initial commit (#1)

.gitignore

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+.idea/
+
+dist/

.goreleaser.yaml

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+before:
+  hooks:
+    - go mod tidy
+builds:
+  - main: ./cmd/
+    env:
+      - CGO_ENABLED=0
+    goos:
+      - linux
+      - windows
+      - darwin
+
+archives:
+  - format: tar.gz
+    # this name template makes the OS and Arch compatible with the results of uname.
+    name_template: >-
+      {{ .ProjectName }}_
+      {{- title .Os }}_
+      {{- if eq .Arch "amd64" }}x86_64
+      {{- else if eq .Arch "386" }}i386
+      {{- else }}{{ .Arch }}{{ end }}
+      {{- if .Arm }}v{{ .Arm }}{{ end }}
+    # use zip for windows archives
+    format_overrides:
+    - goos: windows
+      format: zip
+checksum:
+  name_template: 'checksums.txt'
+snapshot:
+  name_template: "{{ incpatch .Version }}-next"
+changelog:
+  sort: asc
+  filters:
+    exclude:
+      - '^docs:'
+      - '^test:'

.tool-versions

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+golang 1.20

README.md

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+# kubectl pprof plugin
+
+A simple kubectl plugin to collect Go pprof profiles from pods that 
+expose the ["net/http/pprof"](https://pkg.go.dev/net/http/pprof) endpoints on a local port.
+
+The plugin will port-forward to the specified pod and write the pprof profile to the filesystem
+to be analyze with `go tool pprof`.
+
+## Installing
+
+1. Download the binary from the GH release
+2. Move the `kubectl-pprof` binary to anywhere in your `$PATH`
+3. Run `kubectl pprof -h` to validate the plugin is working
+
+## Example usage
+
+### Collecting a CPU profile
+
+```bash
+kubectl pprof <pod> --port 8080 -n <namespace> --profile cpu
+```
+
+### Collecting a heap profile for 30 seconds
+
+```bash
+kubectl pprof <pod> --port 8080 -n <namespace> --profile heap --seconds 30 --output /tmp/
+```
+
+### Pass a profile directly to `go tool pprof` (suppress output with `-q`)
+
+```bash
+kubectl pprof <pod> --port 8080 -n <namespace> --profile cpu -q | xargs go tool pprof -http=:8080
+```

cmd/pprof/pprof.go

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+package pprof
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"os"
+	"path"
+	"runtime/pprof"
+	"time"
+
+	"github.com/spf13/cobra"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/cli-runtime/pkg/genericiooptions"
+	"k8s.io/client-go/rest"
+
+	"github.com/cbuto/kubectl-pprof/internal/portforward"
+	"github.com/cbuto/kubectl-pprof/internal/pprofgetter"
+)
+
+var pprofExample = `
+	# collect a heap profile a pod
+	%[1]s pprof <pod name> --profile heap --seconds 10
+	
+	# collect a cpu profile and output profile to /tmp/
+	%[1]s pprof <pod name> --port 8080 -n <namespace> --profile cpu --output /tmp/ --seconds 30
+
+	# pass a profile directly to go tool pprof (suppress output with -q)
+	%[1]s pprof <pod> --port 8080 -n <namespace> --profile cpu -q | xargs go tool pprof -http=:8080
+
+`
+
+const (
+	DefaultProfileSeconds = 10
+	DefaultPProfPort      = 8080
+)
+
+type pprofCmdOptions struct {
+	genericiooptions.IOStreams
+	restConfig  *rest.Config
+	configFlags *genericclioptions.ConfigFlags
+	profile     string
+	seconds     int
+	port        int
+	outDir      string
+	namespace   string
+	pod         string
+	quiet       bool
+}
+
+func newPProfOptions(streams genericiooptions.IOStreams) *pprofCmdOptions {
+	return &pprofCmdOptions{
+		configFlags: genericclioptions.NewConfigFlags(true),
+		IOStreams:   streams,
+	}
+}
+
+func NewPProfCmd(streams genericiooptions.IOStreams) *cobra.Command {
+	opts := newPProfOptions(streams)
+
+	cmd := &cobra.Command{
+		Use:          "pprof [pod] [flags]",
+		Short:        "Collects the specified pprof profile from a pod",
+		Example:      fmt.Sprintf(pprofExample, "kubectl"),
+		SilenceUsage: true,
+		RunE: func(c *cobra.Command, args []string) error {
+			if err := opts.Complete(c, args); err != nil {
+				return err
+			}
+			if err := opts.Validate(); err != nil {
+				return err
+			}
+			if err := opts.Run(); err != nil {
+				return err
+			}
+
+			return nil
+		},
+	}
+
+	cmd.Flags().BoolVarP(&opts.quiet, "quiet", "q", false, "suppresses output and only prints the output file")
+	cmd.Flags().StringVar(&opts.profile,
+		"profile",
+		"cpu", "type of profile to collect (heap, cpu, block, goroutine, mutex, or threadcreate)")
+	cmd.Flags().StringVar(&opts.outDir, "output", "./", "path to a directory to write the profile")
+	cmd.Flags().IntVar(&opts.seconds, "seconds", DefaultProfileSeconds, "amount of seconds to collect the profile")
+	cmd.Flags().IntVar(&opts.port, "port", DefaultPProfPort, "pprof port")
+
+	opts.configFlags.AddFlags(cmd.Flags())
+
+	return cmd
+}
+
+func (o *pprofCmdOptions) Complete(cmd *cobra.Command, args []string) error {
+	var err error
+	o.namespace, _, err = o.configFlags.ToRawKubeConfigLoader().Namespace()
+
+	if err != nil {
+		return fmt.Errorf("failed to get namespace from config: %w", err)
+	}
+
+	if len(args) != 1 {
+		return fmt.Errorf("invalid number of arguments, use --help to see example usage")
+	}
+
+	o.pod = args[0]
+	o.restConfig, err = o.configFlags.ToRESTConfig()
+
+	if err != nil {
+		return fmt.Errorf("failed to get REST config: %w", err)
+	}
+
+	return nil
+}
+
+func (o *pprofCmdOptions) Validate() error {
+	if o.profile == "" {
+		return fmt.Errorf("must select type of profile to collect")
+	}
+
+	if o.profile != "cpu" {
+		profile := pprof.Lookup(o.profile)
+		if profile == nil {
+			return fmt.Errorf("unknown profile: %s", o.profile)
+		}
+	}
+
+	fileInfo, err := os.Stat(o.outDir)
+
+	if err != nil {
+		return fmt.Errorf("failed to check if --output is a dir: %w", err)
+	}
+
+	if !fileInfo.IsDir() {
+		return fmt.Errorf("--output flag must be set to a directory: %s", o.outDir)
+	}
+
+	return nil
+}
+
+func (o *pprofCmdOptions) Run() error {
+	var err error
+
+	ctx := context.TODO()
+
+	out, errOut := o.IOStreams.Out, o.IOStreams.ErrOut
+	if o.quiet {
+		out, errOut = nil, nil
+	}
+
+	portforwarder, err := portforward.NewPortForward(
+		portforward.WithRESTConfig(o.restConfig),
+		portforward.WithOutput(out, errOut))
+	if err != nil {
+		return fmt.Errorf("failed to get port-forwarder: %w", err)
+	}
+
+	localPort, stopCh, err := portforwarder.PortForward(ctx, o.namespace, o.pod, o.port)
+
+	if err != nil {
+		return fmt.Errorf("port-forwarding failed: %w", err)
+	}
+
+	defer close(stopCh)
+
+	if !o.quiet {
+		_, err = o.IOStreams.Out.Write([]byte(fmt.Sprintf("collecting profile from %s (for %d secs)...\n", o.pod, o.seconds)))
+		if err != nil {
+			return fmt.Errorf("failed to write to output: %w", err)
+		}
+	}
+
+	outFilePath := path.Join(o.outDir, fmt.Sprintf("%s_%s_%d.out", o.pod, o.profile, time.Now().Unix()))
+	pprofHostURL := &url.URL{
+		Scheme: "http",
+		Host:   fmt.Sprintf("localhost:%d", localPort),
+	}
+
+	getter, err := pprofgetter.NewPProfGetter(pprofgetter.WithHostURL(pprofHostURL))
+	if err != nil {
+		return fmt.Errorf("failed to build pprof getter: %w", err)
+	}
+
+	err = getter.Get(ctx, o.profile, o.seconds, outFilePath)
+	if err != nil {
+		return fmt.Errorf("failed to collect profile: %w", err)
+	}
+
+	_, err = o.IOStreams.Out.Write([]byte(fmt.Sprintf("%s\n", outFilePath)))
+	if err != nil {
+		return fmt.Errorf("failed to output profile filename: %w", err)
+	}
+
+	return nil
+}

cmd/root.go

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+package main
+
+import (
+	"os"
+
+	"github.com/cbuto/kubectl-pprof/cmd/pprof"
+
+	"github.com/spf13/pflag"
+	"k8s.io/cli-runtime/pkg/genericiooptions"
+)
+
+func main() {
+	flags := pflag.NewFlagSet("kubectl-pprof", pflag.ExitOnError)
+	pflag.CommandLine = flags
+
+	root := pprof.NewPProfCmd(genericiooptions.IOStreams{In: os.Stdin, Out: os.Stdout, ErrOut: os.Stderr})
+	if err := root.Execute(); err != nil {
+		os.Exit(1)
+	}
+}

go.mod

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+module github.com/cbuto/kubectl-pprof
+
+go 1.20
+
+require (
+	github.com/spf13/cobra v1.7.0
+	github.com/spf13/pflag v1.0.5
+	github.com/stretchr/testify v1.8.2
+	k8s.io/cli-runtime v0.0.0-20230718062906-448da40f6f16
+	k8s.io/client-go v0.0.0-20230718055620-74c18d3a4044
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/emicklei/go-restful/v3 v3.9.0 // indirect
+	github.com/evanphx/json-patch v5.6.0+incompatible // indirect
+	github.com/go-errors/errors v1.4.2 // indirect
+	github.com/go-logr/logr v1.2.4 // indirect
+	github.com/go-openapi/jsonpointer v0.19.6 // indirect
+	github.com/go-openapi/jsonreference v0.20.2 // indirect
+	github.com/go-openapi/swag v0.22.3 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/google/btree v1.0.1 // indirect
+	github.com/google/gnostic-models v0.6.8 // indirect
+	github.com/google/go-cmp v0.5.9 // indirect
+	github.com/google/gofuzz v1.2.0 // indirect
+	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7 // indirect
+	github.com/imdario/mergo v0.3.6 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/moby/spdystream v0.2.0 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/monochromegane/go-gitignore v0.0.0-20200626010858-205db1a8cc00 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/xlab/treeprint v1.2.0 // indirect
+	go.starlark.net v0.0.0-20230525235612-a134d8f9ddca // indirect
+	golang.org/x/net v0.12.0 // indirect
+	golang.org/x/oauth2 v0.8.0 // indirect
+	golang.org/x/sync v0.2.0 // indirect
+	golang.org/x/sys v0.10.0 // indirect
+	golang.org/x/term v0.10.0 // indirect
+	golang.org/x/text v0.11.0 // indirect
+	golang.org/x/time v0.3.0 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.30.0 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/api v0.0.0-20230718054858-1b0ec3bb3296 // indirect
+	k8s.io/apimachinery v0.0.0-20230718054246-5cb236977966 // indirect
+	k8s.io/klog/v2 v2.100.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20230717233707-2695361300d9 // indirect
+	k8s.io/utils v0.0.0-20230406110748-d93618cff8a2 // indirect
+	sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd // indirect
+	sigs.k8s.io/kustomize/api v0.13.5-0.20230601165947-6ce0bf390ce3 // indirect
+	sigs.k8s.io/kustomize/kyaml v0.14.3-0.20230601165947-6ce0bf390ce3 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.2.3 // indirect
+	sigs.k8s.io/yaml v1.3.0 // indirect
+)