Learn IBM-CLOUD-FUNCTIONS with Real Code Examples

Updated Nov 25, 2025

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Code Sample Descriptions

Simple IBM Cloud Function (Node.js)

# ibm_cloud/demo/hello.js
function main(params) {
    return { body: 'Hello, IBM Cloud!' };
}
exports.main = main;

A simple IBM Cloud Function that returns 'Hello, IBM Cloud!' when invoked.

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IBM Cloud Function with Parameters

# ibm_cloud/demo/params.js
function main(params) {
    const name = params.name || 'Guest';
    return { body: `Hello, ${name}!` };
}
exports.main = main;

A Cloud Function that greets a user based on input parameters.

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IBM Cloud Function Returning JSON

# ibm_cloud/demo/json.js
function main(params) {
    return { body: { message: 'Hello JSON!' } };
}
exports.main = main;

A function returning a JSON object.

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IBM Cloud Function Handling HTTP Method

# ibm_cloud/demo/method.js
function main(params) {
    const method = params.__ow_method;
    if (method === 'POST') {
        return { body: 'You sent a POST request' };
    }
    return { body: 'You sent a GET request' };
}
exports.main = main;

A function responding differently based on HTTP method.

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IBM Cloud Function Using Environment Variable

# ibm_cloud/demo/env.js
function main(params) {
    const apiKey = process.env.MY_API_KEY || 'NotSet';
    return { body: `API Key length: ${apiKey.length}` };
}
exports.main = main;

A function accessing an environment variable.

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IBM Cloud Function Redirect

# ibm_cloud/demo/redirect.js
function main(params) {
    return {
        statusCode: 302,
        headers: { Location: 'https://example.com' },
        body: ''
    };
}
exports.main = main;

A function that responds with a redirect.

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IBM Cloud Function with Custom Headers

# ibm_cloud/demo/headers.js
function main(params) {
    return {
        statusCode: 200,
        headers: { 'X-Custom-Header': 'IBMCloudFunction' },
        body: 'Custom headers added'
    };
}
exports.main = main;

A function adding custom headers to the response.

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IBM Cloud Function Fetching External API

# ibm_cloud/demo/fetch.js
const fetch = require('node-fetch');
async function main(params) {
    const response = await fetch('https://api.github.com');
    const data = await response.json();
    return { body: data };
}
exports.main = main;

A function fetching data from an external API and returning it.

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IBM Cloud Function Serving HTML

# ibm_cloud/demo/html.js
function main(params) {
    const html = '<!DOCTYPE html><html><body><h1>Hello HTML!</h1></body></html>';
    return {
        statusCode: 200,
        headers: { 'Content-Type': 'text/html' },
        body: html
    };
}
exports.main = main;

A function responding with a simple HTML page.

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IBM Cloud Function Conditional Response

# ibm_cloud/demo/conditional.js
function main(params) {
    if (params.action === 'ping') {
        return { body: 'pong' };
    }
    return { body: 'unknown action' };
}
exports.main = main;

A function responding differently based on query parameter.

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Code Sample Descriptions

Simple IBM Cloud Function (Node.js)

# ibm_cloud/demo/hello.js
function main(params) {
    return { body: 'Hello, IBM Cloud!' };
}
exports.main = main;

A simple IBM Cloud Function that returns 'Hello, IBM Cloud!' when invoked.

Let’s Try →

IBM Cloud Function with Parameters

# ibm_cloud/demo/params.js
function main(params) {
    const name = params.name || 'Guest';
    return { body: `Hello, ${name}!` };
}
exports.main = main;

A Cloud Function that greets a user based on input parameters.

Let’s Try →

IBM Cloud Function Returning JSON

# ibm_cloud/demo/json.js
function main(params) {
    return { body: { message: 'Hello JSON!' } };
}
exports.main = main;

A function returning a JSON object.

Let’s Try →

IBM Cloud Function Handling HTTP Method

# ibm_cloud/demo/method.js
function main(params) {
    const method = params.__ow_method;
    if (method === 'POST') {
        return { body: 'You sent a POST request' };
    }
    return { body: 'You sent a GET request' };
}
exports.main = main;

A function responding differently based on HTTP method.

Let’s Try →

IBM Cloud Function Using Environment Variable

# ibm_cloud/demo/env.js
function main(params) {
    const apiKey = process.env.MY_API_KEY || 'NotSet';
    return { body: `API Key length: ${apiKey.length}` };
}
exports.main = main;

A function accessing an environment variable.

Let’s Try →

IBM Cloud Function Redirect

# ibm_cloud/demo/redirect.js
function main(params) {
    return {
        statusCode: 302,
        headers: { Location: 'https://example.com' },
        body: ''
    };
}
exports.main = main;

A function that responds with a redirect.

Let’s Try →

IBM Cloud Function with Custom Headers

# ibm_cloud/demo/headers.js
function main(params) {
    return {
        statusCode: 200,
        headers: { 'X-Custom-Header': 'IBMCloudFunction' },
        body: 'Custom headers added'
    };
}
exports.main = main;

A function adding custom headers to the response.

Let’s Try →

IBM Cloud Function Fetching External API

# ibm_cloud/demo/fetch.js
const fetch = require('node-fetch');
async function main(params) {
    const response = await fetch('https://api.github.com');
    const data = await response.json();
    return { body: data };
}
exports.main = main;

A function fetching data from an external API and returning it.

Let’s Try →

IBM Cloud Function Serving HTML

# ibm_cloud/demo/html.js
function main(params) {
    const html = '<!DOCTYPE html><html><body><h1>Hello HTML!</h1></body></html>';
    return {
        statusCode: 200,
        headers: { 'Content-Type': 'text/html' },
        body: html
    };
}
exports.main = main;

A function responding with a simple HTML page.

Let’s Try →

IBM Cloud Function Conditional Response

# ibm_cloud/demo/conditional.js
function main(params) {
    if (params.action === 'ping') {
        return { body: 'pong' };
    }
    return { body: 'unknown action' };
}
exports.main = main;

A function responding differently based on query parameter.

Let’s Try →