Merge pull request #65 from rgooch/master

lib/filegen: fix concurrency bug and add unittest.

lib/filegen/register.go

@@ -37,14 +37,18 @@ func (m *Manager) registerHashGeneratorForPath(pathname string,
 	pathMgr := &pathManager{
 		generator:     gen,
 		machineHashes: make(map[string]expiringHash)}
+	m.rwMutex.Lock()
 	m.pathManagers[pathname] = pathMgr
+	m.rwMutex.Unlock()
 	go m.processPathDataInvalidations(pathname, notifyChan)
 	return notifyChan
 }
 
 func (m *Manager) processPathDataInvalidations(pathname string,
 	machineNameChannel <-chan string) {
+	m.rwMutex.RLock()
 	pathMgr := m.pathManagers[pathname]
+	m.rwMutex.RUnlock()
 	for machineName := range machineNameChannel {
 		pathMgr.rwMutex.Lock()
 		if machineName == "" {

lib/filegen/register_test.go

@@ -0,0 +1,32 @@
+package filegen
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/Cloud-Foundations/Dominator/lib/log"
+	"github.com/Cloud-Foundations/Dominator/lib/log/testlogger"
+	"github.com/Cloud-Foundations/Dominator/lib/mdb"
+)
+
+type testGenerator struct{}
+
+var testData = []byte("data")
+
+func (g *testGenerator) Generate(machine mdb.Machine, logger log.Logger) (
+	data []byte, validUntil time.Time, err error) {
+	return testData, time.Now().Add(time.Minute), nil
+}
+
+func TestManyRegisters(t *testing.T) {
+	m := New(testlogger.New(t))
+	dataGenerator := &testGenerator{}
+	var pathnames []string
+	for count := 0; count < 100; count++ {
+		pathnames = append(pathnames, fmt.Sprintf("dir/file%d", count))
+	}
+	for _, pathname := range pathnames {
+		m.RegisterGeneratorForPath(pathname, dataGenerator)
+	}
+}