@aws-lambda-powertools/parameters
Version:
The parameters package for the Powertools for AWS Lambda (TypeScript) library
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JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.getParameter = void 0;
const DefaultProviders_js_1 = require("../base/DefaultProviders.js");
const SSMProvider_js_1 = require("./SSMProvider.js");
/**
* ## Intro
* The Parameters utility provides an SSMProvider that allows to retrieve parameters from AWS Systems Manager.
*
* ## Getting started
*
* This utility supports AWS SDK v3 for JavaScript only. This allows the utility to be modular, and you to install only
* the SDK packages you need and keep your bundle size small.
*
* To use the provider, you must install the Parameters utility and the AWS SDK v3 for JavaScript for AppConfig:
*
* ```sh
* npm install @aws-lambda-powertools/parameters @aws-sdk/client-ssm
* ```
*
* ## Basic usage
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a parameter
* const parameter = await getParameter('/my-parameter');
* };
* ```
*
* ## Advanced usage
*
* ### Decryption
*
* If you have encrypted parameters, you can use the `decrypt` option to automatically decrypt them.
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a parameter and decrypt it
* const parameter = await getParameter('/my-parameter', { decrypt: true });
* };
* ```
*
* ### Caching
*
* By default, the provider will cache parameters retrieved in-memory for 5 seconds.
* You can adjust how long values should be kept in cache by using the `maxAge` parameter.
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a parameter and cache it for 10 seconds
* const parameter = await getParameter('/my-parameter', { maxAge: 10 });
* };
* ```
*
* If instead you'd like to always ensure you fetch the latest parameter from the store regardless if already available in cache, use the `forceFetch` parameter.
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a parameter and always fetch the latest value
* const parameter = await getParameter('/my-parameter', { forceFetch: true });
* };
* ```
*
* ### Transformations
*
* For parameters stored as JSON you can use the transform argument for deserialization. This will return a JavaScript object instead of a string.
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a parameter and parse it as JSON
* const parameter = await getParameter('/my-parameter', { transform: 'json' });
* };
* ```
*
* For parameters that are instead stored as base64-encoded binary data, you can use the transform argument set to `binary` for decoding. This will return a decoded string.
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a base64-encoded string and decode it
* const parameter = await getParameter('/my-parameter', { transform: 'binary' });
* };
* ```
*
* ### Extra SDK options
*
* When retrieving a parameter, you can pass extra options to the AWS SDK v3 for JavaScript client by using the `sdkOptions` parameter.
*
* @example
* ```typescript
* import { getParameter } from '@aws-lambda-powertools/parameters/ssm';
*
* export const handler = async (): Promise<void> => {
* // Retrieve a parameter and pass extra options to the AWS SDK v3 for JavaScript client
* const parameter = await getParameter('/my-parameter', {
* sdkOptions: {
* WithDecryption: true,
* },
* });
* };
* ```
*
* This object accepts the same options as the [AWS SDK v3 for JavaScript SSM GetParameter command](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/clients/client-ssm/interfaces/getparametercommandinput.html).
*
* ### Built-in provider class
*
* For greater flexibility such as configuring the underlying SDK client used by built-in providers, you can use the {@link SSMProvider} class.
*
* ### Options
*
* * You can customize the retrieval of the value by passing options to the function:
* * `maxAge` - The maximum age of the value in cache before fetching a new one (in seconds) (default: 5)
* * `forceFetch` - Whether to always fetch a new value from the store regardless if already available in cache
* * `transform` - Whether to transform the value before returning it. Supported values: `json`, `binary`
* * `sdkOptions` - Extra options to pass to the AWS SDK v3 for JavaScript client
* * `decrypt` - Whether to decrypt the value before returning it.
*
* For more usage examples, see [our documentation](https://docs.powertools.aws.dev/lambda/typescript/latest/utilities/parameters/).
*
* @param {string} name - The name of the parameter to retrieve
* @param {SSMGetOptions} options - Options to configure the provider
* @see https://docs.powertools.aws.dev/lambda/typescript/latest/utilities/parameters/
*/
const getParameter = async (name, options) => {
if (!Object.hasOwn(DefaultProviders_js_1.DEFAULT_PROVIDERS, 'ssm')) {
DefaultProviders_js_1.DEFAULT_PROVIDERS.ssm = new SSMProvider_js_1.SSMProvider();
}
return DefaultProviders_js_1.DEFAULT_PROVIDERS.ssm.get(name, options);
};
exports.getParameter = getParameter;