notifications init

ops/migrations/20180913000513_create_accounts.js

@@ -5,7 +5,7 @@ exports.up = async knex => {
         table.string('name', 42).notNullable().unique();
         table.string('password').notNullable();
         table.string('token', 64).notNullable();
-        table.timestamp('token_expiry');
+        table.timestamp('token_expiry').notNullable();
 
         table.index('name');
         table.index('id');

ops/migrations/20190616170750_notifications.js

@@ -0,0 +1,41 @@
+const notify = `
+CREATE OR REPLACE FUNCTION notify_event() RETURNS TRIGGER AS $$
+    DECLARE
+        record RECORD;
+        id UUID;
+        payload JSON;
+    BEGIN
+    IF (TG_OP = 'DELETE') THEN
+        id = OLD.id;
+    ELSE
+        id = NEW.id;
+    END IF;
+
+    payload = json_build_object(
+        'table', TG_TABLE_NAME,
+        'action', TG_OP,
+        'id', id
+    );
+
+    PERFORM pg_notify('events', payload::text);
+
+    RETURN NULL;
+    END;
+
+$$ LANGUAGE plpgsql;
+`;
+
+const trigger = table => `
+CREATE TRIGGER notify_${table}_event
+AFTER INSERT OR UPDATE OR DELETE ON ${table}
+    FOR EACH ROW EXECUTE PROCEDURE notify_event();
+`;
+
+exports.up = async knex => {
+    await knex.raw(notify);
+    await knex.raw(trigger('accounts'));
+    await knex.raw(trigger('games'));
+    await knex.raw(trigger('instances'));
+};
+
+exports.down = async () => {};