Add numerical representation of Consul health check state. (#2277)

plugins/inputs/consul/README.md

@@ -35,12 +35,19 @@ Fields:
 - check_name
 - service_id
 - status
+- passing
+- critical
+- warning
+
+`passing`, `critical`, and `warning` are integer representations of the health
+check state. A value of `1` represents that the status was the state of the
+the health check at this sample.
 
 ## Example output
 
 ```
 $ telegraf --config ./telegraf.conf -input-filter consul -test
 * Plugin: consul, Collection 1
-> consul_health_checks,host=wolfpit,node=consul-server-node,check_id="serfHealth" check_name="Serf Health Status",service_id="",status="passing" 1464698464486439902
-> consul_health_checks,host=wolfpit,node=consul-server-node,service_name=www.example.com,check_id="service:www-example-com.test01" check_name="Service 'www.example.com' check",service_id="www-example-com.test01",status="critical" 1464698464486519036
+> consul_health_checks,host=wolfpit,node=consul-server-node,check_id="serfHealth" check_name="Serf Health Status",service_id="",status="passing",passing=1i,critical=0i,warning=0i 1464698464486439902
+> consul_health_checks,host=wolfpit,node=consul-server-node,service_name=www.example.com,check_id="service:www-example-com.test01" check_name="Service 'www.example.com' check",service_id="www-example-com.test01",status="critical",passing=0i,critical=1i,warning=0i 1464698464486519036
 ```

plugins/inputs/consul/consul.go

@@ -97,7 +97,12 @@ func (c *Consul) GatherHealthCheck(acc telegraf.Accumulator, checks []*api.Healt
 
 		record["check_name"] = check.Name
 		record["service_id"] = check.ServiceID
+
 		record["status"] = check.Status
+		record["passing"] = 0
+		record["critical"] = 0
+		record["warning"] = 0
+		record[check.Status] = 1
 
 		tags["node"] = check.Node
 		tags["service_name"] = check.ServiceName

plugins/inputs/consul/consul_test.go

@@ -24,6 +24,9 @@ func TestGatherHealtCheck(t *testing.T) {
 	expectedFields := map[string]interface{}{
 		"check_name": "foo.health",
 		"status":     "passing",
+		"passing":    1,
+		"critical":   0,
+		"warning":    0,
 		"service_id": "foo.123",
 	}