Woocommerce REST API add to cart

Adding Products to Cart Using WooCommerce REST API

The WooCommerce REST API provides a powerful way to interact with your online store's data programmatically. One of the common requirements for developers is to add products to the cart using the API. This article will guide you through the process with code samples and detailed explanations.

Prerequisites

Before we begin, ensure you have the following:

• A WooCommerce store set up.
• REST API credentials (Consumer Key and Consumer Secret) from your WooCommerce store.
• Basic understanding of HTTP requests and JSON.

Getting Started with WooCommerce REST API

Setting Up API Credentials

First, you need to generate API keys from your WooCommerce store:

1. Navigate to WooCommerce > Settings > Advanced > REST API.
2. Click "Add Key".
3. Fill in the description, choose a user with read/write access, and set the permission to "Read/Write".
4. Click "Generate API Key".

Save the Consumer Key and Consumer Secret provided.

API Client Setup

To interact with the WooCommerce REST API, we'll use an HTTP client. For this example, we'll use axios in a Node.js environment.

Install axios via npm:

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npm install axios

Base Setup

Create a basic setup for making API requests:

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const axios = require('axios');

const consumerKey = 'ck_your_consumer_key';
const consumerSecret = 'cs_your_consumer_secret';

const instance = axios.create({
  baseURL: 'https://your-woocommerce-site.com/wp-json/wc/v3/',
  auth: {
    username: consumerKey,
    password: consumerSecret
  }
});

instance.interceptors.request.use(request => {
  console.log('Starting Request', request);
  return request;
});

instance.interceptors.response.use(response => {
  console.log('Response:', response);
  return response;
});

module.exports = instance;

Adding a Product to Cart

Step 1: Retrieve Cart Information

First, we need to retrieve the current cart information. This is useful to ensure the cart exists and to get the cart's contents.

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const getCart = async () => {
  try {
    const response = await instance.get('cart');
    console.log('Cart:', response.data);
  } catch (error) {
    console.error('Error fetching cart:', error);
  }
};

getCart();

Step 2: Add Product to Cart

To add a product to the cart, we'll send a POST request to the /cart/add endpoint with the product ID and quantity.

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const addToCart = async (productId, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity
    });
    console.log('Product added to cart:', response.data);
  } catch (error) {
    console.error('Error adding product to cart:', error);
  }
};

// Example usage:
addToCart(123);  // Replace 123 with your product ID

Step 3: Verify Cart Contents

After adding the product, you can verify the cart contents by fetching the cart again:

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const getCartContents = async () => {
  try {
    const response = await instance.get('cart');
    console.log('Updated Cart:', response.data);
  } catch (error) {
    console.error('Error fetching updated cart:', error);
  }
};

getCartContents();

Handling Errors

It's important to handle errors that may occur during the API requests. Here is an example of improved error handling:

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const addToCart = async (productId, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity
    });
    console.log('Product added to cart:', response.data);
  } catch (error) {
    if (error.response) {
      // The request was made and the server responded with a status code
      // that falls out of the range of 2xx
      console.error('Error response data:', error.response.data);
      console.error('Error response status:', error.response.status);
      console.error('Error response headers:', error.response.headers);
    } else if (error.request) {
      // The request was made but no response was received
      console.error('Error request data:', error.request);
    } else {
      // Something happened in setting up the request that triggered an Error
      console.error('Error message:', error.message);
    }
    console.error('Error config:', error.config);
  }
};

Full Example

Here's the full example combining all the steps:

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const axios = require('axios');

const consumerKey = 'ck_your_consumer_key';
const consumerSecret = 'cs_your_consumer_secret';

const instance = axios.create({
  baseURL: 'https://your-woocommerce-site.com/wp-json/wc/v3/',
  auth: {
    username: consumerKey,
    password: consumerSecret
  }
});

instance.interceptors.request.use(request => {
  console.log('Starting Request', request);
  return request;
});

instance.interceptors.response.use(response => {
  console.log('Response:', response);
  return response;
});

const getCart = async () => {
  try {
    const response = await instance.get('cart');
    console.log('Cart:', response.data);
  } catch (error) {
    console.error('Error fetching cart:', error);
  }
};

const addToCart = async (productId, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity
    });
    console.log('Product added to cart:', response.data);
  } catch (error) {
    if (error.response) {
      console.error('Error response data:', error.response.data);
      console.error('Error response status:', error.response.status);
      console.error('Error response headers:', error.response.headers);
    } else if (error.request) {
      console.error('Error request data:', error.request);
    } else {
      console.error('Error message:', error.message);
    }
    console.error('Error config:', error.config);
  }
};

const getCartContents = async () => {
  try {
    const response = await instance.get('cart');
    console.log('Updated Cart:', response.data);
  } catch (error) {
    console.error('Error fetching updated cart:', error);
  }
};

// Example usage:
(async () => {
  await getCart();
  await addToCart(123);  // Replace 123 with your product ID
  await getCartContents();
})();

Adding products to a cart using the WooCommerce REST API involves making a few HTTP requests to retrieve the cart, add items, and verify the contents. By understanding how to make these requests and handle potential errors, you can create a seamless experience for your customers and efficiently manage the cart programmatically.

There are several advanced scenarios and edge cases when dealing with adding products to the cart via the WooCommerce REST API. These can include:

1. Adding variable products to the cart.
2. Managing inventory and checking stock before adding items to the cart.
3. Handling custom product fields.
4. Adding multiple products at once.
5. Handling different user sessions.

Let's dive into each case with detailed explanations and code samples.

1. Adding Variable Products to the Cart

Variable products have variations (e.g., different sizes, colors). To add a variable product to the cart, you need to specify the variation ID instead of the product ID.

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const addToCartVariableProduct = async (productId, variationId, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      variation_id: variationId,
      quantity: quantity
    });
    console.log('Variable product added to cart:', response.data);
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
addToCartVariableProduct(123, 456); // Replace with your product and variation IDs

2. Managing Inventory and Checking Stock

Before adding a product to the cart, you might want to check if the product is in stock.

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const checkStockAndAddToCart = async (productId, quantity = 1) => {
  try {
    const productResponse = await instance.get(`products/${productId}`);
    const product = productResponse.data;

    if (product.stock_status === 'instock' && product.stock_quantity >= quantity) {
      await addToCart(productId, quantity);
    } else {
      console.error('Product is out of stock or insufficient quantity available.');
    }
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
checkStockAndAddToCart(123, 2); // Replace 123 with your product ID

3. Handling Custom Product Fields

If your products have custom fields that need to be considered when adding to the cart, include them in the request.

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const addToCartWithCustomFields = async (productId, customFields, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity,
      custom_fields: customFields // Assuming your WooCommerce setup can handle this
    });
    console.log('Product with custom fields added to cart:', response.data);
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
addToCartWithCustomFields(123, { gift_wrap: true, message: "Happy Birthday!" });

4. Adding Multiple Products at Once

To add multiple products to the cart in one API call, you can iterate over an array of products.

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const addMultipleProductsToCart = async (products) => {
  try {
    for (const product of products) {
      await instance.post('cart/add', {
        id: product.id,
        quantity: product.quantity
      });
    }
    console.log('Multiple products added to cart.');
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
addMultipleProductsToCart([
  { id: 123, quantity: 1 },
  { id: 456, quantity: 2 }
]);

5. Handling Different User Sessions

To handle different user sessions, you need to manage session tokens or cookies that identify unique users. Here’s an example using a session token:

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const axios = require('axios');

const consumerKey = 'ck_your_consumer_key';
const consumerSecret = 'cs_your_consumer_secret';

const createInstanceForSession = (sessionToken) => {
  return axios.create({
    baseURL: 'https://your-woocommerce-site.com/wp-json/wc/v3/',
    headers: { 'X-WC-Session': sessionToken },
    auth: {
      username: consumerKey,
      password: consumerSecret
    }
  });
};

const addToCartForSession = async (sessionToken, productId, quantity = 1) => {
  const instance = createInstanceForSession(sessionToken);
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity
    });
    console.log('Product added to cart for session:', response.data);
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
const sessionToken = 'your_session_token'; // Get this from your authentication flow
addToCartForSession(sessionToken, 123, 1);

Error Handling Function

Here's a reusable error handling function:

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const handleApiError = (error) => {
  if (error.response) {
    console.error('Error response data:', error.response.data);
    console.error('Error response status:', error.response.status);
    console.error('Error response headers:', error.response.headers);
  } else if (error.request) {
    console.error('Error request data:', error.request);
  } else {
    console.error('Error message:', error.message);
  }
  console.error('Error config:', error.config);
};

Handling advanced cases and edge scenarios requires careful management of product variations, inventory checks, custom fields, bulk additions, and user sessions. By understanding these concepts and using the provided code snippets, you can build robust integrations with the WooCommerce REST API to manage your store's cart functionality programmatically.

When working with the WooCommerce REST API for adding products to the cart, you may encounter several common errors. Here are some typical errors and their solutions:

1. Authentication Errors

Error:

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{
  "code": "woocommerce_rest_authentication_error",
  "message": "Consumer key is invalid.",
  "data": {
    "status": 401
  }
}

Solution:

• Ensure that the Consumer Key and Consumer Secret are correct.
• Check if the API keys have the necessary permissions (Read/Write).
• Verify that the keys are not expired or revoked.

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const consumerKey = 'ck_correct_consumer_key';
const consumerSecret = 'cs_correct_consumer_secret';

2. Invalid Endpoint

Error:

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{
  "code": "rest_no_route",
  "message": "No route was found matching the URL and request method",
  "data": {
    "status": 404
  }
}

Solution:

• Verify the endpoint URL. The correct endpoint for adding to cart might be different based on your WooCommerce setup or customizations.

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const instance = axios.create({
  baseURL: 'https://your-woocommerce-site.com/wp-json/wc/v3/',
  auth: {
    username: consumerKey,
    password: consumerSecret
  }
});

3. Product Not Found

Error:

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{
  "code": "woocommerce_rest_product_invalid",
  "message": "Invalid product ID.",
  "data": {
    "status": 404
  }
}

Solution:

• Check if the product ID exists in your WooCommerce store.
• Ensure the product is published and not in a draft or trash state.

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const productId = 123; // Ensure this product ID exists

4. Out of Stock

Error:

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{
  "code": "woocommerce_rest_cart_product_out_of_stock",
  "message": "You cannot add that amount to the cart — we have 0 in stock and you already have 0 in your cart.",
  "data": {
    "status": 400
  }
}

Solution:

• Check the stock status of the product before adding to the cart.

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const checkStockAndAddToCart = async (productId, quantity = 1) => {
  try {
    const productResponse = await instance.get(`products/${productId}`);
    const product = productResponse.data;

    if (product.stock_status === 'instock' && product.stock_quantity >= quantity) {
      await addToCart(productId, quantity);
    } else {
      console.error('Product is out of stock or insufficient quantity available.');
    }
  } catch (error) {
    handleApiError(error);
  }
};

5. Invalid Variation

Error:

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{
  "code": "woocommerce_rest_invalid_product_variation",
  "message": "The specified product variation is invalid.",
  "data": {
    "status": 404
  }
}

Solution:

• Verify the variation ID and ensure it corresponds to the correct product ID.

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const addToCartVariableProduct = async (productId, variationId, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      variation_id: variationId,
      quantity: quantity
    });
    console.log('Variable product added to cart:', response.data);
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
addToCartVariableProduct(123, 456); // Ensure these IDs are correct

6. Session Management Issues

Error:

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{
  "code": "woocommerce_rest_cannot_view",
  "message": "Sorry, you cannot view this resource.",
  "data": {
    "status": 401
  }
}

Solution:

• Ensure that the session token or cookie is correctly managed and included in the request headers.

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const createInstanceForSession = (sessionToken) => {
  return axios.create({
    baseURL: 'https://your-woocommerce-site.com/wp-json/wc/v3/',
    headers: { 'X-WC-Session': sessionToken },
    auth: {
      username: consumerKey,
      password: consumerSecret
    }
  });
};

const addToCartForSession = async (sessionToken, productId, quantity = 1) => {
  const instance = createInstanceForSession(sessionToken);
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity
    });
    console.log('Product added to cart for session:', response.data);
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
const sessionToken = 'your_session_token'; // Get this from your authentication flow
addToCartForSession(sessionToken, 123, 1);

7. Custom Field Errors

Error:

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{
  "code": "woocommerce_rest_invalid_custom_field",
  "message": "The specified custom field is invalid.",
  "data": {
    "status": 400
  }
}

Solution:

• Ensure that the custom fields are correctly formatted and expected by your WooCommerce setup.

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const addToCartWithCustomFields = async (productId, customFields, quantity = 1) => {
  try {
    const response = await instance.post('cart/add', {
      id: productId,
      quantity: quantity,
      custom_fields: customFields // Assuming your WooCommerce setup can handle this
    });
    console.log('Product with custom fields added to cart:', response.data);
  } catch (error) {
    handleApiError(error);
  }
};

// Example usage:
addToCartWithCustomFields(123, { gift_wrap: true, message: "Happy Birthday!" });

Reusable Error Handling Function

A generic error handling function can be reused to simplify error management.

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const handleApiError = (error) => {
  if (error.response) {
    console.error('Error response data:', error.response.data);
    console.error('Error response status:', error.response.status);
    console.error('Error response headers:', error.response.headers);
  } else if (error.request) {
    console.error('Error request data:', error.request);
  } else {
    console.error('Error message:', error.message);
  }
  console.error('Error config:', error.config);
};

By understanding common errors and their solutions, you can better handle issues that arise when adding products to the cart using the WooCommerce REST API. Proper error handling, validation, and checks ensure a robust integration and improve user experience.