From 40a07c3f57dd979d8e2bb6eb316d465ce3230586 Mon Sep 17 00:00:00 2001
From: James Rose <james@jbpr.net>
Date: Mon, 12 Jun 2023 15:17:06 +0100
Subject: [PATCH] Reduce Sentry sample rate so that we don't hit our quota
 (#1691)

- As we migrate more organisations onto the service we need to be more conservative.
- This PR removes tracing on healthchecks entirely, whilst lowering everything else from 0.02 to 0.01.
---
 config/initializers/sentry.rb | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/config/initializers/sentry.rb b/config/initializers/sentry.rb
index 3b7262837..596487d40 100644
--- a/config/initializers/sentry.rb
+++ b/config/initializers/sentry.rb
@@ -1,5 +1,24 @@
 Sentry.init do |config|
   config.breadcrumbs_logger = %i[active_support_logger http_logger]
   config.enabled_environments = %w[production staging review]
-  config.traces_sample_rate = 0.2
+
+  config.traces_sampler = lambda do |sampling_context|
+    transaction_context = sampling_context[:transaction_context]
+    op = transaction_context[:op]
+    transaction_name = transaction_context[:name]
+
+    case op
+    when /request/
+      case transaction_name
+      when /health/
+        0.0 # ignore healthcheck requests
+      else
+        0.01
+      end
+    when /sidekiq/
+      0.001
+    else
+      0.0 # We don't care about performance of other things
+    end
+  end
 end