Fix function delete with uid (#142)

If no uid is provided, all versions of function files and function metadata will be deleted.  If a uid is provided, only that specific version is deleted, and the "latest" version of the function moves back to the previous one.

Fixes #152

controller/api_test.go

@@ -126,6 +126,61 @@ func TestFunctionApi(t *testing.T) {
 	panicIf(err)
 }
 
+func TestFunctionVersionApi(t *testing.T) {
+	testFunc := &fission.Function{
+		Metadata: fission.Metadata{
+			Name: "foo",
+			Uid:  "",
+		},
+		Environment: fission.Metadata{
+			Name: "nodejs",
+			Uid:  "xxx",
+		},
+		Code: "code1",
+	}
+
+	testFunc.Code = "code1"
+	m, err := g.client.FunctionCreate(testFunc)
+	panicIf(err)
+	uid1 := m.Uid
+
+	testFunc.Code = "code2"
+	m, err = g.client.FunctionUpdate(testFunc)
+	panicIf(err)
+	uid2 := m.Uid
+
+	err = g.client.FunctionDelete(&fission.Metadata{Name: "foo", Uid: uid1})
+	panicIf(err)
+
+	f, err := g.client.FunctionGet(&fission.Metadata{Name: "foo"})
+	panicIf(err)
+	assert(f.Metadata.Uid == uid2, "deleted version1, but version2 does not exist")
+
+	testFunc.Code = "code3"
+	m, err = g.client.FunctionUpdate(testFunc)
+	panicIf(err)
+	uid3 := m.Uid
+
+	err = g.client.FunctionDelete(&fission.Metadata{Name: "foo", Uid: uid3})
+	panicIf(err)
+
+	f, err = g.client.FunctionGet(&fission.Metadata{Name: "foo"})
+	panicIf(err)
+	assert(f.Metadata.Uid == uid2, "deleted version3, but version2 does not exist")
+
+	testFunc.Code = "code4"
+	m, err = g.client.FunctionUpdate(testFunc)
+	panicIf(err)
+
+	err = g.client.FunctionDelete(&fission.Metadata{Name: "foo"})
+	panicIf(err)
+
+	funcs, err := g.client.FunctionList()
+	panicIf(err)
+	assert(len(funcs) == 0,
+		"created one function with two versions(2 and 4), delete without uid but cannot delete them all")
+}
+
 func TestHTTPTriggerApi(t *testing.T) {
 	testTrigger := &fission.HTTPTrigger{
 		Metadata: fission.Metadata{

controller/functionStore.go

@@ -108,7 +108,26 @@ func (fs *FunctionStore) Delete(m fission.Metadata) error {
 	if err != nil {
 		return err
 	}
-	return fs.ResourceStore.delete(typeName, m.Name)
+
+	bufs, err := fs.ResourceStore.getAll("file/" + m.Name)
+	if err != nil {
+		return err
+	}
+	if len(bufs) == 0 {
+		return fs.ResourceStore.delete(typeName, m.Name)
+	}
+
+	fnew, err := fs.Get(&fission.Metadata{Name: m.Name})
+	if err != nil {
+		return err
+	}
+
+	latestUid := bufs[len(bufs)-1] // function always tracks the latest version of code
+	if latestUid == fnew.Uid {
+		return nil
+	}
+	fnew.Uid = latestUid
+	return fs.ResourceStore.update(fnew)
 }
 
 func (fs *FunctionStore) List() ([]fission.Function, error) {

controller/resourceStore.go

@@ -139,7 +139,7 @@ func (rs *ResourceStore) delete(typename, rkey string) error {
 // getAll finds all entries under key.  If none or found or key
 // doesn't exist, returns an empty slice.
 func (rs *ResourceStore) getAll(key string) ([]string, error) {
-	resp, err := rs.KeysAPI.Get(context.Background(), key, &client.GetOptions{Recursive: true})
+	resp, err := rs.KeysAPI.Get(context.Background(), key, &client.GetOptions{Recursive: true, Sort: true})
 	if err != nil {
 		if client.IsKeyNotFound(err) {
 			return []string{}, nil