Fetch data

GET requests

To make a GET request, first build a RestOptions object and then use the Amplify.API.get api to issue the request:

1void getTodo() {
2    RestOptions options = RestOptions.builder()
3        .addPath("/todo")
4        .build();
5
6    Amplify.API.get(options,
7        restResponse -> Log.i("MyAmplifyApp", "GET succeeded: " + restResponse),
8        apiFailure -> Log.e("MyAmplifyApp", "GET failed.", apiFailure)
9    );
10}

1private fun getTodo() {
2    val request = RestOptions.builder()
3        .addPath("/todo")
4        .build()
5
6    Amplify.API.get(request,
7        { Log.i("MyAmplifyApp", "GET succeeded: $it") },
8        { Log.e("MyAmplifyApp", "GET failed.", it) }
9    )
10}

1private suspend fun getTodo() {
2    val request = RestOptions.builder()
3        .addPath("/todo")
4        .build()
5
6    try {
7        val response = Amplify.API.get(request)
8        Log.i("MyAmplifyApp", "GET succeeded: ${response.data}")
9    } catch (error: ApiException) {
10        Log.e("MyAmplifyApp", "GET failed", error)
11    }
12}

1void getTodo() {
2    RestOptions options = RestOptions.builder()
3        .addPath("/todo")
4        .build();
5
6    RxAmplify.API.get(options)
7        .subscribe(
8            restResponse -> Log.i("MyAmplifyApp", "GET succeeded: " + restResponse),
9            apiFailure -> Log.e("MyAmplifyApp", "GET failed.", apiFailure)
10        );
11}

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('/todo', 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:

1RestOptions options = RestOptions.builder()
2    .addPath("/todo")
3    .addQueryParameters(Collections.singletonMap("q", "test"))
4    .build();
5
6Amplify.API.get(options,
7    response -> Log.i("MyAmplifyApp", "GET succeeded: " + response),
8    error -> Log.e("MyAmplifyApp", "GET failed.", error)
9);

1val request = RestOptions.builder()
2    .addPath("/todo")
3    .addQueryParameters(mapOf("q" to "test"))
4    .build()
5
6Amplify.API.get(request,
7    { Log.i("MyAmplifyApp", "GET succeeded: $it") },
8    { Log.e("MyAmplifyApp", "GET failed", it) }
9)

1val request = RestOptions.builder()
2    .addPath("/todo")
3    .addQueryParameters(mapOf("q" to "test"))
4    .build()
5
6try {
7    val response = Amplify.API.get(request)
8    Log.i("MyAmplifyApp", "GET succeeded: $response.")
9} catch (error: ApiException) {
10    Log.e("MyAmplifyApp", "GET failed", error)
11}

1RestOptions options = RestOptions.builder()
2    .addPath("/todo")
3    .addQueryParameters(Collections.singletonMap("q", "test"))
4    .build();
5
6RxAmplify.API.get(options)
7    .subscribe(
8        response -> Log.i("MyAmplifyApp", "GET succeeded: " + response),
9        error -> Log.e("MyAmplifyApp", "GET failed.", error)
10    );

Set up Amplify REST API

Update data