Remove query validation

This is now done at the CDN level.

server/middleware/parseURL.js

@@ -1,18 +1,6 @@
 const validateNPMPackageName = require('validate-npm-package-name')
 const PackageURL = require('../PackageURL')
 
-const ValidQueryKeys = {
-  main: true,
-  meta: true,
-  json: true // deprecated
-}
-
-function queryIsValid(query) {
-  return Object.keys(query).every(function (key) {
-    return ValidQueryKeys[key]
-  })
-}
-
 /**
  * Parse and validate the URL.
  */
@@ -28,11 +16,6 @@ function parseURL(req, res, next) {
   if (nameErrors)
     return res.status(403).type('text').send(`Invalid package name: ${url.packageName} (${nameErrors.join(', ')})`)
 
-  // Do not allow unrecognized query parameters because
-  // some people use them to bust the cache.
-  if (!queryIsValid(url.query))
-    return res.status(403).type('text').send(`Invalid query: ${url.search}`)
-
   req.packageName = url.packageName
   req.packageVersion = url.packageVersion
   req.packageSpec = `${req.packageName}@${req.packageVersion}`