now-sync/util/add.js

A tool to help developers sync their JavaScript resources with ServiceNow.

const _ = require('lodash');
const fs = require('fs');
const mkdirp = require('mkdirp');
const path = require('path');
const Promise = require('bluebird');
const { parseConfigFile, saveConfigFile } = require('./config');
const {
  compileFileName,
  getFileNameFields,
  trimCwd
} = require('./file-naming');
const {
  convertServiceNowDatetimeToMoment,
  getRecord
} = require('./service-now');

const writeFileAsync = Promise.promisify(fs.writeFile);
const utimesAsync = Promise.promisify(fs.utimes);

/**
 * Creates a config entry and its local file to sync with a ServiceNow record.
 *
 * @param {string} table ServiceNow Table API Name
 * @param {string} sysId Table Record sys_id value
 */
async function add(table, sysId) {
  const config = parseConfigFile();
  const tableConfig = config.config[table];

  if (!tableConfig) {
    throw new Error(
      `Configuration for table \`${
        table
      }\` not found. Run \`now add:table\` to configure files for this table.`
    );
  }

  const data = await getFieldValues(table, sysId);
  const filesToWrite = generateFilesToWriteForRecord(table, data);
  return writeFilesForTable(table, filesToWrite);
}
exports.add = add;

/**
 * Creates an array of file data for a ServiceNow record.
 *
 * @param {string} table ServiceNow table’s API name
 * @param {object} fieldValues A field:value hash representing a ServiceNow record
 *
 * @typedef {object} fileContentObj
 * @property {string} contentField
 * @property {string} fileName
 * @property {string} fileContent
 *
 * @returns {fileContentObj[]} An array of file content objects
 */
function generateFilesToWriteForRecord(table, fieldValues) {
  const config = parseConfigFile();

  return _.map(
    config.config[table].formats,
    ({ fileName: fileTemplate, contentField }) => ({
      contentField,
      fileName: compileFileName(fileTemplate, fieldValues),
      fileContent: fieldValues[contentField],
      fileMtime: convertServiceNowDatetimeToMoment(
        fieldValues.sys_updated_on
      ).unix()
    })
  );
}
exports.generateFilesToWriteForRecord = generateFilesToWriteForRecord;

/**
 * Generates an array of field names to be used for syncing a table record to local files.
 *
 * @param {string} table ServiceNow table’s API Name
 * @returns {string[]} An array of the table’s field names
 */
function getFieldsToRetrieve(table) {
  const config = parseConfigFile();
  const recordFields = getFileNameFields(table);
  const contentFields = _.map(
    config.config[table].formats,
    ({ contentField }) => contentField
  );

  recordFields.push('sys_updated_on');

  const fieldsToRetrieve = _.uniq(recordFields.concat(contentFields));
  return _.map(fieldsToRetrieve, name => {
    if (name === 'sys_scope') {
      return 'sys_scope.scope';
    }

    if (name === 'web_service_definition') {
      return 'web_service_definition.service_id';
    }

    return name;
  });
}
exports.getFieldsToRetrieve = getFieldsToRetrieve;

/**
 * Retrieves the field values for a specific record from the ServiceNow instance.
 *
 * @param {string} table ServiceNow table’s API Name
 * @param {string} sysId The record sys_id
 * @returns {promise} Promise resolving to an object with the ServiceNow record’s field values
 */
function getFieldValues(table, sysId) {
  const fieldsToRetrieve = getFieldsToRetrieve(table);

  return getRecord(table, sysId, fieldsToRetrieve);
}
exports.getFieldValues = getFieldValues;

/**
 * Writes local files given a table name and file content.
 *
 * @typedef {object} fileContentObj
 * @property {string} contentField
 * @property {string} fileName
 * @property {string} fileContent
 *
 * @param {string} table ServiceNow table’s API Name
 * @param {fileContentObj[]} filesToWrite Generated by generateFilesToWriteForRecord()
 * @returns {Promise.<string[]>} A promise resolving to an array of file path strings written
 */
async function writeFilesForTable(table, filesToWrite) {
  const config = parseConfigFile();

  const writePath = path.resolve(process.cwd(), config.filePath, table);
  const writeFilePromises = [];
  const filesWritten = [];

  if (!fs.existsSync(writePath)) {
    mkdirp.sync(writePath);
  }
  if (!config.records[table]) {
    config.records[table] = [];
  }

  _.forEach(
    filesToWrite,
    ({ contentField, fileName, fileContent, fileMtime }) => {
      const filePath = path.resolve(writePath, fileName);
      const formattedFileContent = fileContent.replace(
        new RegExp('\r\n', 'g'), // eslint-disable-line no-control-regex
        '\n'
      );

      writeFilePromises.push(
        writeFileAsync(filePath, formattedFileContent)
          .then(() => utimesAsync(filePath, fileMtime, fileMtime))
          .then(() => {
            filesWritten.push(trimCwd(filePath));
          })
      );

      const recordConfigAlreadyExists = _.find(
        config.records[table],
        ({ fileName: configRecordFileName }) =>
          fileName === configRecordFileName
      );

      if (!recordConfigAlreadyExists) {
        config.records[table].push({
          contentField,
          fileName
        });
      }
    }
  );

  saveConfigFile(config);
  await Promise.all(writeFilePromises);
  return filesWritten;
}
exports.writeFilesForTable = writeFilesForTable;