Most of the way through nip01

db/schema.sql

@@ -87,4 +87,95 @@ BEGIN
     AND kind = NEW.kind 
     AND event_type = 'replaceable'
     AND id != NEW.id;
-END;
+END;
+
+-- Persistent Subscriptions Logging Tables (Phase 2)
+-- Optional database logging for subscription analytics and debugging
+
+-- Subscription events log
+CREATE TABLE subscription_events (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    subscription_id TEXT NOT NULL,           -- Subscription ID from client
+    client_ip TEXT NOT NULL,                 -- Client IP address
+    event_type TEXT NOT NULL CHECK (event_type IN ('created', 'closed', 'expired', 'disconnected')),
+    filter_json TEXT,                        -- JSON representation of filters (for created events)
+    events_sent INTEGER DEFAULT 0,           -- Number of events sent to this subscription
+    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    ended_at INTEGER,                        -- When subscription ended (for closed/expired/disconnected)
+    duration INTEGER                         -- Computed: ended_at - created_at
+);
+
+-- Subscription metrics summary
+CREATE TABLE subscription_metrics (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    date TEXT NOT NULL,                      -- Date (YYYY-MM-DD)
+    total_created INTEGER DEFAULT 0,         -- Total subscriptions created
+    total_closed INTEGER DEFAULT 0,          -- Total subscriptions closed
+    total_events_broadcast INTEGER DEFAULT 0, -- Total events broadcast
+    avg_duration REAL DEFAULT 0,            -- Average subscription duration
+    peak_concurrent INTEGER DEFAULT 0,       -- Peak concurrent subscriptions
+    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    UNIQUE(date)
+);
+
+-- Event broadcasting log (optional, for detailed analytics)
+CREATE TABLE event_broadcasts (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    event_id TEXT NOT NULL,                  -- Event ID that was broadcast
+    subscription_id TEXT NOT NULL,           -- Subscription that received it
+    client_ip TEXT NOT NULL,                 -- Client IP
+    broadcast_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    FOREIGN KEY (event_id) REFERENCES events(id)
+);
+
+-- Indexes for subscription logging performance
+CREATE INDEX idx_subscription_events_id ON subscription_events(subscription_id);
+CREATE INDEX idx_subscription_events_type ON subscription_events(event_type);
+CREATE INDEX idx_subscription_events_created ON subscription_events(created_at DESC);
+CREATE INDEX idx_subscription_events_client ON subscription_events(client_ip);
+
+CREATE INDEX idx_subscription_metrics_date ON subscription_metrics(date DESC);
+
+CREATE INDEX idx_event_broadcasts_event ON event_broadcasts(event_id);
+CREATE INDEX idx_event_broadcasts_sub ON event_broadcasts(subscription_id);
+CREATE INDEX idx_event_broadcasts_time ON event_broadcasts(broadcast_at DESC);
+
+-- Trigger to update subscription duration when ended
+CREATE TRIGGER update_subscription_duration
+    AFTER UPDATE OF ended_at ON subscription_events
+    WHEN NEW.ended_at IS NOT NULL AND OLD.ended_at IS NULL
+BEGIN
+    UPDATE subscription_events
+    SET duration = NEW.ended_at - NEW.created_at
+    WHERE id = NEW.id;
+END;
+
+-- View for subscription analytics
+CREATE VIEW subscription_analytics AS
+SELECT
+    date(created_at, 'unixepoch') as date,
+    COUNT(*) as subscriptions_created,
+    COUNT(CASE WHEN ended_at IS NOT NULL THEN 1 END) as subscriptions_ended,
+    AVG(CASE WHEN duration IS NOT NULL THEN duration END) as avg_duration_seconds,
+    MAX(events_sent) as max_events_sent,
+    AVG(events_sent) as avg_events_sent,
+    COUNT(DISTINCT client_ip) as unique_clients
+FROM subscription_events
+GROUP BY date(created_at, 'unixepoch')
+ORDER BY date DESC;
+
+-- View for current active subscriptions (from log perspective)
+CREATE VIEW active_subscriptions_log AS
+SELECT
+    subscription_id,
+    client_ip,
+    filter_json,
+    events_sent,
+    created_at,
+    (strftime('%s', 'now') - created_at) as duration_seconds
+FROM subscription_events
+WHERE event_type = 'created'
+AND subscription_id NOT IN (
+    SELECT subscription_id FROM subscription_events
+    WHERE event_type IN ('closed', 'expired', 'disconnected')
+);