Merge pull request #33 from antonmashko/24-custom-unmarshalling

#24 encoding.TextUnmarshaller & encoding.BinaryUnmarshaller support

config_sources.go

@@ -1,7 +1,6 @@
 package envconf
 
 import (
-	"errors"
 	"flag"
 	"os"
 	"reflect"
@@ -22,14 +21,6 @@ const (
 	valDefault    = "*"
 )
 
-var (
-	//errors
-	errInvalidFiled              = errors.New("invalid field")
-	errFiledIsNotSettable        = errors.New("field is not settable")
-	ErrUnsupportedType           = errors.New("unsupported type")
-	errConfigurationNotSpecified = errors.New("configuration not specified")
-)
-
 type flagSource struct {
 	name    string
 	v       string
@@ -116,14 +107,6 @@ func newExternalValueSource(f field, ext *externalConfig) *externalValueSource {
 	}
 }
 
-func (s *externalValueSource) Name() string {
-	name, ok := s.f.structField().Tag.Lookup(tagEnv)
-	if !ok {
-		name = s.f.name()
-	}
-	return name
-}
-
 func (s *externalValueSource) Value() (interface{}, bool) {
 	return s.ext.get(s.f)
 }
@@ -139,10 +122,6 @@ func newDefaultValueSource(tag reflect.StructField) *defaultValueSource {
 	return &s
 }
 
-func (s *defaultValueSource) Name() string {
-	return tagDefault
-}
-
 func (s *defaultValueSource) Value() (interface{}, bool) {
 	return s.v, s.defined
 }

error.go

@@ -1,6 +1,16 @@
 package envconf
 
-import "fmt"
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	// ErrNilData mean that exists nil pointer inside data struct
+	ErrNilData               = errors.New("nil data")
+	ErrUnsupportedType       = errors.New("unsupported type")
+	ErrConfigurationNotFound = errors.New("configuration not found")
+)
 
 type Error struct {
 	Inner     error

external/external_test.go

@@ -1,15 +1,67 @@
 package external
 
 import (
+	"errors"
+	"io"
+	"os"
 	"testing"
 
 	"github.com/antonmashko/envconf/option"
 )
 
 func TestWithFlagConfigFile_Ok(t *testing.T) {
-	opt := WithFlagConfigFile("config", "", "", func(b []byte) error {
+	f, err := os.CreateTemp("", "envconf.tmp")
+	if err != nil {
+		t.Fatal("os.Create:", err)
+	}
+	defer f.Close()
+	defer os.Remove(f.Name())
+	const content = `{"foo":"bar"}`
+	_, err = io.WriteString(f, content)
+	if err != nil {
+		t.Fatal("io.WriteString: ", err)
+	}
+	var result string
+	opt := WithFlagConfigFile("config1", f.Name(), "", func(b []byte) error {
+		result = string(b)
 		return nil
 	})
 	opts := &option.Options{}
 	opt.Apply(opts)
+	if err = opts.FlagParsed()(); err != nil {
+		t.Fatal("opts.FlagParsed(): ", err)
+	}
+	if result != content {
+		t.Fatal("unexpected result: ", result)
+	}
+}
+
+func TestWithFlagConfigFile_NotExist_Err(t *testing.T) {
+	opt := WithFlagConfigFile("config2", "./conf.json", "", func(b []byte) error {
+		return nil
+	})
+	opts := &option.Options{}
+	opt.Apply(opts)
+	if err := opts.FlagParsed()(); err == nil {
+		t.Fatal("expected error but got nil")
+	}
+}
+
+func TestWithFlagConfigFile_CustomError_Err(t *testing.T) {
+	f, err := os.CreateTemp("", "envconf.tmp")
+	if err != nil {
+		t.Fatal("os.Create:", err)
+	}
+	defer f.Close()
+	defer os.Remove(f.Name())
+
+	cErr := errors.New("custom error")
+	opt := WithFlagConfigFile("config3", f.Name(), "", func(b []byte) error {
+		return cErr
+	})
+	opts := &option.Options{}
+	opt.Apply(opts)
+	if err = opts.FlagParsed()(); err == nil || err != cErr {
+		t.Fatal("opts.FlagParsed() unexpected error: ", err)
+	}
 }

field.go

@@ -1,9 +1,8 @@
 package envconf
 
 import (
-	"net/url"
+	"encoding"
 	"reflect"
-	"time"
 )
 
 const fieldNameDelim = "."
@@ -48,14 +47,18 @@ func (emptyField) structField() reflect.StructField {
 }
 
 func createFieldFromValue(v reflect.Value, p *structType, t reflect.StructField) field {
+	// validate reflect value
+	if !v.CanInterface() {
+		return emptyField{}
+	}
 	switch v.Kind() {
 	case reflect.Struct:
-		switch v.Interface().(type) {
-		case url.URL, time.Time:
-			return newPrimitiveType(v, p, t)
-		default:
-			return newStructType(v, p, t)
+		// implementations check
+		implF := asImpl(v)
+		if implF != nil {
+			return newFieldType(v, p, t)
 		}
+		return newStructType(v, p, t)
 	case reflect.Ptr:
 		return newPtrType(v, p, t)
 	case reflect.Interface:
@@ -64,7 +67,7 @@ func createFieldFromValue(v reflect.Value, p *structType, t reflect.StructField)
 		// unsupported types
 		return emptyField{}
 	default:
-		return newPrimitiveType(v, p, t)
+		return newFieldType(v, p, t)
 	}
 }
 
@@ -82,3 +85,35 @@ func fullname(f field) string {
 	}
 	return name
 }
+
+func asImpl(field reflect.Value) func([]byte) error {
+	f := func(v interface{}) func([]byte) error {
+		// encoding.TextUnmarshaler
+		tu, ok := v.(encoding.TextUnmarshaler)
+		if ok {
+			return tu.UnmarshalText
+		}
+		// encoding.BinaryUnmarshaller
+		bu, ok := v.(encoding.BinaryUnmarshaler)
+		if ok {
+			return bu.UnmarshalBinary
+		}
+		// ----
+		return nil
+	}
+	// NOTE: max double pointer support
+	for i := 0; i < 3; i++ {
+		resF := f(field.Interface())
+		if resF != nil {
+			return resF
+		}
+		if !field.CanAddr() {
+			return nil
+		}
+		field = field.Addr()
+		if !field.CanInterface() {
+			return nil
+		}
+	}
+	return nil
+}

field_test.go

@@ -0,0 +1,27 @@
+package envconf
+
+import (
+	"testing"
+)
+
+func TestEmptyField_Ok(t *testing.T) {
+	et := emptyField{}
+	if err := et.init(); err != nil {
+		t.Fatal("emptyField.init: ", err)
+	}
+	if err := et.define(); err != nil {
+		t.Fatal("emptyField.define: ", err)
+	}
+	if et.isSet() {
+		t.Fatal("emptyField.isSet: true")
+	}
+	if et.name() != "" {
+		t.Fatal("emptyField.name: ", et.name())
+	}
+	if et.parent() != nil {
+		t.Fatal("emptyField.parent: ", et.parent())
+	}
+	if et.structField().Tag != "" {
+		t.Fatal("emptyField.structField: ", et.structField().Tag)
+	}
+}

parser.go

@@ -1,15 +1,11 @@
 package envconf
 
 import (
-	"errors"
 	"flag"
 
 	"github.com/antonmashko/envconf/option"
 )
 
-// ErrNilData mean that exists nil pointer inside data struct
-var ErrNilData = errors.New("nil data")
-
 type EnvConf struct {
 	external *externalConfig
 	opts     *option.Options
@@ -27,7 +23,7 @@ func NewWithExternal(e External) *EnvConf {
 }
 
 func (e *EnvConf) fieldInitialized(f field) {
-	pt, ok := f.(*primitiveType)
+	pt, ok := f.(*fieldType)
 	if !ok {
 		return
 	}
@@ -45,7 +41,7 @@ func (e *EnvConf) fieldInitialized(f field) {
 }
 
 func (e *EnvConf) fieldDefined(f field) {
-	pt, ok := f.(*primitiveType)
+	pt, ok := f.(*fieldType)
 	if !ok {
 		return
 	}
@@ -68,7 +64,7 @@ func (e *EnvConf) fieldDefined(f field) {
 }
 
 func (e *EnvConf) fieldNotDefined(f field, err error) {
-	pt, ok := f.(*primitiveType)
+	pt, ok := f.(*fieldType)
 	if !ok {
 		return
 	}

parser_primitives_test.go → parser_field_test.go

@@ -373,3 +373,13 @@ func TestParse_ValueWithSpace_Ok(t *testing.T) {
 		t.Errorf("incorrect result:%#v", cfg)
 	}
 }
+
+func TestParse_PrivateField_Ok(t *testing.T) {
+	cfg := struct {
+		field2 string `default:"f2"`
+	}{}
+
+	if err := envconf.Parse(&cfg); err != nil {
+		t.Fatal(err)
+	}
+}