tcb fn run

Run and debug cloud functions locally without deploying them.

Node.js only

tcb fn run currently supports only the Node.js runtime. To run function-type CloudRun services locally, see CloudRun local run.

Usage

tcb fn run [options]

Two ways to locate a function:

• --path: point to the function directory and run with default configuration. No cloudbaserc.json required.
• --name: read the matching function configuration from cloudbaserc.json (handler, envVariables, params) and run it.

Flags

Flag	Required	Description	Default
--path <path>	One of --path or --name	Function directory, run with default configuration	—
--name <name>	One of --path or --name	Function name, configuration read from cloudbaserc.json	—
--params <params>	No	Invocation parameters as a JSON string	—
--debug	No	Start in Node Inspector mode	—
--port <port>	No	Debug listen port	9229

Examples

Run by path

The directory must contain index.js exporting a main method.

# Run ./functions/app with default configuration
tcb fn run --path ./functions/app

Run by name

The project directory must contain cloudbaserc.json with the function declared in functions.

tcb fn run --name app

The function runs with handler, envVariables, and params from the configuration file. See Function Configuration.

Pass parameters

tcb fn run --name app --params '{"userId": "123", "action": "query"}'

When both the configuration file and the command line set params, the command line wins.

Start debug mode

# Use the default port 9229
tcb fn run --path ./functions/app --debug

# Use a custom debug port
tcb fn run --path ./functions/app --debug --port 9230

Connect Chrome DevTools or VS Code to the port to set breakpoints.

Notes

• Only Node.js is supported. Python, Java, Go, PHP, and other runtimes cannot run locally through tcb fn run.
• With --path, the directory must contain index.js exporting a main method.
• With --name, the entry file and function name are resolved from handler in cloudbaserc.json, which defaults to index.main.
• When logged in, the runtime injects TENCENTCLOUD_SECRETID, TENCENTCLOUD_SECRETKEY, and TENCENTCLOUD_SESSIONTOKEN, so the function can call CloudBase resources directly. Without login these variables are absent and such calls may fail.