connect_json.mv

# Support for parsing JSON requests and sending JSON responses in Connect

connect_json = ^(req, res, next) {
  # A request method for ending the response with a JSON payload
  res.endJSON = ^(object) {
    if (arguments.keywords) {
      # Use Move keyword arguments as the object
      object = arguments.keywords
      delete object.__kw
    }
    body = JSON object
    res.setHeader 'Content-Type', 'application/json'
    res.setHeader 'Content-Length', Text body.length
    res.end body
  }

  # Read and parse JSON request payloads, later accessible from req.message
  if (req.method == 'POST' || req.method == 'PUT') {
    ct = req.headers['content-type']
    length = parseInt req.headers['content-length']
    if (isNaN length) {
      res.statusCode = 400
      res.end 'Missing or malformed Content-Length header in request'
      return
    } else if (length > connect_json.max_request_body_size) {
      # We don't handle requests this big
      return next()
    }
    if (ct && ct.indexOf('application/json') == 0) {
      buffer = ''
      req.setEncoding 'utf8'
      req.on 'data', ^(chunk) {
        if (buffer.length + chunk.length > length) {
          # Kill the connection on suspected buffer overflow attempt
          req.connection.destroy()
          return
        }
        buffer += chunk
      }
      req.on 'end', ^{
        # Parse JSON payload
        try {
          message = JSON.parse buffer
        } catch (err) {
          res.statusCode = 400
          res.end 'Malformed JSON: '+(err.message || err)
          return
        }
        # Add message to req.message or set/replace it
        if (req.message && message && typeof message == 'object' &&
            typeof req.message == 'object') {
          for (k in message) req.message[k] = message[k]
        } else {
          req.message = message
        }
        next()
      }
      # "wait" for the request to complete
      return
    }
  }
  # This is not a request with a JSON payload. Just move along.
  next()
}

# Maximum size of a request body to parse (only applies to application/json)
connect_json.max_request_body_size = 5 * 1024000

module.exports = connect_json