Cấu hình đa môi trường cho CDK app

				
					import * as cdk from "aws-cdk-lib";
// These values map to the keys in our cdk.json and make sure
// no values that aren't supported are passed in with the
// -c config=env flag
const supportedEnvironments = ["dev", "stg", "prod"] as const;

type SupportedEnvironments = typeof supportedEnvironments[number];

// This maps to the values you specified in your cdk.json file
// if you add any values to your cdk.json file, also add them here!
export type BuildConfig = {
  environment: SupportedEnvironments;
  projectOwner: string;
  projectName: string;
  costOwner: string;
};

// This function is used by your CDK app and pulls your config values
// from the context
export const getConfig = (app: cdk.App): BuildConfig => {
  const env = app.node.tryGetContext("config");
  if (!env) {
    throw new Error(
      "Environment variable must be passed to cdk: `yarn cdk -c config=XXX`"
    );
  }
  if (!supportedEnvironments.includes(env)) {
    throw new Error(
      `${env} is not in supported environments: ${supportedEnvironments.join(
        ", "
      )}`
    );
  }
  // this contains the values in the context without being
  // validated
  const unparsedEnv = app.node.tryGetContext(env);

  return {
    environment: env,
    projectOwner: ensureString(unparsedEnv, "projectOwner"),
    projectName: ensureString(unparsedEnv, "projectName"),
    costOwner: ensureString(unparsedEnv, "costOwner"),
  };
};


// this function ensures that the value from the config is
// the correct type. If you have any types other than
// strings be sure to create a new validation function
function ensureString(
  object: { [name: string]: any },
  key: keyof BuildConfig
): string {
  if (
    !object[key] ||
    typeof object[key] !== "string" ||
    object[key].trim().length === 0
  ) {
    throw new Error(key + " does not exist in cdk config");
  }
  return object[key];
}