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services:
  postgres:
    image: postgres:14.1-alpine
    restart: always
    environment:
      # You can set the value of environment variables
      # in your docker-compose.yml file
      # Our Node app will use these to connect
      # to the database
      - POSTGRES_USER=root

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-- Create database
CREATE DATABASE "RENTALS";

CREATE TABLE CUSTOMER (
  CID SERIAL PRIMARY KEY,
  name TEXT NOT NULL,
  address TEXT NOT NULL,
  phone TEXT NOT NULL
);

adriangabardo

// Defining a searchBy method on an array
interface SearchFn<T> {
  (key: string, value: string): { index: number; value: T }[] | undefined;
}

// Extend the Array interface to include a searchBy method
interface SearchableArray<T> extends Array<T> {
  searchBy: SearchFn<T>;
}

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/**
 * A utility method to safely extract environment variables.
 * By default, if an environment variable is asked to be extracted but it is missing, this method will throw an error.
 * @param options - Additional options for this method's behaviour, including deciding if it should throw when a variable is missing.
 * @param environmentVariables - A spread of environment variable keys to be fetched from process.env.
 * @returns A new object with each environmentVariables key in it. Unless throwOnError is false, all environmentVariables params will be present.
 */
export const extract_environment_variables = <T extends string[]>(
  { throwOnError = true }: { throwOnError?: boolean },
  ...environmentVariables: T

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/**
 * Type alias to recursively make all properties of an object optionally undefined or null.
 * Adds | undefined | null to all objects and its properties.
 */
type DeepNullable<T> = T extends object
  ? { [k in keyof T]?: DeepNullable<T[k] | null> }
  : T | null;

interface TestObj {
  nothing: boolean;

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/**
 * Example of a higher-order component with type-safety for functions with generic spread variables.
 * In this example, the HOC is a function to create AWS Lambda (for AWS API Gateway) function handlers.
 * All AWS Lambda exported handlers receive an (event, context) set of parameters.
 *
 * @author Adrian Gabardo <[email protected]>
 */

type LambdaResponse = Promise<any | void>;
type BaseLambda = (event, context) => LambdaResponse;