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authorBen Johnson <benbjohnson@yahoo.com>2016-01-02 22:34:41 -0700
committerBen Johnson <benbjohnson@yahoo.com>2016-01-02 22:34:41 -0700
commit34a0fa5307f7562980fb8e7ff4723f7987edf49b (patch)
tree26a01c0d5a3da53f45c7f54062c3af11479c4a2f /batch.go
parentMerge pull request #474 from elithrar/patch-1 (diff)
parenttest suite refactoring (diff)
downloaddedo-34a0fa5307f7562980fb8e7ff4723f7987edf49b.tar.gz
dedo-34a0fa5307f7562980fb8e7ff4723f7987edf49b.tar.xz
Merge pull request #477 from benbjohnson/testing
Test suite refactoring
Diffstat (limited to 'batch.go')
-rw-r--r--batch.go138
1 files changed, 0 insertions, 138 deletions
diff --git a/batch.go b/batch.go
deleted file mode 100644
index 84acae6..0000000
--- a/batch.go
+++ /dev/null
@@ -1,138 +0,0 @@
-package bolt
-
-import (
- "errors"
- "fmt"
- "sync"
- "time"
-)
-
-// Batch calls fn as part of a batch. It behaves similar to Update,
-// except:
-//
-// 1. concurrent Batch calls can be combined into a single Bolt
-// transaction.
-//
-// 2. the function passed to Batch may be called multiple times,
-// regardless of whether it returns error or not.
-//
-// This means that Batch function side effects must be idempotent and
-// take permanent effect only after a successful return is seen in
-// caller.
-//
-// The maximum batch size and delay can be adjusted with DB.MaxBatchSize
-// and DB.MaxBatchDelay, respectively.
-//
-// Batch is only useful when there are multiple goroutines calling it.
-func (db *DB) Batch(fn func(*Tx) error) error {
- errCh := make(chan error, 1)
-
- db.batchMu.Lock()
- if (db.batch == nil) || (db.batch != nil && len(db.batch.calls) >= db.MaxBatchSize) {
- // There is no existing batch, or the existing batch is full; start a new one.
- db.batch = &batch{
- db: db,
- }
- db.batch.timer = time.AfterFunc(db.MaxBatchDelay, db.batch.trigger)
- }
- db.batch.calls = append(db.batch.calls, call{fn: fn, err: errCh})
- if len(db.batch.calls) >= db.MaxBatchSize {
- // wake up batch, it's ready to run
- go db.batch.trigger()
- }
- db.batchMu.Unlock()
-
- err := <-errCh
- if err == trySolo {
- err = db.Update(fn)
- }
- return err
-}
-
-type call struct {
- fn func(*Tx) error
- err chan<- error
-}
-
-type batch struct {
- db *DB
- timer *time.Timer
- start sync.Once
- calls []call
-}
-
-// trigger runs the batch if it hasn't already been run.
-func (b *batch) trigger() {
- b.start.Do(b.run)
-}
-
-// run performs the transactions in the batch and communicates results
-// back to DB.Batch.
-func (b *batch) run() {
- b.db.batchMu.Lock()
- b.timer.Stop()
- // Make sure no new work is added to this batch, but don't break
- // other batches.
- if b.db.batch == b {
- b.db.batch = nil
- }
- b.db.batchMu.Unlock()
-
-retry:
- for len(b.calls) > 0 {
- var failIdx = -1
- err := b.db.Update(func(tx *Tx) error {
- for i, c := range b.calls {
- if err := safelyCall(c.fn, tx); err != nil {
- failIdx = i
- return err
- }
- }
- return nil
- })
-
- if failIdx >= 0 {
- // take the failing transaction out of the batch. it's
- // safe to shorten b.calls here because db.batch no longer
- // points to us, and we hold the mutex anyway.
- c := b.calls[failIdx]
- b.calls[failIdx], b.calls = b.calls[len(b.calls)-1], b.calls[:len(b.calls)-1]
- // tell the submitter re-run it solo, continue with the rest of the batch
- c.err <- trySolo
- continue retry
- }
-
- // pass success, or bolt internal errors, to all callers
- for _, c := range b.calls {
- if c.err != nil {
- c.err <- err
- }
- }
- break retry
- }
-}
-
-// trySolo is a special sentinel error value used for signaling that a
-// transaction function should be re-run. It should never be seen by
-// callers.
-var trySolo = errors.New("batch function returned an error and should be re-run solo")
-
-type panicked struct {
- reason interface{}
-}
-
-func (p panicked) Error() string {
- if err, ok := p.reason.(error); ok {
- return err.Error()
- }
- return fmt.Sprintf("panic: %v", p.reason)
-}
-
-func safelyCall(fn func(*Tx) error, tx *Tx) (err error) {
- defer func() {
- if p := recover(); p != nil {
- err = panicked{p}
- }
- }()
- return fn(tx)
-}