Golang KVWriter.Close方法代碼示例

func (f *Firestorm) Update(doc *document.Document) (err error) {

	// assign this document a number
	doc.Number = atomic.AddUint64(&f.highDocNumber, 1)

	// do analysis before acquiring write lock
	analysisStart := time.Now()
	resultChan := make(chan *index.AnalysisResult)
	aw := index.NewAnalysisWork(f, doc, resultChan)

	// put the work on the queue
	f.analysisQueue.Queue(aw)

	// wait for the result
	result := <-resultChan
	close(resultChan)
	atomic.AddUint64(&f.stats.analysisTime, uint64(time.Since(analysisStart)))

	// start a writer for this update
	indexStart := time.Now()
	var kvwriter store.KVWriter
	kvwriter, err = f.store.Writer()
	if err != nil {
		return
	}
	defer func() {
		if cerr := kvwriter.Close(); err == nil && cerr != nil {
			err = cerr
		}
	}()

	var dictionaryDeltas map[string]int64
	dictionaryDeltas, err = f.batchRows(kvwriter, [][]index.IndexRow{result.Rows}, nil)
	if err != nil {
		_ = kvwriter.Close()
		atomic.AddUint64(&f.stats.errors, 1)
		return
	}

	f.compensator.Mutate([]byte(doc.ID), doc.Number)
	f.lookuper.NotifyBatch([]*InFlightItem{&InFlightItem{[]byte(doc.ID), doc.Number}})
	f.dictUpdater.NotifyBatch(dictionaryDeltas)

	atomic.AddUint64(&f.stats.indexTime, uint64(time.Since(indexStart)))
	return
}

func (f *Firestorm) DeleteInternal(key []byte) (err error) {
	internalRow := NewInternalRow(key, nil)
	var writer store.KVWriter
	writer, err = f.store.Writer()
	if err != nil {
		return
	}
	defer func() {
		if cerr := writer.Close(); err == nil && cerr != nil {
			err = cerr
		}
	}()

	wb := writer.NewBatch()
	wb.Delete(internalRow.Key())

	return writer.ExecuteBatch(wb)
}

func (udc *UpsideDownCouch) DeleteInternal(key []byte) (err error) {
	internalRow := NewInternalRow(key, nil)
	udc.writeMutex.Lock()
	defer udc.writeMutex.Unlock()
	var writer store.KVWriter
	writer, err = udc.store.Writer()
	if err != nil {
		return
	}
	defer func() {
		if cerr := writer.Close(); err == nil && cerr != nil {
			err = cerr
		}
	}()

	batch := writer.NewBatch()
	batch.Delete(internalRow.Key())
	return writer.ExecuteBatch(batch)
}

func (udc *UpsideDownCouch) Batch(batch *index.Batch) (err error) {
	analysisStart := time.Now()

	resultChan := make(chan *index.AnalysisResult, len(batch.IndexOps))

	var numUpdates uint64
	for _, doc := range batch.IndexOps {
		if doc != nil {
			numUpdates++
		}
	}

	var detectedUnsafeMutex sync.RWMutex
	detectedUnsafe := false

	go func() {
		sofar := uint64(0)
		for _, doc := range batch.IndexOps {
			if doc != nil {
				sofar++
				if sofar > numUpdates {
					detectedUnsafeMutex.Lock()
					detectedUnsafe = true
					detectedUnsafeMutex.Unlock()
					return
				}
				aw := index.NewAnalysisWork(udc, doc, resultChan)
				// put the work on the queue
				udc.analysisQueue.Queue(aw)
			}
		}
	}()

	// retrieve back index rows concurrent with analysis
	docBackIndexRowErr := error(nil)
	docBackIndexRowCh := make(chan *docBackIndexRow, len(batch.IndexOps))

	udc.writeMutex.Lock()
	defer udc.writeMutex.Unlock()

	go func() {
		defer close(docBackIndexRowCh)

		// open a reader for backindex lookup
		var kvreader store.KVReader
		kvreader, err = udc.store.Reader()
		if err != nil {
			docBackIndexRowErr = err
			return
		}

		for docID, doc := range batch.IndexOps {
			backIndexRow, err := udc.backIndexRowForDoc(kvreader, docID)
			if err != nil {
				docBackIndexRowErr = err
				return
			}

			docBackIndexRowCh <- &docBackIndexRow{docID, doc, backIndexRow}
		}

		err = kvreader.Close()
		if err != nil {
			docBackIndexRowErr = err
			return
		}
	}()

	// wait for analysis result
	newRowsMap := make(map[string][]index.IndexRow)
	var itemsDeQueued uint64
	for itemsDeQueued < numUpdates {
		result := <-resultChan
		newRowsMap[result.DocID] = result.Rows
		itemsDeQueued++
	}
	close(resultChan)

	atomic.AddUint64(&udc.stats.analysisTime, uint64(time.Since(analysisStart)))

	docsAdded := uint64(0)
	docsDeleted := uint64(0)

	indexStart := time.Now()

	// prepare a list of rows
	var addRowsAll [][]UpsideDownCouchRow
	var updateRowsAll [][]UpsideDownCouchRow
	var deleteRowsAll [][]UpsideDownCouchRow

	// add the internal ops
	var updateRows []UpsideDownCouchRow
	var deleteRows []UpsideDownCouchRow

	for internalKey, internalValue := range batch.InternalOps {
		if internalValue == nil {
			// delete
			deleteInternalRow := NewInternalRow([]byte(internalKey), nil)
			deleteRows = append(deleteRows, deleteInternalRow)
		} else {
//.........這裏部分代碼省略.........

func (udc *UpsideDownCouch) Delete(id string) (err error) {
	indexStart := time.Now()

	udc.writeMutex.Lock()
	defer udc.writeMutex.Unlock()

	// open a reader for backindex lookup
	var kvreader store.KVReader
	kvreader, err = udc.store.Reader()
	if err != nil {
		return
	}

	// first we lookup the backindex row for the doc id if it exists
	// lookup the back index row
	var backIndexRow *BackIndexRow
	backIndexRow, err = udc.backIndexRowForDoc(kvreader, id)
	if err != nil {
		_ = kvreader.Close()
		atomic.AddUint64(&udc.stats.errors, 1)
		return
	}

	err = kvreader.Close()
	if err != nil {
		return
	}

	if backIndexRow == nil {
		atomic.AddUint64(&udc.stats.deletes, 1)
		return
	}

	// start a writer for this delete
	var kvwriter store.KVWriter
	kvwriter, err = udc.store.Writer()
	if err != nil {
		return
	}
	defer func() {
		if cerr := kvwriter.Close(); err == nil && cerr != nil {
			err = cerr
		}
	}()

	var deleteRowsAll [][]UpsideDownCouchRow

	deleteRows := udc.deleteSingle(id, backIndexRow, nil)
	if len(deleteRows) > 0 {
		deleteRowsAll = append(deleteRowsAll, deleteRows)
	}

	err = udc.batchRows(kvwriter, nil, nil, deleteRowsAll)
	if err == nil {
		udc.m.Lock()
		udc.docCount--
		udc.m.Unlock()
	}
	atomic.AddUint64(&udc.stats.indexTime, uint64(time.Since(indexStart)))
	if err == nil {
		atomic.AddUint64(&udc.stats.deletes, 1)
	} else {
		atomic.AddUint64(&udc.stats.errors, 1)
	}
	return
}

func (udc *UpsideDownCouch) Update(doc *document.Document) (err error) {
	// do analysis before acquiring write lock
	analysisStart := time.Now()
	resultChan := make(chan *index.AnalysisResult)
	aw := index.NewAnalysisWork(udc, doc, resultChan)

	// put the work on the queue
	udc.analysisQueue.Queue(aw)

	// wait for the result
	result := <-resultChan
	close(resultChan)
	atomic.AddUint64(&udc.stats.analysisTime, uint64(time.Since(analysisStart)))

	udc.writeMutex.Lock()
	defer udc.writeMutex.Unlock()

	// open a reader for backindex lookup
	var kvreader store.KVReader
	kvreader, err = udc.store.Reader()
	if err != nil {
		return
	}

	// first we lookup the backindex row for the doc id if it exists
	// lookup the back index row
	var backIndexRow *BackIndexRow
	backIndexRow, err = udc.backIndexRowForDoc(kvreader, doc.ID)
	if err != nil {
		_ = kvreader.Close()
		atomic.AddUint64(&udc.stats.errors, 1)
		return
	}

	err = kvreader.Close()
	if err != nil {
		return
	}

	// start a writer for this update
	indexStart := time.Now()
	var kvwriter store.KVWriter
	kvwriter, err = udc.store.Writer()
	if err != nil {
		return
	}
	defer func() {
		if cerr := kvwriter.Close(); err == nil && cerr != nil {
			err = cerr
		}
	}()

	// prepare a list of rows
	var addRowsAll [][]UpsideDownCouchRow
	var updateRowsAll [][]UpsideDownCouchRow
	var deleteRowsAll [][]UpsideDownCouchRow

	addRows, updateRows, deleteRows := udc.mergeOldAndNew(backIndexRow, result.Rows)
	if len(addRows) > 0 {
		addRowsAll = append(addRowsAll, addRows)
	}
	if len(updateRows) > 0 {
		updateRowsAll = append(updateRowsAll, updateRows)
	}
	if len(deleteRows) > 0 {
		deleteRowsAll = append(deleteRowsAll, deleteRows)
	}

	err = udc.batchRows(kvwriter, addRowsAll, updateRowsAll, deleteRowsAll)
	if err == nil && backIndexRow == nil {
		udc.m.Lock()
		udc.docCount++
		udc.m.Unlock()
	}
	atomic.AddUint64(&udc.stats.indexTime, uint64(time.Since(indexStart)))
	if err == nil {
		atomic.AddUint64(&udc.stats.updates, 1)
	} else {
		atomic.AddUint64(&udc.stats.errors, 1)
	}
	return
}

func (udc *UpsideDownCouch) Open() (err error) {
	//acquire the write mutex for the duratin of Open()
	udc.writeMutex.Lock()
	defer udc.writeMutex.Unlock()

	// open the kv store
	storeConstructor := registry.KVStoreConstructorByName(udc.storeName)
	if storeConstructor == nil {
		err = index.ErrorUnknownStorageType
		return
	}

	// now open the store
	udc.store, err = storeConstructor(&mergeOperator, udc.storeConfig)
	if err != nil {
		return
	}

	// start a reader to look at the index
	var kvreader store.KVReader
	kvreader, err = udc.store.Reader()
	if err != nil {
		return
	}

	var value []byte
	value, err = kvreader.Get(VersionKey)
	if err != nil {
		_ = kvreader.Close()
		return
	}

	if value != nil {
		err = udc.loadSchema(kvreader)
		if err != nil {
			_ = kvreader.Close()
			return
		}

		// set doc count
		udc.m.Lock()
		udc.docCount, err = udc.countDocs(kvreader)
		udc.m.Unlock()

		err = kvreader.Close()
	} else {
		// new index, close the reader and open writer to init
		err = kvreader.Close()
		if err != nil {
			return
		}

		var kvwriter store.KVWriter
		kvwriter, err = udc.store.Writer()
		if err != nil {
			return
		}
		defer func() {
			if cerr := kvwriter.Close(); err == nil && cerr != nil {
				err = cerr
			}
		}()

		// init the index
		err = udc.init(kvwriter)
	}

	return
}

//.........這裏部分代碼省略.........
		for _, doc := range batch.IndexOps {
			if doc != nil {
				sofar++
				if sofar > docsUpdated {
					detectedUnsafeMutex.Lock()
					detectedUnsafe = true
					detectedUnsafeMutex.Unlock()
					return
				}
				aw := index.NewAnalysisWork(f, doc, resultChan)
				// put the work on the queue
				f.analysisQueue.Queue(aw)
			}
		}
	}()

	// extra 1 capacity for internal updates.
	collectRows := make([][]index.IndexRow, 0, docsUpdated+1)

	// wait for the result
	var itemsDeQueued uint64
	for itemsDeQueued < docsUpdated {
		result := <-resultChan
		collectRows = append(collectRows, result.Rows)
		itemsDeQueued++
	}
	close(resultChan)

	detectedUnsafeMutex.RLock()
	defer detectedUnsafeMutex.RUnlock()
	if detectedUnsafe {
		return UnsafeBatchUseDetected
	}

	atomic.AddUint64(&f.stats.analysisTime, uint64(time.Since(analysisStart)))

	var deleteKeys [][]byte
	if len(batch.InternalOps) > 0 {
		// add the internal ops
		updateInternalRows := make([]index.IndexRow, 0, len(batch.InternalOps))
		for internalKey, internalValue := range batch.InternalOps {
			if internalValue == nil {
				// delete
				deleteInternalRow := NewInternalRow([]byte(internalKey), nil)
				deleteKeys = append(deleteKeys, deleteInternalRow.Key())
			} else {
				updateInternalRow := NewInternalRow([]byte(internalKey), internalValue)
				updateInternalRows = append(updateInternalRows, updateInternalRow)
			}
		}
		collectRows = append(collectRows, updateInternalRows)
	}

	inflightItems := make([]*InFlightItem, 0, len(batch.IndexOps))
	for docID, doc := range batch.IndexOps {
		if doc != nil {
			inflightItems = append(inflightItems,
				&InFlightItem{[]byte(docID), doc.Number})
		} else {
			inflightItems = append(inflightItems,
				&InFlightItem{[]byte(docID), 0})
		}
	}

	indexStart := time.Now()

	// start a writer for this batch
	var kvwriter store.KVWriter
	kvwriter, err = f.store.Writer()
	if err != nil {
		return
	}

	var dictionaryDeltas map[string]int64
	dictionaryDeltas, err = f.batchRows(kvwriter, collectRows, deleteKeys)
	if err != nil {
		_ = kvwriter.Close()
		atomic.AddUint64(&f.stats.errors, 1)
		return
	}

	f.compensator.MutateBatch(inflightItems, lastDocNumber)

	err = kvwriter.Close()

	f.lookuper.NotifyBatch(inflightItems)
	f.dictUpdater.NotifyBatch(dictionaryDeltas)

	atomic.AddUint64(&f.stats.indexTime, uint64(time.Since(indexStart)))

	if err == nil {
		atomic.AddUint64(&f.stats.updates, docsUpdated)
		atomic.AddUint64(&f.stats.deletes, docsDeleted)
		atomic.AddUint64(&f.stats.batches, 1)
	} else {
		atomic.AddUint64(&f.stats.errors, 1)
	}

	return
}