| package model |
| |
| import ( |
| "fmt" |
| "github.com/golang/protobuf/proto" |
| "reflect" |
| "strings" |
| ) |
| |
| const ( |
| NONE string = "none" |
| ) |
| |
| type Node struct { |
| root *Root |
| Type interface{} |
| Branches map[string]*Branch |
| Tags map[string]*Revision |
| Proxy *Proxy |
| EventBus *EventBus |
| AutoPrune bool |
| } |
| |
| func NewNode(root *Root, initialData interface{}, autoPrune bool, txid string) *Node { |
| cn := &Node{} |
| |
| cn.root = root |
| cn.Branches = make(map[string]*Branch) |
| cn.Tags = make(map[string]*Revision) |
| cn.Proxy = nil |
| cn.EventBus = nil |
| cn.AutoPrune = autoPrune |
| |
| if IsProtoMessage(initialData) { |
| cn.Type = reflect.ValueOf(initialData).Interface() |
| dataCopy := proto.Clone(initialData.(proto.Message)) |
| cn.initialize(dataCopy, txid) |
| } else if reflect.ValueOf(initialData).IsValid() { |
| cn.Type = reflect.ValueOf(initialData).Interface() |
| } else { |
| // not implemented error |
| fmt.Errorf("cannot process initial data - %+v", initialData) |
| } |
| |
| return cn |
| } |
| |
| func (cn *Node) makeNode(data interface{}, txid string) *Node { |
| return NewNode(cn.root, data, true, txid) |
| } |
| |
| func (cn *Node) makeRevision(branch *Branch, data interface{}, children map[string][]*Revision) *Revision { |
| return cn.root.makeRevision(branch, data, children) |
| } |
| |
| func (cn *Node) makeLatest(branch *Branch, revision *Revision, changeAnnouncement map[string]interface{}) { |
| if _, ok := branch.revisions[revision.Hash]; !ok { |
| branch.revisions[revision.Hash] = revision |
| } |
| |
| if branch.Latest == nil || revision.Hash != branch.Latest.Hash { |
| branch.Latest = revision |
| } |
| |
| if changeAnnouncement != nil && branch.Txid == "" { |
| if cn.Proxy != nil { |
| for changeType, data := range changeAnnouncement { |
| // TODO: Invoke callback |
| fmt.Printf("invoking callback - changeType: %+v, data:%+v\n", changeType, data) |
| } |
| } |
| |
| for changeType, data := range changeAnnouncement { |
| // TODO: send notifications |
| fmt.Printf("sending notification - changeType: %+v, data:%+v\n", changeType, data) |
| } |
| } |
| } |
| |
| func (cn *Node) Latest() *Revision { |
| if branch, exists := cn.Branches[NONE]; exists { |
| return branch.Latest |
| } |
| return nil |
| } |
| |
| func (cn *Node) GetHash(hash string) *Revision { |
| return cn.Branches[NONE].revisions[hash] |
| } |
| |
| func (cn *Node) initialize(data interface{}, txid string) { |
| var children map[string][]*Revision |
| children = make(map[string][]*Revision) |
| for fieldName, field := range ChildrenFields(cn.Type) { |
| fieldValue := GetAttributeValue(data, fieldName, 0) |
| |
| if fieldValue.IsValid() { |
| if field.IsContainer { |
| if field.Key != "" { |
| var keysSeen []string |
| |
| for i := 0; i < fieldValue.Len(); i++ { |
| v := fieldValue.Index(i) |
| rev := cn.makeNode(v.Interface(), txid).Latest() |
| key := GetAttributeValue(v.Interface(), field.Key, 0) |
| for _, k := range keysSeen { |
| if k == key.String() { |
| fmt.Errorf("duplicate key - %s", k) |
| } |
| } |
| children[fieldName] = append(children[fieldName], rev) |
| keysSeen = append(keysSeen, key.String()) |
| } |
| |
| } else { |
| for i := 0; i < fieldValue.Len(); i++ { |
| v := fieldValue.Index(i) |
| children[fieldName] = append(children[fieldName], cn.makeNode(v.Interface(), txid).Latest()) |
| } |
| } |
| } else { |
| children[fieldName] = append(children[fieldName], cn.makeNode(fieldValue.Interface(), txid).Latest()) |
| } |
| } else { |
| fmt.Errorf("field is invalid - %+v", fieldValue) |
| } |
| } |
| // FIXME: ClearField??? No such method in go protos. Reset? |
| //data.ClearField(field_name) |
| branch := NewBranch(cn, "", nil, cn.AutoPrune) |
| rev := cn.makeRevision(branch, data, children) |
| cn.makeLatest(branch, rev, nil) |
| cn.Branches[txid] = branch |
| } |
| |
| func (cn *Node) makeTxBranch(txid string) *Branch { |
| branchPoint := cn.Branches[NONE].Latest |
| branch := NewBranch(cn, txid, branchPoint, true) |
| cn.Branches[txid] = branch |
| return branch |
| } |
| |
| func (cn *Node) deleteTxBranch(txid string) { |
| delete(cn.Branches, txid) |
| } |
| |
| type t_makeBranch func(*Node) *Branch |
| |
| // |
| // Get operation |
| // |
| func (cn *Node) Get(path string, hash string, depth int, deep bool, txid string) interface{} { |
| if deep { |
| depth = -1 |
| } |
| |
| for strings.HasPrefix(path, "/") { |
| path = path[1:] |
| } |
| |
| var branch *Branch |
| var rev *Revision |
| |
| // FIXME: should empty txid be cleaned up? |
| if branch = cn.Branches[txid]; txid == "" || branch == nil { |
| branch = cn.Branches[NONE] |
| } |
| |
| if hash != "" { |
| rev = branch.revisions[hash] |
| } else { |
| rev = branch.Latest |
| } |
| |
| return cn.get(rev, path, depth) |
| } |
| |
| func (cn *Node) findRevByKey(revs []*Revision, keyName string, value string) (int, *Revision) { |
| for i, rev := range revs { |
| dataValue := reflect.ValueOf(rev.Config.Data) |
| dataStruct := GetAttributeStructure(rev.Config.Data, keyName, 0) |
| |
| fieldValue := dataValue.Elem().FieldByName(dataStruct.Name) |
| |
| if fieldValue.Interface().(string) == value { |
| return i, rev |
| } |
| } |
| |
| fmt.Errorf("key %s=%s not found", keyName, value) |
| |
| return -1, nil |
| } |
| |
| func (cn *Node) get(rev *Revision, path string, depth int) interface{} { |
| if path == "" { |
| return cn.doGet(rev, depth) |
| } |
| |
| partition := strings.SplitN(path, "/", 2) |
| name := partition[0] |
| path = partition[1] |
| |
| field := ChildrenFields(cn.Type)[name] |
| |
| if field.IsContainer { |
| if field.Key != "" { |
| children := rev.Children[name] |
| if path != "" { |
| partition = strings.SplitN(path, "/", 2) |
| key := partition[0] |
| path = "" |
| key = field.KeyFromStr(key).(string) |
| _, childRev := cn.findRevByKey(children, field.Key, key) |
| childNode := childRev.getNode() |
| return childNode.get(childRev, path, depth) |
| } else { |
| var response []interface{} |
| for _, childRev := range children { |
| childNode := childRev.getNode() |
| value := childNode.doGet(childRev, depth) |
| response = append(response, value) |
| } |
| return response |
| } |
| } else { |
| childRev := rev.Children[name][0] |
| childNode := childRev.getNode() |
| return childNode.get(childRev, path, depth) |
| } |
| } |
| return nil |
| } |
| |
| func (cn *Node) doGet(rev *Revision, depth int) interface{} { |
| msg := rev.Get(depth) |
| |
| if cn.Proxy != nil { |
| // TODO: invoke GET callback |
| fmt.Println("invoking proxy GET Callbacks") |
| } |
| return msg |
| } |
| |
| // |
| // Update operation |
| // |
| func (n *Node) Update(path string, data interface{}, strict bool, txid string, makeBranch t_makeBranch) *Revision { |
| // FIXME: is this required ... a bit overkill to take out a "/" |
| for strings.HasPrefix(path, "/") { |
| path = path[1:] |
| } |
| |
| var branch *Branch |
| var ok bool |
| if branch, ok = n.Branches[txid]; !ok { |
| branch = makeBranch(n) |
| } |
| |
| if path == "" { |
| return n.doUpdate(branch, data, strict) |
| } |
| return &Revision{} |
| } |
| |
| func (n *Node) doUpdate(branch *Branch, data interface{}, strict bool) *Revision { |
| if reflect.TypeOf(data) != n.Type { |
| // TODO raise error |
| fmt.Errorf("data does not match type: %+v", n.Type) |
| } |
| |
| // TODO: noChildren? |
| |
| if n.Proxy != nil { |
| // TODO: n.proxy.InvokeCallbacks(CallbackType.PRE_UPDATE, data) |
| fmt.Println("invoking proxy PRE_UPDATE Callbacks") |
| } |
| if branch.Latest.getData() != data { |
| if strict { |
| // TODO: checkAccessViolations(data, branch.GetLatest.data) |
| fmt.Println("checking access violations") |
| } |
| rev := branch.Latest.UpdateData(data, branch) |
| n.makeLatest(branch, rev, nil) // TODO -> changeAnnouncement needs to be a tuple (CallbackType.POST_UPDATE, rev.data) |
| return rev |
| } else { |
| return branch.Latest |
| } |
| } |
| |
| // TODO: the python implementation has a method to check if the data has no children |
| //func (n *SomeNode) noChildren(data interface{}) bool { |
| // for fieldName, field := range ChildrenFields(n.Type) { |
| // fieldValue := GetAttributeValue(data, fieldName) |
| // |
| // if fieldValue.IsValid() { |
| // if field.IsContainer { |
| // if len(fieldValue) > 0 { |
| // |
| // } |
| // } else { |
| // |
| // } |
| // |
| // } |
| // } |
| //} |
| |
| // |
| // Add operation |
| // |
| func (n *Node) Add(path string, data interface{}, txid string, makeBranch t_makeBranch) *Revision { |
| for strings.HasPrefix(path, "/") { |
| path = path[1:] |
| } |
| if path == "" { |
| // TODO raise error |
| fmt.Errorf("cannot add for non-container mode\n") |
| } |
| |
| var branch *Branch |
| var ok bool |
| if branch, ok = n.Branches[txid]; !ok { |
| branch = makeBranch(n) |
| } |
| |
| rev := branch.Latest |
| |
| partition := strings.SplitN(path, "/", 2) |
| name := partition[0] |
| path = partition[1] |
| |
| field := ChildrenFields(n.Type)[name] |
| var children []*Revision |
| |
| if field.IsContainer { |
| if path == "" { |
| if field.Key != "" { |
| if n.Proxy != nil { |
| // TODO -> n.proxy.InvokeCallbacks(PRE_ADD, data) |
| fmt.Println("invoking proxy PRE_ADD Callbacks") |
| } |
| |
| copy(children, rev.Children[name]) |
| key := GetAttributeValue(data, field.Key, 0) |
| if _, rev := n.findRevByKey(children, field.Key, key.String()); rev != nil { |
| // TODO raise error |
| fmt.Errorf("duplicate key found: %s", key.String()) |
| } |
| |
| childRev := n.makeNode(data, "").Latest() |
| children = append(children, childRev) |
| rev := rev.UpdateChildren(name, children, branch) |
| n.makeLatest(branch, rev, nil) // TODO -> changeAnnouncement needs to be a tuple (CallbackType.POST_ADD, rev.data) |
| return rev |
| } else { |
| fmt.Errorf("cannot add to non-keyed container\n") |
| } |
| } else if field.Key != "" { |
| partition := strings.SplitN(path, "/", 2) |
| key := partition[0] |
| path = partition[1] |
| key = field.KeyFromStr(key).(string) |
| copy(children, rev.Children[name]) |
| idx, childRev := n.findRevByKey(children, field.Key, key) |
| childNode := childRev.getNode() |
| newChildRev := childNode.Add(path, data, txid, makeBranch) |
| children[idx] = newChildRev |
| rev := rev.UpdateChildren(name, children, branch) |
| n.makeLatest(branch, rev, nil) |
| return rev |
| } else { |
| fmt.Errorf("cannot add to non-keyed container\n") |
| } |
| } else { |
| fmt.Errorf("cannot add to non-container field\n") |
| } |
| return nil |
| } |
| |
| // |
| // Remove operation |
| // |
| func (n *Node) Remove(path string, txid string, makeBranch t_makeBranch) *Revision { |
| for strings.HasPrefix(path, "/") { |
| path = path[1:] |
| } |
| if path == "" { |
| // TODO raise error |
| fmt.Errorf("cannot remove for non-container mode\n") |
| } |
| var branch *Branch |
| var ok bool |
| if branch, ok = n.Branches[txid]; !ok { |
| branch = makeBranch(n) |
| } |
| |
| rev := branch.Latest |
| |
| partition := strings.SplitN(path, "/", 2) |
| name := partition[0] |
| path = partition[1] |
| |
| field := ChildrenFields(n.Type)[name] |
| var children []*Revision |
| post_anno := make(map[string]interface{}) |
| |
| if field.IsContainer { |
| if path == "" { |
| fmt.Errorf("cannot remove without a key\n") |
| } else if field.Key != "" { |
| partition := strings.SplitN(path, "/", 2) |
| key := partition[0] |
| path = partition[1] |
| key = field.KeyFromStr(key).(string) |
| if path != "" { |
| copy(children, rev.Children[name]) |
| idx, childRev := n.findRevByKey(children, field.Key, key) |
| childNode := childRev.getNode() |
| newChildRev := childNode.Remove(path, txid, makeBranch) |
| children[idx] = newChildRev |
| rev := rev.UpdateChildren(name, children, branch) |
| n.makeLatest(branch, rev, nil) |
| return rev |
| } else { |
| copy(children, rev.Children[name]) |
| idx, childRev := n.findRevByKey(children, field.Key, key) |
| if n.Proxy != nil { |
| data := childRev.getData() |
| fmt.Println("invoking proxy PRE_REMOVE Callbacks") |
| fmt.Printf("setting POST_REMOVE Callbacks : %+v\n", data) |
| } else { |
| fmt.Println("setting POST_REMOVE Callbacks") |
| } |
| children = append(children[:idx], children[idx+1:]...) |
| rev := rev.UpdateChildren(name, children, branch) |
| n.makeLatest(branch, rev, post_anno) |
| return rev |
| } |
| } else { |
| fmt.Errorf("cannot add to non-keyed container\n") |
| } |
| } else { |
| fmt.Errorf("cannot add to non-container field\n") |
| } |
| |
| return nil |
| } |
| |
| func (n *Node) LoadLatest(kvStore *Backend, hash string) { |
| branch := NewBranch(n, "", nil, n.AutoPrune) |
| pr := &PersistedRevision{} |
| rev := pr.load(branch, kvStore, n.Type, hash) |
| n.makeLatest(branch, rev.Revision, nil) |
| n.Branches[NONE] = branch |
| } |