Add support for multible registrys (#23)

if normal settings `registry`, `username`... is set

that's used as default, else first logins entry is used.

```yml
settings:
  logins:
    - registry: https://codeberg.org
      username: "6543"
      password: geheim
    - registry: https://index.docker.io/v1/
      username: a6543
      password: anders_geheim
```

close #18

Reviewed-on: https://codeberg.org/woodpecker-plugins/plugin-docker-buildx/pulls/23
Reviewed-by: anbraten <anbraten@noreply.codeberg.org>

cmd/docker-buildx/config.go

@@ -200,31 +200,38 @@ func settingsFlags(settings *plugin.Settings) []cli.Flag {
 			EnvVars:     []string{"PLUGIN_REGISTRY", "DOCKER_REGISTRY"},
 			Usage:       "sets docker registry to authenticate with",
 			Value:       "https://index.docker.io/v1/",
-			Destination: &settings.Login.Registry,
+			Destination: &settings.DefaultLogin.Registry,
 		},
 		&cli.StringFlag{
 			Name:        "docker.username",
 			EnvVars:     []string{"PLUGIN_USERNAME", "DOCKER_USERNAME"},
 			Usage:       "sets username to authenticates with",
-			Destination: &settings.Login.Username,
+			Destination: &settings.DefaultLogin.Username,
 		},
 		&cli.StringFlag{
 			Name:        "docker.password",
 			EnvVars:     []string{"PLUGIN_PASSWORD", "DOCKER_PASSWORD"},
 			Usage:       "sets password to authenticates with",
-			Destination: &settings.Login.Password,
+			Destination: &settings.DefaultLogin.Password,
 		},
 		&cli.StringFlag{
 			Name:        "docker.email",
 			EnvVars:     []string{"PLUGIN_EMAIL", "DOCKER_EMAIL"},
 			Usage:       "sets email address to authenticates with",
-			Destination: &settings.Login.Email,
+			Destination: &settings.DefaultLogin.Email,
 		},
 		&cli.StringFlag{
 			Name:        "docker.config",
 			EnvVars:     []string{"PLUGIN_CONFIG", "DOCKER_PLUGIN_CONFIG"},
 			Usage:       "sets content of the docker daemon json config",
-			Destination: &settings.Login.Config,
+			Destination: &settings.DefaultLogin.Config,
+		},
+		&cli.StringFlag{
+			Name:        "logins",
+			EnvVars:     []string{"PLUGIN_LOGINS"},
+			Usage:       "list of login",
+			Destination: &settings.LoginsRaw,
+			Value:       "[]",
 		},
 		&cli.BoolFlag{
 			Name:        "docker.purge",

cmd/docker-buildx/tools.go

@@ -1,3 +1,4 @@
+//go:build tools
 // +build tools
 
 package tools