Configure the logging feature

Prerequisites

• Function Compute

  • Create a function

• Optional: Simple Log Service (SLS)

  • Create a project and Logstore

Procedure

1. Log on to the Function Compute console. In the left-side navigation pane, click Functions.

2. In the top navigation bar, select a region. On the Functions page, click the function that you want to manage.

3. On the function details page, select the Configuration tab, click Advanced Settings to the right of Advanced Settings, locate the Logs option in the Advanced Settings panel, complete the log configuration by performing the following steps, and then click Deploy.

   Note

   • When you create a function, the logging feature is enabled by default, and the system automatically selects the Log Service Project that starts with serverless-<region_id> and the default Logstore.

   • The console automatically enables Log Rotation Rules, Request-level Metrics, and Instance-level Metrics, and creates all required indexes for log queries.

   Configuration item	Required	Description
   Logging	Yes	Specifies whether to enable Simple Log Service. Valid values: Enable: After you enable this feature, Function Compute imports logs into your log project. You can query and retrieve logs in the Function Compute console and the Simple Log Service console to troubleshoot and identify issues. Disable: Logging is disabled. Function logs cannot be persisted, and you cannot trace or locate issues.
   Configuration Mode	Yes	Select Automatic Configuration or Custom Configuration. If you select Custom Configuration, you must specify a Log Service Project and Logstore.
   Log Service Project	Yes	Specifies the target project for storing function invocation logs.
   Logstore	Yes	Specifies the target Logstore for storing function invocation logs.
   Log Rotation Rules	No	Specifies whether to enable log segmentation rules. Valid values: Enable: When enabled, Function Compute will split logs according to log segmentation rules into multiple log segments and write them individually to Simple Log Service. The default rule is ^.{0,2}\d{4}-\d{2}-\d{2}, which matches dates in the format xxxx-xx-xx, where x is a digit. Logs are split based on whether a line starts with a date. For example, if a log line starts with "2023-10-10", it is treated as the first line of a new log block. This line and subsequent lines without a leading date are written as one log entry. Disable: Log segmentation is disabled. Logs are split using the default delimiter \n .
   Request-level Metrics	No	Specifies whether to import request metric logs into the Logstore. We strongly recommend enabling this feature. Valid values: Enable: Metrics for each function invocation—such as execution time, memory usage, error status, cold start occurrence, and cold start step durations—are delivered to the Logstore you selected during logging configuration. The Function Compute invocation logs display a request list based on these metrics. You can also filter requests by metrics, such as all error requests or requests with cold starts. Disable: You cannot view detailed request execution information.
   Instance-level Metrics	No	Specifies whether to enable instance-level metrics. Valid values: Enable: When enabled, metric data from function instances is delivered to the Logstore you selected during log configuration. You can view performance metrics at the function instance level, such as CPU, memory, and network I/O usage. Function Compute uses instance-level metric data to provide observability at the instance granularity, giving you an end-to-end monitoring and troubleshooting path for function instances. For more information, see Instance-Level Metrics. Disable: You cannot view detailed instance metrics.

Prerequisites

Install and configure Serverless Devs

Procedure

1. Create a code directory with the following structure.

   .
   ├── code
   │   └── index.js
   └── s.yaml

   In the example, the logConfig field configures logging. Replace logstore and project with an existing Logstore and project in your account. Alternatively, set logConfig: auto to let Function Compute automatically assign a project and Logstore.

   edition: 3.0.0
   name: hello-world-app
   access: "default"
   vars: # Global variables
     region: "cn-hangzhou"
   resources:
     hello_world:
       component: fc3 # Component name
       props:
         region: ${vars.region}             
         functionName: "start-nodejs-****"
         description: 'hello world by serverless devs'
         runtime: "nodejs16"
         code: ./code
         handler: index.handler
         memorySize: 128
         timeout: 30
         logConfig: # Replace logstore and project with actual values, or use logConfig: auto to auto-create project and Logstore
           enableInstanceMetrics: true  # Enable instance-level metrics
           enableRequestMetrics:  true  # Enable request-level metrics 
           logBeginRule: DefaultRegex   # Log segmentation rule
           logstore: 'your-logstore'    # Specify Logstore name (must exist)
           project: 'your-project'      # Specify project name (must exist)

2. Run the following command to deploy the application.

   sudo s deploy -y

   After successful deployment, log on to the Function Compute console to verify that the function is deployed and logging is enabled.