toolshed/docker-cli
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

cli/flags: add "hostVar" to handle --host / -H as a single string

Browse Source 
hostVar is used for the '--host' / '-H' flag to set [ClientOptions.Hosts].
The [ClientOptions.Hosts] field is a slice because it was originally shared
with the daemon config. However, the CLI only allows for a single host to
be specified.

hostVar presents itself as a "string", but stores the value in a string
slice. It produces an error when trying to set multiple values, matching
the check in [getServerHost].

[getServerHost]: https://github.com/docker/cli/blob/7eab668982645def1cd46fe1b60894cba6fd17a4/cli/command/cli.go#L542-L551

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit f14eeeb361)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This commit is contained in:
Sebastiaan van Stijn
2025-08-16 19:10:58 +02:00
parent ff42ff9f06
commit 7091e8bea4
3 changed files with 50 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files
cli/flags/options.go
+35 -1
View File
@@ -1,6 +1,7 @@
package flags
import (
"errors"
"fmt"
"os"
"path/filepath"
@@ -53,6 +54,39 @@ var (
dockerTLS = os.Getenv(EnvEnableTLS) != ""
)
// hostVar is used for the '--host' / '-H' flag to set [ClientOptions.Hosts].
// The [ClientOptions.Hosts] field is a slice because it was originally shared
// with the daemon config. However, the CLI only allows for a single host to
// be specified.
//
// hostVar presents itself as a "string", but stores the value in a string
// slice. It produces an error when trying to set multiple values, matching
// the check in [getServerHost].
//
// [getServerHost]: https://github.com/docker/cli/blob/7eab668982645def1cd46fe1b60894cba6fd17a4/cli/command/cli.go#L542-L551
type hostVar struct {
dst *[]string
set bool
}
func (h *hostVar) String() string {
if h.dst == nil || len(*h.dst) == 0 {
return ""
}
return (*h.dst)[0]
}
func (h *hostVar) Set(s string) error {
if h.set {
return errors.New("specify only one -H")
}
*h.dst = []string{s}
h.set = true
return nil
}
func (*hostVar) Type() string { return "string" }
// ClientOptions are the options used to configure the client cli.
type ClientOptions struct {
Debug bool
@@ -95,7 +129,7 @@ func (o *ClientOptions) InstallFlags(flags *pflag.FlagSet) {
// TODO(thaJeztah): show the default host.
// TODO(thaJeztah): this should be a string, not an "array" as we only allow a single host.
flags.StringArrayVarP(&o.Hosts, "host", "H", nil, "Daemon socket to connect to")
flags.VarP(&hostVar{dst: &o.Hosts}, "host", "H", "Daemon socket to connect to")
flags.StringVarP(&o.Context, "context", "c", "",
`Name of the context to use to connect to the daemon (overrides `+client.EnvOverrideHost+` env var and default context set with "docker context use")`)
}
docs/reference/commandline/docker.md
+12 -12
View File
@@ -69,18 +69,18 @@ The base command for the Docker CLI.
### Options
| Name | Type | Default | Description |
|:---------------------------------|:--------------|:-------------------------|:--------------------------------------------------------------------------------------------------------------------------------------|
| `--config` | `string` | `/root/.docker` | Location of client config files |
| `-c`, `--context` | `string` | | Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with `docker context use`) |
| `-D`, `--debug` | `bool` | | Enable debug mode |
| [`-H`](#host), [`--host`](#host) | `stringArray` | | Daemon socket to connect to |
| `-l`, `--log-level` | `string` | `info` | Set the logging level (`debug`, `info`, `warn`, `error`, `fatal`) |
| `--tls` | `bool` | | Use TLS; implied by --tlsverify |
| `--tlscacert` | `string` | `/root/.docker/ca.pem` | Trust certs signed only by this CA |
| `--tlscert` | `string` | `/root/.docker/cert.pem` | Path to TLS certificate file |
| `--tlskey` | `string` | `/root/.docker/key.pem` | Path to TLS key file |
| `--tlsverify` | `bool` | | Use TLS and verify the remote |
| Name | Type | Default | Description |
|:---------------------------------|:---------|:-------------------------|:--------------------------------------------------------------------------------------------------------------------------------------|
| `--config` | `string` | `/root/.docker` | Location of client config files |
| `-c`, `--context` | `string` | | Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with `docker context use`) |
| `-D`, `--debug` | `bool` | | Enable debug mode |
| [`-H`](#host), [`--host`](#host) | `string` | | Daemon socket to connect to |
| `-l`, `--log-level` | `string` | `info` | Set the logging level (`debug`, `info`, `warn`, `error`, `fatal`) |
| `--tls` | `bool` | | Use TLS; implied by --tlsverify |
| `--tlscacert` | `string` | `/root/.docker/ca.pem` | Trust certs signed only by this CA |
| `--tlscert` | `string` | `/root/.docker/cert.pem` | Path to TLS certificate file |
| `--tlskey` | `string` | `/root/.docker/key.pem` | Path to TLS key file |
| `--tlsverify` | `bool` | | Use TLS and verify the remote |
<!---MARKER_GEN_END-->
e2e/cli-plugins/flags_test.go
+3 -2
View File
@@ -1,6 +1,7 @@
package cliplugins
import (
"fmt"
"os"
"testing"
@@ -91,9 +92,9 @@ func TestGlobalArgsOnlyParsedOnce(t *testing.T) {
// This is checking the precondition wrt -H mentioned in the function comment
name: "fails-if-H-used-twice",
args: []string{"-H", dh, "-H", dh, "version", "-f", "{{.Client.Version}}"},
expectedExitCode: 1,
expectedExitCode: 125,
expectedOut: icmd.None,
expectedErr: "Specify only one -H",
expectedErr: fmt.Sprintf(`invalid argument %q for "-H, --host" flag: specify only one -H`, dh),
},
{
name: "builtin",