netlify-cli/src/utils/detect-server.js

const path = require('path')
const chalk = require('chalk')
const { NETLIFYDEVLOG } = require('./logo')
const inquirer = require('inquirer')
const fuzzy = require('fuzzy')
const fs = require('fs')

module.exports.serverSettings = async devConfig => {
  const detectors = fs
    .readdirSync(path.join(__dirname, '..', 'detectors'))
    .filter(x => x.endsWith('.js')) // only accept .js detector files
    .map(det => {
      try {
        return require(path.join(__dirname, '..', `detectors/${det}`))
      } catch (err) {
        console.error(
          `failed to load detector: ${chalk.yellow(
            det
          )}, this is likely a bug in the detector, please file an issue in netlify-dev-plugin`,
          err
        )
        return null
      }
    })
    .filter(Boolean)
  let settingsArr = []
  let settings = null
  for (const i in detectors) {
    const detectorResult = detectors[i]()
    if (detectorResult) settingsArr.push(detectorResult)
  }
  if (settingsArr.length === 1) {
    // vast majority of projects will only have one matching detector
    settings = settingsArr[0]
    settings.args = settings.possibleArgsArrs[0] // just pick the first one
    if (!settings.args) {
      const { scripts } = JSON.parse(fs.readFileSync('package.json', { encoding: 'utf8' }))
      // eslint-disable-next-line no-console
      console.error(
        'empty args assigned, this is an internal Netlify Dev bug, please report your settings and scripts so we can improve',
        { scripts, settings }
      )
      // eslint-disable-next-line no-process-exit
      process.exit(1)
    }
  } else if (settingsArr.length > 1) {
    /** multiple matching detectors, make the user choose */
    // lazy loading on purpose
    inquirer.registerPrompt('autocomplete', require('inquirer-autocomplete-prompt'))
    const scriptInquirerOptions = formatSettingsArrForInquirer(settingsArr)
    const { chosenSetting } = await inquirer.prompt({
      name: 'chosenSetting',
      message: `Multiple possible start commands found`,
      type: 'autocomplete',
      source: async function(_, input) {
        if (!input || input === '') {
          return scriptInquirerOptions
        }
        // only show filtered results
        return filterSettings(scriptInquirerOptions, input)
      }
    })
    settings = chosenSetting // finally! we have a selected option
    // TODO: offer to save this setting to netlify.toml so you dont keep doing this
  }

  /** everything below assumes we have settled on one detector */
  const tellUser = settingsField => dV =>
    // eslint-disable-next-line no-console
    console.log(
      `${NETLIFYDEVLOG} Overriding ${chalk.yellow(settingsField)} with setting derived from netlify.toml [dev] block: `,
      dV
    )

  if (devConfig) {
    settings = settings || {}
    if (devConfig.command) {
      settings.command = assignLoudly(devConfig.command.split(/\s/)[0], settings.command || null, tellUser('command')) // if settings.command is empty, its bc no settings matched
      let devConfigArgs = devConfig.command.split(/\s/).slice(1)
      if (devConfigArgs[0] === 'run') devConfigArgs = devConfigArgs.slice(1)
      settings.args = assignLoudly(devConfigArgs, settings.command || null, tellUser('command')) // if settings.command is empty, its bc no settings matched
    }
    if (devConfig.port) settings.port = devConfig.port
    if (devConfig.targetPort) {
      settings.proxyPort = devConfig.targetPort
      settings.urlRegexp = devConfig.urlRegexp || new RegExp(`(http://)([^:]+:)${devConfig.targetPort}(/)?`, 'g')
    }
    if (devConfig.functionsPort) settings.functionsPort = devConfig.functionsPort
    settings.dist = devConfig.publish || settings.dist // dont loudassign if they dont need it

    if (devConfig.jwtRolePath) settings.jwtRolePath = devConfig.jwtRolePath
  }
  return settings
}

/** utilities for the inquirer section above */
function filterSettings(scriptInquirerOptions, input) {
  const filteredSettings = fuzzy.filter(input, scriptInquirerOptions.map(x => x.name))
  const filteredSettingNames = filteredSettings.map(x => (input ? x.string : x))
  return scriptInquirerOptions.filter(t => filteredSettingNames.includes(t.name))
}

/** utiltities for the inquirer section above */
function formatSettingsArrForInquirer(settingsArr) {
  let ans = []
  settingsArr.forEach(setting => {
    setting.possibleArgsArrs.forEach(args => {
      ans.push({
        name: `[${chalk.yellow(setting.type)}] ${setting.command} ${args.join(' ')}`,
        value: { ...setting, args },
        short: setting.type + '-' + args.join(' ')
      })
    })
  })
  return ans
}
// if first arg is undefined, use default, but tell user about it in case it is unintentional
function assignLoudly(
  optionalValue,
  defaultValue,
  // eslint-disable-next-line no-console
  tellUser = dV => console.log(`No value specified, using fallback of `, dV)
) {
  if (defaultValue === undefined) throw new Error('must have a defaultValue')
  if (defaultValue !== optionalValue && optionalValue === undefined) {
    tellUser(defaultValue)
    return defaultValue
  }
  return optionalValue
}