update docs

1 files changed, 8 insertions, 3 deletions

diff --git a/skate/zipkey/batch.go b/skate/zipkey/batch.go
index 9e52f90..ebbd081 100644
--- a/skate/zipkey/batch.go
+++ b/skate/zipkey/batch.go
@@ -14,7 +14,7 @@ type Batcher struct {
 	queue      chan []*Group
 	wg         sync.WaitGroup
 	err        error
-	closing    bool
+	closing    bool // https://stackoverflow.com/q/16105325/89391
 }
 
 // NewBatcher set ups a new Batcher.
@@ -32,6 +32,8 @@ func NewBatcher(gf groupFunc) *Batcher {
 	return &batcher
 }
 
+// Close tears down the batcher. If this is not called, you get goroutine leaks
+// and will miss the data from the last uncommitted batch.
 func (b *Batcher) Close() error {
 	b.closing = true
 	g := make([]*Group, len(b.batch))
@@ -43,7 +45,8 @@ func (b *Batcher) Close() error {
 	return b.err
 }
 
-// GroupFunc implement the groupFunc type. Not thread safe.
+// GroupFunc implement the groupFunc type. Not thread safe. Panics if called
+// after Close has been called.
 func (b *Batcher) GroupFunc(g *Group) error {
 	if b.closing {
 		panic("cannot call GroupFunc after Close")
@@ -58,7 +61,9 @@ func (b *Batcher) GroupFunc(g *Group) error {
 	return nil
 }
 
-// worker will wind down after a first error encountered.
+// worker will wind down after any error has been encountered. Multiple threads
+// may set the error, but we currently only care whether the error is nil or
+// not.
 func (b *Batcher) worker() {
 	defer b.wg.Done()
 OUTER: