Function validationMiddleware

middleware/api/search.js:166–243

(req, res, next)

class ValidationError extends Error {}

const validationMiddleware = (req, res, next) => {
  const params = [
    { key: 'query' },
    {
      key: 'version',
      default_: 'dotcom',
      validate: (v) => {
        if (versionAliases[v] || allVersions[v]) return true
        const valid = [...Object.keys(versionAliases), ...Object.keys(allVersions)]
        throw new ValidationError(`'${v}' not in ${valid}`)
      },
    },
    { key: 'language', default_: 'en', validate: (v) => v in languages },
    {
      key: 'size',
      default_: DEFAULT_SIZE,
      cast: (v) => parseInt(v, 10),
      validate: (v) => v >= 0 && v <= MAX_SIZE,
    },
    {
      key: 'page',
      default_: DEFAULT_PAGE,
      cast: (v) => parseInt(v, 10),
      validate: (v) => v >= 1 && v <= MAX_PAGE,
    },
    { key: 'sort', default_: DEFAULT_SORT, validate: (v) => POSSIBLE_SORTS.includes(v) },
    {
      key: 'highlights',
      default_: DEFAULT_HIGHLIGHT_FIELDS,
      cast: (v) => (Array.isArray(v) ? v : [v]),
      validate: (v) => {
        for (const highlight of v) {
          if (!POSSIBLE_HIGHLIGHT_FIELDS.includes(highlight)) {
            throw new ValidationError(`highlight value '${highlight}' is not valid`)
          }
        }
        return true
      },
    },
    { key: 'autocomplete', default_: false, cast: toBoolean },
    { key: 'debug', default_: process.env.NODE_ENV === 'development', cast: toBoolean },
  ]

  const search = {}
  for (const { key, default_, cast, validate } of params) {
    let value = req.query[key]
    if (!value || (typeof value === 'string' && !value.trim())) {
      if (default_ === undefined) {
        // no value and no default, bad!
        return res.status(400).json({ error: `No truthy value for key '${key}'` })
      }
      value = default_
    }
    if (cast) {
      value = cast(value)
    }
    try {
      if (validate && !validate(value)) {