Complete context on forwarded local errors

[onechat] / tree.go

diff --git a/tree.go b/tree.go
index af164aed859ac7f64784c60d4c301314aab27b7f..765016eaba3e14c1ebd2dba4b5b30356346418e4 100644 (file)
--- a/tree.go
+++ b/tree.go
@@ -23,76 +23,6 @@ const nodeBytes = 512
 // the node line, the node index, and the node level.
 const treeRecordBytes = 32
 
 // the node line, the node index, and the node level.
 const treeRecordBytes = 32
 

-// openTree opens the tree of the chat in root and indexes its new lines. A chat
-// of total messages cannot have a node that covers a later message.
-func openTree(ctx context.Context, root string, total int, clock func() time.Time) (*Tree, error) {
-       for _, dir := range []string{"tree", "index"} {
-               err := os.MkdirAll(filepath.Join(root, dir), 0o700)
-               if err != nil {
-                       return nil, fmt.Errorf("create %s directory: %w", dir, err)
-               }
-       }
-
-       t := &Tree{
-               clock: clock,
-               journal: Journal{
-                       dir: filepath.Join(root, "tree"),
-               },
-               dir:    filepath.Join(root, "index"),
-               levels: make(map[int]*Records),
-       }
-
-       err := t.open(ctx, total)
-       if err != nil {
-               return nil, errors.Join(fmt.Errorf("index tree: %w", err), t.Close())
-       }
-
-       return t, nil
-}
-
-// leafSource returns the text that the leaf of message holds or summarizes.
-func leafSource(message Message) string {
-       return message.Kind + ": " + message.Text
-}
-
-// freeLeaf returns the leaf of message when its source fits in a node. Such a
-// leaf holds the source word for word and needs no model call.
-func freeLeaf(message Message) (Node, bool) {
-       text := leafSource(message)
-       if len(text) > nodeBytes {
-               return Node{}, false
-       }
-
-       return Node{
-               Level: 0,
-               Index: message.ID,
-               Text:  text,
-               Size:  len(text),
-       }, true
-}
-
-// freeMerge returns the parent of two sibling nodes when both texts, joined by
-// a newline, fit in a node. Such a parent needs no model call.
-func freeMerge(left, right Node) (Node, bool) {
-       if left.Size+1+right.Size > nodeBytes {
-               return Node{}, false
-       }
-
-       text := left.Text + "\n" + right.Text
-
-       return Node{
-               Level: left.Level + 1,
-               Index: left.Index / 2,
-               Text:  text,
-               Size:  len(text),
-       }, true
-}
-
-// nodeEnd returns the ID after the last message of node (l, i).
-func nodeEnd(level, index int) int {
-       return (index + 1) << level
-}
-

 // Tree holds the built nodes of one chat. It writes one JSON line for each node
 // to tree/YYYY-MM-DD.jsonl, named for the local day of the build. Each node is
 // built once and never again. A node of a higher level is built only after both
 // Tree holds the built nodes of one chat. It writes one JSON line for each node
 // to tree/YYYY-MM-DD.jsonl, named for the local day of the build. Each node is
 // built once and never again. A node of a higher level is built only after both


@@ -114,119 +44,68 @@ type Tree struct {
        failure error
 }
 
        failure error
 }
 

-// Close closes the files of the tree.
-func (t *Tree) Close() error {
-       err := t.journal.Close()
-       if t.order != nil {
-               err = errors.Join(err, t.order.Close())
-               t.order = nil
-       }
-
-       for level, index := range t.levels {
-               err = errors.Join(err, index.Close())
-               delete(t.levels, level)
-       }
-
-       return err
-}
-
-// Add writes a new node to the tree.
-func (t *Tree) Add(node Node) error {
-       if t.failure != nil {
-               return fmt.Errorf("tree needs a reopen after a failed write: %w", t.failure)
-       }
-
-       err := t.check(node)
-       if err != nil {
-               return err
-       }
-
-       line, err := json.Marshal(node)
-       if err != nil {
-               return fmt.Errorf("encode node: %w", err)
-       }
-
-       place, err := t.journal.Write(t.clock().Format(time.DateOnly), append(line, '\n'))
-       if err == nil {
-               err = t.addIndex(NodeKey{node.Level, node.Index}, place)
-       }
-
-       if err != nil {
-               t.failure = err
-               return fmt.Errorf("write node (%d, %d): %w", node.Level, node.Index, err)
-       }
-
-       return nil
+// Node is one line of the summary tree. Node (l, i) covers the 2^l messages
+// from i*2^l on. A node of level 0 holds one message. A node of a higher level
+// merges its two children, (l-1, 2i) and (l-1, 2i+1). Size is the UTF-8 byte
+// length of Text.
+type Node struct {
+       Level int    `json:"l"`
+       Index int    `json:"i"`
+       Text  string `json:"text"`
+       Size  int    `json:"size"`

 }
 
 }
 

-// Built tells if the node (l, i) is built.
-func (t *Tree) Built(level, index int) (bool, error) {
-       _, built, err := t.place(level, index)
-       return built, err
+// NodeKey names the node (l, i).
+type NodeKey struct {
+       level int
+       index int

 }
 
 }
 

-// Node reads the node (l, i) if it is built.
-func (t *Tree) Node(level, index int) (Node, bool, error) {
-       place, built, err := t.place(level, index)
-       if err != nil || !built {
-               return Node{}, false, err
+// openTree opens the tree of the chat in root and indexes its new lines. A chat
+// of total messages cannot have a node that covers a later message.
+func openTree(ctx context.Context, root string, total int, clock func() time.Time) (*Tree, error) {
+       for _, dir := range []string{"tree", "index"} {
+               err := os.MkdirAll(filepath.Join(root, dir), 0o700)
+               if err != nil {
+                       return nil, fmt.Errorf("create %s directory: %w", dir, err)
+               }

        }
 
        }
 

-       line, err := t.journal.Read(place)
-       if err != nil {
-               return Node{}, false, fmt.Errorf("read node (%d, %d): %w", level, index, err)
+       t := &Tree{
+               clock: clock,
+               journal: Journal{
+                       dir: filepath.Join(root, "tree"),
+               },
+               dir:    filepath.Join(root, "index"),
+               levels: make(map[int]*Records),

        }
 
        }
 

-       var node Node
-       err = json.Unmarshal(line, &node)
+       err := t.open(ctx, total)

        if err != nil {
        if err != nil {

-               return Node{}, false, fmt.Errorf("decode node (%d, %d): %w", level, index, err)
-       }
-
-       if node.Level != level || node.Index != index {
-               return Node{}, false, fmt.Errorf("index of node (%d, %d) points to node (%d, %d)", level, index, node.Level, node.Index)
-       }
-
-       return node, true, nil
-}
-
-// Keys returns the keys of the built nodes, ordered by level and then by index.
-func (t *Tree) Keys() ([]NodeKey, error) {
-       keys := make([]NodeKey, 0, t.order.count)
-       for n := range t.order.count {
-               record, _, err := t.order.Read(n)
-               if err != nil {
-                       return nil, err
-               }
-
-               key, _ := treeDecodeRecord(record)
-               keys = append(keys, key)
+               return nil, errors.Join(fmt.Errorf("index tree: %w", err), t.Close())

        }
 
        }
 

-       slices.SortFunc(keys, func(a, b NodeKey) int {
-               return cmp.Or(cmp.Compare(a.level, b.level), cmp.Compare(a.index, b.index))
-       })
-
-       return keys, nil
+       return t, nil

 }
 
 func (t *Tree) open(ctx context.Context, total int) error {
        var err error
 }
 
 func (t *Tree) open(ctx context.Context, total int) error {
        var err error

+

        t.order, err = openRecords(filepath.Join(t.dir, "tree.idx"), treeRecordBytes)
        if err != nil {
        t.order, err = openRecords(filepath.Join(t.dir, "tree.idx"), treeRecordBytes)
        if err != nil {

-               return err
+               return fmt.Errorf("open node order index: %w", err)

        }
 
        start := Position{}
        if t.order.count == 0 {
                err = t.removeLevels()
                if err != nil {
        }
 
        start := Position{}
        if t.order.count == 0 {
                err = t.removeLevels()
                if err != nil {

-                       return err
+                       return fmt.Errorf("remove empty level indexes: %w", err)

                }
        } else {
                record, _, err := t.order.Read(t.order.count - 1)
                if err != nil {
                }
        } else {
                record, _, err := t.order.Read(t.order.count - 1)
                if err != nil {

-                       return err
+                       return fmt.Errorf("read last node order: %w", err)

                }
 
                // A crash can stop an add between the two index writes, so the
                }
 
                // A crash can stop an add between the two index writes, so the


@@ -234,7 +113,7 @@ func (t *Tree) open(ctx context.Context, total int) error {
                node, last := treeDecodeRecord(record)
                err = t.writeLevel(node, last)
                if err != nil {
                node, last := treeDecodeRecord(record)
                err = t.writeLevel(node, last)
                if err != nil {

-                       return err
+                       return fmt.Errorf("restore last node level: %w", err)

                }
 
                start = Position{
                }
 
                start = Position{


@@ -243,24 +122,88 @@ func (t *Tree) open(ctx context.Context, total int) error {
                }
        }
 
                }
        }
 

-       return t.journal.Scan(ctx, start, func(line []byte, place Position) error {
+       err = t.journal.Scan(ctx, start, func(line []byte, place Position) error {

                var node Node
                var node Node

+

                err := json.Unmarshal(line, &node)
                if err != nil {
                err := json.Unmarshal(line, &node)
                if err != nil {

-                       return err
+                       return fmt.Errorf("decode tree node: %w", err)

                }
 
                err = t.check(node)
                if err != nil {
                }
 
                err = t.check(node)
                if err != nil {

-                       return err
+                       return fmt.Errorf("validate scanned node: %w", err)

                }
 
                if nodeEnd(node.Level, node.Index) > total {
                        return fmt.Errorf("node (%d, %d) covers messages after the log", node.Level, node.Index)
                }
 
                }
 
                if nodeEnd(node.Level, node.Index) > total {
                        return fmt.Errorf("node (%d, %d) covers messages after the log", node.Level, node.Index)
                }
 

-               return t.addIndex(NodeKey{node.Level, node.Index}, place)
+               err = t.addIndex(NodeKey{node.Level, node.Index}, place)
+               if err != nil {
+                       return fmt.Errorf("index scanned node: %w", err)
+               }
+
+               return nil

        })
        })

+       if err != nil {
+               return fmt.Errorf("scan node journal: %w", err)
+       }
+
+       return nil
+}
+
+// Close closes the files of the tree.
+func (t *Tree) Close() error {
+       err := t.journal.Close()
+       if t.order != nil {
+               err = errors.Join(err, t.order.Close())
+               t.order = nil
+       }
+
+       for level, index := range t.levels {
+               err = errors.Join(err, index.Close())
+
+               delete(t.levels, level)
+       }
+
+       return err
+}
+
+// removeLevels removes the level indexes, which are not valid without the order
+// index.
+func (t *Tree) removeLevels() error {
+       paths, err := filepath.Glob(filepath.Join(t.dir, "tree-*.idx"))
+       if err != nil {
+               return fmt.Errorf("list level indexes: %w", err)
+       }
+
+       for _, path := range paths {
+               err = os.Remove(path)
+               if err != nil {
+                       return fmt.Errorf("remove level index: %w", err)
+               }
+       }
+
+       return nil
+}
+
+// writeLevel writes the position of node to its level index.
+func (t *Tree) writeLevel(node NodeKey, place Position) error {
+       level, err := t.level(node.level)
+       if err != nil {
+               return fmt.Errorf("open node level index: %w", err)
+       }
+
+       record := make([]byte, positionBytes)
+       encodePosition(record, place)
+
+       err = level.Write(node.index, record)
+       if err != nil {
+               return fmt.Errorf("write node level record: %w", err)
+       }
+
+       return nil

 }
 
 // check makes sure that node is valid and can join the tree now.
 }
 
 // check makes sure that node is valid and can join the tree now.


@@ -275,7 +218,7 @@ func (t *Tree) check(node Node) error {
 
        built, err := t.Built(node.Level, node.Index)
        if err != nil {
 
        built, err := t.Built(node.Level, node.Index)
        if err != nil {

-               return err
+               return fmt.Errorf("check target node: %w", err)

        }
 
        if built {
        }
 
        if built {


@@ -289,7 +232,7 @@ func (t *Tree) check(node Node) error {
        for _, index := range []int{2 * node.Index, 2*node.Index + 1} {
                built, err = t.Built(node.Level-1, index)
                if err != nil {
        for _, index := range []int{2 * node.Index, 2*node.Index + 1} {
                built, err = t.Built(node.Level-1, index)
                if err != nil {

-                       return err
+                       return fmt.Errorf("check child node: %w", err)

                }
 
                if !built {
                }
 
                if !built {


@@ -309,10 +252,38 @@ func (t *Tree) addIndex(node NodeKey, place Position) error {
 
        err := t.order.Append(record)
        if err != nil {
 
        err := t.order.Append(record)
        if err != nil {

-               return err
+               return fmt.Errorf("append node order: %w", err)
+       }
+
+       err = t.writeLevel(node, place)
+       if err != nil {
+               return fmt.Errorf("write indexed node level: %w", err)

        }
 
        }
 

-       return t.writeLevel(node, place)
+       return nil
+}
+
+// level returns the index of level, and opens it at first use.
+func (t *Tree) level(level int) (*Records, error) {
+       index, open := t.levels[level]
+       if open {
+               return index, nil
+       }
+
+       index, err := openRecords(filepath.Join(t.dir, fmt.Sprintf("tree-%d.idx", level)), positionBytes)
+       if err != nil {
+               return nil, err
+       }
+
+       t.levels[level] = index
+
+       return index, nil
+}
+
+// Built tells if the node (l, i) is built.
+func (t *Tree) Built(level, index int) (bool, error) {
+       _, built, err := t.place(level, index)
+       return built, err

 }
 
 // place returns the position of the node (l, i) if it is built.
 }
 
 // place returns the position of the node (l, i) if it is built.


@@ -323,12 +294,16 @@ func (t *Tree) place(level, index int) (Position, bool, error) {
 
        records, err := t.level(level)
        if err != nil {
 
        records, err := t.level(level)
        if err != nil {

-               return Position{}, false, err
+               return Position{}, false, fmt.Errorf("open node level index: %w", err)

        }
 
        record, found, err := records.Read(index)
        if err != nil || !found {
        }
 
        record, found, err := records.Read(index)
        if err != nil || !found {

-               return Position{}, false, err
+               if err != nil {
+                       return Position{}, false, fmt.Errorf("read node level record: %w", err)
+               }
+
+               return Position{}, false, nil

        }
 
        place := decodePosition(record)
        }
 
        place := decodePosition(record)


@@ -336,52 +311,83 @@ func (t *Tree) place(level, index int) (Position, bool, error) {
        return place, place.length > 0, nil
 }
 
        return place, place.length > 0, nil
 }
 

-// removeLevels removes the level indexes, which are not valid without the order
-// index.
-func (t *Tree) removeLevels() error {
-       paths, err := filepath.Glob(filepath.Join(t.dir, "tree-*.idx"))
+// Add writes a new node to the tree.
+func (t *Tree) Add(node Node) error {
+       if t.failure != nil {
+               return fmt.Errorf("tree needs a reopen after a failed write: %w", t.failure)
+       }
+
+       err := t.check(node)

        if err != nil {
        if err != nil {

-               return fmt.Errorf("list level indexes: %w", err)
+               return fmt.Errorf("validate node: %w", err)

        }
 
        }
 

-       for _, path := range paths {
-               err = os.Remove(path)
-               if err != nil {
-                       return fmt.Errorf("remove level index: %w", err)
-               }
+       line, err := json.Marshal(node)
+       if err != nil {
+               return fmt.Errorf("encode node: %w", err)
+       }
+
+       place, err := t.journal.Write(t.clock().Format(time.DateOnly), append(line, '\n'))
+       if err == nil {
+               err = t.addIndex(NodeKey{node.Level, node.Index}, place)
+       }
+
+       if err != nil {
+               t.failure = err
+               return fmt.Errorf("write node (%d, %d): %w", node.Level, node.Index, err)

        }
 
        return nil
 }
 
        }
 
        return nil
 }
 

-// writeLevel writes the position of node to its level index.
-func (t *Tree) writeLevel(node NodeKey, place Position) error {
-       level, err := t.level(node.level)
+// Node reads the node (l, i) if it is built.
+func (t *Tree) Node(level, index int) (Node, bool, error) {
+       place, built, err := t.place(level, index)
+       if err != nil || !built {
+               if err != nil {
+                       return Node{}, false, fmt.Errorf("find node position: %w", err)
+               }
+
+               return Node{}, false, nil
+       }
+
+       line, err := t.journal.Read(place)

        if err != nil {
        if err != nil {

-               return err
+               return Node{}, false, fmt.Errorf("read node (%d, %d): %w", level, index, err)

        }
 
        }
 

-       record := make([]byte, positionBytes)
-       encodePosition(record, place)
+       var node Node

 
 

-       return level.Write(node.index, record)
-}
+       err = json.Unmarshal(line, &node)
+       if err != nil {
+               return Node{}, false, fmt.Errorf("decode node (%d, %d): %w", level, index, err)
+       }

 
 

-// level returns the index of level, and opens it at first use.
-func (t *Tree) level(level int) (*Records, error) {
-       index, open := t.levels[level]
-       if open {
-               return index, nil
+       if node.Level != level || node.Index != index {
+               return Node{}, false, fmt.Errorf("index of node (%d, %d) points to node (%d, %d)", level, index, node.Level, node.Index)

        }
 
        }
 

-       index, err := openRecords(filepath.Join(t.dir, fmt.Sprintf("tree-%d.idx", level)), positionBytes)
-       if err != nil {
-               return nil, err
+       return node, true, nil
+}
+
+// Keys returns the keys of the built nodes, ordered by level and then by index.
+func (t *Tree) Keys() ([]NodeKey, error) {
+       keys := make([]NodeKey, 0, t.order.count)
+       for n := range t.order.count {
+               record, _, err := t.order.Read(n)
+               if err != nil {
+                       return nil, err
+               }
+
+               key, _ := treeDecodeRecord(record)
+               keys = append(keys, key)

        }
 
        }
 

-       t.levels[level] = index
+       slices.SortFunc(keys, func(a, b NodeKey) int {
+               return cmp.Or(cmp.Compare(a.level, b.level), cmp.Compare(a.index, b.index))
+       })

 
 

-       return index, nil
+       return keys, nil

 }
 
 // Count returns the number of built nodes.
 }
 
 // Count returns the number of built nodes.


@@ -389,23 +395,6 @@ func (t *Tree) Count() int {
        return t.order.count
 }
 
        return t.order.count
 }
 

-// Node is one line of the summary tree. Node (l, i) covers the 2^l messages
-// from i*2^l on. A node of level 0 holds one message. A node of a higher level
-// merges its two children, (l-1, 2i) and (l-1, 2i+1). Size is the UTF-8 byte
-// length of Text.
-type Node struct {
-       Level int    `json:"l"`
-       Index int    `json:"i"`
-       Text  string `json:"text"`
-       Size  int    `json:"size"`
-}
-
-// NodeKey names the node (l, i).
-type NodeKey struct {
-       level int
-       index int
-}
-

 // treeDecodeRecord reads the key and the position of a record of
 // index/tree.idx.
 func treeDecodeRecord(record []byte) (NodeKey, Position) {
 // treeDecodeRecord reads the key and the position of a record of
 // index/tree.idx.
 func treeDecodeRecord(record []byte) (NodeKey, Position) {


@@ -416,3 +405,46 @@ func treeDecodeRecord(record []byte) (NodeKey, Position) {
 
        return key, decodePosition(record)
 }
 
        return key, decodePosition(record)
 }

+
+// nodeEnd returns the ID after the last message of node (l, i).
+func nodeEnd(level, index int) int {
+       return (index + 1) << level
+}
+
+// freeLeaf returns a text-only leaf when its source fits in a node. Images need
+// a model description even when their text fits.
+func freeLeaf(message Message) (Node, bool) {
+       text := leafSource(message)
+       if len(text) > nodeBytes || len(imageFiles(message.Text)) > 0 {
+               return Node{}, false
+       }
+
+       return Node{
+               Level: 0,
+               Index: message.ID,
+               Text:  text,
+               Size:  len(text),
+       }, true
+}
+
+// leafSource returns the text that the leaf of message holds or summarizes.
+func leafSource(message Message) string {
+       return message.Kind + ": " + message.Text
+}
+
+// freeMerge returns the parent of two sibling nodes when both texts, joined by
+// a newline, fit in a node. Such a parent needs no model call.
+func freeMerge(left, right Node) (Node, bool) {
+       if left.Size+1+right.Size > nodeBytes {
+               return Node{}, false
+       }
+
+       text := left.Text + "\n" + right.Text
+
+       return Node{
+               Level: left.Level + 1,
+               Index: left.Index / 2,
+               Text:  text,
+               Size:  len(text),
+       }, true
+}