refactor: use an error group to simplify parallel retrieval of scheduler

This makes the code a bit simpler to read and more idiomatic

plugins/app-json/go.sum

@@ -6,3 +6,5 @@ github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 h1:Z9n2FFNU
 github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51/go.mod h1:CzGEWj7cYgsdH8dAjBGEr58BoE7ScuLd+fwFZ44+/x8=
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1XjNtTFGCwSM6OmFJblU4ld4gACoJsbadJg=
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/apps/go.sum

@@ -6,3 +6,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/buildpacks/go.sum

@@ -6,3 +6,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/common/common.go

@@ -1,6 +1,7 @@
 package common
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -11,10 +12,10 @@ import (
 	"sort"
 	"strconv"
 	"strings"
-	"sync"
 	"unicode"
 
 	"github.com/ryanuber/columnize"
+	"golang.org/x/sync/errgroup"
 )
 
 type errfunc func() error
@@ -68,23 +69,20 @@ func GetAppScheduler(appName string) string {
 	appScheduler := ""
 	globalScheduler := ""
 
-	var wg sync.WaitGroup
+	ctx := context.Background()
+	errs, ctx := errgroup.WithContext(ctx)
 
 	if appName != "--global" {
-		wg.Add(1)
+		errs.Go(func() error {
-		go func() {
-			defer wg.Done()
 			appScheduler = getAppScheduler(appName)
-		}()
+			return nil
+		})
 	}
-
+	errs.Go(func() error {
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
 		globalScheduler = GetGlobalScheduler()
-	}()
+		return nil
-
+	})
-	wg.Wait()
+	errs.Wait()
 
 	if appScheduler == "" {
 		appScheduler = globalScheduler

plugins/common/go.mod

@@ -6,4 +6,5 @@ require (
 	github.com/codegangsta/inject v0.0.0-20150114235600-33e0aa1cb7c0 // indirect
 	github.com/codeskyblue/go-sh v0.0.0-20190412065543-76bd3d59ff27
 	github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3
+	golang.org/x/sync v0.0.0-20201207232520-09787c993a3a
 )

plugins/common/go.sum

@@ -4,3 +4,5 @@ github.com/codeskyblue/go-sh v0.0.0-20190412065543-76bd3d59ff27 h1:HHUr4P/aKh4qu
 github.com/codeskyblue/go-sh v0.0.0-20190412065543-76bd3d59ff27/go.mod h1:VQx0hjo2oUeQkQUET7wRwradO6f+fN5jzXgB/zROxxE=
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1XjNtTFGCwSM6OmFJblU4ld4gACoJsbadJg=
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/config/go.sum

@@ -8,3 +8,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/logs/go.sum

@@ -6,3 +6,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/network/go.sum

@@ -8,3 +8,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/proxy/go.sum

@@ -8,3 +8,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/ps/go.sum

@@ -12,3 +12,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/repo/go.sum

@@ -8,3 +8,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

plugins/resource/go.sum

@@ -6,3 +6,5 @@ github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3 h1:utdYOikI1X
 github.com/ryanuber/columnize v1.1.2-0.20190319233515-9e6335e58db3/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a h1:DcqTD9SDLc+1P/r1EmRBwnVsrOwW+kk2vWf9n+1sGhs=
+golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=