Creating an Event Function

Overview

A function is customized code for processing events. You can create a function from scratch and configure the function based on site requirements.

FunctionGraph manages the compute resources required for function execution. After editing code for your function, configure compute resources on the FunctionGraph console.

You can create a function from scratch or by using a template or container image.

When creating a function from scratch, configure the basic and code information based on Table 1. The parameters marked with an asterisk (*) are mandatory.

Each FunctionGraph function runs in its own environment and has its own resources and file system.

Prerequisites

1. You must be familiar with the programming languages supported by FunctionGraph. For details, see Supported Programming Languages.
2. You have created a deployment package. For details, see Creating a Deployment Package.
3. (Optional) You have created an agency. For details, see Configuring Agency Permissions.

Procedure

1. Log in to the FunctionGraph console. In the navigation pane, choose Functions > Function List.
2. On the Function List page, click Create Function in the upper right corner.
3. Click Create from scratch and configure the function information by referring to Table 1. The parameters marked with an asterisk (*) are mandatory.
   Figure 1 Creating a function from scratch
   

   Table 1 Basic information

   Parameter	Description
   * Function Type	Event functions: triggered by triggers. HTTP functions: triggered once HTTP requests are sent to specific URLs. NOTE: HTTP functions do not distinguish between programming languages. The handler must be set in the bootstrap file. You can directly write the startup command, and allow access over port 8000. HTTP functions support APIG and APIC triggers only. For details about how to use HTTP functions, see Creating an HTTP Function.
   *Region	Select a region where you will deploy your code.
   *Function Name	Name of the function, which must meet the following requirements: Consists of 1 to 60 characters, and can contain letters, digits, hyphens (-), and underscores (_). Starts with a letter and ends with a letter or digit.
   Agency	An agency is required if FunctionGraph accesses other cloud services. For details on how to create an agency, see Configuring Agency Permissions. No agency is required if FunctionGraph does not access any cloud services.
   *Enterprise Project	Select a created enterprise project and add the function to it. By default, default is selected.
   Runtime	Select a runtime to compile the function. NOTICE: CloudIDE supports Node.js and Python only.

4. Click Create Function. On the displayed Code tab page, continue to configure the code.

Configuring Code

1. You can deploy the code based on the runtime you select. For details, see Creating a Deployment Package. After the deployment is complete, click Deploy.

   As shown in the following example, to deploy code in Node.js 10.16, you can edit code inline, upload a local ZIP file, or upload a ZIP file from OBS.

   Figure 2 Deploying code
   
   Figure 3 Deploying code
   
2. You can modify the code and click Deploy to deploy the code again.

Viewing Code Information

1. View code attributes.

   Code attributes show the code size and the time the code was modified.

   Figure 4 Viewing code attributes
   
2. View basic information.

   Configuring Basic Settings shows the default memory and execution timeout in each runtime. You can click Edit to switch to the Basic Settings page and modify Handler, Memory (MB), and Execution Timeout (s) as required. For details, see Figure 5.

   Figure 5 Editing basic information
   
   

   Once a function is created, the runtime cannot be changed.

   Table 2 Default basic information of each runtime

   Runtime	Default Basic Information
   Java	Memory (MB): 512 Handler: com.demo.TriggerTests.apigTest Execution Timeout (s): 15
   Node.js	Memory (MB): 128 Handler: index.handler Execution Timeout (s): 3
   Custom	Memory (MB): 128 Handler: bootstrap Execution Timeout (s): 3
   Python	Memory (MB): 128 Handler: index.handler Execution Timeout (s): 3
   Go 1.x	Memory (MB): 128 Handler: handler Execution Timeout (s): 3