Add collectd/chrony monitor

Author: Ben Keith

docs/monitor-config.md

@@ -11,6 +11,7 @@ along with their possible configuration options:
 - [collectd/activemq](./monitors/collectd-activemq.md)
 - [collectd/apache](./monitors/collectd-apache.md)
 - [collectd/cassandra](./monitors/collectd-cassandra.md)
+- [collectd/chrony](./monitors/collectd-chrony.md)
 - [collectd/consul](./monitors/collectd-consul.md)
 - [collectd/couchbase](./monitors/collectd-couchbase.md)
 - [collectd/cpu](./monitors/collectd-cpu.md)

docs/monitors/collectd-chrony.md

@@ -0,0 +1,30 @@
+<!--- GENERATED BY gomplate from scripts/docs/monitor-page.md.tmpl --->
+
+# collectd/chrony
+
+ Collectd NTP data from a chronyd instance
+
+See https://collectd.org/documentation/manpages/collectd.conf.5.shtml#plugin_chrony
+
+
+Monitor Type: `collectd/chrony`
+
+[Monitor Source Code](https://github.com/signalfx/signalfx-agent/tree/master/internal/monitors/collectd/chrony)
+
+**Accepts Endpoints**: No
+
+**Multiple Instances Allowed**: **No**
+
+## Configuration
+
+| Config option | Required | Type | Description |
+| --- | --- | --- | --- |
+| `host` | **yes** | `string` | The hostname of the chronyd instance |
+| `port` | no | `integer` | The UDP port number of the chronyd instance.  Defaults to 323 in collectd if unspecified. |
+| `timeout` | no | `unsigned integer` | How long to wait for a response from chronyd before considering it down. Defaults to 2 seconds in the collectd plugin if not specified |
+
+
+
+
+
+

internal/core/modules_collectd.go

@@ -10,6 +10,7 @@ import (
 	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/activemq"
 	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/apache"
 	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/cassandra"
+	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/chrony"
 	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/consul"
 	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/couchbase"
 	_ "github.com/signalfx/signalfx-agent/internal/monitors/collectd/cpu"

internal/monitors/collectd/chrony/chrony.go

@@ -0,0 +1,51 @@
+// +build !windows
+
+package chrony
+
+//go:generate collectd-template-to-go chrony.tmpl
+
+import (
+	"github.com/signalfx/signalfx-agent/internal/core/config"
+	"github.com/signalfx/signalfx-agent/internal/monitors"
+	"github.com/signalfx/signalfx-agent/internal/monitors/collectd"
+)
+
+const monitorType = "collectd/chrony"
+
+// MONITOR(collectd/chrony): Collectd NTP data from a chronyd instance
+//
+// See https://collectd.org/documentation/manpages/collectd.conf.5.shtml#plugin_chrony
+
+func init() {
+	monitors.Register(monitorType, func() interface{} {
+		return &Monitor{
+			MonitorCore: *collectd.NewMonitorCore(CollectdTemplate),
+		}
+	}, &Config{})
+}
+
+// Config is the monitor-specific config with the generic config embedded
+type Config struct {
+	// This cannot be multi instance until there is a way to differentiate them
+	// in collectd
+	config.MonitorConfig `singleInstance:"true"`
+
+	// The hostname of the chronyd instance
+	Host string `yaml:"host" validate:"required" default:"localhost"`
+	// The UDP port number of the chronyd instance.  Defaults to 323 in
+	// collectd if unspecified.
+	Port *uint16 `yaml:"port"`
+	// How long to wait for a response from chronyd before considering it down.
+	// Defaults to 2 seconds in the collectd plugin if not specified
+	Timeout *uint `yaml:"timeout"`
+}
+
+// Monitor is the main type that represents the monitor
+type Monitor struct {
+	collectd.MonitorCore
+}
+
+// Configure configures and runs the plugin in collectd
+func (m *Monitor) Configure(conf *Config) error {
+	return m.SetConfigurationAndRun(conf)
+}

internal/monitors/collectd/chrony/chrony.tmpl

@@ -0,0 +1,21 @@
+LoadPlugin chrony
+<Plugin chrony>
+  Host "{{.Host}}"
+{{with .Port}}
+  Port "{{.}}"
+{{end}}
+{{with .Timeout}}
+  Timeout "{{.}}"
+{{end}}
+</Plugin>
+
+<Chain "PostCache">
+  <Rule "set_chrony_monitor_id">
+    <Match "regex">
+      Plugin "^chrony$"
+    </Match>
+    <Target "set">
+      MetaData "monitorID" "{{.MonitorID}}"
+    </Target>
+  </Rule>
+</Chain>

tests/monitors/chrony_test.py

@@ -0,0 +1,26 @@
+"""
+Integration tests for chrony monitor.
+"""
+from tests.helpers.util import wait_for, run_agent
+from tests.helpers.assertions import has_log_message
+
+chrony_config = """
+monitors:
+  - type: collectd/chrony
+    host: localhost
+    port: 23874
+"""
+
+def test_chrony():
+    """
+    Unfortunately, chronyd is very hard to run in a test environment without
+    giving it the ability to change the time which we don't want, so just check
+    for an error message ensuring that the monitor actually did configure it,
+    even if it doesn't emit any metrics.
+    """
+    with run_agent(chrony_config) as [_, get_output, _]:
+        def has_error():
+            return has_log_message(get_output(), level="error",
+                                   message="chrony plugin: chrony_query (REQ_TRACKING) failed")
+
+        assert wait_for(has_error), "Didn't get chrony error message"