Merge pull request #226 from google/dvyukov-vendor

vendor: vendor dependencies

1 files changed, 250 insertions, 0 deletions

diff --git a/vendor/cloud.google.com/go/bigtable/reader.go b/vendor/cloud.google.com/go/bigtable/reader.go
new file mode 100644
index 000000000..4af2f7020
--- /dev/null
+++ b/vendor/cloud.google.com/go/bigtable/reader.go
@@ -0,0 +1,250 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+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 bigtable
+
+import (
+	"bytes"
+	"fmt"
+
+	btpb "google.golang.org/genproto/googleapis/bigtable/v2"
+)
+
+// A Row is returned by ReadRows. The map is keyed by column family (the prefix
+// of the column name before the colon). The values are the returned ReadItems
+// for that column family in the order returned by Read.
+type Row map[string][]ReadItem
+
+// Key returns the row's key, or "" if the row is empty.
+func (r Row) Key() string {
+	for _, items := range r {
+		if len(items) > 0 {
+			return items[0].Row
+		}
+	}
+	return ""
+}
+
+// A ReadItem is returned by Read. A ReadItem contains data from a specific row and column.
+type ReadItem struct {
+	Row, Column string
+	Timestamp   Timestamp
+	Value       []byte
+}
+
+// The current state of the read rows state machine.
+type rrState int64
+
+const (
+	newRow rrState = iota
+	rowInProgress
+	cellInProgress
+)
+
+// chunkReader handles cell chunks from the read rows response and combines
+// them into full Rows.
+type chunkReader struct {
+	state   rrState
+	curKey  []byte
+	curFam  string
+	curQual []byte
+	curTS   int64
+	curVal  []byte
+	curRow  Row
+	lastKey string
+}
+
+// newChunkReader returns a new chunkReader for handling read rows responses.
+func newChunkReader() *chunkReader {
+	return &chunkReader{state: newRow}
+}
+
+// Process takes a cell chunk and returns a new Row if the given chunk
+// completes a Row, or nil otherwise.
+func (cr *chunkReader) Process(cc *btpb.ReadRowsResponse_CellChunk) (Row, error) {
+	var row Row
+	switch cr.state {
+	case newRow:
+		if err := cr.validateNewRow(cc); err != nil {
+			return nil, err
+		}
+
+		cr.curRow = make(Row)
+		cr.curKey = cc.RowKey
+		cr.curFam = cc.FamilyName.Value
+		cr.curQual = cc.Qualifier.Value
+		cr.curTS = cc.TimestampMicros
+		row = cr.handleCellValue(cc)
+
+	case rowInProgress:
+		if err := cr.validateRowInProgress(cc); err != nil {
+			return nil, err
+		}
+
+		if cc.GetResetRow() {
+			cr.resetToNewRow()
+			return nil, nil
+		}
+
+		if cc.FamilyName != nil {
+			cr.curFam = cc.FamilyName.Value
+		}
+		if cc.Qualifier != nil {
+			cr.curQual = cc.Qualifier.Value
+		}
+		cr.curTS = cc.TimestampMicros
+		row = cr.handleCellValue(cc)
+
+	case cellInProgress:
+		if err := cr.validateCellInProgress(cc); err != nil {
+			return nil, err
+		}
+		if cc.GetResetRow() {
+			cr.resetToNewRow()
+			return nil, nil
+		}
+		row = cr.handleCellValue(cc)
+	}
+
+	return row, nil
+}
+
+// Close must be called after all cell chunks from the response
+// have been processed. An error will be returned if the reader is
+// in an invalid state, in which case the error should be propagated to the caller.
+func (cr *chunkReader) Close() error {
+	if cr.state != newRow {
+		return fmt.Errorf("invalid state for end of stream %q", cr.state)
+	}
+	return nil
+}
+
+// handleCellValue returns a Row if the cell value includes a commit, otherwise nil.
+func (cr *chunkReader) handleCellValue(cc *btpb.ReadRowsResponse_CellChunk) Row {
+	if cc.ValueSize > 0 {
+		// ValueSize is specified so expect a split value of ValueSize bytes
+		if cr.curVal == nil {
+			cr.curVal = make([]byte, 0, cc.ValueSize)
+		}
+		cr.curVal = append(cr.curVal, cc.Value...)
+		cr.state = cellInProgress
+	} else {
+		// This cell is either the complete value or the last chunk of a split
+		if cr.curVal == nil {
+			cr.curVal = cc.Value
+		} else {
+			cr.curVal = append(cr.curVal, cc.Value...)
+		}
+		cr.finishCell()
+
+		if cc.GetCommitRow() {
+			return cr.commitRow()
+		} else {
+			cr.state = rowInProgress
+		}
+	}
+
+	return nil
+}
+
+func (cr *chunkReader) finishCell() {
+	ri := ReadItem{
+		Row:       string(cr.curKey),
+		Column:    fmt.Sprintf("%s:%s", cr.curFam, cr.curQual),
+		Timestamp: Timestamp(cr.curTS),
+		Value:     cr.curVal,
+	}
+	cr.curRow[cr.curFam] = append(cr.curRow[cr.curFam], ri)
+	cr.curVal = nil
+}
+
+func (cr *chunkReader) commitRow() Row {
+	row := cr.curRow
+	cr.lastKey = cr.curRow.Key()
+	cr.resetToNewRow()
+	return row
+}
+
+func (cr *chunkReader) resetToNewRow() {
+	cr.curKey = nil
+	cr.curFam = ""
+	cr.curQual = nil
+	cr.curVal = nil
+	cr.curRow = nil
+	cr.curTS = 0
+	cr.state = newRow
+}
+
+func (cr *chunkReader) validateNewRow(cc *btpb.ReadRowsResponse_CellChunk) error {
+	if cc.GetResetRow() {
+		return fmt.Errorf("reset_row not allowed between rows")
+	}
+	if cc.RowKey == nil || cc.FamilyName == nil || cc.Qualifier == nil {
+		return fmt.Errorf("missing key field for new row %v", cc)
+	}
+	if cr.lastKey != "" && cr.lastKey >= string(cc.RowKey) {
+		return fmt.Errorf("out of order row key: %q, %q", cr.lastKey, string(cc.RowKey))
+	}
+	return nil
+}
+
+func (cr *chunkReader) validateRowInProgress(cc *btpb.ReadRowsResponse_CellChunk) error {
+	if err := cr.validateRowStatus(cc); err != nil {
+		return err
+	}
+	if cc.RowKey != nil && !bytes.Equal(cc.RowKey, cr.curKey) {
+		return fmt.Errorf("received new row key %q during existing row %q", cc.RowKey, cr.curKey)
+	}
+	if cc.FamilyName != nil && cc.Qualifier == nil {
+		return fmt.Errorf("family name %q specified without a qualifier", cc.FamilyName)
+	}
+	return nil
+}
+
+func (cr *chunkReader) validateCellInProgress(cc *btpb.ReadRowsResponse_CellChunk) error {
+	if err := cr.validateRowStatus(cc); err != nil {
+		return err
+	}
+	if cr.curVal == nil {
+		return fmt.Errorf("no cached cell while CELL_IN_PROGRESS %v", cc)
+	}
+	if cc.GetResetRow() == false && cr.isAnyKeyPresent(cc) {
+		return fmt.Errorf("cell key components found while CELL_IN_PROGRESS %v", cc)
+	}
+	return nil
+}
+
+func (cr *chunkReader) isAnyKeyPresent(cc *btpb.ReadRowsResponse_CellChunk) bool {
+	return cc.RowKey != nil ||
+		cc.FamilyName != nil ||
+		cc.Qualifier != nil ||
+		cc.TimestampMicros != 0
+}
+
+// Validate a RowStatus, commit or reset, if present.
+func (cr *chunkReader) validateRowStatus(cc *btpb.ReadRowsResponse_CellChunk) error {
+	// Resets can't be specified with any other part of a cell
+	if cc.GetResetRow() && (cr.isAnyKeyPresent(cc) ||
+		cc.Value != nil ||
+		cc.ValueSize != 0 ||
+		cc.Labels != nil) {
+		return fmt.Errorf("reset must not be specified with other fields %v", cc)
+	}
+	if cc.GetCommitRow() && cc.ValueSize > 0 {
+		return fmt.Errorf("commit row found in between chunks in a cell")
+	}
+	return nil
+}