Custom queries for prometheus

- Tests for prometheus queries

- fix rubocop warnings

- Remove unused method. Add more queries to deployment queries.

- Wrap BaseQuery in module hierarchy

Renname Prometheus class to PrometheusClient

3 files changed, 72 insertions, 0 deletions

diff --git a/lib/gitlab/prometheus/queries/base_query.rb b/lib/gitlab/prometheus/queries/base_query.rb
new file mode 100644
index 00000000000..2a2eb4ae57f
--- /dev/null
+++ b/lib/gitlab/prometheus/queries/base_query.rb
@@ -0,0 +1,26 @@
+module Gitlab
+  module Prometheus
+    module Queries
+      class BaseQuery
+        attr_accessor :client
+        delegate :query_range, :query, to: :client, prefix: true
+
+        def raw_memory_usage_query(environment_slug)
+          %{avg(container_memory_usage_bytes{container_name!="POD",environment="#{environment_slug}"}) / 2^20}
+        end
+
+        def raw_cpu_usage_query(environment_slug)
+          %{avg(rate(container_cpu_usage_seconds_total{container_name!="POD",environment="#{environment_slug}"}[2m])) * 100}
+        end
+
+        def initialize(client)
+          @client = client
+        end
+
+        def query(*args)
+          raise NotImplementedError
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/prometheus/queries/deployment_query.rb b/lib/gitlab/prometheus/queries/deployment_query.rb
new file mode 100644
index 00000000000..98675c179b1
--- /dev/null
+++ b/lib/gitlab/prometheus/queries/deployment_query.rb
@@ -0,0 +1,26 @@
+module Gitlab::Prometheus::Queries
+  class DeploymentQuery < BaseQuery
+    def query(deployment_id)
+      deployment = Deployment.find_by(id: deployment_id)
+      environment_slug = deployment.environment.slug
+
+      memory_query = raw_memory_usage_query(environment_slug)
+      memory_avg_query = %{avg(avg_over_time(container_memory_usage_bytes{container_name!="POD",environment="#{environment_slug}"}[30m]))}
+      cpu_query = raw_cpu_usage_query(environment_slug)
+      cpu_avg_query = %{avg(rate(container_cpu_usage_seconds_total{container_name!="POD",environment="#{environment_slug}"}[30m])) * 100}
+
+      timeframe_start = (deployment.created_at - 30.minutes).to_f
+      timeframe_end = (deployment.created_at + 30.minutes).to_f
+
+      {
+        memory_values: client_query_range(memory_query, start: timeframe_start, stop: timeframe_end),
+        memory_before: client_query(memory_avg_query, time: deployment.created_at.to_f),
+        memory_after: client_query(memory_avg_query, time: timeframe_end),
+
+        cpu_values: client_query_range(cpu_query, start: timeframe_start, stop: timeframe_end),
+        cpu_before: client_query(cpu_avg_query, time: deployment.created_at.to_f),
+        cpu_after: client_query(cpu_avg_query, time: timeframe_end),
+      }
+    end
+  end
+end
diff --git a/lib/gitlab/prometheus/queries/environment_query.rb b/lib/gitlab/prometheus/queries/environment_query.rb
new file mode 100644
index 00000000000..9981272220e
--- /dev/null
+++ b/lib/gitlab/prometheus/queries/environment_query.rb
@@ -0,0 +1,20 @@
+module Gitlab::Prometheus::Queries
+  class EnvironmentQuery < BaseQuery
+    def query(environment_id)
+      environment = Environment.find_by(id: environment_id)
+      environment_slug = environment.slug
+      timeframe_start = 8.hours.ago.to_f
+      timeframe_end = Time.now.to_f
+
+      memory_query = raw_memory_usage_query(environment_slug)
+      cpu_query = raw_cpu_usage_query(environment_slug)
+
+      {
+        memory_values: client_query_range(memory_query, start: timeframe_start, stop: timeframe_end),
+        memory_current: client_query(memory_query, time: timeframe_end),
+        cpu_values: client_query_range(cpu_query, start: timeframe_start, stop: timeframe_end),
+        cpu_current: client_query(cpu_query, time: timeframe_end),
+      }
+    end
+  end
+end