Merge pull request #4832 from baude/apiv2tomaster

Apiv2tomaster

1 files changed, 504 insertions, 0 deletions

diff --git a/vendor/github.com/gorilla/schema/decoder.go b/vendor/github.com/gorilla/schema/decoder.go
new file mode 100644
index 000000000..5afbd921f
--- /dev/null
+++ b/vendor/github.com/gorilla/schema/decoder.go
@@ -0,0 +1,504 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package schema
+
+import (
+	"encoding"
+	"errors"
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// NewDecoder returns a new Decoder.
+func NewDecoder() *Decoder {
+	return &Decoder{cache: newCache()}
+}
+
+// Decoder decodes values from a map[string][]string to a struct.
+type Decoder struct {
+	cache             *cache
+	zeroEmpty         bool
+	ignoreUnknownKeys bool
+}
+
+// SetAliasTag changes the tag used to locate custom field aliases.
+// The default tag is "schema".
+func (d *Decoder) SetAliasTag(tag string) {
+	d.cache.tag = tag
+}
+
+// ZeroEmpty controls the behaviour when the decoder encounters empty values
+// in a map.
+// If z is true and a key in the map has the empty string as a value
+// then the corresponding struct field is set to the zero value.
+// If z is false then empty strings are ignored.
+//
+// The default value is false, that is empty values do not change
+// the value of the struct field.
+func (d *Decoder) ZeroEmpty(z bool) {
+	d.zeroEmpty = z
+}
+
+// IgnoreUnknownKeys controls the behaviour when the decoder encounters unknown
+// keys in the map.
+// If i is true and an unknown field is encountered, it is ignored. This is
+// similar to how unknown keys are handled by encoding/json.
+// If i is false then Decode will return an error. Note that any valid keys
+// will still be decoded in to the target struct.
+//
+// To preserve backwards compatibility, the default value is false.
+func (d *Decoder) IgnoreUnknownKeys(i bool) {
+	d.ignoreUnknownKeys = i
+}
+
+// RegisterConverter registers a converter function for a custom type.
+func (d *Decoder) RegisterConverter(value interface{}, converterFunc Converter) {
+	d.cache.registerConverter(value, converterFunc)
+}
+
+// Decode decodes a map[string][]string to a struct.
+//
+// The first parameter must be a pointer to a struct.
+//
+// The second parameter is a map, typically url.Values from an HTTP request.
+// Keys are "paths" in dotted notation to the struct fields and nested structs.
+//
+// See the package documentation for a full explanation of the mechanics.
+func (d *Decoder) Decode(dst interface{}, src map[string][]string) error {
+	v := reflect.ValueOf(dst)
+	if v.Kind() != reflect.Ptr || v.Elem().Kind() != reflect.Struct {
+		return errors.New("schema: interface must be a pointer to struct")
+	}
+	v = v.Elem()
+	t := v.Type()
+	errors := MultiError{}
+	for path, values := range src {
+		if parts, err := d.cache.parsePath(path, t); err == nil {
+			if err = d.decode(v, path, parts, values); err != nil {
+				errors[path] = err
+			}
+		} else if !d.ignoreUnknownKeys {
+			errors[path] = UnknownKeyError{Key: path}
+		}
+	}
+	errors.merge(d.checkRequired(t, src))
+	if len(errors) > 0 {
+		return errors
+	}
+	return nil
+}
+
+// checkRequired checks whether required fields are empty
+//
+// check type t recursively if t has struct fields.
+//
+// src is the source map for decoding, we use it here to see if those required fields are included in src
+func (d *Decoder) checkRequired(t reflect.Type, src map[string][]string) MultiError {
+	m, errs := d.findRequiredFields(t, "", "")
+	for key, fields := range m {
+		if isEmptyFields(fields, src) {
+			errs[key] = EmptyFieldError{Key: key}
+		}
+	}
+	return errs
+}
+
+// findRequiredFields recursively searches the struct type t for required fields.
+//
+// canonicalPrefix and searchPrefix are used to resolve full paths in dotted notation
+// for nested struct fields. canonicalPrefix is a complete path which never omits
+// any embedded struct fields. searchPrefix is a user-friendly path which may omit
+// some embedded struct fields to point promoted fields.
+func (d *Decoder) findRequiredFields(t reflect.Type, canonicalPrefix, searchPrefix string) (map[string][]fieldWithPrefix, MultiError) {
+	struc := d.cache.get(t)
+	if struc == nil {
+		// unexpect, cache.get never return nil
+		return nil, MultiError{canonicalPrefix + "*": errors.New("cache fail")}
+	}
+
+	m := map[string][]fieldWithPrefix{}
+	errs := MultiError{}
+	for _, f := range struc.fields {
+		if f.typ.Kind() == reflect.Struct {
+			fcprefix := canonicalPrefix + f.canonicalAlias + "."
+			for _, fspath := range f.paths(searchPrefix) {
+				fm, ferrs := d.findRequiredFields(f.typ, fcprefix, fspath+".")
+				for key, fields := range fm {
+					m[key] = append(m[key], fields...)
+				}
+				errs.merge(ferrs)
+			}
+		}
+		if f.isRequired {
+			key := canonicalPrefix + f.canonicalAlias
+			m[key] = append(m[key], fieldWithPrefix{
+				fieldInfo: f,
+				prefix:    searchPrefix,
+			})
+		}
+	}
+	return m, errs
+}
+
+type fieldWithPrefix struct {
+	*fieldInfo
+	prefix string
+}
+
+// isEmptyFields returns true if all of specified fields are empty.
+func isEmptyFields(fields []fieldWithPrefix, src map[string][]string) bool {
+	for _, f := range fields {
+		for _, path := range f.paths(f.prefix) {
+			if !isEmpty(f.typ, src[path]) {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// isEmpty returns true if value is empty for specific type
+func isEmpty(t reflect.Type, value []string) bool {
+	if len(value) == 0 {
+		return true
+	}
+	switch t.Kind() {
+	case boolType, float32Type, float64Type, intType, int8Type, int32Type, int64Type, stringType, uint8Type, uint16Type, uint32Type, uint64Type:
+		return len(value[0]) == 0
+	}
+	return false
+}
+
+// decode fills a struct field using a parsed path.
+func (d *Decoder) decode(v reflect.Value, path string, parts []pathPart, values []string) error {
+	// Get the field walking the struct fields by index.
+	for _, name := range parts[0].path {
+		if v.Type().Kind() == reflect.Ptr {
+			if v.IsNil() {
+				v.Set(reflect.New(v.Type().Elem()))
+			}
+			v = v.Elem()
+		}
+		v = v.FieldByName(name)
+	}
+	// Don't even bother for unexported fields.
+	if !v.CanSet() {
+		return nil
+	}
+
+	// Dereference if needed.
+	t := v.Type()
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+		if v.IsNil() {
+			v.Set(reflect.New(t))
+		}
+		v = v.Elem()
+	}
+
+	// Slice of structs. Let's go recursive.
+	if len(parts) > 1 {
+		idx := parts[0].index
+		if v.IsNil() || v.Len() < idx+1 {
+			value := reflect.MakeSlice(t, idx+1, idx+1)
+			if v.Len() < idx+1 {
+				// Resize it.
+				reflect.Copy(value, v)
+			}
+			v.Set(value)
+		}
+		return d.decode(v.Index(idx), path, parts[1:], values)
+	}
+
+	// Get the converter early in case there is one for a slice type.
+	conv := d.cache.converter(t)
+	m := isTextUnmarshaler(v)
+	if conv == nil && t.Kind() == reflect.Slice && m.IsSliceElement {
+		var items []reflect.Value
+		elemT := t.Elem()
+		isPtrElem := elemT.Kind() == reflect.Ptr
+		if isPtrElem {
+			elemT = elemT.Elem()
+		}
+
+		// Try to get a converter for the element type.
+		conv := d.cache.converter(elemT)
+		if conv == nil {
+			conv = builtinConverters[elemT.Kind()]
+			if conv == nil {
+				// As we are not dealing with slice of structs here, we don't need to check if the type
+				// implements TextUnmarshaler interface
+				return fmt.Errorf("schema: converter not found for %v", elemT)
+			}
+		}
+
+		for key, value := range values {
+			if value == "" {
+				if d.zeroEmpty {
+					items = append(items, reflect.Zero(elemT))
+				}
+			} else if m.IsValid {
+				u := reflect.New(elemT)
+				if m.IsSliceElementPtr {
+					u = reflect.New(reflect.PtrTo(elemT).Elem())
+				}
+				if err := u.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(value)); err != nil {
+					return ConversionError{
+						Key:   path,
+						Type:  t,
+						Index: key,
+						Err:   err,
+					}
+				}
+				if m.IsSliceElementPtr {
+					items = append(items, u.Elem().Addr())
+				} else if u.Kind() == reflect.Ptr {
+					items = append(items, u.Elem())
+				} else {
+					items = append(items, u)
+				}
+			} else if item := conv(value); item.IsValid() {
+				if isPtrElem {
+					ptr := reflect.New(elemT)
+					ptr.Elem().Set(item)
+					item = ptr
+				}
+				if item.Type() != elemT && !isPtrElem {
+					item = item.Convert(elemT)
+				}
+				items = append(items, item)
+			} else {
+				if strings.Contains(value, ",") {
+					values := strings.Split(value, ",")
+					for _, value := range values {
+						if value == "" {
+							if d.zeroEmpty {
+								items = append(items, reflect.Zero(elemT))
+							}
+						} else if item := conv(value); item.IsValid() {
+							if isPtrElem {
+								ptr := reflect.New(elemT)
+								ptr.Elem().Set(item)
+								item = ptr
+							}
+							if item.Type() != elemT && !isPtrElem {
+								item = item.Convert(elemT)
+							}
+							items = append(items, item)
+						} else {
+							return ConversionError{
+								Key:   path,
+								Type:  elemT,
+								Index: key,
+							}
+						}
+					}
+				} else {
+					return ConversionError{
+						Key:   path,
+						Type:  elemT,
+						Index: key,
+					}
+				}
+			}
+		}
+		value := reflect.Append(reflect.MakeSlice(t, 0, 0), items...)
+		v.Set(value)
+	} else {
+		val := ""
+		// Use the last value provided if any values were provided
+		if len(values) > 0 {
+			val = values[len(values)-1]
+		}
+
+		if conv != nil {
+			if value := conv(val); value.IsValid() {
+				v.Set(value.Convert(t))
+			} else {
+				return ConversionError{
+					Key:   path,
+					Type:  t,
+					Index: -1,
+				}
+			}
+		} else if m.IsValid {
+			if m.IsPtr {
+				u := reflect.New(v.Type())
+				if err := u.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(val)); err != nil {
+					return ConversionError{
+						Key:   path,
+						Type:  t,
+						Index: -1,
+						Err:   err,
+					}
+				}
+				v.Set(reflect.Indirect(u))
+			} else {
+				// If the value implements the encoding.TextUnmarshaler interface
+				// apply UnmarshalText as the converter
+				if err := m.Unmarshaler.UnmarshalText([]byte(val)); err != nil {
+					return ConversionError{
+						Key:   path,
+						Type:  t,
+						Index: -1,
+						Err:   err,
+					}
+				}
+			}
+		} else if val == "" {
+			if d.zeroEmpty {
+				v.Set(reflect.Zero(t))
+			}
+		} else if conv := builtinConverters[t.Kind()]; conv != nil {
+			if value := conv(val); value.IsValid() {
+				v.Set(value.Convert(t))
+			} else {
+				return ConversionError{
+					Key:   path,
+					Type:  t,
+					Index: -1,
+				}
+			}
+		} else {
+			return fmt.Errorf("schema: converter not found for %v", t)
+		}
+	}
+	return nil
+}
+
+func isTextUnmarshaler(v reflect.Value) unmarshaler {
+	// Create a new unmarshaller instance
+	m := unmarshaler{}
+	if m.Unmarshaler, m.IsValid = v.Interface().(encoding.TextUnmarshaler); m.IsValid {
+		return m
+	}
+	// As the UnmarshalText function should be applied to the pointer of the
+	// type, we check that type to see if it implements the necessary
+	// method.
+	if m.Unmarshaler, m.IsValid = reflect.New(v.Type()).Interface().(encoding.TextUnmarshaler); m.IsValid {
+		m.IsPtr = true
+		return m
+	}
+
+	// if v is []T or *[]T create new T
+	t := v.Type()
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+	}
+	if t.Kind() == reflect.Slice {
+		// Check if the slice implements encoding.TextUnmarshaller
+		if m.Unmarshaler, m.IsValid = v.Interface().(encoding.TextUnmarshaler); m.IsValid {
+			return m
+		}
+		// If t is a pointer slice, check if its elements implement
+		// encoding.TextUnmarshaler
+		m.IsSliceElement = true
+		if t = t.Elem(); t.Kind() == reflect.Ptr {
+			t = reflect.PtrTo(t.Elem())
+			v = reflect.Zero(t)
+			m.IsSliceElementPtr = true
+			m.Unmarshaler, m.IsValid = v.Interface().(encoding.TextUnmarshaler)
+			return m
+		}
+	}
+
+	v = reflect.New(t)
+	m.Unmarshaler, m.IsValid = v.Interface().(encoding.TextUnmarshaler)
+	return m
+}
+
+// TextUnmarshaler helpers ----------------------------------------------------
+// unmarshaller contains information about a TextUnmarshaler type
+type unmarshaler struct {
+	Unmarshaler encoding.TextUnmarshaler
+	// IsValid indicates whether the resolved type indicated by the other
+	// flags implements the encoding.TextUnmarshaler interface.
+	IsValid bool
+	// IsPtr indicates that the resolved type is the pointer of the original
+	// type.
+	IsPtr bool
+	// IsSliceElement indicates that the resolved type is a slice element of
+	// the original type.
+	IsSliceElement bool
+	// IsSliceElementPtr indicates that the resolved type is a pointer to a
+	// slice element of the original type.
+	IsSliceElementPtr bool
+}
+
+// Errors ---------------------------------------------------------------------
+
+// ConversionError stores information about a failed conversion.
+type ConversionError struct {
+	Key   string       // key from the source map.
+	Type  reflect.Type // expected type of elem
+	Index int          // index for multi-value fields; -1 for single-value fields.
+	Err   error        // low-level error (when it exists)
+}
+
+func (e ConversionError) Error() string {
+	var output string
+
+	if e.Index < 0 {
+		output = fmt.Sprintf("schema: error converting value for %q", e.Key)
+	} else {
+		output = fmt.Sprintf("schema: error converting value for index %d of %q",
+			e.Index, e.Key)
+	}
+
+	if e.Err != nil {
+		output = fmt.Sprintf("%s. Details: %s", output, e.Err)
+	}
+
+	return output
+}
+
+// UnknownKeyError stores information about an unknown key in the source map.
+type UnknownKeyError struct {
+	Key string // key from the source map.
+}
+
+func (e UnknownKeyError) Error() string {
+	return fmt.Sprintf("schema: invalid path %q", e.Key)
+}
+
+// EmptyFieldError stores information about an empty required field.
+type EmptyFieldError struct {
+	Key string // required key in the source map.
+}
+
+func (e EmptyFieldError) Error() string {
+	return fmt.Sprintf("%v is empty", e.Key)
+}
+
+// MultiError stores multiple decoding errors.
+//
+// Borrowed from the App Engine SDK.
+type MultiError map[string]error
+
+func (e MultiError) Error() string {
+	s := ""
+	for _, err := range e {
+		s = err.Error()
+		break
+	}
+	switch len(e) {
+	case 0:
+		return "(0 errors)"
+	case 1:
+		return s
+	case 2:
+		return s + " (and 1 other error)"
+	}
+	return fmt.Sprintf("%s (and %d other errors)", s, len(e)-1)
+}
+
+func (e MultiError) merge(errors MultiError) {
+	for key, err := range errors {
+		if e[key] == nil {
+			e[key] = err
+		}
+	}
+}