Added Sentry performance monitoring to Ghost Server (#19243)

refs ARCH-21

- We currently have NewRelic setup for a few of our largest customers
for monitoring performance, but it is too expensive to enable across all
sites
- Sentry has similar (but simpler) performance monitoring tools to keep
track of response times that are available to us for free, but we just
haven't configured them
- This PR sets up Sentry Performance monitoring for API requests so we
can have one place for monitoring errors + performance so we can stay on
top of response times more easily.
- Tracing is disabled by default, so there is no additional overhead
unless `sentry.tracing.enabled` is set to `true` in the site's config.
Additionally, `sentry.tracing.sampleRate` should be set to a decimal
value between 0 and 1. This value defaults to 0 to avoid accidentally
blowing through quota, and requires a value to explicitly be set in
order to send the traces to Sentry.

ghost/core/core/app.js

@@ -30,7 +30,9 @@ const maintenanceMiddleware = (req, res, next) => {
 const rootApp = () => {
     const app = express('root');
     app.use(sentry.requestHandler);
-
+    if (config.get('sentry')?.tracing?.enabled === true) {
+        app.use(sentry.tracingHandler);
+    }
     app.enable('maintenance');
     app.use(maintenanceMiddleware);
 

ghost/core/core/shared/sentry.js

@@ -59,13 +59,22 @@ if (sentryConfig && !sentryConfig.disabled) {
     const Sentry = require('@sentry/node');
     const version = require('@tryghost/version').full;
     const environment = config.get('env');
-    Sentry.init({
+    const sentryInitConfig = {
         dsn: sentryConfig.dsn,
         release: 'ghost@' + version,
         environment: environment,
         maxValueLength: 1000,
-        beforeSend: beforeSend
-    });
+        integrations: [],
+        beforeSend
+    };
+
+    // Enable tracing if sentry.tracing.enabled is true
+    if (sentryConfig.tracing?.enabled === true) {
+        sentryInitConfig.integrations.push(new Sentry.Integrations.Http({tracing: true}));
+        sentryInitConfig.integrations.push(new Sentry.Integrations.Express());
+        sentryInitConfig.tracesSampleRate = parseFloat(sentryConfig.tracing.sampleRate) || 0.0;
+    }
+    Sentry.init(sentryInitConfig);
 
     module.exports = {
         requestHandler: Sentry.Handlers.requestHandler(),
@@ -82,6 +91,7 @@ if (sentryConfig && !sentryConfig.disabled) {
                 return (error.statusCode === 500);
             }
         }),
+        tracingHandler: Sentry.Handlers.tracingHandler(),
         captureException: Sentry.captureException,
         beforeSend: beforeSend
     };
@@ -95,6 +105,7 @@ if (sentryConfig && !sentryConfig.disabled) {
     module.exports = {
         requestHandler: expressNoop,
         errorHandler: expressNoop,
+        tracingHandler: expressNoop,
         captureException: noop
     };
 }