deprecate pkg/stdcopy, move to api/stdcopy

The stdcopy package is used to produce and read multiplexed streams for
"attach" and "logs". It is used both by the API server (to produce), and
the client (to read / de-multiplex).

Move it to the api package, so that it can be included in the api module.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

pkg/stdcopy/stdcopy.go api/stdcopy/stdcopy.gopkg/stdcopy/stdcopy.go renamed to api/stdcopy/stdcopy.go

@@ -31,7 +31,7 @@ import (
 // SIZE1, SIZE2, SIZE3, and SIZE4 are four bytes of uint32 encoded as big endian.
 // This is the size of OUTPUT.
 //
-// You can use github.com/docker/docker/pkg/stdcopy.StdCopy to demultiplex this
+// You can use github.com/moby/moby/api/stdcopy.StdCopy to demultiplex this
 // stream.
 func (cli *Client) ContainerAttach(ctx context.Context, containerID string, options container.AttachOptions) (types.HijackedResponse, error) {
 	containerID, err := trimID("container", containerID)

pkg/stdcopy/stdcopy_test.go api/stdcopy/stdcopy_test.gopkg/stdcopy/stdcopy_test.go renamed to api/stdcopy/stdcopy_test.go

@@ -68,7 +68,7 @@ func (cli *Client) ContainerExecStart(ctx context.Context, execID string, config
 //   - If the container is *not* using a TTY, streams for stdout and stderr are
 //     multiplexed.
 //
-// You can use [github.com/docker/docker/pkg/stdcopy.StdCopy] to demultiplex this
+// You can use [github.com/moby/moby/api/stdcopy.StdCopy] to demultiplex this
 // stream. Refer to [Client.ContainerAttach] for details about the multiplexed
 // stream.
 func (cli *Client) ContainerExecAttach(ctx context.Context, execID string, config container.ExecAttachOptions) (types.HijackedResponse, error) {

client/container_attach.go

@@ -31,7 +31,7 @@ import (
 // SIZE1, SIZE2, SIZE3, and SIZE4 are four bytes of uint32 encoded as big endian.
 // This is the size of OUTPUT.
 //
-// You can use github.com/docker/docker/pkg/stdcopy.StdCopy to demultiplex this
+// You can use github.com/moby/moby/api/stdcopy.StdCopy to demultiplex this
 // stream.
 func (cli *Client) ContainerLogs(ctx context.Context, containerID string, options container.LogsOptions) (io.ReadCloser, error) {
 	containerID, err := trimID("container", containerID)

client/container_exec.go

@@ -10,7 +10,7 @@ import (
 	"github.com/docker/docker/daemon/internal/stream"
 	"github.com/docker/docker/daemon/logger"
 	"github.com/docker/docker/errdefs"
-	"github.com/docker/docker/pkg/stdcopy"
+	"github.com/moby/moby/api/stdcopy"
 	"github.com/moby/moby/api/types/backend"
 	containertypes "github.com/moby/moby/api/types/container"
 	"github.com/moby/moby/api/types/events"

client/container_logs.go

@@ -10,7 +10,7 @@ import (
 
 	"github.com/docker/docker/pkg/ioutils"
 	"github.com/docker/docker/pkg/jsonmessage"
-	"github.com/docker/docker/pkg/stdcopy"
+	"github.com/moby/moby/api/stdcopy"
 	"github.com/moby/moby/api/types/backend"
 	"github.com/moby/moby/api/types/container"
 )

daemon/attach.go

@@ -9,7 +9,7 @@ import (
 	"github.com/containerd/log"
 	"github.com/docker/docker/daemon/server/httputils"
 	"github.com/docker/docker/errdefs"
-	"github.com/docker/docker/pkg/stdcopy"
+	"github.com/moby/moby/api/stdcopy"
 	"github.com/moby/moby/api/types"
 	"github.com/moby/moby/api/types/backend"
 	"github.com/moby/moby/api/types/container"

daemon/server/httputils/write_log_stream.go

@@ -256,6 +256,15 @@ Function Validate-PkgImports($headCommit, $upstreamCommit) {
     $files=@(); $files = Invoke-Expression "git diff $upstreamCommit...$headCommit --diff-filter=ACMR --name-only -- `'pkg\*.go`'"
     $badFiles=@(); $files | ForEach-Object{
         $file=$_
+
+        if ($file -like "pkg\stdcopy\*") {
+            # Temporarily allow pkg/stdcopy to import "github.com/moby/moby/api/stdcopy",
+            # because it's an alias for backward-compatibility.
+            #
+            # TODO(thaJeztah): remove once "github.com/docker/docker/pkg/stdcopy" is removed.
+            return
+        }
+
         # For the current changed file, get its list of dependencies, sorted and uniqued.
         $imports = Invoke-Expression "go list -e -f `'{{ .Deps }}`' $file"
         if ($LASTEXITCODE -ne 0) { Throw "Failed go list for dependencies on $file" }

daemon/server/router/container/exec.go

@@ -10,6 +10,16 @@ unset IFS
 
 badFiles=()
 for f in "${files[@]}"; do
+	case "$f" in
+		pkg/stdcopy/*)
+			# Temporarily allow pkg/stdcopy to import "github.com/moby/moby/api/stdcopy",
+			# because it's an alias for backward-compatibility.
+			#
+			# TODO(thaJeztah): remove once "github.com/docker/docker/pkg/stdcopy" is removed.
+			continue
+			;;
+	esac
+
 	IFS=$'\n'
 	badImports=($(go list -e -f '{{ join .Deps "\n" }}' "$f" | sort -u \
 		| grep -vE '^github.com/docker/docker/pkg/' \