Class BrowserGate.RejectionLog

java.lang.Object
com.iizix.jetty.BrowserGate.RejectionLog
Enclosing class:
BrowserGate
public static final class BrowserGate.RejectionLog extends Object
The INFO line of a rejected load, throttled to one per User-Agent per interval, so that production shows how many users the sorry page reaches without a bot filling the log.

The line carries the entry name, the appID and the User-Agent, both truncated and with every control character replaced by '?', and nothing else: no address, no header, no cookie. The throttle is keyed by that truncated User-Agent and holds at most its capacity of them; when full, the entries older than the interval go first, then the eldest. An evicted User-Agent may therefore log again within the interval, which bounds memory rather than lines: a client that changes its User-Agent on every request gets a line per request whatever the throttle does.

Author:
Christopher Mindus

  • Constructor Details

    • RejectionLog

      public RejectionLog(LongSupplier clock, int capacity, Consumer<String> sink)
      Creates a rejection log.
      Parameters:
      clock - The clock in milliseconds, System::currentTimeMillis in production.
      capacity - The most User-Agents remembered, at least 1.
      sink - Receives each line.
      Throws:
      IllegalArgumentException - If the capacity is below 1.

  • Method Details

    • log

      public boolean log(BrowserGate.Entry entry, String userAgent, String appID)
      Logs a rejected load, unless the same User-Agent was logged less than an interval ago.
      Parameters:
      entry - The entry that rejected the Browser, null when it passed: nothing is logged.
      userAgent - The User-Agent header, null for none.
      appID - The appID of the request, null for none.
      Returns:
      true when a line was written.

    • size

      public int size()
      Gets the number of User-Agents remembered.
      Returns:
      The size, never above the capacity.