Merge pull request #408 from xiangli-cmu/compareAndDelete

Compare and delete

server/v2/delete_handler.go

@@ -2,7 +2,9 @@ package v2
 
 import (
 	"net/http"
+	"strconv"
 
+	etcdErr "github.com/coreos/etcd/error"
 	"github.com/gorilla/mux"
 )
 
@@ -13,6 +15,35 @@ func DeleteHandler(w http.ResponseWriter, req *http.Request, s Server) error {
 	recursive := (req.FormValue("recursive") == "true")
 	dir := (req.FormValue("dir") == "true")
 
-	c := s.Store().CommandFactory().CreateDeleteCommand(key, dir, recursive)
+	req.ParseForm()
+	_, valueOk := req.Form["prevValue"]
+	_, indexOk := req.Form["prevIndex"]
+
+	if !valueOk && !indexOk {
+		c := s.Store().CommandFactory().CreateDeleteCommand(key, dir, recursive)
+		return s.Dispatch(c, w, req)
+	}
+
+	var err error
+	prevIndex := uint64(0)
+	prevValue := req.Form.Get("prevValue")
+
+	if indexOk {
+		prevIndexStr := req.Form.Get("prevIndex")
+		prevIndex, err = strconv.ParseUint(prevIndexStr, 10, 64)
+
+		// bad previous index
+		if err != nil {
+			return etcdErr.NewError(etcdErr.EcodeIndexNaN, "CompareAndDelete", s.Store().Index())
+		}
+	}
+
+	if valueOk {
+		if prevValue == "" {
+			return etcdErr.NewError(etcdErr.EcodePrevValueRequired, "CompareAndDelete", s.Store().Index())
+		}
+	}
+
+	c := s.Store().CommandFactory().CreateCompareAndDeleteCommand(key, prevValue, prevIndex)
 	return s.Dispatch(c, w, req)
 }

server/v2/tests/delete_handler_test.go

@@ -90,3 +90,114 @@ func TestV2DeleteDirectoryRecursiveImpliesDir(t *testing.T) {
 		assert.Equal(t, string(body), `{"action":"delete","node":{"key":"/foo","dir":true,"modifiedIndex":3,"createdIndex":2}}`, "")
 	})
 }
+
+// Ensures that a key is deleted if the previous index matches
+//
+//   $ curl -X PUT localhost:4001/v2/keys/foo -d value=XXX
+//   $ curl -X DELETE localhost:4001/v2/keys/foo?prevIndex=2
+//
+func TestV2DeleteKeyCADOnIndexSuccess(t *testing.T) {
+	tests.RunServer(func(s *server.Server) {
+		v := url.Values{}
+		v.Set("value", "XXX")
+		resp, err := tests.PutForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo"), v)
+		tests.ReadBody(resp)
+		resp, err = tests.DeleteForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo?prevIndex=2"), url.Values{})
+		assert.Nil(t, err, "")
+		body := tests.ReadBodyJSON(resp)
+		assert.Equal(t, body["action"], "compareAndDelete", "")
+
+		node := body["node"].(map[string]interface{})
+		assert.Equal(t, node["key"], "/foo", "")
+		assert.Equal(t, node["modifiedIndex"], 3, "")
+	})
+}
+
+// Ensures that a key is not deleted if the previous index does not match
+//
+//   $ curl -X PUT localhost:4001/v2/keys/foo -d value=XXX
+//   $ curl -X DELETE localhost:4001/v2/keys/foo?prevIndex=100
+//
+func TestV2DeleteKeyCADOnIndexFail(t *testing.T) {
+	tests.RunServer(func(s *server.Server) {
+		v := url.Values{}
+		v.Set("value", "XXX")
+		resp, err := tests.PutForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo"), v)
+		tests.ReadBody(resp)
+		resp, err = tests.DeleteForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo?prevIndex=100"), url.Values{})
+		assert.Nil(t, err, "")
+		body := tests.ReadBodyJSON(resp)
+		assert.Equal(t, body["errorCode"], 101)
+	})
+}
+
+// Ensures that an error is thrown if an invalid previous index is provided.
+//
+//   $ curl -X PUT localhost:4001/v2/keys/foo/bar -d value=XXX
+//   $ curl -X DELETE localhost:4001/v2/keys/foo/bar?prevIndex=bad_index
+//
+func TestV2DeleteKeyCADWithInvalidIndex(t *testing.T) {
+	tests.RunServer(func(s *server.Server) {
+		v := url.Values{}
+		v.Set("value", "XXX")
+		resp, _ := tests.PutForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar"), v)
+		tests.ReadBody(resp)
+		resp, _ = tests.DeleteForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar?prevIndex=bad_index"), v)
+		body := tests.ReadBodyJSON(resp)
+		assert.Equal(t, body["errorCode"], 203)
+	})
+}
+
+// Ensures that a key is deleted only if the previous value matches.
+//
+//   $ curl -X PUT localhost:4001/v2/keys/foo/bar -d value=XXX
+//   $ curl -X DELETE localhost:4001/v2/keys/foo/bar?prevValue=XXX
+//
+func TestV2DeleteKeyCADOnValueSuccess(t *testing.T) {
+	tests.RunServer(func(s *server.Server) {
+		v := url.Values{}
+		v.Set("value", "XXX")
+		resp, _ := tests.PutForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar"), v)
+		tests.ReadBody(resp)
+		resp, _ = tests.DeleteForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar?prevValue=XXX"), v)
+		body := tests.ReadBodyJSON(resp)
+		assert.Equal(t, body["action"], "compareAndDelete", "")
+
+		node := body["node"].(map[string]interface{})
+		assert.Equal(t, node["modifiedIndex"], 3, "")
+	})
+}
+
+// Ensures that a key is not deleted if the previous value does not match.
+//
+//   $ curl -X PUT localhost:4001/v2/keys/foo/bar -d value=XXX
+//   $ curl -X DELETE localhost:4001/v2/keys/foo/bar?prevValue=YYY
+//
+func TestV2DeleteKeyCADOnValueFail(t *testing.T) {
+	tests.RunServer(func(s *server.Server) {
+		v := url.Values{}
+		v.Set("value", "XXX")
+		resp, _ := tests.PutForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar"), v)
+		tests.ReadBody(resp)
+		resp, _ = tests.DeleteForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar?prevValue=YYY"), v)
+		body := tests.ReadBodyJSON(resp)
+		assert.Equal(t, body["errorCode"], 101)
+	})
+}
+
+// Ensures that an error is thrown if an invalid previous value is provided.
+//
+//   $ curl -X PUT localhost:4001/v2/keys/foo/bar -d value=XXX
+//   $ curl -X DELETE localhost:4001/v2/keys/foo/bar?prevIndex=
+//
+func TestV2DeleteKeyCADWithInvalidValue(t *testing.T) {
+	tests.RunServer(func(s *server.Server) {
+		v := url.Values{}
+		v.Set("value", "XXX")
+		resp, _ := tests.PutForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar"), v)
+		tests.ReadBody(resp)
+		resp, _ = tests.DeleteForm(fmt.Sprintf("%s%s", s.URL(), "/v2/keys/foo/bar?prevValue="), v)
+		body := tests.ReadBodyJSON(resp)
+		assert.Equal(t, body["errorCode"], 201)
+	})
+}

server/v2/tests/get_handler_test.go

@@ -214,7 +214,7 @@ func TestV2WatchKeyInDir(t *testing.T) {
 		}()
 
 		// wait for expiration, we do have a up to 500 millisecond delay
-		time.Sleep(1500 * time.Millisecond)
+		time.Sleep(2000 * time.Millisecond)
 
 		select {
 		case <-c: