refactor env unbinding to ocis-pkg

ocis-pkg/config/config.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"reflect"
 
+	"github.com/owncloud/ocis/ocis-pkg/shared"
+
 	gofig "github.com/gookit/config/v2"
 	accounts "github.com/owncloud/ocis/accounts/pkg/config"
 	glauth "github.com/owncloud/ocis/glauth/pkg/config"
@@ -130,11 +132,6 @@ func New() *Config {
 	}
 }
 
-type mapping struct {
-	EnvVars     []string    // name of the EnvVars var.
-	Destination interface{} // memory address of the original config value to modify.
-}
-
 // GetEnv fetches a list of known env variables for this extension. It is to be used by gookit, as it provides a list
 // with all the environment variables an extension supports.
 func GetEnv() []string {
@@ -182,8 +179,8 @@ func (c *Config) UnmapEnv(gooconf *gofig.Config) error {
 }
 
 // structMappings binds a set of environment variables to a destination on cfg.
-func structMappings(cfg *Config) []mapping {
-	return []mapping{
+func structMappings(cfg *Config) []shared.EnvBinding {
+	return []shared.EnvBinding{
 		{
 			EnvVars:     []string{"OCIS_LOG_FILE"},
 			Destination: &cfg.Log.Level,

ocis-pkg/config/environment.go

@@ -0,0 +1,48 @@
+package config
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/owncloud/ocis/ocis-pkg/shared"
+
+	gofig "github.com/gookit/config/v2"
+)
+
+// UnbindEnv takes a config `c` and a EnvBinding
+func UnbindEnv(c *gofig.Config, bindings []shared.EnvBinding) error {
+	return unbindEnv(c, bindings)
+}
+
+func unbindEnv(c *gofig.Config, bindings []shared.EnvBinding) error {
+	for i := range bindings {
+		for j := range bindings[i].EnvVars {
+			// we need to guard against v != "" because this is the condition that checks that the value is set from the environment.
+			// the `ok` guard is not enough, apparently.
+			if v, ok := c.GetValue(bindings[i].EnvVars[j]); ok && v != "" {
+
+				// get the destination type from destination
+				switch reflect.ValueOf(bindings[i].Destination).Type().String() {
+				case "*bool":
+					r := c.Bool(bindings[i].EnvVars[j])
+					*bindings[i].Destination.(*bool) = r
+				case "*string":
+					r := c.String(bindings[i].EnvVars[j])
+					*bindings[i].Destination.(*string) = r
+				case "*int":
+					r := c.Int(bindings[i].EnvVars[j])
+					*bindings[i].Destination.(*int) = r
+				case "*float64":
+					// defaults to float64
+					r := c.Float(bindings[i].EnvVars[j])
+					*bindings[i].Destination.(*float64) = r
+				default:
+					// it is unlikely we will ever get here. Let this serve more as a runtime check for when debugging.
+					return fmt.Errorf("invalid type for env var: `%v`", bindings[i].EnvVars[j])
+				}
+			}
+		}
+	}
+
+	return nil
+}

ocis-pkg/shared/shared_types.go

@@ -0,0 +1,9 @@
+package shared
+
+// EnvBinding represents a direct binding from an env variable to a go kind. Along with gookit/config, its primal goal
+// is to unpack environment variables into a Go value. We do so with reflection, and this data structure is just a step
+// in between.
+type EnvBinding struct {
+	EnvVars     []string    // name of the environment var.
+	Destination interface{} // pointer to the original config value to modify.
+}

proxy/pkg/command/root.go

@@ -72,12 +72,8 @@ func ParseConfig(c *cli.Context, cfg *config.Config) error {
 
 	// load all env variables relevant to the config in the current context.
 	conf.LoadOSEnv(config.GetEnv(), false)
-
-	if err = cfg.UnmapEnv(conf); err != nil {
-		return err
-	}
-
-	return nil
+	bindings := config.StructMappings(cfg)
+	return ociscfg.UnbindEnv(conf, bindings)
 }
 
 // SutureService allows for the proxy command to be embedded and supervised by a suture supervisor tree.

proxy/pkg/config/env.go

@@ -1,12 +1,5 @@
 package config
 
-import (
-	"fmt"
-	"reflect"
-
-	gofig "github.com/gookit/config/v2"
-)
-
 type mapping struct {
 	EnvVars     []string    // name of the EnvVars var.
 	Destination interface{} // memory address of the original config value to modify.
@@ -22,38 +15,3 @@ func GetEnv() []string {
 
 	return r
 }
-
-// UnmapEnv loads values from the gooconf.Config argument and sets them in the expected destination.
-func (c *Config) UnmapEnv(gooconf *gofig.Config) error {
-	vals := structMappings(c)
-	for i := range vals {
-		for j := range vals[i].EnvVars {
-			// we need to guard against v != "" because this is the condition that checks that the value is set from the environment.
-			// the `ok` guard is not enough, apparently.
-			if v, ok := gooconf.GetValue(vals[i].EnvVars[j]); ok && v != "" {
-
-				// get the destination type from destination
-				switch reflect.ValueOf(vals[i].Destination).Type().String() {
-				case "*bool":
-					r := gooconf.Bool(vals[i].EnvVars[j])
-					*vals[i].Destination.(*bool) = r
-				case "*string":
-					r := gooconf.String(vals[i].EnvVars[j])
-					*vals[i].Destination.(*string) = r
-				case "*int":
-					r := gooconf.Int(vals[i].EnvVars[j])
-					*vals[i].Destination.(*int) = r
-				case "*float64":
-					// defaults to float64
-					r := gooconf.Float(vals[i].EnvVars[j])
-					*vals[i].Destination.(*float64) = r
-				default:
-					// it is unlikely we will ever get here. Let this serve more as a runtime check for when debugging.
-					return fmt.Errorf("invalid type for env var: `%v`", vals[i].EnvVars[j])
-				}
-			}
-		}
-	}
-
-	return nil
-}

proxy/pkg/config/mappings.go

@@ -1,8 +1,14 @@
 package config
 
-// structMappings binds a set of environment variables to a destination on cfg.
-func structMappings(cfg *Config) []mapping {
-	return []mapping{
+import "github.com/owncloud/ocis/ocis-pkg/shared"
+
+// StructMappings binds a set of environment variables to a destination on cfg.
+func StructMappings(cfg *Config) []shared.EnvBinding {
+	return structMappings(cfg)
+}
+
+func structMappings(cfg *Config) []shared.EnvBinding {
+	return []shared.EnvBinding{
 		// Logging
 		{
 			EnvVars:     []string{"PROXY_LOG_LEVEL", "OCIS_LOG_LEVEL"},