Fetch data

To invoke an endpoint, you need to set apiName, path and headers parameters, and each method returns a Promise. Under the hood the API category utilizes Axios to execute the HTTP requests. API status code response > 299 are thrown as an exception. If you need to handle errors managed by your API, work with the error.response object.

GET requests

1const apiName = 'MyApiName';
2const path = '/path';
3const myInit = {
4  headers: {}, // OPTIONAL
5  response: true, // OPTIONAL (return the entire Axios response object instead of only response.data)
6  queryStringParameters: {
7    name: 'param' // OPTIONAL
8  }
9};
10
11API.get(apiName, path, myInit)
12  .then((response) => {
13    // Add your code here
14  })
15  .catch((error) => {
16    console.log(error.response);
17  });

Example with async/await

1function getData() {
2  const apiName = 'MyApiName';
3  const path = '/path';
4  const myInit = {
5    headers: {} // OPTIONAL
6  };
7
8  return API.get(apiName, path, myInit);
9}
10
11(async function () {
12  const response = await getData();
13})();

GET requests with query parameters

To use query parameters with get method, you can pass them in queryStringParameters parameter in your method call:

1const items = await API.get('myCloudApi', '/items', {
2  queryStringParameters: {
3    order: 'byPrice'
4  }
5});

HEAD

1const apiName = 'MyApiName'; // replace this with your api name.
2const path = '/path'; //replace this with the path you have configured on your API
3const myInit = {
4  headers: {} // OPTIONAL
5};
6
7API.head(apiName, path, myInit).then((response) => {
8  // Add your code here
9});

Example with async/await:

1function head() {
2  const apiName = 'MyApiName';
3  const path = '/path';
4  const myInit = {
5    headers: {} // OPTIONAL
6  };
7
8  return API.head(apiName, path, myInit);
9}
10
11(async function () {
12  const response = await head();
13})();

Accessing query parameters & body in Lambda proxy function

To learn more about Lambda Proxy Integration, please visit Amazon API Gateway Developer Guide.

If you are using a REST API which is generated with Amplify CLI, your backend is created with Lambda Proxy Integration, and you can access your query parameters & body within your Lambda function via the event object:

1exports.handler = function (event, context, callback) {
2  console.log(event.queryStringParameters);
3  console.log('body: ', event.body);
4};

Alternatively, you can update your backend file which is located at amplify/backend/function/[your-lambda-function]/app.js with the middleware:

1const awsServerlessExpressMiddleware = require('aws-serverless-express/middleware');
2app.use(awsServerlessExpressMiddleware.eventContext());

Accessing Query Parameters with Serverless Express

In your request handler use req.apiGateway.event or req.query:

1app.get('/items', function (req, res) {
2  const query = req.query;
3  // or
4  // const query = req.apiGateway.event.queryStringParameters
5  res.json({
6    event: req.apiGateway.event, // to view all event data
7    query: query
8  });
9});

Then you can use query parameters in your path as follows:

1API.get('sampleCloudApi', '/items?q=test');

Custom response types

By default, calling an API with AWS Amplify parses a JSON response. If you have a REST API endpoint which returns, for example, a file in Blob format, you can specify a custom response type using the responseType parameter in your method call:

1let file = await API.get('myCloudApi', '/items', {
2  responseType: 'blob'
3});

Allowed values for responseType are "arraybuffer", "blob", "document", "json" or "text"; and it defaults to "json" if not specified. See the documentation for more information.

Set up Amplify REST API

Update data