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Diffstat (limited to 'vendor/google.golang.org/appengine/datastore/prop.go')
| -rw-r--r-- | vendor/google.golang.org/appengine/datastore/prop.go | 330 |
1 files changed, 0 insertions, 330 deletions
diff --git a/vendor/google.golang.org/appengine/datastore/prop.go b/vendor/google.golang.org/appengine/datastore/prop.go deleted file mode 100644 index 5cb2079d8..000000000 --- a/vendor/google.golang.org/appengine/datastore/prop.go +++ /dev/null @@ -1,330 +0,0 @@ -// Copyright 2011 Google Inc. All rights reserved. -// Use of this source code is governed by the Apache 2.0 -// license that can be found in the LICENSE file. - -package datastore - -import ( - "fmt" - "reflect" - "strings" - "sync" - "unicode" -) - -// Entities with more than this many indexed properties will not be saved. -const maxIndexedProperties = 20000 - -// []byte fields more than 1 megabyte long will not be loaded or saved. -const maxBlobLen = 1 << 20 - -// Property is a name/value pair plus some metadata. A datastore entity's -// contents are loaded and saved as a sequence of Properties. An entity can -// have multiple Properties with the same name, provided that p.Multiple is -// true on all of that entity's Properties with that name. -type Property struct { - // Name is the property name. - Name string - // Value is the property value. The valid types are: - // - int64 - // - bool - // - string - // - float64 - // - ByteString - // - *Key - // - time.Time - // - appengine.BlobKey - // - appengine.GeoPoint - // - []byte (up to 1 megabyte in length) - // - *Entity (representing a nested struct) - // This set is smaller than the set of valid struct field types that the - // datastore can load and save. A Property Value cannot be a slice (apart - // from []byte); use multiple Properties instead. Also, a Value's type - // must be explicitly on the list above; it is not sufficient for the - // underlying type to be on that list. For example, a Value of "type - // myInt64 int64" is invalid. Smaller-width integers and floats are also - // invalid. Again, this is more restrictive than the set of valid struct - // field types. - // - // A Value will have an opaque type when loading entities from an index, - // such as via a projection query. Load entities into a struct instead - // of a PropertyLoadSaver when using a projection query. - // - // A Value may also be the nil interface value; this is equivalent to - // Python's None but not directly representable by a Go struct. Loading - // a nil-valued property into a struct will set that field to the zero - // value. - Value interface{} - // NoIndex is whether the datastore cannot index this property. - NoIndex bool - // Multiple is whether the entity can have multiple properties with - // the same name. Even if a particular instance only has one property with - // a certain name, Multiple should be true if a struct would best represent - // it as a field of type []T instead of type T. - Multiple bool -} - -// An Entity is the value type for a nested struct. -// This type is only used for a Property's Value. -type Entity struct { - Key *Key - Properties []Property -} - -// ByteString is a short byte slice (up to 1500 bytes) that can be indexed. -type ByteString []byte - -// PropertyLoadSaver can be converted from and to a slice of Properties. -type PropertyLoadSaver interface { - Load([]Property) error - Save() ([]Property, error) -} - -// PropertyList converts a []Property to implement PropertyLoadSaver. -type PropertyList []Property - -var ( - typeOfPropertyLoadSaver = reflect.TypeOf((*PropertyLoadSaver)(nil)).Elem() - typeOfPropertyList = reflect.TypeOf(PropertyList(nil)) -) - -// Load loads all of the provided properties into l. -// It does not first reset *l to an empty slice. -func (l *PropertyList) Load(p []Property) error { - *l = append(*l, p...) - return nil -} - -// Save saves all of l's properties as a slice or Properties. -func (l *PropertyList) Save() ([]Property, error) { - return *l, nil -} - -// validPropertyName returns whether name consists of one or more valid Go -// identifiers joined by ".". -func validPropertyName(name string) bool { - if name == "" { - return false - } - for _, s := range strings.Split(name, ".") { - if s == "" { - return false - } - first := true - for _, c := range s { - if first { - first = false - if c != '_' && !unicode.IsLetter(c) { - return false - } - } else { - if c != '_' && !unicode.IsLetter(c) && !unicode.IsDigit(c) { - return false - } - } - } - } - return true -} - -// structCodec describes how to convert a struct to and from a sequence of -// properties. -type structCodec struct { - // fields gives the field codec for the structTag with the given name. - fields map[string]fieldCodec - // hasSlice is whether a struct or any of its nested or embedded structs - // has a slice-typed field (other than []byte). - hasSlice bool - // keyField is the index of a *Key field with structTag __key__. - // This field is not relevant for the top level struct, only for - // nested structs. - keyField int - // complete is whether the structCodec is complete. An incomplete - // structCodec may be encountered when walking a recursive struct. - complete bool -} - -// fieldCodec is a struct field's index and, if that struct field's type is -// itself a struct, that substruct's structCodec. -type fieldCodec struct { - // path is the index path to the field - path []int - noIndex bool - // omitEmpty indicates that the field should be omitted on save - // if empty. - omitEmpty bool - // structCodec is the codec fot the struct field at index 'path', - // or nil if the field is not a struct. - structCodec *structCodec -} - -// structCodecs collects the structCodecs that have already been calculated. -var ( - structCodecsMutex sync.Mutex - structCodecs = make(map[reflect.Type]*structCodec) -) - -// getStructCodec returns the structCodec for the given struct type. -func getStructCodec(t reflect.Type) (*structCodec, error) { - structCodecsMutex.Lock() - defer structCodecsMutex.Unlock() - return getStructCodecLocked(t) -} - -// getStructCodecLocked implements getStructCodec. The structCodecsMutex must -// be held when calling this function. -func getStructCodecLocked(t reflect.Type) (ret *structCodec, retErr error) { - c, ok := structCodecs[t] - if ok { - return c, nil - } - c = &structCodec{ - fields: make(map[string]fieldCodec), - // We initialize keyField to -1 so that the zero-value is not - // misinterpreted as index 0. - keyField: -1, - } - - // Add c to the structCodecs map before we are sure it is good. If t is - // a recursive type, it needs to find the incomplete entry for itself in - // the map. - structCodecs[t] = c - defer func() { - if retErr != nil { - delete(structCodecs, t) - } - }() - - for i := 0; i < t.NumField(); i++ { - f := t.Field(i) - // Skip unexported fields. - // Note that if f is an anonymous, unexported struct field, - // we will promote its fields. - if f.PkgPath != "" && !f.Anonymous { - continue - } - - tags := strings.Split(f.Tag.Get("datastore"), ",") - name := tags[0] - opts := make(map[string]bool) - for _, t := range tags[1:] { - opts[t] = true - } - switch { - case name == "": - if !f.Anonymous { - name = f.Name - } - case name == "-": - continue - case name == "__key__": - if f.Type != typeOfKeyPtr { - return nil, fmt.Errorf("datastore: __key__ field on struct %v is not a *datastore.Key", t) - } - c.keyField = i - case !validPropertyName(name): - return nil, fmt.Errorf("datastore: struct tag has invalid property name: %q", name) - } - - substructType, fIsSlice := reflect.Type(nil), false - switch f.Type.Kind() { - case reflect.Struct: - substructType = f.Type - case reflect.Slice: - if f.Type.Elem().Kind() == reflect.Struct { - substructType = f.Type.Elem() - } - fIsSlice = f.Type != typeOfByteSlice - c.hasSlice = c.hasSlice || fIsSlice - } - - var sub *structCodec - if substructType != nil && substructType != typeOfTime && substructType != typeOfGeoPoint { - var err error - sub, err = getStructCodecLocked(substructType) - if err != nil { - return nil, err - } - if !sub.complete { - return nil, fmt.Errorf("datastore: recursive struct: field %q", f.Name) - } - if fIsSlice && sub.hasSlice { - return nil, fmt.Errorf( - "datastore: flattening nested structs leads to a slice of slices: field %q", f.Name) - } - c.hasSlice = c.hasSlice || sub.hasSlice - // If f is an anonymous struct field, we promote the substruct's fields up to this level - // in the linked list of struct codecs. - if f.Anonymous { - for subname, subfield := range sub.fields { - if name != "" { - subname = name + "." + subname - } - if _, ok := c.fields[subname]; ok { - return nil, fmt.Errorf("datastore: struct tag has repeated property name: %q", subname) - } - c.fields[subname] = fieldCodec{ - path: append([]int{i}, subfield.path...), - noIndex: subfield.noIndex || opts["noindex"], - omitEmpty: subfield.omitEmpty, - structCodec: subfield.structCodec, - } - } - continue - } - } - - if _, ok := c.fields[name]; ok { - return nil, fmt.Errorf("datastore: struct tag has repeated property name: %q", name) - } - c.fields[name] = fieldCodec{ - path: []int{i}, - noIndex: opts["noindex"], - omitEmpty: opts["omitempty"], - structCodec: sub, - } - } - c.complete = true - return c, nil -} - -// structPLS adapts a struct to be a PropertyLoadSaver. -type structPLS struct { - v reflect.Value - codec *structCodec -} - -// newStructPLS returns a structPLS, which implements the -// PropertyLoadSaver interface, for the struct pointer p. -func newStructPLS(p interface{}) (*structPLS, error) { - v := reflect.ValueOf(p) - if v.Kind() != reflect.Ptr || v.Elem().Kind() != reflect.Struct { - return nil, ErrInvalidEntityType - } - v = v.Elem() - codec, err := getStructCodec(v.Type()) - if err != nil { - return nil, err - } - return &structPLS{v, codec}, nil -} - -// LoadStruct loads the properties from p to dst. -// dst must be a struct pointer. -func LoadStruct(dst interface{}, p []Property) error { - x, err := newStructPLS(dst) - if err != nil { - return err - } - return x.Load(p) -} - -// SaveStruct returns the properties from src as a slice of Properties. -// src must be a struct pointer. -func SaveStruct(src interface{}) ([]Property, error) { - x, err := newStructPLS(src) - if err != nil { - return nil, err - } - return x.Save() -} |