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- // Copyright 2017 Google LLC
- //
- // Licensed under the Apache License, Version 2.0 (the "License");
- // you may not use this file except in compliance with the License.
- // You may obtain a copy of the License at
- //
- // http://www.apache.org/licenses/LICENSE-2.0
- //
- // Unless required by applicable law or agreed to in writing, software
- // distributed under the License is distributed on an "AS IS" BASIS,
- // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- // See the License for the specific language governing permissions and
- // limitations under the License.
-
- package firestore
-
- import (
- "context"
- "errors"
- "fmt"
- "io"
- "reflect"
- "sort"
-
- vkit "cloud.google.com/go/firestore/apiv1"
- "google.golang.org/api/iterator"
- pb "google.golang.org/genproto/googleapis/firestore/v1"
- "google.golang.org/grpc/codes"
- "google.golang.org/grpc/status"
- )
-
- var errNilDocRef = errors.New("firestore: nil DocumentRef")
-
- // A DocumentRef is a reference to a Firestore document.
- type DocumentRef struct {
- // The CollectionRef that this document is a part of. Never nil.
- Parent *CollectionRef
-
- // The full resource path of the document. A document "doc-1" in collection
- // "coll-1" would be: "projects/P/databases/D/documents/coll-1/doc-1".
- Path string
-
- // The shorter resource path of the document. A document "doc-1" in
- // collection "coll-1" would be: "coll-1/doc-1".
- shortPath string
-
- // The ID of the document: the last component of the resource path.
- ID string
- }
-
- func newDocRef(parent *CollectionRef, id string) *DocumentRef {
- return &DocumentRef{
- Parent: parent,
- ID: id,
- Path: parent.Path + "/" + id,
- shortPath: parent.selfPath + "/" + id,
- }
- }
-
- // Collection returns a reference to sub-collection of this document.
- func (d *DocumentRef) Collection(id string) *CollectionRef {
- return newCollRefWithParent(d.Parent.c, d, id)
- }
-
- // Get retrieves the document. If the document does not exist, Get return a NotFound error, which
- // can be checked with
- // grpc.Code(err) == codes.NotFound
- // In that case, Get returns a non-nil DocumentSnapshot whose Exists method return false and whose
- // ReadTime is the time of the failed read operation.
- func (d *DocumentRef) Get(ctx context.Context) (*DocumentSnapshot, error) {
- if d == nil {
- return nil, errNilDocRef
- }
- docsnaps, err := d.Parent.c.getAll(ctx, []*DocumentRef{d}, nil)
- if err != nil {
- return nil, err
- }
- ds := docsnaps[0]
- if !ds.Exists() {
- return ds, status.Errorf(codes.NotFound, "%q not found", d.Path)
- }
- return ds, nil
- }
-
- // Create creates the document with the given data.
- // It returns an error if a document with the same ID already exists.
- //
- // The data argument can be a map with string keys, a struct, or a pointer to a
- // struct. The map keys or exported struct fields become the fields of the firestore
- // document.
- // The values of data are converted to Firestore values as follows:
- //
- // - bool converts to Bool.
- // - string converts to String.
- // - int, int8, int16, int32 and int64 convert to Integer.
- // - uint8, uint16 and uint32 convert to Integer. uint, uint64 and uintptr are disallowed,
- // because they may be able to represent values that cannot be represented in an int64,
- // which is the underlying type of a Integer.
- // - float32 and float64 convert to Double.
- // - []byte converts to Bytes.
- // - time.Time and *ts.Timestamp convert to Timestamp. ts is the package
- // "github.com/golang/protobuf/ptypes/timestamp".
- // - *latlng.LatLng converts to GeoPoint. latlng is the package
- // "google.golang.org/genproto/googleapis/type/latlng". You should always use
- // a pointer to a LatLng.
- // - Slices convert to Array.
- // - *firestore.DocumentRef converts to Reference.
- // - Maps and structs convert to Map.
- // - nils of any type convert to Null.
- //
- // Pointers and interface{} are also permitted, and their elements processed
- // recursively.
- //
- // Struct fields can have tags like those used by the encoding/json package. Tags
- // begin with "firestore:" and are followed by "-", meaning "ignore this field," or
- // an alternative name for the field. Following the name, these comma-separated
- // options may be provided:
- //
- // - omitempty: Do not encode this field if it is empty. A value is empty
- // if it is a zero value, or an array, slice or map of length zero.
- // - serverTimestamp: The field must be of type time.Time. When writing, if
- // the field has the zero value, the server will populate the stored document with
- // the time that the request is processed.
- func (d *DocumentRef) Create(ctx context.Context, data interface{}) (*WriteResult, error) {
- ws, err := d.newCreateWrites(data)
- if err != nil {
- return nil, err
- }
- return d.Parent.c.commit1(ctx, ws)
- }
-
- func (d *DocumentRef) newCreateWrites(data interface{}) ([]*pb.Write, error) {
- if d == nil {
- return nil, errNilDocRef
- }
- doc, transforms, err := toProtoDocument(data)
- if err != nil {
- return nil, err
- }
- doc.Name = d.Path
- pc, err := exists(false).preconditionProto()
- if err != nil {
- return nil, err
- }
- return d.newUpdateWithTransform(doc, nil, pc, transforms, false), nil
- }
-
- // Set creates or overwrites the document with the given data. See DocumentRef.Create
- // for the acceptable values of data. Without options, Set overwrites the document
- // completely. Specify one of the Merge options to preserve an existing document's
- // fields. To delete some fields, use a Merge option with firestore.Delete as the
- // field value.
- func (d *DocumentRef) Set(ctx context.Context, data interface{}, opts ...SetOption) (*WriteResult, error) {
- ws, err := d.newSetWrites(data, opts)
- if err != nil {
- return nil, err
- }
- return d.Parent.c.commit1(ctx, ws)
- }
-
- func (d *DocumentRef) newSetWrites(data interface{}, opts []SetOption) ([]*pb.Write, error) {
- if d == nil {
- return nil, errNilDocRef
- }
- if data == nil {
- return nil, errors.New("firestore: nil document contents")
- }
- if len(opts) == 0 { // Set without merge
- doc, serverTimestampPaths, err := toProtoDocument(data)
- if err != nil {
- return nil, err
- }
- doc.Name = d.Path
- return d.newUpdateWithTransform(doc, nil, nil, serverTimestampPaths, true), nil
- }
- // Set with merge.
- // This is just like Update, except for the existence precondition.
- // So we turn data into a list of (FieldPath, interface{}) pairs (fpv's), as we do
- // for Update.
- fieldPaths, allPaths, err := processSetOptions(opts)
- if err != nil {
- return nil, err
- }
- var fpvs []fpv
- v := reflect.ValueOf(data)
- if allPaths {
- // Set with MergeAll. Collect all the leaves of the map.
- if v.Kind() != reflect.Map {
- return nil, errors.New("firestore: MergeAll can only be specified with map data")
- }
- if v.Len() == 0 {
- // Special case: MergeAll with an empty map.
- return d.newUpdateWithTransform(&pb.Document{Name: d.Path}, []FieldPath{}, nil, nil, true), nil
- }
- fpvsFromData(v, nil, &fpvs)
- } else {
- // Set with merge paths. Collect only the values at the given paths.
- for _, fp := range fieldPaths {
- val, err := getAtPath(v, fp)
- if err != nil {
- return nil, err
- }
- fpvs = append(fpvs, fpv{fp, val})
- }
- }
- return d.fpvsToWrites(fpvs, nil)
- }
-
- // fpvsFromData converts v into a list of (FieldPath, value) pairs.
- func fpvsFromData(v reflect.Value, prefix FieldPath, fpvs *[]fpv) {
- switch v.Kind() {
- case reflect.Map:
- for _, k := range v.MapKeys() {
- fpvsFromData(v.MapIndex(k), prefix.with(k.String()), fpvs)
- }
- case reflect.Interface:
- fpvsFromData(v.Elem(), prefix, fpvs)
-
- default:
- var val interface{}
- if v.IsValid() {
- val = v.Interface()
- }
- *fpvs = append(*fpvs, fpv{prefix, val})
- }
- }
-
- // Delete deletes the document. If the document doesn't exist, it does nothing
- // and returns no error.
- func (d *DocumentRef) Delete(ctx context.Context, preconds ...Precondition) (*WriteResult, error) {
- ws, err := d.newDeleteWrites(preconds)
- if err != nil {
- return nil, err
- }
- return d.Parent.c.commit1(ctx, ws)
- }
-
- func (d *DocumentRef) newDeleteWrites(preconds []Precondition) ([]*pb.Write, error) {
- if d == nil {
- return nil, errNilDocRef
- }
- pc, err := processPreconditionsForDelete(preconds)
- if err != nil {
- return nil, err
- }
- return []*pb.Write{{
- Operation: &pb.Write_Delete{d.Path},
- CurrentDocument: pc,
- }}, nil
- }
-
- func (d *DocumentRef) newUpdatePathWrites(updates []Update, preconds []Precondition) ([]*pb.Write, error) {
- if len(updates) == 0 {
- return nil, errors.New("firestore: no paths to update")
- }
- var fpvs []fpv
- for _, u := range updates {
- v, err := u.process()
- if err != nil {
- return nil, err
- }
- fpvs = append(fpvs, v)
- }
- pc, err := processPreconditionsForUpdate(preconds)
- if err != nil {
- return nil, err
- }
- return d.fpvsToWrites(fpvs, pc)
- }
-
- func (d *DocumentRef) fpvsToWrites(fpvs []fpv, pc *pb.Precondition) ([]*pb.Write, error) {
- // Make sure there are no duplications or prefixes among the field paths.
- var fps []FieldPath
- for _, fpv := range fpvs {
- fps = append(fps, fpv.fieldPath)
- }
- if err := checkNoDupOrPrefix(fps); err != nil {
- return nil, err
- }
-
- // Process each fpv.
- var updatePaths []FieldPath
- var transforms []*pb.DocumentTransform_FieldTransform
- doc := &pb.Document{
- Name: d.Path,
- Fields: map[string]*pb.Value{},
- }
- for _, fpv := range fpvs {
- switch fpv.value.(type) {
- case arrayUnion:
- au := fpv.value.(arrayUnion)
- t, err := arrayUnionTransform(au, fpv.fieldPath)
- if err != nil {
- return nil, err
- }
- transforms = append(transforms, t)
- case arrayRemove:
- ar := fpv.value.(arrayRemove)
- t, err := arrayRemoveTransform(ar, fpv.fieldPath)
- if err != nil {
- return nil, err
- }
- transforms = append(transforms, t)
- default:
- switch fpv.value {
- case Delete:
- // Send the field path without a corresponding value.
- updatePaths = append(updatePaths, fpv.fieldPath)
-
- case ServerTimestamp:
- // Use the path in a transform operation.
- transforms = append(transforms, serverTimestamp(fpv.fieldPath.toServiceFieldPath()))
-
- default:
- updatePaths = append(updatePaths, fpv.fieldPath)
- // Convert the value to a proto and put it into the document.
- v := reflect.ValueOf(fpv.value)
-
- pv, _, err := toProtoValue(v)
- if err != nil {
- return nil, err
- }
- setAtPath(doc.Fields, fpv.fieldPath, pv)
- // Also accumulate any transforms within the value.
- ts, err := extractTransforms(v, fpv.fieldPath)
- if err != nil {
- return nil, err
- }
- transforms = append(transforms, ts...)
- }
- }
- }
- return d.newUpdateWithTransform(doc, updatePaths, pc, transforms, false), nil
- }
-
- // newUpdateWithTransform constructs operations for a commit. Most generally, it
- // returns an update operation followed by a transform.
- //
- // If there are no serverTimestampPaths, the transform is omitted.
- //
- // If doc.Fields is empty, there are no updatePaths, and there is no precondition,
- // the update is omitted, unless updateOnEmpty is true.
- func (d *DocumentRef) newUpdateWithTransform(doc *pb.Document, updatePaths []FieldPath, pc *pb.Precondition, transforms []*pb.DocumentTransform_FieldTransform, updateOnEmpty bool) []*pb.Write {
- var ws []*pb.Write
- if updateOnEmpty || len(doc.Fields) > 0 ||
- len(updatePaths) > 0 || (pc != nil && len(transforms) == 0) {
- var mask *pb.DocumentMask
- if updatePaths != nil {
- sfps := toServiceFieldPaths(updatePaths)
- sort.Strings(sfps) // TODO(jba): make tests pass without this
- mask = &pb.DocumentMask{FieldPaths: sfps}
- }
- w := &pb.Write{
- Operation: &pb.Write_Update{doc},
- UpdateMask: mask,
- CurrentDocument: pc,
- }
- ws = append(ws, w)
- pc = nil // If the precondition is in the write, we don't need it in the transform.
- }
- if len(transforms) > 0 || pc != nil {
- ws = append(ws, &pb.Write{
- Operation: &pb.Write_Transform{
- Transform: &pb.DocumentTransform{
- Document: d.Path,
- FieldTransforms: transforms,
- },
- },
- CurrentDocument: pc,
- })
- }
- return ws
- }
-
- // arrayUnion is a special type in firestore. It instructs the server to add its
- // elements to whatever array already exists, or to create an array if no value
- // exists.
- type arrayUnion struct {
- elems []interface{}
- }
-
- // ArrayUnion specifies elements to be added to whatever array already exists in
- // the server, or to create an array if no value exists.
- //
- // If a value exists and it's an array, values are appended to it. Any duplicate
- // value is ignored.
- // If a value exists and it's not an array, the value is replaced by an array of
- // the values in the ArrayUnion.
- // If a value does not exist, an array of the values in the ArrayUnion is created.
- //
- // ArrayUnion must be the value of a field directly; it cannot appear in
- // array or struct values, or in any value that is itself inside an array or
- // struct.
- func ArrayUnion(elems ...interface{}) arrayUnion {
- return arrayUnion{elems: elems}
- }
-
- // This helper converts an arrayUnion into a proto object.
- func arrayUnionTransform(au arrayUnion, fp FieldPath) (*pb.DocumentTransform_FieldTransform, error) {
- var elems []*pb.Value
- for _, v := range au.elems {
- pv, _, err := toProtoValue(reflect.ValueOf(v))
- if err != nil {
- return nil, err
- }
- elems = append(elems, pv)
- }
- return &pb.DocumentTransform_FieldTransform{
- FieldPath: fp.toServiceFieldPath(),
- TransformType: &pb.DocumentTransform_FieldTransform_AppendMissingElements{
- AppendMissingElements: &pb.ArrayValue{Values: elems},
- },
- }, nil
- }
-
- // arrayRemove is a special type in firestore. It instructs the server to remove
- // the specified values.
- type arrayRemove struct {
- elems []interface{}
- }
-
- // ArrayRemove specifies elements to be removed from whatever array already
- // exists in the server.
- //
- // If a value exists and it's an array, values are removed from it. All
- // duplicate values are removed.
- // If a value exists and it's not an array, the value is replaced by an empty
- // array.
- // If a value does not exist, an empty array is created.
- //
- // ArrayRemove must be the value of a field directly; it cannot appear in
- // array or struct values, or in any value that is itself inside an array or
- // struct.
- func ArrayRemove(elems ...interface{}) arrayRemove {
- return arrayRemove{elems: elems}
- }
-
- // This helper converts an arrayRemove into a proto object.
- func arrayRemoveTransform(ar arrayRemove, fp FieldPath) (*pb.DocumentTransform_FieldTransform, error) {
- var elems []*pb.Value
- for _, v := range ar.elems {
- // ServerTimestamp cannot occur in an array, so we ignore transformations here.
- pv, _, err := toProtoValue(reflect.ValueOf(v))
- if err != nil {
- return nil, err
- }
- elems = append(elems, pv)
- }
- return &pb.DocumentTransform_FieldTransform{
- FieldPath: fp.toServiceFieldPath(),
- TransformType: &pb.DocumentTransform_FieldTransform_RemoveAllFromArray{
- RemoveAllFromArray: &pb.ArrayValue{Values: elems},
- },
- }, nil
- }
-
- type sentinel int
-
- const (
- // Delete is used as a value in a call to Update or Set with merge to indicate
- // that the corresponding key should be deleted.
- Delete sentinel = iota
-
- // ServerTimestamp is used as a value in a call to Update to indicate that the
- // key's value should be set to the time at which the server processed
- // the request.
- //
- // ServerTimestamp must be the value of a field directly; it cannot appear in
- // array or struct values, or in any value that is itself inside an array or
- // struct.
- ServerTimestamp
- )
-
- func (s sentinel) String() string {
- switch s {
- case Delete:
- return "Delete"
- case ServerTimestamp:
- return "ServerTimestamp"
- default:
- return "<?sentinel?>"
- }
- }
-
- // An Update describes an update to a value referred to by a path.
- // An Update should have either a non-empty Path or a non-empty FieldPath,
- // but not both.
- //
- // See DocumentRef.Create for acceptable values.
- // To delete a field, specify firestore.Delete as the value.
- type Update struct {
- Path string // Will be split on dots, and must not contain any of "˜*/[]".
- FieldPath FieldPath
- Value interface{}
- }
-
- // An fpv is a pair of validated FieldPath and value.
- type fpv struct {
- fieldPath FieldPath
- value interface{}
- }
-
- func (u *Update) process() (fpv, error) {
- if (u.Path != "") == (u.FieldPath != nil) {
- return fpv{}, fmt.Errorf("firestore: update %+v should have exactly one of Path or FieldPath", u)
- }
- fp := u.FieldPath
- var err error
- if fp == nil {
- fp, err = parseDotSeparatedString(u.Path)
- if err != nil {
- return fpv{}, err
- }
- }
- if err := fp.validate(); err != nil {
- return fpv{}, err
- }
- return fpv{fp, u.Value}, nil
- }
-
- // Update updates the document. The values at the given
- // field paths are replaced, but other fields of the stored document are untouched.
- func (d *DocumentRef) Update(ctx context.Context, updates []Update, preconds ...Precondition) (*WriteResult, error) {
- ws, err := d.newUpdatePathWrites(updates, preconds)
- if err != nil {
- return nil, err
- }
- return d.Parent.c.commit1(ctx, ws)
- }
-
- // Collections returns an interator over the immediate sub-collections of the document.
- func (d *DocumentRef) Collections(ctx context.Context) *CollectionIterator {
- client := d.Parent.c
- it := &CollectionIterator{
- client: client,
- parent: d,
- it: client.c.ListCollectionIds(
- withResourceHeader(ctx, client.path()),
- &pb.ListCollectionIdsRequest{Parent: d.Path}),
- }
- it.pageInfo, it.nextFunc = iterator.NewPageInfo(
- it.fetch,
- func() int { return len(it.items) },
- func() interface{} { b := it.items; it.items = nil; return b })
- return it
- }
-
- // CollectionIterator is an iterator over sub-collections of a document.
- type CollectionIterator struct {
- client *Client
- parent *DocumentRef
- it *vkit.StringIterator
- pageInfo *iterator.PageInfo
- nextFunc func() error
- items []*CollectionRef
- err error
- }
-
- // PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
- func (it *CollectionIterator) PageInfo() *iterator.PageInfo { return it.pageInfo }
-
- // Next returns the next result. Its second return value is iterator.Done if there
- // are no more results. Once Next returns Done, all subsequent calls will return
- // Done.
- func (it *CollectionIterator) Next() (*CollectionRef, error) {
- if err := it.nextFunc(); err != nil {
- return nil, err
- }
- item := it.items[0]
- it.items = it.items[1:]
- return item, nil
- }
-
- func (it *CollectionIterator) fetch(pageSize int, pageToken string) (string, error) {
- if it.err != nil {
- return "", it.err
- }
- return iterFetch(pageSize, pageToken, it.it.PageInfo(), func() error {
- id, err := it.it.Next()
- if err != nil {
- return err
- }
- var cr *CollectionRef
- if it.parent == nil {
- cr = newTopLevelCollRef(it.client, it.client.path(), id)
- } else {
- cr = newCollRefWithParent(it.client, it.parent, id)
- }
- it.items = append(it.items, cr)
- return nil
- })
- }
-
- // GetAll returns all the collections remaining from the iterator.
- func (it *CollectionIterator) GetAll() ([]*CollectionRef, error) {
- var crs []*CollectionRef
- for {
- cr, err := it.Next()
- if err == iterator.Done {
- break
- }
- if err != nil {
- return nil, err
- }
- crs = append(crs, cr)
- }
- return crs, nil
- }
-
- // Common fetch code for iterators that are backed by vkit iterators.
- // TODO(jba): dedup with same function in logging/logadmin.
- func iterFetch(pageSize int, pageToken string, pi *iterator.PageInfo, next func() error) (string, error) {
- pi.MaxSize = pageSize
- pi.Token = pageToken
- // Get one item, which will fill the buffer.
- if err := next(); err != nil {
- return "", err
- }
- // Collect the rest of the buffer.
- for pi.Remaining() > 0 {
- if err := next(); err != nil {
- return "", err
- }
- }
- return pi.Token, nil
- }
-
- // Snapshots returns an iterator over snapshots of the document. Each time the document
- // changes or is added or deleted, a new snapshot will be generated.
- func (d *DocumentRef) Snapshots(ctx context.Context) *DocumentSnapshotIterator {
- return &DocumentSnapshotIterator{
- docref: d,
- ws: newWatchStreamForDocument(ctx, d),
- }
- }
-
- // DocumentSnapshotIterator is an iterator over snapshots of a document.
- // Call Next on the iterator to get a snapshot of the document each time it changes.
- // Call Stop on the iterator when done.
- //
- // For an example, see DocumentRef.Snapshots.
- type DocumentSnapshotIterator struct {
- docref *DocumentRef
- ws *watchStream
- }
-
- // Next blocks until the document changes, then returns the DocumentSnapshot for
- // the current state of the document. If the document has been deleted, Next
- // returns a DocumentSnapshot whose Exists method returns false.
- //
- // Next never returns iterator.Done unless it is called after Stop.
- func (it *DocumentSnapshotIterator) Next() (*DocumentSnapshot, error) {
- btree, _, readTime, err := it.ws.nextSnapshot()
- if err != nil {
- if err == io.EOF {
- err = iterator.Done
- }
- // watchStream's error is sticky, so SnapshotIterator does not need to remember it.
- return nil, err
- }
- if btree.Len() == 0 { // document deleted
- return &DocumentSnapshot{Ref: it.docref, ReadTime: readTime}, nil
- }
- snap, _ := btree.At(0)
- return snap.(*DocumentSnapshot), nil
- }
-
- // Stop stops receiving snapshots. You should always call Stop when you are done with
- // a DocumentSnapshotIterator, to free up resources. It is not safe to call Stop
- // concurrently with Next.
- func (it *DocumentSnapshotIterator) Stop() {
- it.ws.stop()
- }
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