feat: load buildkit config from string instead of file (#37)

cmd/drone-docker-buildx/config.go

@@ -95,7 +95,7 @@ func settingsFlags(settings *plugin.Settings) []cli.Flag {
 		},
 		&cli.StringFlag{
 			Name:        "daemon.buildkit-config",
-			Usage:       "location of buildkit config file",
+			Usage:       "docker buildkit json config content",
 			EnvVars:     []string{"PLUGIN_BUILDKIT_CONFIG"},
 			Destination: &settings.Daemon.BuildkitConfig,
 		},

go.sum

@@ -12,7 +12,6 @@ github.com/drone-plugins/drone-plugin-lib v0.4.0/go.mod h1:EgqogX38GoJFtckeSQyhB
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/joho/godotenv v1.3.0 h1:Zjp+RcGpHhGlrMbJzXTrZZPrWj+1vfm90La1wgB6Bhc=
 github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
-github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -71,7 +70,5 @@ gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.3 h1:fvjTMHxHEw/mxHbtzPi3JCcKXQRAnQTBRo6YCJSVHKI=
 gopkg.in/yaml.v2 v2.2.3/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gotest.tools/v3 v3.0.2/go.mod h1:3SzNCllyD9/Y+b5r9JIKQ474KzkZyqLqEfYqMsX94Bk=
-honnef.co/go/tools v0.1.4 h1:SadWOkti5uVN1FAMgxn165+Mw00fuQKyk4Gyn/inxNQ=
-honnef.co/go/tools v0.1.4/go.mod h1:NgwopIslSNH47DimFoV78dnkksY2EFtX0ajyb3K/las=
 honnef.co/go/tools v0.2.0 h1:ws8AfbgTX3oIczLPNPCu5166oBg9ST2vNs0rcht+mDE=
 honnef.co/go/tools v0.2.0/go.mod h1:lPVVZ2BS5TfnjLyizF7o7hv7j9/L+8cZY2hLyjP9cGY=

plugin/daemon.go

@@ -1,13 +1,14 @@
 package plugin
 
 import (
-	"io/ioutil"
+	"io"
 	"os"
 )
 
 const dockerExe = "/usr/local/bin/docker"
 const dockerdExe = "/usr/local/bin/dockerd"
 const dockerHome = "/root/.docker/"
+const buildkitConfig = "/tmp/buildkit.json"
 
 func (p Plugin) startDaemon() {
 	cmd := commandDaemon(p.settings.Daemon)
@@ -15,8 +16,8 @@ func (p Plugin) startDaemon() {
 		cmd.Stdout = os.Stdout
 		cmd.Stderr = os.Stderr
 	} else {
-		cmd.Stdout = ioutil.Discard
+		cmd.Stdout = io.Discard
-		cmd.Stderr = ioutil.Discard
+		cmd.Stderr = io.Discard
 	}
 	go func() {
 		trace(cmd)

plugin/docker.go

@@ -54,13 +54,13 @@ func commandInfo() *exec.Cmd {
 
 func commandBuilder(daemon Daemon) *exec.Cmd {
 	args := []string{
-		"buildx", 
+		"buildx",
-		"create", 
+		"create",
 		"--use",
 	}
 
 	if daemon.BuildkitConfig != "" {
-		args = append(args, "--config", daemon.BuildkitConfig)
+		args = append(args, "--config", buildkitConfig)
 	}
 
 	return exec.Command(dockerExe, args...)
@@ -84,7 +84,7 @@ func commandBuild(build Build, dryrun bool) *exec.Cmd {
 	}
 
 	args = append(args, build.Context)
-	if ! dryrun {
+	if !dryrun {
 		args = append(args, "--push")
 	}
 	if build.Squash {
@@ -124,7 +124,7 @@ func commandBuild(build Build, dryrun bool) *exec.Cmd {
 
 	for _, arg := range build.Tags.Value() {
 		args = append(args, "-t", fmt.Sprintf("%s:%s", build.Repo, arg))
-	}	
+	}
 
 	return exec.Command(dockerExe, args...)
 }

plugin/impl.go

@@ -2,7 +2,6 @@ package plugin
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -27,7 +26,7 @@ type Daemon struct {
 	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
+	BuildkitConfig string          // Docker buildkit config
 }
 
 // Login defines Docker login parameters.
@@ -78,12 +77,6 @@ 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(
@@ -131,7 +124,7 @@ func (p *Plugin) Execute() error {
 		os.MkdirAll(dockerHome, 0600)
 
 		path := filepath.Join(dockerHome, "config.json")
-		err := ioutil.WriteFile(path, []byte(p.settings.Login.Config), 0600)
+		err := os.WriteFile(path, []byte(p.settings.Login.Config), 0600)
 		if err != nil {
 			return fmt.Errorf("error writing config.json: %s", err)
 		}
@@ -146,6 +139,13 @@ func (p *Plugin) Execute() error {
 		}
 	}
 
+	if p.settings.Daemon.BuildkitConfig != "" {
+		err := os.WriteFile(buildkitConfig, []byte(p.settings.Daemon.BuildkitConfig), 0600)
+		if err != nil {
+			return fmt.Errorf("error writing buildkit.json: %s", err)
+		}
+	}
+
 	switch {
 	case p.settings.Login.Password != "":
 		fmt.Println("Detected registry credentials")