blob: 4d8c4671e75263872a26582ea989eb93c692ce06 [file] [log] [blame]
/*
* Copyright 2018-present Open Networking Foundation
* 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 model
// TODO: proper error handling
// TODO: proper logging
import (
"context"
"fmt"
"github.com/golang/protobuf/proto"
"github.com/opencord/voltha-lib-go/pkg/common/log"
"reflect"
"strings"
"sync"
"time"
)
// When a branch has no transaction id, everything gets stored in NONE
const (
NONE string = "none"
)
// Node interface is an abstraction of the node data structure
type Node interface {
MakeLatest(branch *Branch, revision Revision, changeAnnouncement []ChangeTuple)
// CRUD functions
Add(ctx context.Context, path string, data interface{}, txid string, makeBranch MakeBranchFunction) Revision
Get(ctx context.Context, path string, hash string, depth int, deep bool, txid string) interface{}
List(ctx context.Context, path string, hash string, depth int, deep bool, txid string) interface{}
Update(ctx context.Context, path string, data interface{}, strict bool, txid string, makeBranch MakeBranchFunction) Revision
Remove(ctx context.Context, path string, txid string, makeBranch MakeBranchFunction) Revision
CreateProxy(ctx context.Context, path string, exclusive bool) *Proxy
GetProxy() *Proxy
MakeBranch(txid string) *Branch
DeleteBranch(txid string)
MergeBranch(txid string, dryRun bool) (Revision, error)
MakeTxBranch() string
DeleteTxBranch(txid string)
FoldTxBranch(txid string)
}
type node struct {
mutex sync.RWMutex
Root *root
Type interface{}
Branches map[string]*Branch
Tags map[string]Revision
Proxy *Proxy
EventBus *EventBus
AutoPrune bool
}
// ChangeTuple holds details of modifications made to a revision
type ChangeTuple struct {
Type CallbackType
PreviousData interface{}
LatestData interface{}
}
// NewNode creates a new instance of the node data structure
func NewNode(root *root, initialData interface{}, autoPrune bool, txid string) *node {
n := &node{}
n.Root = root
n.Branches = make(map[string]*Branch)
n.Tags = make(map[string]Revision)
n.Proxy = nil
n.EventBus = nil
n.AutoPrune = autoPrune
if IsProtoMessage(initialData) {
n.Type = reflect.ValueOf(initialData).Interface()
dataCopy := proto.Clone(initialData.(proto.Message))
n.initialize(dataCopy, txid)
} else if reflect.ValueOf(initialData).IsValid() {
// FIXME: this block does not reflect the original implementation
// it should be checking if the provided initial_data is already a type!??!
// it should be checked before IsProtoMessage
n.Type = reflect.ValueOf(initialData).Interface()
} else {
// not implemented error
log.Errorf("cannot process initial data - %+v", initialData)
}
return n
}
// MakeNode creates a new node in the tree
func (n *node) MakeNode(data interface{}, txid string) *node {
return NewNode(n.Root, data, true, txid)
}
// MakeRevision create a new revision of the node in the tree
func (n *node) MakeRevision(branch *Branch, data interface{}, children map[string][]Revision) Revision {
return n.GetRoot().MakeRevision(branch, data, children)
}
// makeLatest will mark the revision of a node as being the latest
func (n *node) makeLatest(branch *Branch, revision Revision, changeAnnouncement []ChangeTuple) {
// Keep a reference to the current revision
var previous string
if branch.GetLatest() != nil {
previous = branch.GetLatest().GetHash()
}
branch.AddRevision(revision)
// If anything is new, then set the revision as the latest
if branch.GetLatest() == nil || revision.GetHash() != branch.GetLatest().GetHash() {
if revision.GetName() != "" {
log.Debugw("saving-latest-data", log.Fields{"hash": revision.GetHash(), "data": revision.GetData()})
// Tag a timestamp to that revision
revision.SetLastUpdate()
GetRevCache().Set(revision.GetName(), revision)
}
branch.SetLatest(revision)
}
// Delete the previous revision if anything has changed
if previous != "" && previous != branch.GetLatest().GetHash() {
branch.DeleteRevision(previous)
}
if changeAnnouncement != nil && branch.Txid == "" {
if n.Proxy != nil {
for _, change := range changeAnnouncement {
log.Debugw("adding-callback",
log.Fields{
"callbacks": n.GetProxy().getCallbacks(change.Type),
"type": change.Type,
"previousData": change.PreviousData,
"latestData": change.LatestData,
})
n.Root.AddCallback(
n.GetProxy().InvokeCallbacks,
change.Type,
true,
change.PreviousData,
change.LatestData)
}
}
}
}
// Latest returns the latest revision of node with or without the transaction id
func (n *node) Latest(txid ...string) Revision {
var branch *Branch
if len(txid) > 0 && txid[0] != "" {
if branch = n.GetBranch(txid[0]); branch != nil {
return branch.GetLatest()
}
} else if branch = n.GetBranch(NONE); branch != nil {
return branch.GetLatest()
}
return nil
}
// initialize prepares the content of a node along with its possible ramifications
func (n *node) initialize(data interface{}, txid string) {
children := make(map[string][]Revision)
for fieldName, field := range ChildrenFields(n.Type) {
_, fieldValue := GetAttributeValue(data, fieldName, 0)
if fieldValue.IsValid() {
if field.IsContainer {
if field.Key != "" {
for i := 0; i < fieldValue.Len(); i++ {
v := fieldValue.Index(i)
if rev := n.MakeNode(v.Interface(), txid).Latest(txid); rev != nil {
children[fieldName] = append(children[fieldName], rev)
}
// TODO: The following logic was ported from v1.0. Need to verify if it is required
//var keysSeen []string
//_, key := GetAttributeValue(v.Interface(), field.Key, 0)
//for _, k := range keysSeen {
// if k == key.String() {
// //log.Errorf("duplicate key - %s", k)
// }
//}
//keysSeen = append(keysSeen, key.String())
}
} else {
for i := 0; i < fieldValue.Len(); i++ {
v := fieldValue.Index(i)
if newNodeRev := n.MakeNode(v.Interface(), txid).Latest(); newNodeRev != nil {
children[fieldName] = append(children[fieldName], newNodeRev)
}
}
}
} else {
if newNodeRev := n.MakeNode(fieldValue.Interface(), txid).Latest(); newNodeRev != nil {
children[fieldName] = append(children[fieldName], newNodeRev)
}
}
} else {
log.Errorf("field is invalid - %+v", fieldValue)
}
}
branch := NewBranch(n, "", nil, n.AutoPrune)
rev := n.MakeRevision(branch, data, children)
n.makeLatest(branch, rev, nil)
if txid == "" {
n.SetBranch(NONE, branch)
} else {
n.SetBranch(txid, branch)
}
}
// findRevByKey retrieves a specific revision from a node tree
func (n *node) findRevByKey(revs []Revision, keyName string, value interface{}) (int, Revision) {
for i, rev := range revs {
dataValue := reflect.ValueOf(rev.GetData())
dataStruct := GetAttributeStructure(rev.GetData(), keyName, 0)
fieldValue := dataValue.Elem().FieldByName(dataStruct.Name)
a := fmt.Sprintf("%s", fieldValue.Interface())
b := fmt.Sprintf("%s", value)
if a == b {
return i, revs[i]
}
}
return -1, nil
}
// Get retrieves the data from a node tree that resides at the specified path
func (n *node) List(ctx context.Context, path string, hash string, depth int, deep bool, txid string) interface{} {
n.mutex.Lock()
defer n.mutex.Unlock()
log.Debugw("node-list-request", log.Fields{"path": path, "hash": hash, "depth": depth, "deep": deep, "txid": txid})
if deep {
depth = -1
}
for strings.HasPrefix(path, "/") {
path = path[1:]
}
var branch *Branch
var rev Revision
if branch = n.GetBranch(txid); txid == "" || branch == nil {
branch = n.GetBranch(NONE)
}
if hash != "" {
rev = branch.GetRevision(hash)
} else {
rev = branch.GetLatest()
}
var result interface{}
var prList []interface{}
if pr := rev.LoadFromPersistence(ctx, path, txid, nil); pr != nil {
for _, revEntry := range pr {
prList = append(prList, revEntry.GetData())
}
result = prList
}
return result
}
// Get retrieves the data from a node tree that resides at the specified path
func (n *node) Get(ctx context.Context, path string, hash string, depth int, reconcile bool, txid string) interface{} {
n.mutex.Lock()
defer n.mutex.Unlock()
log.Debugw("node-get-request", log.Fields{"path": path, "hash": hash, "depth": depth, "reconcile": reconcile, "txid": txid})
for strings.HasPrefix(path, "/") {
path = path[1:]
}
var branch *Branch
var rev Revision
if branch = n.GetBranch(txid); txid == "" || branch == nil {
branch = n.GetBranch(NONE)
}
if hash != "" {
rev = branch.GetRevision(hash)
} else {
rev = branch.GetLatest()
}
var result interface{}
// If there is no request to reconcile, try to get it from memory
if !reconcile {
// Try to find an entry matching the path value from one of these sources
// 1. Start with the cache which stores revisions by watch names
// 2. Then look in the revision tree, especially if it's a sub-path such as /devices/1234/flows
// 3. Move on to the KV store if that path cannot be found or if the entry has expired
if entry, exists := GetRevCache().Get(path); exists && entry.(Revision) != nil {
entryAge := time.Now().Sub(entry.(Revision).GetLastUpdate()).Nanoseconds() / int64(time.Millisecond)
if entryAge < DataRefreshPeriod {
log.Debugw("using-cache-entry", log.Fields{
"path": path,
"hash": hash,
"age": entryAge,
})
return proto.Clone(entry.(Revision).GetData().(proto.Message))
} else {
log.Debugw("cache-entry-expired", log.Fields{"path": path, "hash": hash, "age": entryAge})
}
} else if result = n.getPath(ctx, rev.GetBranch().GetLatest(), path, depth); result != nil && reflect.ValueOf(result).IsValid() && !reflect.ValueOf(result).IsNil() {
log.Debugw("using-rev-tree-entry", log.Fields{"path": path, "hash": hash, "depth": depth, "reconcile": reconcile, "txid": txid})
return result
} else {
log.Debugw("not-using-cache-entry", log.Fields{
"path": path,
"hash": hash, "depth": depth,
"reconcile": reconcile,
"txid": txid,
})
}
} else {
log.Debugw("reconcile-requested", log.Fields{
"path": path,
"hash": hash,
"reconcile": reconcile,
})
}
// If we got to this point, we are either trying to reconcile with the db
// or we simply failed at getting information from memory
if n.Root.KvStore != nil {
if pr := rev.LoadFromPersistence(ctx, path, txid, nil); pr != nil && len(pr) > 0 {
// Did we receive a single or multiple revisions?
if len(pr) > 1 {
var revs []interface{}
for _, revEntry := range pr {
revs = append(revs, revEntry.GetData())
}
result = revs
} else {
result = pr[0].GetData()
}
}
}
return result
}
//getPath traverses the specified path and retrieves the data associated to it
func (n *node) getPath(ctx context.Context, rev Revision, path string, depth int) interface{} {
if path == "" {
return n.getData(rev, depth)
}
partition := strings.SplitN(path, "/", 2)
name := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
names := ChildrenFields(n.Type)
field := names[name]
if field != nil && field.IsContainer {
children := make([]Revision, len(rev.GetChildren(name)))
copy(children, rev.GetChildren(name))
if field.Key != "" {
if path != "" {
partition = strings.SplitN(path, "/", 2)
key := partition[0]
path = ""
keyValue := field.KeyFromStr(key)
if _, childRev := n.findRevByKey(children, field.Key, keyValue); childRev == nil {
return nil
} else {
childNode := childRev.GetNode()
return childNode.getPath(ctx, childRev, path, depth)
}
} else {
var response []interface{}
for _, childRev := range children {
childNode := childRev.GetNode()
value := childNode.getData(childRev, depth)
response = append(response, value)
}
return response
}
} else {
var response []interface{}
if path != "" {
// TODO: raise error
return response
}
for _, childRev := range children {
childNode := childRev.GetNode()
value := childNode.getData(childRev, depth)
response = append(response, value)
}
return response
}
} else if children := rev.GetChildren(name); children != nil && len(children) > 0 {
childRev := children[0]
childNode := childRev.GetNode()
return childNode.getPath(ctx, childRev, path, depth)
}
return nil
}
// getData retrieves the data from a node revision
func (n *node) getData(rev Revision, depth int) interface{} {
msg := rev.GetBranch().GetLatest().Get(depth)
var modifiedMsg interface{}
if n.GetProxy() != nil {
log.Debugw("invoking-get-callbacks", log.Fields{"data": msg})
if modifiedMsg = n.GetProxy().InvokeCallbacks(GET, false, msg); modifiedMsg != nil {
msg = modifiedMsg
}
}
return msg
}
// Update changes the content of a node at the specified path with the provided data
func (n *node) Update(ctx context.Context, path string, data interface{}, strict bool, txid string, makeBranch MakeBranchFunction) Revision {
n.mutex.Lock()
defer n.mutex.Unlock()
log.Debugw("node-update-request", log.Fields{"path": path, "strict": strict, "txid": txid})
for strings.HasPrefix(path, "/") {
path = path[1:]
}
var branch *Branch
if txid == "" {
branch = n.GetBranch(NONE)
} else if branch = n.GetBranch(txid); branch == nil {
branch = makeBranch(n)
}
if branch.GetLatest() != nil {
log.Debugf("Branch data : %+v, Passed data: %+v", branch.GetLatest().GetData(), data)
}
if path == "" {
return n.doUpdate(ctx, branch, data, strict)
}
rev := branch.GetLatest()
partition := strings.SplitN(path, "/", 2)
name := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
field := ChildrenFields(n.Type)[name]
var children []Revision
if field == nil {
return n.doUpdate(ctx, branch, data, strict)
}
if field.IsContainer {
if path == "" {
log.Errorf("cannot update a list")
} else if field.Key != "" {
partition := strings.SplitN(path, "/", 2)
key := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
keyValue := field.KeyFromStr(key)
children = make([]Revision, len(rev.GetChildren(name)))
copy(children, rev.GetChildren(name))
idx, childRev := n.findRevByKey(children, field.Key, keyValue)
if childRev == nil {
log.Debugw("child-revision-is-nil", log.Fields{"key": keyValue})
return branch.GetLatest()
}
childNode := childRev.GetNode()
// Save proxy in child node to ensure callbacks are called later on
// only assign in cases of non sub-folder proxies, i.e. "/"
if childNode.Proxy == nil && n.Proxy != nil && n.GetProxy().getFullPath() == "" {
childNode.Proxy = n.Proxy
}
newChildRev := childNode.Update(ctx, path, data, strict, txid, makeBranch)
if newChildRev.GetHash() == childRev.GetHash() {
if newChildRev != childRev {
log.Debug("clear-hash - %s %+v", newChildRev.GetHash(), newChildRev)
newChildRev.ClearHash()
}
log.Debugw("child-revisions-have-matching-hash", log.Fields{"hash": childRev.GetHash(), "key": keyValue})
return branch.GetLatest()
}
_, newKey := GetAttributeValue(newChildRev.GetData(), field.Key, 0)
_newKeyType := fmt.Sprintf("%s", newKey)
_keyValueType := fmt.Sprintf("%s", keyValue)
if _newKeyType != _keyValueType {
log.Errorf("cannot change key field")
}
// Prefix the hash value with the data type (e.g. devices, logical_devices, adapters)
newChildRev.SetName(name + "/" + _keyValueType)
branch.LatestLock.Lock()
defer branch.LatestLock.Unlock()
if idx >= 0 {
children[idx] = newChildRev
} else {
children = append(children, newChildRev)
}
updatedRev := rev.UpdateChildren(ctx, name, children, branch)
n.makeLatest(branch, updatedRev, nil)
updatedRev.ChildDrop(name, childRev.GetHash())
return newChildRev
} else {
log.Errorf("cannot index into container with no keys")
}
} else {
childRev := rev.GetChildren(name)[0]
childNode := childRev.GetNode()
newChildRev := childNode.Update(ctx, path, data, strict, txid, makeBranch)
branch.LatestLock.Lock()
defer branch.LatestLock.Unlock()
updatedRev := rev.UpdateChildren(ctx, name, []Revision{newChildRev}, branch)
n.makeLatest(branch, updatedRev, nil)
updatedRev.ChildDrop(name, childRev.GetHash())
return newChildRev
}
return nil
}
func (n *node) doUpdate(ctx context.Context, branch *Branch, data interface{}, strict bool) Revision {
log.Debugw("comparing-types", log.Fields{"expected": reflect.ValueOf(n.Type).Type(), "actual": reflect.TypeOf(data)})
if reflect.TypeOf(data) != reflect.ValueOf(n.Type).Type() {
// TODO raise error
log.Errorw("types-do-not-match: %+v", log.Fields{"actual": reflect.TypeOf(data), "expected": n.Type})
return nil
}
// TODO: validate that this actually works
//if n.hasChildren(data) {
// return nil
//}
if n.GetProxy() != nil {
log.Debug("invoking proxy PRE_UPDATE Callbacks")
n.GetProxy().InvokeCallbacks(PRE_UPDATE, false, branch.GetLatest(), data)
}
if branch.GetLatest().GetData().(proto.Message).String() != data.(proto.Message).String() {
if strict {
// TODO: checkAccessViolations(data, Branch.GetLatest.data)
log.Debugf("checking access violations")
}
rev := branch.GetLatest().UpdateData(ctx, data, branch)
changes := []ChangeTuple{{POST_UPDATE, branch.GetLatest().GetData(), rev.GetData()}}
n.makeLatest(branch, rev, changes)
return rev
}
return branch.GetLatest()
}
// Add inserts a new node at the specified path with the provided data
func (n *node) Add(ctx context.Context, path string, data interface{}, txid string, makeBranch MakeBranchFunction) Revision {
n.mutex.Lock()
defer n.mutex.Unlock()
log.Debugw("node-add-request", log.Fields{"path": path, "txid": txid})
for strings.HasPrefix(path, "/") {
path = path[1:]
}
if path == "" {
// TODO raise error
log.Errorf("cannot add for non-container mode")
return nil
}
var branch *Branch
if txid == "" {
branch = n.GetBranch(NONE)
} else if branch = n.GetBranch(txid); branch == nil {
branch = makeBranch(n)
}
rev := branch.GetLatest()
partition := strings.SplitN(path, "/", 2)
name := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
field := ChildrenFields(n.Type)[name]
var children []Revision
if field.IsContainer {
if path == "" {
if field.Key != "" {
if n.GetProxy() != nil {
log.Debug("invoking proxy PRE_ADD Callbacks")
n.GetProxy().InvokeCallbacks(PRE_ADD, false, data)
}
children = make([]Revision, len(rev.GetChildren(name)))
copy(children, rev.GetChildren(name))
_, key := GetAttributeValue(data, field.Key, 0)
if _, exists := n.findRevByKey(children, field.Key, key.String()); exists != nil {
// TODO raise error
log.Warnw("duplicate-key-found", log.Fields{"key": key.String()})
return exists
}
childRev := n.MakeNode(data, "").Latest()
// Prefix the hash with the data type (e.g. devices, logical_devices, adapters)
childRev.SetName(name + "/" + key.String())
branch.LatestLock.Lock()
defer branch.LatestLock.Unlock()
children = append(children, childRev)
updatedRev := rev.UpdateChildren(ctx, name, children, branch)
changes := []ChangeTuple{{POST_ADD, nil, childRev.GetData()}}
childRev.SetupWatch(childRev.GetName())
n.makeLatest(branch, updatedRev, changes)
return childRev
}
log.Errorf("cannot add to non-keyed container")
} else if field.Key != "" {
partition := strings.SplitN(path, "/", 2)
key := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
keyValue := field.KeyFromStr(key)
children = make([]Revision, len(rev.GetChildren(name)))
copy(children, rev.GetChildren(name))
idx, childRev := n.findRevByKey(children, field.Key, keyValue)
if childRev == nil {
return branch.GetLatest()
}
childNode := childRev.GetNode()
newChildRev := childNode.Add(ctx, path, data, txid, makeBranch)
// Prefix the hash with the data type (e.g. devices, logical_devices, adapters)
newChildRev.SetName(name + "/" + keyValue.(string))
branch.LatestLock.Lock()
defer branch.LatestLock.Unlock()
if idx >= 0 {
children[idx] = newChildRev
} else {
children = append(children, newChildRev)
}
updatedRev := rev.UpdateChildren(ctx, name, children, branch)
n.makeLatest(branch, updatedRev, nil)
updatedRev.ChildDrop(name, childRev.GetHash())
return newChildRev
} else {
log.Errorf("cannot add to non-keyed container")
}
} else {
log.Errorf("cannot add to non-container field")
}
return nil
}
// Remove eliminates a node at the specified path
func (n *node) Remove(ctx context.Context, path string, txid string, makeBranch MakeBranchFunction) Revision {
n.mutex.Lock()
defer n.mutex.Unlock()
log.Debugw("node-remove-request", log.Fields{"path": path, "txid": txid, "makeBranch": makeBranch})
for strings.HasPrefix(path, "/") {
path = path[1:]
}
if path == "" {
// TODO raise error
log.Errorf("cannot remove for non-container mode")
}
var branch *Branch
if txid == "" {
branch = n.GetBranch(NONE)
} else if branch = n.GetBranch(txid); branch == nil {
branch = makeBranch(n)
}
rev := branch.GetLatest()
partition := strings.SplitN(path, "/", 2)
name := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
field := ChildrenFields(n.Type)[name]
var children []Revision
postAnnouncement := []ChangeTuple{}
if field.IsContainer {
if path == "" {
log.Errorw("cannot-remove-without-key", log.Fields{"name": name, "key": path})
} else if field.Key != "" {
partition := strings.SplitN(path, "/", 2)
key := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
keyValue := field.KeyFromStr(key)
children = make([]Revision, len(rev.GetChildren(name)))
copy(children, rev.GetChildren(name))
if path != "" {
if idx, childRev := n.findRevByKey(children, field.Key, keyValue); childRev != nil {
childNode := childRev.GetNode()
if childNode.Proxy == nil {
childNode.Proxy = n.Proxy
}
newChildRev := childNode.Remove(ctx, path, txid, makeBranch)
branch.LatestLock.Lock()
defer branch.LatestLock.Unlock()
if idx >= 0 {
children[idx] = newChildRev
} else {
children = append(children, newChildRev)
}
rev.SetChildren(name, children)
branch.GetLatest().Drop(txid, false)
n.makeLatest(branch, rev, nil)
}
return branch.GetLatest()
}
if idx, childRev := n.findRevByKey(children, field.Key, keyValue); childRev != nil && idx >= 0 {
if n.GetProxy() != nil {
data := childRev.GetData()
n.GetProxy().InvokeCallbacks(PRE_REMOVE, false, data)
postAnnouncement = append(postAnnouncement, ChangeTuple{POST_REMOVE, data, nil})
} else {
postAnnouncement = append(postAnnouncement, ChangeTuple{POST_REMOVE, childRev.GetData(), nil})
}
childRev.StorageDrop(txid, true)
GetRevCache().Delete(childRev.GetName())
branch.LatestLock.Lock()
defer branch.LatestLock.Unlock()
children = append(children[:idx], children[idx+1:]...)
rev.SetChildren(name, children)
branch.GetLatest().Drop(txid, false)
n.makeLatest(branch, rev, postAnnouncement)
return rev
} else {
log.Errorw("failed-to-find-revision", log.Fields{"name": name, "key": keyValue.(string)})
}
}
log.Errorw("cannot-add-to-non-keyed-container", log.Fields{"name": name, "path": path, "fieldKey": field.Key})
} else {
log.Errorw("cannot-add-to-non-container-field", log.Fields{"name": name, "path": path})
}
return nil
}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Branching ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// MakeBranchFunction is a type for function references intented to create a branch
type MakeBranchFunction func(*node) *Branch
// MakeBranch creates a new branch for the provided transaction id
func (n *node) MakeBranch(txid string) *Branch {
branchPoint := n.GetBranch(NONE).GetLatest()
branch := NewBranch(n, txid, branchPoint, true)
n.SetBranch(txid, branch)
return branch
}
// DeleteBranch removes a branch with the specified id
func (n *node) DeleteBranch(txid string) {
delete(n.Branches, txid)
}
func (n *node) mergeChild(txid string, dryRun bool) func(Revision) Revision {
f := func(rev Revision) Revision {
childBranch := rev.GetBranch()
if childBranch.Txid == txid {
rev, _ = childBranch.Node.MergeBranch(txid, dryRun)
}
return rev
}
return f
}
// MergeBranch will integrate the contents of a transaction branch within the latest branch of a given node
func (n *node) MergeBranch(txid string, dryRun bool) (Revision, error) {
srcBranch := n.GetBranch(txid)
dstBranch := n.GetBranch(NONE)
forkRev := srcBranch.Origin
srcRev := srcBranch.GetLatest()
dstRev := dstBranch.GetLatest()
rev, changes := Merge3Way(forkRev, srcRev, dstRev, n.mergeChild(txid, dryRun), dryRun)
if !dryRun {
if rev != nil {
rev.SetName(dstRev.GetName())
n.makeLatest(dstBranch, rev, changes)
}
n.DeleteBranch(txid)
}
// TODO: return proper error when one occurs
return rev, nil
}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Diff utility ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//func (n *node) diff(hash1, hash2, txid string) {
// branch := n.Branches[txid]
// rev1 := branch.GetHash(hash1)
// rev2 := branch.GetHash(hash2)
//
// if rev1.GetHash() == rev2.GetHash() {
// // empty patch
// } else {
// // translate data to json and generate patch
// patch, err := jsonpatch.MakePatch(rev1.GetData(), rev2.GetData())
// patch.
// }
//}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Tag utility ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// TODO: is tag mgmt used in the python implementation? Need to validate
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Internals ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
func (n *node) hasChildren(data interface{}) bool {
for fieldName, field := range ChildrenFields(n.Type) {
_, fieldValue := GetAttributeValue(data, fieldName, 0)
if (field.IsContainer && fieldValue.Len() > 0) || !fieldValue.IsNil() {
log.Error("cannot update external children")
return true
}
}
return false
}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ node Proxy ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// CreateProxy returns a reference to a sub-tree of the data model
func (n *node) CreateProxy(ctx context.Context, path string, exclusive bool) *Proxy {
return n.createProxy(ctx, path, path, n, exclusive)
}
func (n *node) createProxy(ctx context.Context, path string, fullPath string, parentNode *node, exclusive bool) *Proxy {
log.Debugw("node-create-proxy", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"fullPath": fullPath,
})
for strings.HasPrefix(path, "/") {
path = path[1:]
}
if path == "" {
return n.makeProxy(path, fullPath, parentNode, exclusive)
}
rev := n.GetBranch(NONE).GetLatest()
partition := strings.SplitN(path, "/", 2)
name := partition[0]
var nodeType interface{}
if len(partition) < 2 {
path = ""
nodeType = n.Type
} else {
path = partition[1]
nodeType = parentNode.Type
}
field := ChildrenFields(nodeType)[name]
if field != nil {
if field.IsContainer {
log.Debugw("container-field", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"name": name,
})
if path == "" {
log.Debugw("folder-proxy", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"fullPath": fullPath,
"name": name,
})
newNode := n.MakeNode(reflect.New(field.ClassType.Elem()).Interface(), "")
return newNode.makeProxy(path, fullPath, parentNode, exclusive)
} else if field.Key != "" {
log.Debugw("key-proxy", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"fullPath": fullPath,
"name": name,
})
partition := strings.SplitN(path, "/", 2)
key := partition[0]
if len(partition) < 2 {
path = ""
} else {
path = partition[1]
}
keyValue := field.KeyFromStr(key)
var children []Revision
children = make([]Revision, len(rev.GetChildren(name)))
copy(children, rev.GetChildren(name))
var childRev Revision
if _, childRev = n.findRevByKey(children, field.Key, keyValue); childRev != nil {
log.Debugw("found-revision-matching-key-in-memory", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"fullPath": fullPath,
"name": name,
})
} else if revs := n.GetBranch(NONE).GetLatest().LoadFromPersistence(ctx, fullPath, "", nil); revs != nil && len(revs) > 0 {
log.Debugw("found-revision-matching-key-in-db", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"fullPath": fullPath,
"name": name,
})
childRev = revs[0]
} else {
log.Debugw("no-revision-matching-key", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"fullPath": fullPath,
"name": name,
})
}
if childRev != nil {
childNode := childRev.GetNode()
return childNode.createProxy(ctx, path, fullPath, n, exclusive)
}
} else {
log.Errorw("cannot-access-index-of-empty-container", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"name": name,
})
}
} else {
log.Debugw("non-container-field", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"name": name,
})
childRev := rev.GetChildren(name)[0]
childNode := childRev.GetNode()
return childNode.createProxy(ctx, path, fullPath, n, exclusive)
}
} else {
log.Debugw("field-object-is-nil", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"fullPath": fullPath,
"name": name,
})
}
log.Warnw("cannot-create-proxy", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"fullPath": fullPath,
"latest-rev": rev.GetHash(),
})
return nil
}
func (n *node) makeProxy(path string, fullPath string, parentNode *node, exclusive bool) *Proxy {
log.Debugw("node-make-proxy", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"fullPath": fullPath,
})
r := &root{
node: n,
Callbacks: n.Root.GetCallbacks(),
NotificationCallbacks: n.Root.GetNotificationCallbacks(),
DirtyNodes: n.Root.DirtyNodes,
KvStore: n.Root.KvStore,
Loading: n.Root.Loading,
RevisionClass: n.Root.RevisionClass,
}
if n.Proxy == nil {
log.Debugw("constructing-new-proxy", log.Fields{
"node-type": reflect.ValueOf(n.Type).Type(),
"parent-node-type": reflect.ValueOf(parentNode.Type).Type(),
"path": path,
"fullPath": fullPath,
})
n.Proxy = NewProxy(r, n, parentNode, path, fullPath, exclusive)
} else {
log.Debugw("node-has-existing-proxy", log.Fields{
"node-type": reflect.ValueOf(n.GetProxy().Node.Type).Type(),
"parent-node-type": reflect.ValueOf(n.GetProxy().ParentNode.Type).Type(),
"path": n.GetProxy().Path,
"fullPath": n.GetProxy().FullPath,
})
if n.GetProxy().Exclusive {
log.Error("node is already owned exclusively")
}
}
return n.Proxy
}
func (n *node) makeEventBus() *EventBus {
if n.EventBus == nil {
n.EventBus = NewEventBus()
}
return n.EventBus
}
func (n *node) SetProxy(proxy *Proxy) {
n.Proxy = proxy
}
func (n *node) GetProxy() *Proxy {
return n.Proxy
}
func (n *node) GetBranch(key string) *Branch {
if n.Branches != nil {
if branch, exists := n.Branches[key]; exists {
return branch
}
}
return nil
}
func (n *node) SetBranch(key string, branch *Branch) {
n.Branches[key] = branch
}
func (n *node) GetRoot() *root {
return n.Root
}
func (n *node) SetRoot(root *root) {
n.Root = root
}