From 904641bf10036ee91bbe3d67e290721673158f6c Mon Sep 17 00:00:00 2001
From: Albie <albion@dragonfruit.network>
Date: Thu, 8 Jul 2021 08:00:51 +0100
Subject: [PATCH] feat: add option to specify buildkit config file path (#32)

---
 cmd/drone-docker-buildx/config.go |  6 ++++++
 plugin/docker.go                  | 14 +++++++++++--
 plugin/impl.go                    | 35 ++++++++++++++++++-------------
 3 files changed, 39 insertions(+), 16 deletions(-)

diff --git a/cmd/drone-docker-buildx/config.go b/cmd/drone-docker-buildx/config.go
index 82aecec..a561ae7 100644
--- a/cmd/drone-docker-buildx/config.go
+++ b/cmd/drone-docker-buildx/config.go
@@ -93,6 +93,12 @@ func settingsFlags(settings *plugin.Settings) []cli.Flag {
 			EnvVars:     []string{"PLUGIN_DAEMON_OFF"},
 			Destination: &settings.Daemon.Disabled,
 		},
+		&cli.StringFlag{
+			Name:        "daemon.buildkit-config",
+			Usage:       "location of buildkit config file",
+			EnvVars:     []string{"PLUGIN_BUILDKIT_CONFIG"},
+			Destination: &settings.Daemon.BuildkitConfig,
+		},
 		&cli.StringFlag{
 			Name:        "dockerfile",
 			Usage:       "build dockerfile",
diff --git a/plugin/docker.go b/plugin/docker.go
index d73e9b0..1a99fe0 100644
--- a/plugin/docker.go
+++ b/plugin/docker.go
@@ -52,8 +52,18 @@ func commandInfo() *exec.Cmd {
 	return exec.Command(dockerExe, "info")
 }
 
-func commandBuilder() *exec.Cmd {
-	return exec.Command(dockerExe, "buildx", "create", "--use")
+func commandBuilder(daemon Daemon) *exec.Cmd {
+	args := []string{
+		"buildx", 
+		"create", 
+		"--use",
+	}
+
+	if daemon.BuildkitConfig != "" {
+		args = append(args, "--config", daemon.BuildkitConfig)
+	}
+
+	return exec.Command(dockerExe, args...)
 }
 
 func commandBuildx() *exec.Cmd {
diff --git a/plugin/impl.go b/plugin/impl.go
index 0cd15eb..a4c8378 100644
--- a/plugin/impl.go
+++ b/plugin/impl.go
@@ -14,19 +14,20 @@ import (
 
 // Daemon defines Docker daemon parameters.
 type Daemon struct {
-	Registry      string          // Docker registry
-	Mirror        string          // Docker registry mirror
-	Insecure      bool            // Docker daemon enable insecure registries
-	StorageDriver string          // Docker daemon storage driver
-	StoragePath   string          // Docker daemon storage path
-	Disabled      bool            // DOcker daemon is disabled (already running)
-	Debug         bool            // Docker daemon started in debug mode
-	Bip           string          // Docker daemon network bridge IP address
-	DNS           cli.StringSlice // Docker daemon dns server
-	DNSSearch     cli.StringSlice // Docker daemon dns search domain
-	MTU           string          // Docker daemon mtu setting
-	IPv6          bool            // Docker daemon IPv6 networking
-	Experimental  bool            // Docker daemon enable experimental mode
+	Registry       string          // Docker registry
+	Mirror         string          // Docker registry mirror
+	Insecure       bool            // Docker daemon enable insecure registries
+	StorageDriver  string          // Docker daemon storage driver
+	StoragePath    string          // Docker daemon storage path
+	Disabled       bool            // DOcker daemon is disabled (already running)
+	Debug          bool            // Docker daemon started in debug mode
+	Bip            string          // Docker daemon network bridge IP address
+	DNS            cli.StringSlice // Docker daemon dns server
+	DNSSearch      cli.StringSlice // Docker daemon dns search domain
+	MTU            string          // Docker daemon mtu setting
+	IPv6           bool            // Docker daemon IPv6 networking
+	Experimental   bool            // Docker daemon enable experimental mode
+	BuildkitConfig string          // Docker buildkit config file
 }
 
 // Login defines Docker login parameters.
@@ -77,6 +78,12 @@ func (p *Plugin) Validate() error {
 	p.settings.Build.Ref = p.pipeline.Commit.Ref
 	p.settings.Daemon.Registry = p.settings.Login.Registry
 
+	if p.settings.Daemon.BuildkitConfig != "" {
+		if _, err := os.Stat(p.settings.Daemon.BuildkitConfig); err != nil && os.IsNotExist(err) {
+			return fmt.Errorf("given buildkit config file not found")
+		}
+	}
+
 	if p.settings.Build.TagsAuto {
 		// return true if tag event or default branch
 		if UseDefaultTag(
@@ -159,7 +166,7 @@ func (p *Plugin) Execute() error {
 	var cmds []*exec.Cmd
 	cmds = append(cmds, commandVersion()) // docker version
 	cmds = append(cmds, commandInfo())    // docker info
-	cmds = append(cmds, commandBuilder())
+	cmds = append(cmds, commandBuilder(p.settings.Daemon))
 	cmds = append(cmds, commandBuildx())
 
 	// pre-pull cache images