Merge pull request #817 from tonistiigi/project-sharedkey

build: set local sharedkey per project basename

util/confutil/config.go

@@ -2,11 +2,28 @@ package confutil
 
 import (
 	"os"
+	"path/filepath"
 
+	"github.com/docker/cli/cli/command"
 	"github.com/pelletier/go-toml"
 	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
 )
 
+// ConfigDir will look for correct configuration store path;
+// if `$BUILDX_CONFIG` is set - use it, otherwise use parent directory
+// of Docker config file (i.e. `${DOCKER_CONFIG}/buildx`)
+func ConfigDir(dockerCli command.Cli) string {
+	if buildxConfig := os.Getenv("BUILDX_CONFIG"); buildxConfig != "" {
+		logrus.Debugf("using config store %q based in \"$BUILDX_CONFIG\" environment variable", buildxConfig)
+		return buildxConfig
+	}
+
+	buildxConfig := filepath.Join(filepath.Dir(dockerCli.ConfigFile().Filename), "buildx")
+	logrus.Debugf("using default config store %q", buildxConfig)
+	return buildxConfig
+}
+
 // loadConfigTree loads BuildKit config toml tree
 func loadConfigTree(fp string) (*toml.Tree, error) {
 	f, err := os.Open(fp)