sitestat/source/live_tracker.d

125 lines
3.8 KiB
D

module live_tracker;
import data;
import handy_httpd.components.websocket.handler;
import slf4d;
import std.uuid;
import std.datetime;
import std.json;
import std.string;
import std.parallelism;
import core.sync.rwmutex;
/**
* A websocket message handler that keeps track of each connected session, and
* records information about that session's activities.
*/
class LiveTracker : WebSocketMessageHandler {
private StatSession[UUID] sessions;
static immutable uint DEFAULT_MIN_SESSION_DURATION = 1000;
private immutable uint minSessionDurationMillis;
private TaskPool sessionPersistencePool;
private ReadWriteMutex sessionsMutex;
this(uint minSessionDurationMillis = DEFAULT_MIN_SESSION_DURATION) {
this.minSessionDurationMillis = minSessionDurationMillis;
this.sessionPersistencePool = new TaskPool(1);
this.sessionsMutex = new ReadWriteMutex();
}
override void onConnectionEstablished(WebSocketConnection conn) {
debugF!"Connection established: %s"(conn.id);
synchronized(sessionsMutex.writer) {
sessions[conn.id] = StatSession(
conn.id,
Clock.currTime(UTC())
);
}
infoF!"Started tracking session %s"(conn.id);
}
override void onTextMessage(WebSocketTextMessage msg) {
StatSession* session;
synchronized(sessionsMutex.reader) {
session = msg.conn.id in sessions;
}
if (session is null) {
warnF!"Got a websocket text message from a client without a session: %s"(msg.conn.id);
return;
}
JSONValue obj = parseJSON(msg.payload);
immutable string msgType = obj.object["type"].str;
if (msgType == MessageTypes.IDENT) {
handleIdent(obj, session);
} else if (msgType == MessageTypes.EVENT) {
session.eventCount++;
// session.events ~= EventRecord(
// Clock.currTime(UTC()),
// obj.object["event"].str
// );
}
}
override void onConnectionClosed(WebSocketConnection conn) {
StatSession* session;
synchronized(sessionsMutex.reader) {
session = conn.id in sessions;
}
if (session !is null && session.isValid) {
SysTime endTimestamp = Clock.currTime(UTC());
Duration dur = endTimestamp - session.connectedAt;
if (dur.total!"msecs" >= minSessionDurationMillis) {
infoF!"Session lasted %d seconds, %d events."(dur.total!"seconds", session.eventCount);
}
immutable storedSession = StoredSession(
-1,
session.connectedAt,
endTimestamp,
session.url,
session.href,
session.userAgent,
session.eventCount
);
this.sessionPersistencePool.put(task!storeSession(storedSession));
}
synchronized(sessionsMutex.writer) {
sessions.remove(conn.id);
}
}
private void handleIdent(JSONValue msg, StatSession* session) {
string fullUrl = msg.object["href"].str;
session.href = fullUrl;
ptrdiff_t paramsIdx = std.string.indexOf(fullUrl, '?');
if (paramsIdx == -1) {
session.url = fullUrl;
} else {
session.url = fullUrl[0 .. paramsIdx];
}
session.userAgent = msg.object["userAgent"].str;
}
}
private enum MessageTypes : string {
IDENT = "ident",
EVENT = "event"
}
struct StatSession {
UUID id;
SysTime connectedAt;
string url = null;
string href = null;
string userAgent = null;
uint eventCount = 0;
bool isValid() const {
return url !is null && href !is null && userAgent !is null;
}
}
struct EventRecord {
SysTime timestamp;
string eventType;
}