Module paginate

A helper function for getting paginated results from AWS API calls. Most APIs return a maximum number of results, and a pagination token to allow to you make another call for the next set of results until no results remain. Additionally many APIs use different parameters for the pagination token such as nextToken or NextToken. This function allows us to make a generic API call, defining the correct pagination token for the API call, and retrieving all of the results

const AWS = require('aws-sdk');
const client = new AWS.<client name>({<params>})();          // e.g. Organizations
const operation = '<operation name>'                         // e.g. listAccounts
paginationSettings = {
  inputToken: <the inputToken for the Operation>,            // e.g. NextToken
  outputToken: <the outputToken for the Operation>,          // e.g. NextToken
  resultKey: <the resultKey for the Operation>,              // e.g. Accounts
  moreResults: <Optional moreResults key for the Operation>, // e.g. IsTruncated
}
const res = await getPaginatedResults(async (paginationTokenValueForRequest) => {
  const operationParams = Object.assign({ [paginationSettings.inputToken]: paginationTokenValueForRequest }, params);
  //console.log(`Paginating\n\tclient: ${client.api.serviceId}\n\toperation: ${operation}\n\tparams: ${JSON.stringify(operationParams, null, 2)}\n\tpaginationSettings: ${JSON.stringify(paginationSettings, null, 2)}`);
  const page = await client[operation](operationParams).promise();

  return {
    paginationTokenValueFromResultsPage: page[paginationSettings.outputToken],
    resultsFromPage: page[paginationSettings.resultKey],
    moreResults: paginationSettings.moreResults ? page[paginationSettings.moreResults] : undefined,
  };
});
return { [paginationSettings.resultKey]: res };

A function to make use of getPaginatedResults in a simple to use and standardised way. It accepts a configuration containing the AWS API Service and Operation to call, as well as optionally custom operation parameters, and custom pagination settings and tries to return paginated results for the call, either using the settings provided or automatically via information ascertained from the AWS API; or unpaginated if instructed or unable.

const aws = require('aws-sdk');
const paginationConfig = {
  client: new aws.<aws service>(<{params}>), // e.g. Route53
  operation: '<operation>',                  // e.g. listHostedZones
  paginationSettings: {
    inputToken: '<operation input token>',   // e.g. NextToken
    outputToken: '<operation output token>', // e.g. NextToken
    resultKey: '<operation result key>',     // e.g. HostedZones
  },
};
const results = await paginate(paginationConfig);
console.log(JSON.stringify(results, null, 2));