feat: publish Subscribe function

Signed-off-by: Ben Meier <[email protected]>

Makefile

@@ -22,7 +22,7 @@ help:
 ## Execute Go tests with gotestsum (go install gotest.tools/gotestsum@latest)
 .PHONY: test
 test:
-	gotestsum --format testname
+	gotestsum --format testname -- -race
 
 ## Lint Go code with golangci-lint (install this if you don't have it)
 .PHONY: lint

client.go

@@ -138,7 +138,7 @@ func (b *SharedDoc) HttpPushPullChanges(ctx context.Context, url string, opts ..
 	wg := new(sync.WaitGroup)
 	defer wg.Wait()
 
-	sub, fin := b.subscribeToReceivedChanges()
+	sub, fin := b.SubscribeToReceivedChanges()
 	defer fin()
 
 	ctx, cancel := context.WithCancel(ctx)

read_test.go

@@ -22,7 +22,7 @@ func TestNotifyPossibleChanges_with_sub(t *testing.T) {
 	t.Parallel()
 
 	a := NewSharedDoc(automerge.New())
-	sub, fin := a.subscribeToReceivedChanges()
+	sub, fin := a.SubscribeToReceivedChanges()
 
 	t.Run("no message available by default", func(t *testing.T) {
 		select {

server.go

@@ -107,7 +107,7 @@ func (b *SharedDoc) ServeChanges(rw http.ResponseWriter, req *http.Request, opts
 	wg := new(sync.WaitGroup)
 	defer wg.Wait()
 
-	sub, fin := b.subscribeToReceivedChanges()
+	sub, fin := b.SubscribeToReceivedChanges()
 	defer fin()
 
 	// We piggyback on the context and ensure we cancel it before waiting for the wait group.

write.go

@@ -12,7 +12,9 @@ import (
 	"github.com/automerge/automerge-go"
 )
 
-func (b *SharedDoc) subscribeToReceivedChanges() (chan bool, func()) {
+// SubscribeToReceivedChanges allows the caller to subscribe to changes received by the doc. Call the finish function
+// to clean up.
+func (b *SharedDoc) SubscribeToReceivedChanges() (chan bool, func()) {
 	b.mutex.Lock()
 	defer b.mutex.Unlock()
 	if b.channels == nil {