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SDK For Python

Last updated: 2023-09-27 21:25:07

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Tencentserverless SDK Overview

Tencentserverless is a Tencent Cloud SCF SDK that integrates SCF business flow APIs to make it easier to invoke SCF functions. It allows users to invoke a function quickly from a local system, CVM instance, container or function, eliminating the need to encapsulate APIs in a public cloud.

Features

Tencentserverless SDK has the following features:
It can invoke functions in a high-performance, low-latency manner.
Enables quick invocation across functions after the required parameters are entered (it will obtain parameters in environment variables by default, such as region and SecretId).
Supports access with private network domain names.
Supports session keep-alive.
It supports cross-region function invocation.
Supports native invocation methods in Python.
Note
Calling SDK across functions is only applicable to event-triggered functions. HTTP-triggered functions can be invoked by requesting the corresponding path of the function in the function code.

Quick Start

Mutual function invocation

Sample

Note
To implement mutual recursion of functions in different regions, you need to specify the region. For the naming rules, please see Region List.
If no region is specified, intra-region mutual function invocation will be used by default.
If no namespace is specified, default will be used by default.
1. Create a Python cloud function on the cloud, named "FuncInvoked" in the Guangzhou region. The function content is as follows:
# -*- coding: utf8 -*-

def main_handler(event, context):
 if 'key1' in event.keys():
     print("value1 = " + event['key1'])
 if 'key2' in event.keys():
     print("value2 = " + event['key2'])
 return "Hello World from the function being invoked"  #return

2. Create a Python cloud function on the cloud, named "PythonInvokeTest" in the Chengdu region. You can edit the PythonInvokeTest function in one of the following two ways, depending on your actual situation.
Method 1. If you don't need to invoke the function frequently, you can use the following sample code:
from tencentserverless import scf 
from tencentserverless.scf import Client
from tencentserverless.exception import TencentServerlessSDKException
from tencentcloud.common.exception.tencent_cloud_sdk_exception import TencentCloudSDKException

def main_handler(event, context):
    print("prepare to invoke a function!")
    try:
        data = scf.invoke('FuncInvoked',region="ap-guangzhou",data={"a": "b"})
        print (data)
    except TencentServerlessSDKException as e:
        print (e)
    except TencentCloudSDKException as e:
        print (e)
    except Exception as e:
        print (e)
    return "Already invoked a function!" # return


The output is as follows:
"Already invoked a function!"
Method 2. If you need to invoke the function frequently, you can choose to connect and trigger it through Client by using the following sample code:
# -*- coding: utf8 -*-

from tencentserverless import scf 
from tencentserverless.scf import Client
from tencentserverless.exception import TencentServerlessSDKException
from tencentcloud.common.exception.tencent_cloud_sdk_exception import TencentCloudSDKException

def main_handler(event, context):
    #scf = Client(region="ap-guangzhou") # To connect using this method, please enable the "Execution Role" feature in the function configuration, and select an execution role with function invocation permissions.
    scf = Client(secret_id="AKIxxxxxxxxxxxxxxxxxxxxxxggB4Sa", secret_key="3vZzxxxxxxxxxxxaeTC", region="ap-guangzhou", token="") # To connect using this method, please replace the secret_id and secret_key with your own. This pair of keys needs to include the permission to invoke the function.
    print("prepare to invoke a function!")
    try:
        data = scf.invoke('FuncInvoked',data={"a":"b"})
        data = scf.FuncInvoked(data={"a": "b"}) # To use the native Python invocation method, you need to initialize it through Client first.
        print (data)
    except TencentServerlessSDKException as e:
        print (e)
    except TencentCloudSDKException as e:
        print (e)
    except Exception as e:
        print (e)
    return "Already invoked a function!" # return

The output is as follows:
"Already invoked a function!"
Note
Secret_id and secret_key refer to the ID and Key of the Cloud API. You can obtain or create the relevant keys by logging into the Access Management Console, selecting Cloud API Keys, and then API Key Management.

Local function invocation

Development Preparations

Development Environment: Python 2.7 or Python 3.6 should be installed.
Runtime Environment: The tencentserverless SDK should be installed, and it supports Windows, Linux, and Mac operating systems.
Note
For local function invocation, you must complete the above preparations. We recommend you develop the function locally and then upload it to the cloud and use mutual function invocation for debugging.

Installation through pip (recommended)

Run the following command to install Tencentserverless SDK for Python.
pip install tencentserverless

Installing through source package

Download the latest source code package from the Github repository. After decompressing the source code package, run the following commands in sequence to install.
cd tencent-serverless-python-master
python setup.py install

Configuring Tencentserverless SDK for Python

Run the following command to upgrade Tencentserverless SDK for Python.
pip install tencentserverless -U
Run the following command to view the information of Tencentserverless SDK for Python.
pip show tencentserverless

Sample

1. Create a Python cloud function on the cloud, named "FuncInvoked" in the Guangzhou region. The function content is as follows:
# -*- coding: utf8 -*-

def main_handler(event, context):
 if 'key1' in event.keys():
     print("value1 = " + event['key1'])
 if 'key2' in event.keys():
     print("value2 = " + event['key2'])
 return "Hello World from the function being invoked"  #return
2. Create a local file named PythonInvokeTest.py with the following content:
# -*- coding: utf8 -*-

from tencentserverless import scf 
from tencentserverless.scf import Client
from tencentserverless.exception import TencentServerlessSDKException
from tencentcloud.common.exception.tencent_cloud_sdk_exception import TencentCloudSDKException

def main_handler(event, context):
 print("prepare to invoke a function!")
 scf = Client(secret_id="AKIxxxxxxxxxxxxxxxxxxxxxxggB4Sa", secret_key="3vZzxxxxxxxxxxxaeTC", region="ap-guangzhou", token="") # Replace with your own secret_id and secret_key
 try:
     data = scf.invoke('FuncInvoked',data={"a":"b"}) 
     # data = scf.FuncInvoked(data={"a":"b"}) 
     print (data)
 except TencentServerlessSDKException as e:
     print (e)
 except TencentCloudSDKException as e:
     print (e)
 except Exception as e:
     print (e)
 return "Already invoked a function!" # return

main_handler("","")


Go to the directory where the PythonInvokeTest.py file is located and run the following command to view the result.
python PythonInvokeTest.py
The output is as follows:
prepare to invoke a function!"Hello World form the function being invoked"

API List

API Reference

Client (class)
invoke (method)
TencentserverlessSDKException (class)

Client

Method:
__init__
Parameter information:
Parameter
Required
Local Disk Types
Description
region
Not required
String
Region, which is the same as the region of the function invoking the API and is Guangzhou for local invocations by default.
secret_id
Not required
String
User SecretId, which is obtained from the function's environment variable by default and is required for local debugging.
secret_key
Not required
String
User SecretKey, which is obtained from the function's environment variable by default and is required for local debugging.
token
Not required
String
User token, which is obtained from the function's environment variable by default.
invoke
Parameter information:
Parameter
Required
Local Disk Types
Description
function_name
Supported
String
Function name.
qualifier
Not required
String
Function version. Default value: $LATEST.
data
Not required
Object
Input parameter for function execution, which must be an object that can be processed by json.dumps.
namespace
Not required
String
Namespace. Default value: default.

invoke

This is used to invoke a function. Currently, only sync invocation is supported.
Parameter information:
Parameter
Required
Local Disk Types
Description
region
Not required
String
Region, which is the same as the region of the function invoking the API and is Guangzhou for local invocations by default.
secret_id
Not required
String
User SecretId, which is obtained from the function's environment variable by default and is required for local debugging.
secret_key
Not required
String
User SecretKey, which is obtained from the function's environment variable by default and is required for local debugging.
token
Not required
String
User token, which is obtained from the function's environment variable by default.
function_name
Supported
String
Function name.
qualifier
Not required
String
Function version. Default value: $LATEST.
data
Not required
String
Input parameter for function execution, which must be an object that can be processed by json.dumps.
namespace
Not required
String
Namespace. Default value: default.

TencentserverlessSDKException

Attributes:
[code]
[message]
[request_id]
[response]
[stack_trace]
Methods and descriptions:
Method Name
Description
get_code
Returns error code
get_message
Returns error message
get_request_id
Returns RequestId
get_response
Returns response
get_stack_trace
Returns stack_trace
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