refactor proxy

Signed-off-by: Christian Richter <crichter@owncloud.com>

extensions/proxy/pkg/config/parser/parse.go

@@ -0,0 +1,32 @@
+package parser
+
+import (
+	"errors"
+
+	"github.com/owncloud/ocis/extensions/proxy/pkg/config"
+	"github.com/owncloud/ocis/extensions/proxy/pkg/config/defaults"
+	ociscfg "github.com/owncloud/ocis/ocis-pkg/config"
+
+	"github.com/owncloud/ocis/ocis-pkg/config/envdecode"
+)
+
+// ParseConfig loads accounts configuration from known paths.
+func ParseConfig(cfg *config.Config) error {
+	_, err := ociscfg.BindSourcesToStructs(cfg.Service.Name, cfg)
+	if err != nil {
+		return err
+	}
+
+	defaults.EnsureDefaults(cfg)
+	// load all env variables relevant to the config in the current context.
+	if err := envdecode.Decode(cfg); err != nil {
+		// no environment variable set for this config is an expected "error"
+		if !errors.Is(err, envdecode.ErrNoTargetFieldsAreSet) {
+			return err
+		}
+	}
+
+	defaults.Sanitize(cfg)
+
+	return nil
+}