From 05426c80d991ab31593a47dba166ff41ca23e374 Mon Sep 17 00:00:00 2001
From: Yong Tang <yong.tang.github@outlook.com>
Date: Wed, 7 Dec 2016 07:38:18 -0800
Subject: [PATCH] Fix `docker plugin inspect <unkown object>` issue on Windows

This fix is a follow up for comment:
https://github.com/docker/docker/pull/29186/files#r91277345

While #29186 addresses the issue of `docker inspect <unknown object>`
on Windows, it actually makes `docker plugin inspect <unknown object>`
out `object not found` on Windows as well. This is actually misleading
as plugin is not supported on Windows.

This fix reverted the change in #29186 while at the same time,
checks `not supported` in `docker inspect <unknown object>` so that
- `docker plugin inspect <unknown object>` returns `not supported` on Windows
- `docker inspect <unknown object>` returns `not found` on Windows

This fix is related to #29186 and #29185.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
(cherry picked from commit 0b3c10ac4ddfe3655bac080440a8553269f2307f)
---
 cli/command/system/inspect.go              |  6 +++++-
 integration-cli/docker_cli_plugins_test.go | 11 +++++++++++
 plugin/backend_unsupported.go              |  6 +-----
 3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/cli/command/system/inspect.go b/cli/command/system/inspect.go
index dee4efcfec..f7172ae3c6 100644
--- a/cli/command/system/inspect.go
+++ b/cli/command/system/inspect.go
@@ -121,6 +121,10 @@ func inspectAll(ctx context.Context, dockerCli *command.DockerCli, getSize bool,
 		return strings.Contains(err.Error(), "This node is not a swarm manager")
 	}
 
+	isErrNotSupported := func(err error) bool {
+		return strings.Contains(err.Error(), "not supported")
+	}
+
 	return func(ref string) (interface{}, []byte, error) {
 		for _, inspectData := range inspectAutodetect {
 			if typeConstraint != "" && inspectData.ObjectType != typeConstraint {
@@ -128,7 +132,7 @@ func inspectAll(ctx context.Context, dockerCli *command.DockerCli, getSize bool,
 			}
 			v, raw, err := inspectData.ObjectInspector(ref)
 			if err != nil {
-				if typeConstraint == "" && (apiclient.IsErrNotFound(err) || isErrNotSwarmManager(err)) {
+				if typeConstraint == "" && (apiclient.IsErrNotFound(err) || isErrNotSwarmManager(err) || isErrNotSupported(err)) {
 					continue
 				}
 				return v, raw, err
diff --git a/integration-cli/docker_cli_plugins_test.go b/integration-cli/docker_cli_plugins_test.go
index cfc02518e4..385a58337d 100644
--- a/integration-cli/docker_cli_plugins_test.go
+++ b/integration-cli/docker_cli_plugins_test.go
@@ -251,3 +251,14 @@ func (s *DockerSuite) TestPluginInspect(c *check.C) {
 	_, _, err = dockerCmdWithError("plugin", "inspect", "-f", "{{.Id}}", id[:5])
 	c.Assert(err, checker.NotNil)
 }
+
+// Test case for https://github.com/docker/docker/pull/29186#discussion_r91277345
+func (s *DockerSuite) TestPluginInspectOnWindows(c *check.C) {
+	// This test should work on Windows only
+	testRequires(c, DaemonIsWindows)
+
+	out, _, err := dockerCmdWithError("plugin", "inspect", "foobar")
+	c.Assert(err, checker.NotNil)
+	c.Assert(out, checker.Contains, "plugins are not supported on this platform")
+	c.Assert(err.Error(), checker.Contains, "plugins are not supported on this platform")
+}
diff --git a/plugin/backend_unsupported.go b/plugin/backend_unsupported.go
index 2d4b365faf..0364f4876e 100644
--- a/plugin/backend_unsupported.go
+++ b/plugin/backend_unsupported.go
@@ -4,7 +4,6 @@ package plugin
 
 import (
 	"errors"
-	"fmt"
 	"io"
 	"net/http"
 
@@ -26,10 +25,7 @@ func (pm *Manager) Enable(name string, config *types.PluginEnableConfig) error {
 
 // Inspect examines a plugin config
 func (pm *Manager) Inspect(refOrID string) (tp types.Plugin, err error) {
-	// Even though plugin is not supported, we still want to return `not found`
-	// error so that `docker inspect` (without `--type` specified) returns correct
-	// `not found` message
-	return tp, fmt.Errorf("no such plugin name or ID associated with %q", refOrID)
+	return tp, errNotSupported
 }
 
 // Privileges pulls a plugin config and computes the privileges required to install it.