0.3.0 Removing internal parallelism: twemproxy and rabbitmq

plugins/twemproxy/twemproxy.go

@@ -5,28 +5,21 @@ import (
 	"errors"
 	"io/ioutil"
 	"net"
-	"strings"
-	"sync"
 	"time"
 
 	"github.com/influxdb/telegraf/plugins"
 )
 
 type Twemproxy struct {
-	Instances []TwemproxyInstance
-}
-
-type TwemproxyInstance struct {
 	Addr  string
 	Pools []string
 }
 
 var sampleConfig = `
-  [[plugins.twemproxy.instances]]
-    # Twemproxy stats address and port (no scheme)
-    addr = "localhost:22222"
-    # Monitor pool name
-    pools = ["redis_pool", "mc_pool"]
+  # Twemproxy stats address and port (no scheme)
+  addr = "localhost:22222"
+  # Monitor pool name
+  pools = ["redis_pool", "mc_pool"]
 `
 
 func (t *Twemproxy) SampleConfig() string {
@@ -39,35 +32,7 @@ func (t *Twemproxy) Description() string {
 
 // Gather data from all Twemproxy instances
 func (t *Twemproxy) Gather(acc plugins.Accumulator) error {
-	var wg sync.WaitGroup
-	errorChan := make(chan error, len(t.Instances))
-	for _, inst := range t.Instances {
-		wg.Add(1)
-		go func(inst TwemproxyInstance) {
-			defer wg.Done()
-			if err := inst.Gather(acc); err != nil {
-				errorChan <- err
-			}
-		}(inst)
-	}
-	wg.Wait()
-
-	close(errorChan)
-	errs := []string{}
-	for err := range errorChan {
-		errs = append(errs, err.Error())
-	}
-	if len(errs) == 0 {
-		return nil
-	}
-	return errors.New(strings.Join(errs, "\n"))
-}
-
-// Gather data from one Twemproxy
-func (ti *TwemproxyInstance) Gather(
-	acc plugins.Accumulator,
-) error {
-	conn, err := net.DialTimeout("tcp", ti.Addr, 1*time.Second)
+	conn, err := net.DialTimeout("tcp", t.Addr, 1*time.Second)
 	if err != nil {
 		return err
 	}
@@ -82,14 +47,14 @@ func (ti *TwemproxyInstance) Gather(
 	}
 
 	tags := make(map[string]string)
-	tags["twemproxy"] = ti.Addr
-	ti.processStat(acc, tags, stats)
+	tags["twemproxy"] = t.Addr
+	t.processStat(acc, tags, stats)
 
 	return nil
 }
 
 // Process Twemproxy server stats
-func (ti *TwemproxyInstance) processStat(
+func (t *Twemproxy) processStat(
 	acc plugins.Accumulator,
 	tags map[string]string,
 	data map[string]interface{},
@@ -111,19 +76,19 @@ func (ti *TwemproxyInstance) processStat(
 	}
 	acc.AddFields("twemproxy", fields, tags)
 
-	for _, pool := range ti.Pools {
+	for _, pool := range t.Pools {
 		if poolStat, ok := data[pool]; ok {
 			if data, ok := poolStat.(map[string]interface{}); ok {
 				poolTags := copyTags(tags)
 				poolTags["pool"] = pool
-				ti.processPool(acc, poolTags, data)
+				t.processPool(acc, poolTags, data)
 			}
 		}
 	}
 }
 
 // Process pool data in Twemproxy stats
-func (ti *TwemproxyInstance) processPool(
+func (t *Twemproxy) processPool(
 	acc plugins.Accumulator,
 	tags map[string]string,
 	data map[string]interface{},
@@ -143,7 +108,7 @@ func (ti *TwemproxyInstance) processPool(
 					serverTags[key] = copyTags(tags)
 					serverTags[key]["server"] = key
 				}
-				ti.processServer(acc, serverTags[key], data)
+				t.processServer(acc, serverTags[key], data)
 			}
 		}
 	}
@@ -151,7 +116,7 @@ func (ti *TwemproxyInstance) processPool(
 }
 
 // Process backend server(redis/memcached) stats
-func (ti *TwemproxyInstance) processServer(
+func (t *Twemproxy) processServer(
 	acc plugins.Accumulator,
 	tags map[string]string,
 	data map[string]interface{},