Rework postgres_mixin dashboard

Rework the postgres_mixing dashboard to be more composable. The goal is for this to be more maintainable long term. I don't know jsonnet very well, but following other projects, this appears to be in line.

This replaces the postgres-overview.json dashboard with an overview.json dashboard with the same panels. While the dashboard does not match perfectly, it does include the same data but with the correct metrics.

Signed-off-by: Joe Adams <github@joeadams.io>

Author: sysadmind

.gitignore

@@ -20,3 +20,4 @@
 /.metrics.*.removed
 /tools/src
 /vendor
+vendor/

postgres_mixin/config.libsonnet

@@ -1,5 +1,8 @@
 {
   _config+:: {
     postgresExporterSelector: '',
+
+    dashboardNamePrefix: 'Postgres Exporter / ',
+    dashboardTags: ['postgres-exporter-mixin'],
   },
 }

postgres_mixin/dashboards.jsonnet

@@ -0,0 +1,3 @@
+local dashboards = (import 'mixin.libsonnet').grafanaDashboards;
+
+{ [name]: dashboards[name] for name in std.objectFields(dashboards)}

postgres_mixin/dashboards/dashboards.libsonnet

@@ -1,5 +1,41 @@
+local g = import 'g.libsonnet';
+
+local dashboard = g.dashboard;
+local row = g.panel.row;
+
+local panels = import './panels.libsonnet';
+local variables = import './variables.libsonnet';
+local queries = import './queries.libsonnet';
+
+// import config
+local c = import '../config.libsonnet';
+
 {
   grafanaDashboards+:: {
-    'postgres-overview.json': (import 'postgres-overview.json'),
-  },
+    'overview.json':
+      dashboard.new('%s Overview' % $._config.dashboardNamePrefix)
+      + dashboard.withTags($._config.dashboardTags)
+      + dashboard.withRefresh('1m')
+      + dashboard.time.withFrom(value='now-1h')
+      + dashboard.graphTooltip.withSharedCrosshair()
+      + dashboard.withVariables([
+        variables.datasource,
+      ])
+      + dashboard.withPanels(
+        g.util.grid.makeGrid([
+          row.new('Overview')
+          + row.withPanels([
+            panels.stat.qps('QPS', queries.qps),
+            panels.timeSeries.ratio1('Cache Hit Ratio', queries.cacheHitRatio),
+            panels.timeSeries.base('Active Connections', queries.activeConnections)
+          ]),
+          row.new('server')
+          + row.withPanels([
+            panels.timeSeries.base('Conflicts/Deadlocks', [queries.conflicts, queries.deadlocks]),
+            panels.timeSeries.base('Buffers', [queries.buffersAlloc, queries.buffersBackendFsync, queries.buffersBackend, queries.buffersClean, queries.buffersCheckpoint]),
+            panels.timeSeries.base('Rows', [queries.databaseTupFetched, queries.databaseTupReturned, queries.databaseTupInserted, queries.databaseTupUpdated, queries.databaseTupDeleted]),
+          ]),
+        ])
+      )
+  }
 }

postgres_mixin/dashboards/g.libsonnet

@@ -0,0 +1 @@
+import 'github.com/grafana/grafonnet/gen/grafonnet-latest/main.libsonnet'

postgres_mixin/dashboards/panels.libsonnet

@@ -0,0 +1,30 @@
+local g = import 'g.libsonnet';
+
+{
+  stat: {
+    local stat = g.panel.stat,
+
+    base(title, targets):
+      stat.new(title)
+      +stat.queryOptions.withTargets(targets),
+
+    qps: self.base,
+  },
+
+  timeSeries: {
+    local timeSeries = g.panel.timeSeries,
+
+    base(title, targets):
+      timeSeries.new(title)
+      +timeSeries.queryOptions.withTargets(targets),
+
+    ratio(title, targets):
+      self.base(title, targets)
+      + timeSeries.standardOptions.withUnit('percentunit'),
+
+    ratio1(title, targets):
+      self.ratio(title, targets)
+      + timeSeries.standardOptions.withUnit('percentunit')
+      + timeSeries.standardOptions.withMax(1)
+  }
+}