# DynamoDbDataSource

An AppSync datasource backed by a DynamoDB table.

Extends: Construct › BaseDataSource › BackedDataSource › DynamoDbDataSource
Implements: IGrantable, IConstruct, IDependable

- Source: [`aws-appsync/lib/data-source.ts`](https://github.com/aws/aws-cdk/blob/v2.274.0/packages/aws-cdk-lib/aws-appsync/lib/data-source.ts#L268)
- Type last changed: v2.196.0 · 16 May 2025

## Example

```ts
const api = new appsync.GraphqlApi(this, 'Api', {
  name: 'demo',
  definition: appsync.Definition.fromFile(path.join(__dirname, 'schema.graphql')),
  authorizationConfig: {
    defaultAuthorization: {
      authorizationType: appsync.AuthorizationType.IAM,
    },
  },
  xrayEnabled: true,
});

const demoTable = new dynamodb.Table(this, 'DemoTable', {
  partitionKey: {
    name: 'id',
    type: dynamodb.AttributeType.STRING,
  },
});

const demoDS = api.addDynamoDbDataSource('demoDataSource', demoTable);

// Resolver for the Query "getDemos" that scans the DynamoDb table and returns the entire list.
// Resolver Mapping Template Reference:
// https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-dynamodb.html
demoDS.createResolver('QueryGetDemosResolver', {
  typeName: 'Query',
  fieldName: 'getDemos',
  requestMappingTemplate: appsync.MappingTemplate.dynamoDbScanTable(),
  responseMappingTemplate: appsync.MappingTemplate.dynamoDbResultList(),
});

// Resolver for the Mutation "addDemo" that puts the item into the DynamoDb table.
demoDS.createResolver('MutationAddDemoResolver', {
  typeName: 'Mutation',
  fieldName: 'addDemo',
  requestMappingTemplate: appsync.MappingTemplate.dynamoDbPutItem(
    appsync.PrimaryKey.partition('id').auto(),
    appsync.Values.projecting('input'),
  ),
  responseMappingTemplate: appsync.MappingTemplate.dynamoDbResultItem(),
});

//To enable DynamoDB read consistency with the `MappingTemplate`:
demoDS.createResolver('QueryGetDemosConsistentResolver', {
  typeName: 'Query',
  fieldName: 'getDemosConsistent',
  requestMappingTemplate: appsync.MappingTemplate.dynamoDbScanTable(true),
  responseMappingTemplate: appsync.MappingTemplate.dynamoDbResultList(),
});
```

## Initializer

```ts
new DynamoDbDataSource(scope: Construct, id: string, props: DynamoDbDataSourceProps)
```

## Construct Props

- `api`: [IGraphQLApiRef](/cdk/api/v2/docs/aws-cdk-lib.interfaces.aws_appsync.IGraphQLApiRef.html) (required) — The API to attach this data source to.

- `description`: string = None — the description of the data source.

- `metricsConfig`: [DataSourceMetricsConfig](/cdk/api/v2/docs/aws-cdk-lib.aws_appsync.DataSourceMetricsConfig.html) — Whether to enable enhanced metrics of the data source Value will be ignored, if `enhancedMetricsConfig.dataSourceLevelMetricsBehavior` on AppSync GraphqlApi construct is set to `FULL_REQUEST_DATA_SOURCE_METRICS`.

  **Default:** no metrics configuration

- `name`: string — The name of the data source.

  **Default:** id of data source

- `readOnlyAccess`: boolean = false — Specify whether this DS is read only or has read and write permissions to the DynamoDB table.

- `serviceRole`: [IRole](/cdk/api/v2/docs/aws-cdk-lib.aws_iam.IRole.html) — The IAM service role to be assumed by AppSync to interact with the data source.

  **Default:** Create a new role

- `table`: [ITable](/cdk/api/v2/docs/aws-cdk-lib.aws_dynamodb.ITable.html) (required) — The DynamoDB table backing this data source.

- `useCallerCredentials`: boolean = false — use credentials of caller to access DynamoDB.

## Properties

- `ds`: [CfnDataSource](/cdk/api/v2/docs/aws-cdk-lib.aws_appsync.CfnDataSource.html) (required) — the underlying CFN data source resource.

- `grantPrincipal`: [IPrincipal](/cdk/api/v2/docs/aws-cdk-lib.aws_iam.IPrincipal.html) (required) — the principal of the data source to be IGrantable.

- `name`: string (required) — the name of the data source.

- `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) (required) — The tree node.

- `PROPERTY_INJECTION_ID`: string (required) (static) — Uniquely identifies this class.

## Methods

- `createFunction(id: string, props: BaseAppsyncFunctionProps): AppsyncFunction` — creates a new appsync function for this datasource and API using the given properties.

- `createResolver(id: string, props: BaseResolverProps): Resolver` — creates a new resolver for this datasource and API using the given properties.

- `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct.

  Use this method instead of `instanceof` to properly detect `Construct`
  instances, even when the construct library is symlinked.

  Explanation: in JavaScript, multiple copies of the `constructs` library on
  disk are seen as independent, completely different libraries. As a
  consequence, the class `Construct` in each copy of the `constructs` library
  is seen as a different class, and an instance of one class will not test as
  `instanceof` the other class. `npm install` will not create installations
  like this, but users may manually symlink construct libraries together or
  use a monorepo tool: in those cases, multiple copies of the `constructs`
  library can be accidentally installed, and `instanceof` will behave
  unpredictably. It is safest to avoid using `instanceof`, and using
  this type-testing method instead.

  **Parameters**

  - `x` — Any object.

  **Returns:** true if `x` is an object created from a class which extends `Construct`.

- `toString(): string` — Returns a string representation of this construct.

- `with(...mixins: IMixin[]): IConstruct` — Applies one or more mixins to this construct.

  Mixins are applied in order. The list of constructs is captured at the
  start of the call, so constructs added by a mixin will not be visited.
  Use multiple `with()` calls if subsequent mixins should apply to added
  constructs.

  **Parameters**

  - `mixins` — The mixins to apply.

  **Returns:** This construct for chaining