Use non-detached mode as default for service commands

[thaJeztah]

- What I did

Commit 330a003 added a --detach=false option
to various service-related commands, with the intent to make this the default in
a future version (17.09).

This patch changes the default to use "interactive" (non-detached), allowing
users to override this by setting the --detach option.

To prevent problems when connecting to older daemon versions (17.05 and below,
see commit db60f25), the detach option is
ignored for those versions, and detach is always true.

Before this change, a warning was printed to announce the upcoming default:

$ docker service create nginx:alpine
saxiyn3pe559d753730zr0xer
Since --detach=false was not specified, tasks will be created in the background.
In a future release, --detach=false will become the default.

After this change, no warning is printed, but --detach is disabled;

$ docker service create nginx:alpine
y9jujwzozi0hwgj5yaadzliq6
overall progress: 1 out of 1 tasks
1/1: running   [==================================================>]
verify: Service converged

Setting the --detach flag makes the cli use the pre-17.06 behavior:

$ docker service create --detach nginx:alpine
280hjnzy0wzje5o56gr22a46n

Running against a 17.03 daemon, without specifying the --detach flag;

$ docker service create nginx:alpine
kqheg7ogj0kszoa34g4p73i8q

- Description for the changelog

Use interactive (non-detached) mode for `service create`, `service update`, `service rollback`, and `service scale` by default

- A picture of a cute animal (not mandatory but encouraged)

ping @vdemeester @aaronlehmann @dnephin

[vdemeester]

LGTM 🐯

[thaJeztah]

One thing I was thinking is if we should put the version-check somewhere central, and just change options.detach to true, based on that version; this would prevent possible bugs if more commands get an interactive variant.

[dnephin]

I don't think we need the version check anymore. The behaviour is client-side only, right? So even if they are running against an older daemon we should keep the same default for detach. I think we can remove the version check.

[thaJeztah]

I wasn't sure if older daemons would return the right response for the waitOnService() to work correctly; if that's not an issue then I am +1 on removing

[dnephin]

Apparently it depends on this _up-to-date=true filter which was added in 17.05, so I guess it does depend on this version still.

[thaJeztah]

Looks like there's a lint warning; I'll have a look at those;

cli/command/service/rollback.go:35:41:warning: parameter flags is unused (unparam)
cli/command/service/scale.go:58:38:warning: parameter flags is unused (unparam)

[codecov-io]

Codecov Report

Merging #525 into master will decrease coverage by <.01%.
The diff coverage is 44.44%.

@@            Coverage Diff             @@
##           master     #525      +/-   ##
==========================================
- Coverage   49.06%   49.05%   -0.01%     
==========================================
  Files         200      200              
  Lines       16407    16397      -10     
==========================================
- Hits         8050     8044       -6     
+ Misses       7938     7934       -4     
  Partials      419      419

[thaJeztah]

fixed linting error, PTAL;

diff --git a/cli/command/service/rollback.go b/cli/command/service/rollback.go
index da8c1fad..375e6d51 100644
--- a/cli/command/service/rollback.go
+++ b/cli/command/service/rollback.go
@@ -9,7 +9,6 @@ import (
        "github.com/docker/docker/api/types"
        "github.com/docker/docker/api/types/versions"
        "github.com/spf13/cobra"
-       "github.com/spf13/pflag"
 )

 func newRollbackCommand(dockerCli command.Cli) *cobra.Command {
@@ -20,7 +19,7 @@ func newRollbackCommand(dockerCli command.Cli) *cobra.Command {
                Short: "Revert changes to a service's configuration",
                Args:  cli.ExactArgs(1),
                RunE: func(cmd *cobra.Command, args []string) error {
-                       return runRollback(dockerCli, cmd.Flags(), options, args[0])
+                       return runRollback(dockerCli, options, args[0])
                },
                Tags: map[string]string{"version": "1.31"},
        }
@@ -32,7 +31,7 @@ func newRollbackCommand(dockerCli command.Cli) *cobra.Command {
        return cmd
 }

-func runRollback(dockerCli command.Cli, flags *pflag.FlagSet, options *serviceOptions, serviceID string) error {
+func runRollback(dockerCli command.Cli, options *serviceOptions, serviceID string) error {
        apiClient := dockerCli.Client()
        ctx := context.Background()

diff --git a/cli/command/service/scale.go b/cli/command/service/scale.go
index 5ab083a1..d38b01b4 100644
--- a/cli/command/service/scale.go
+++ b/cli/command/service/scale.go
@@ -13,7 +13,6 @@ import (
        "github.com/docker/docker/api/types/versions"
        "github.com/pkg/errors"
        "github.com/spf13/cobra"
-       "github.com/spf13/pflag"
 )

 type scaleOptions struct {
@@ -28,7 +27,7 @@ func newScaleCommand(dockerCli command.Cli) *cobra.Command {
                Short: "Scale one or multiple replicated services",
                Args:  scaleArgs,
                RunE: func(cmd *cobra.Command, args []string) error {
-                       return runScale(dockerCli, cmd.Flags(), options, args)
+                       return runScale(dockerCli, options, args)
                },
        }

@@ -55,7 +54,7 @@ func scaleArgs(cmd *cobra.Command, args []string) error {
        return nil
 }

-func runScale(dockerCli command.Cli, flags *pflag.FlagSet, options *scaleOptions, args []string) error {
+func runScale(dockerCli command.Cli, options *scaleOptions, args []string) error {
        var errs []string
        var serviceIDs []string
        ctx := context.Background()

[dnephin]

LGTM