Fix docker stats to make it work on centos 7.

issue #58
issue #84

CHANGELOG.md

@@ -13,6 +13,7 @@ will still be backwards compatible if only `url` is specified.
 - [#175](https://github.com/influxdb/telegraf/issues/175): Set write precision before gathering metrics
 - [#178](https://github.com/influxdb/telegraf/issues/178): redis plugin, multiple server thread hang bug
 - Fix net plugin on darwin
+- [#84](https://github.com/influxdb/telegraf/issues/84): Fix docker plugin on CentOS. Thanks @neezgee!
 
 ## v0.1.8 [2015-09-04]
 

plugins/system/ps/docker/docker_linux.go

@@ -4,6 +4,7 @@ package docker
 
 import (
 	"encoding/json"
+        "os"
 	"os/exec"
 	"path"
 	"strconv"
@@ -48,9 +49,13 @@ func CgroupCPU(containerid string, base string) (*cpu.CPUTimesStat, error) {
 	if len(base) == 0 {
 		base = "/sys/fs/cgroup/cpuacct/docker"
 	}
-	path := path.Join(base, containerid, "cpuacct.stat")
+	statfile := path.Join(base, containerid, "cpuacct.stat")
 
-	lines, err := common.ReadLines(path)
+        if _, err := os.Stat(statfile); os.IsNotExist(err) {
+            statfile = path.Join("/sys/fs/cgroup/cpuacct/system.slice",  "docker-" + containerid + ".scope", "cpuacct.stat")
+        }
+
+	lines, err := common.ReadLines(statfile)
 	if err != nil {
 		return nil, err
 	}
@@ -86,12 +91,17 @@ func CgroupMem(containerid string, base string) (*CgroupMemStat, error) {
 	if len(base) == 0 {
 		base = "/sys/fs/cgroup/memory/docker"
 	}
-	path := path.Join(base, containerid, "memory.stat")
+	statfile := path.Join(base, containerid, "memory.stat")
+
+        if _, err := os.Stat(statfile); os.IsNotExist(err) {
+            statfile = path.Join("/sys/fs/cgroup/memory/system.slice",  "docker-" + containerid + ".scope", "memory.stat")
+        }
+
 	// empty containerid means all cgroup
 	if len(containerid) == 0 {
 		containerid = "all"
 	}
-	lines, err := common.ReadLines(path)
+	lines, err := common.ReadLines(statfile)
 	if err != nil {
 		return nil, err
 	}