadata. ServiceMeta fields.
`region`	String	Region ID, such as `cn-shanghai` for China (Shanghai). Endpoints.
`account_id`	String	ID of the Alibaba Cloud account that owns the function.

Credentials fields

Field	Description
`access_key_id`	Temporary AccessKey ID.
`access_key_secret`	Temporary AccessKey Secret.
`security_token`	Security token.

After you assign a RAM role to a function, Function Compute obtains temporary credentials through the AssumeRole API. These credentials are valid for 36 hours and allow the function to access other Alibaba Cloud services without an embedded AccessKey pair.

FunctionMeta fields (Python 3.10, 3.9, and 3.6)

Field	Description
`name`	Function name.
`handler`	Handler entry point.
`memory`	Memory allocated to the function, in MB.
`timeout`	Maximum execution time, in seconds.

ServiceMeta fields

Field	Description
`log_project`	Simple Log Service project name.
`log_store`	Simple Log Service Logstore name.
`qualifier`	Version or alias of the service specified when the function was invoked.
`version_id`	Version of the service that was actually invoked.

qualifier is the version or alias from the invocation request; version_id is the version actually executed. They differ when an alias resolves to a specific version.

Context class definition

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

import json


class Credentials:
    def __init__(self, access_key_id, access_key_secret, security_token):
        self.access_key_id = access_key_id
        self.access_key_secret = access_key_secret
        self.security_token = security_token


class Tracing:
    def __init__(self, span_context, base64_baggages, jaeger_endpoint):
        self.span_context = span_context
        self.jaeger_endpoint = jaeger_endpoint
        self.span_baggages = self.parseOpenTracingBaggages(base64_baggages)

    def parseOpenTracingBaggages(self, base64_baggages):
        span_baggages = {}
        # None || '' returns false
        if base64_baggages:
            try:
                import base64
                str_baggages = base64.b64decode(base64_baggages)
                span_baggages = json.loads(str_baggages)
            except Exception as e:
                import logging
                fc_sys_logger = logging.getLogger('fc_sys_logger')
                fc_sys_logger.error('Failed to parse base64 opentracing baggages:[{}], err: {}'.format(base64_baggages, e))
        return span_baggages


class FunctionMeta:
    def __init__(self, name, handler, memory, timeout):
        self.name = name
        self.handler = handler
        self.memory = memory
        self.timeout = timeout


class FCContext:
    def __init__(self, account_id, request_id, credentials, function_meta, service_meta, region, tracing):
        self.credentials = credentials
        self.function = function_meta
        self.request_id = request_id
        self.service = service_meta
        self.region = region
        self.account_id = account_id
      # self.tracing = tracing

Example

Example 2: Read and write OSS resources using a temporary AccessKey pair.