Fix err race condition and partial failure issues

closes #1439
closes #1440
closes #1441
closes #1442
closes #1443
closes #1444
closes #1445

CHANGELOG.md

@@ -1,5 +1,11 @@
 ## v1.0 [unreleased]
 
+### Features
+
+### Bugfixes
+
+- [#1519](https://github.com/influxdata/telegraf/pull/1519): Fix error race conditions and partial failures.
+
 ## v1.0 beta 3 [2016-07-18]
 
 ### Release Notes

plugins/inputs/dns_query/dns_query.go

@@ -3,12 +3,14 @@ package dns_query
 import (
 	"errors"
 	"fmt"
-	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/plugins/inputs"
 	"github.com/miekg/dns"
 	"net"
 	"strconv"
 	"time"
+
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
+	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
 type DnsQuery struct {
@@ -55,12 +57,12 @@ func (d *DnsQuery) Description() string {
 }
 func (d *DnsQuery) Gather(acc telegraf.Accumulator) error {
 	d.setDefaultValues()
+
+	errChan := errchan.New(len(d.Domains) * len(d.Servers))
 	for _, domain := range d.Domains {
 		for _, server := range d.Servers {
 			dnsQueryTime, err := d.getDnsQueryTime(domain, server)
-			if err != nil {
-				return err
-			}
+			errChan.C <- err
 			tags := map[string]string{
 				"server":      server,
 				"domain":      domain,
@@ -72,7 +74,7 @@ func (d *DnsQuery) Gather(acc telegraf.Accumulator) error {
 		}
 	}
 
-	return nil
+	return errChan.Error()
 }
 
 func (d *DnsQuery) setDefaultValues() {

plugins/inputs/dovecot/dovecot.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
@@ -51,7 +52,6 @@ const defaultPort = "24242"
 
 // Reads stats from all configured servers.
 func (d *Dovecot) Gather(acc telegraf.Accumulator) error {
-
 	if !validQuery[d.Type] {
 		return fmt.Errorf("Error: %s is not a valid query type\n",
 			d.Type)
@@ -61,31 +61,27 @@ func (d *Dovecot) Gather(acc telegraf.Accumulator) error {
 		d.Servers = append(d.Servers, "127.0.0.1:24242")
 	}
 
-	var wg sync.WaitGroup
-
-	var outerr error
-
 	if len(d.Filters) <= 0 {
 		d.Filters = append(d.Filters, "")
 	}
 
-	for _, serv := range d.Servers {
+	var wg sync.WaitGroup
+	errChan := errchan.New(len(d.Servers) * len(d.Filters))
+	for _, server := range d.Servers {
 		for _, filter := range d.Filters {
 			wg.Add(1)
-			go func(serv string, filter string) {
+			go func(s string, f string) {
 				defer wg.Done()
-				outerr = d.gatherServer(serv, acc, d.Type, filter)
-			}(serv, filter)
+				errChan.C <- d.gatherServer(s, acc, d.Type, f)
+			}(server, filter)
 		}
 	}
 
 	wg.Wait()
-
-	return outerr
+	return errChan.Error()
 }
 
 func (d *Dovecot) gatherServer(addr string, acc telegraf.Accumulator, qtype string, filter string) error {
-
 	_, _, err := net.SplitHostPort(addr)
 	if err != nil {
 		return fmt.Errorf("Error: %s on url %s\n", err, addr)

plugins/inputs/memcached/memcached.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
@@ -73,19 +74,16 @@ func (m *Memcached) Gather(acc telegraf.Accumulator) error {
 		return m.gatherServer(":11211", false, acc)
 	}
 
+	errChan := errchan.New(len(m.Servers) + len(m.UnixSockets))
 	for _, serverAddress := range m.Servers {
-		if err := m.gatherServer(serverAddress, false, acc); err != nil {
-			return err
-		}
+		errChan.C <- m.gatherServer(serverAddress, false, acc)
 	}
 
 	for _, unixAddress := range m.UnixSockets {
-		if err := m.gatherServer(unixAddress, true, acc); err != nil {
-			return err
-		}
+		errChan.C <- m.gatherServer(unixAddress, true, acc)
 	}
 
-	return nil
+	return errChan.Error()
 }
 
 func (m *Memcached) gatherServer(

plugins/inputs/mongodb/mongodb.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/plugins/inputs"
 	"gopkg.in/mgo.v2"
 )
@@ -55,9 +56,7 @@ func (m *MongoDB) Gather(acc telegraf.Accumulator) error {
 	}
 
 	var wg sync.WaitGroup
-
-	var outerr error
-
+	errChan := errchan.New(len(m.Servers))
 	for _, serv := range m.Servers {
 		u, err := url.Parse(serv)
 		if err != nil {
@@ -73,13 +72,12 @@ func (m *MongoDB) Gather(acc telegraf.Accumulator) error {
 		wg.Add(1)
 		go func(srv *Server) {
 			defer wg.Done()
-			outerr = m.gatherServer(srv, acc)
+			errChan.C <- m.gatherServer(srv, acc)
 		}(m.getMongoServer(u))
 	}
 
 	wg.Wait()
-
-	return outerr
+	return errChan.Error()
 }
 
 func (m *MongoDB) getMongoServer(url *url.URL) *Server {

plugins/inputs/mysql/mysql.go

@@ -7,10 +7,12 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	_ "github.com/go-sql-driver/mysql"
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
@@ -118,26 +120,27 @@ func (m *Mysql) InitMysql() {
 
 func (m *Mysql) Gather(acc telegraf.Accumulator) error {
 	if len(m.Servers) == 0 {
-		// if we can't get stats in this case, thats fine, don't report
-		// an error.
-		m.gatherServer(localhost, acc)
-		return nil
+		// default to localhost if nothing specified.
+		return m.gatherServer(localhost, acc)
 	}
-
 	// Initialise additional query intervals
 	if !initDone {
 		m.InitMysql()
 	}
+	var wg sync.WaitGroup
+	errChan := errchan.New(len(m.Servers))
 
 	// Loop through each server and collect metrics
-	for _, serv := range m.Servers {
-		err := m.gatherServer(serv, acc)
-		if err != nil {
-			return err
-		}
+	for _, server := range m.Servers {
+		wg.Add(1)
+		go func(s string) {
+			defer wg.Done()
+			errChan.C <- m.gatherServer(s, acc)
+		}(server)
 	}
 
-	return nil
+	wg.Wait()
+	return errChan.Error()
 }
 
 type mapping struct {

plugins/inputs/mysql/mysql_test.go

@@ -20,7 +20,6 @@ func TestMysqlDefaultsToLocal(t *testing.T) {
 	}
 
 	var acc testutil.Accumulator
-
 	err := m.Gather(&acc)
 	require.NoError(t, err)
 

plugins/inputs/nginx/nginx.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
@@ -34,7 +35,7 @@ func (n *Nginx) Description() string {
 
 func (n *Nginx) Gather(acc telegraf.Accumulator) error {
 	var wg sync.WaitGroup
-	var outerr error
+	errChan := errchan.New(len(n.Urls))
 
 	for _, u := range n.Urls {
 		addr, err := url.Parse(u)
@@ -45,13 +46,12 @@ func (n *Nginx) Gather(acc telegraf.Accumulator) error {
 		wg.Add(1)
 		go func(addr *url.URL) {
 			defer wg.Done()
-			outerr = n.gatherUrl(addr, acc)
+			errChan.C <- n.gatherUrl(addr, acc)
 		}(addr)
 	}
 
 	wg.Wait()
-
-	return outerr
+	return errChan.Error()
 }
 
 var tr = &http.Transport{

plugins/inputs/nsq/nsq.go

@@ -32,6 +32,7 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
@@ -65,19 +66,17 @@ func (n *NSQ) Description() string {
 
 func (n *NSQ) Gather(acc telegraf.Accumulator) error {
 	var wg sync.WaitGroup
-	var outerr error
-
+	errChan := errchan.New(len(n.Endpoints))
 	for _, e := range n.Endpoints {
 		wg.Add(1)
 		go func(e string) {
 			defer wg.Done()
-			outerr = n.gatherEndpoint(e, acc)
+			errChan.C <- n.gatherEndpoint(e, acc)
 		}(e)
 	}
 
 	wg.Wait()
-
-	return outerr
+	return errChan.Error()
 }
 
 var tr = &http.Transport{