chore: rename some function & add more documentation

frontend/rust-lib/flowy-folder/src/manager.rs

@@ -215,7 +215,7 @@ impl DefaultFolderBuilder {
         for app in workspace_rev.apps.iter() {
             for (index, view) in app.belongings.iter().enumerate() {
                 let view_data = if index == 0 {
-                    initial_read_me().to_delta_str()
+                    initial_read_me().to_json_str()
                 } else {
                     initial_quill_delta_string()
                 };

frontend/rust-lib/flowy-folder/src/services/folder_editor.rs

@@ -10,7 +10,7 @@ use flowy_sync::{
     entities::{revision::Revision, ws_data::ServerRevisionWSData},
 };
 use lib_infra::future::FutureResult;
-use lib_ot::core::PlainTextAttributes;
+use lib_ot::core::PhantomAttributes;
 
 use parking_lot::RwLock;
 use std::sync::Arc;
@@ -80,7 +80,7 @@ impl FolderEditor {
     pub(crate) fn apply_change(&self, change: FolderChange) -> FlowyResult<()> {
         let FolderChange { delta, md5 } = change;
         let (base_rev_id, rev_id) = self.rev_manager.next_rev_id_pair();
-        let delta_data = delta.to_delta_bytes();
+        let delta_data = delta.to_json_bytes();
         let revision = Revision::new(
             &self.rev_manager.object_id,
             base_rev_id,
@@ -132,7 +132,7 @@ impl FolderEditor {
 pub struct FolderRevisionCompactor();
 impl RevisionCompactor for FolderRevisionCompactor {
     fn bytes_from_revisions(&self, revisions: Vec<Revision>) -> FlowyResult<Bytes> {
-        let delta = make_delta_from_revisions::<PlainTextAttributes>(revisions)?;
-        Ok(delta.to_delta_bytes())
+        let delta = make_delta_from_revisions::<PhantomAttributes>(revisions)?;
+        Ok(delta.to_json_bytes())
     }
 }

frontend/rust-lib/flowy-folder/src/services/persistence/mod.rs

@@ -110,7 +110,7 @@ impl FolderPersistence {
     pub async fn save_folder(&self, user_id: &str, folder_id: &FolderId, folder: FolderPad) -> FlowyResult<()> {
         let pool = self.database.db_pool()?;
         let json = folder.to_json()?;
-        let delta_data = PlainTextDeltaBuilder::new().insert(&json).build().to_delta_bytes();
+        let delta_data = PlainTextDeltaBuilder::new().insert(&json).build().to_json_bytes();
         let revision = Revision::initial_revision(user_id, folder_id.as_ref(), delta_data);
         let record = RevisionRecord {
             revision,

frontend/rust-lib/flowy-folder/src/services/web_socket.rs

@@ -10,7 +10,7 @@ use flowy_sync::{
     },
 };
 use lib_infra::future::{BoxResultFuture, FutureResult};
-use lib_ot::core::{OperationTransformable, PlainTextAttributes, PlainTextDelta};
+use lib_ot::core::{OperationTransformable, PhantomAttributes, PlainTextDelta};
 use parking_lot::RwLock;
 use std::{sync::Arc, time::Duration};
 
@@ -24,7 +24,7 @@ pub(crate) async fn make_folder_ws_manager(
 ) -> Arc<RevisionWebSocketManager> {
     let ws_data_provider = Arc::new(WSDataProvider::new(folder_id, Arc::new(rev_manager.clone())));
     let resolver = Arc::new(FolderConflictResolver { folder_pad });
-    let conflict_controller = ConflictController::<PlainTextAttributes>::new(
+    let conflict_controller = ConflictController::<PhantomAttributes>::new(
         user_id,
         resolver,
         Arc::new(ws_data_provider.clone()),
@@ -55,7 +55,7 @@ struct FolderConflictResolver {
     folder_pad: Arc<RwLock<FolderPad>>,
 }
 
-impl ConflictResolver<PlainTextAttributes> for FolderConflictResolver {
+impl ConflictResolver<PhantomAttributes> for FolderConflictResolver {
     fn compose_delta(&self, delta: PlainTextDelta) -> BoxResultFuture<DeltaMD5, FlowyError> {
         let folder_pad = self.folder_pad.clone();
         Box::pin(async move {
@@ -67,7 +67,7 @@ impl ConflictResolver<PlainTextAttributes> for FolderConflictResolver {
     fn transform_delta(
         &self,
         delta: PlainTextDelta,
-    ) -> BoxResultFuture<TransformDeltas<PlainTextAttributes>, FlowyError> {
+    ) -> BoxResultFuture<TransformDeltas<PhantomAttributes>, FlowyError> {
         let folder_pad = self.folder_pad.clone();
         Box::pin(async move {
             let read_guard = folder_pad.read();

frontend/rust-lib/flowy-grid/src/manager.rs

@@ -192,7 +192,7 @@ pub async fn make_grid_view_data(
 
         // Create grid's block
         let grid_block_delta = make_grid_block_delta(block_meta_data);
-        let block_delta_data = grid_block_delta.to_delta_bytes();
+        let block_delta_data = grid_block_delta.to_json_bytes();
         let repeated_revision: RepeatedRevision =
             Revision::initial_revision(user_id, block_id, block_delta_data).into();
         let _ = grid_manager.create_grid_block(&block_id, repeated_revision).await?;
@@ -202,7 +202,7 @@ pub async fn make_grid_view_data(
 
     // Create grid
     let grid_meta_delta = make_grid_delta(&grid_rev);
-    let grid_delta_data = grid_meta_delta.to_delta_bytes();
+    let grid_delta_data = grid_meta_delta.to_json_bytes();
     let repeated_revision: RepeatedRevision =
         Revision::initial_revision(user_id, view_id, grid_delta_data.clone()).into();
     let _ = grid_manager.create_grid(view_id, repeated_revision).await?;

frontend/rust-lib/flowy-grid/src/services/block_revision_editor.rs

@@ -7,7 +7,7 @@ use flowy_sync::client_grid::{GridBlockMetaChange, GridBlockRevisionPad};
 use flowy_sync::entities::revision::Revision;
 use flowy_sync::util::make_delta_from_revisions;
 use lib_infra::future::FutureResult;
-use lib_ot::core::PlainTextAttributes;
+use lib_ot::core::PhantomAttributes;
 use std::borrow::Cow;
 use std::sync::Arc;
 use tokio::sync::RwLock;
@@ -161,7 +161,7 @@ impl GridBlockRevisionEditor {
         let GridBlockMetaChange { delta, md5 } = change;
         let user_id = self.user_id.clone();
         let (base_rev_id, rev_id) = self.rev_manager.next_rev_id_pair();
-        let delta_data = delta.to_delta_bytes();
+        let delta_data = delta.to_json_bytes();
         let revision = Revision::new(
             &self.rev_manager.object_id,
             base_rev_id,
@@ -200,7 +200,7 @@ impl RevisionObjectBuilder for GridBlockMetaPadBuilder {
 pub struct GridBlockRevisionCompactor();
 impl RevisionCompactor for GridBlockRevisionCompactor {
     fn bytes_from_revisions(&self, revisions: Vec<Revision>) -> FlowyResult<Bytes> {
-        let delta = make_delta_from_revisions::<PlainTextAttributes>(revisions)?;
-        Ok(delta.to_delta_bytes())
+        let delta = make_delta_from_revisions::<PhantomAttributes>(revisions)?;
+        Ok(delta.to_json_bytes())
     }
 }

frontend/rust-lib/flowy-grid/src/services/grid_editor.rs

@@ -21,7 +21,7 @@ use flowy_sync::entities::revision::Revision;
 use flowy_sync::errors::CollaborateResult;
 use flowy_sync::util::make_delta_from_revisions;
 use lib_infra::future::FutureResult;
-use lib_ot::core::PlainTextAttributes;
+use lib_ot::core::PhantomAttributes;
 use std::collections::HashMap;
 use std::sync::Arc;
 use tokio::sync::RwLock;
@@ -573,7 +573,7 @@ impl GridRevisionEditor {
         let GridChangeset { delta, md5 } = change;
         let user_id = self.user.user_id()?;
         let (base_rev_id, rev_id) = self.rev_manager.next_rev_id_pair();
-        let delta_data = delta.to_delta_bytes();
+        let delta_data = delta.to_json_bytes();
         let revision = Revision::new(
             &self.rev_manager.object_id,
             base_rev_id,
@@ -664,8 +664,8 @@ impl RevisionCloudService for GridRevisionCloudService {
 pub struct GridRevisionCompactor();
 impl RevisionCompactor for GridRevisionCompactor {
     fn bytes_from_revisions(&self, revisions: Vec<Revision>) -> FlowyResult<Bytes> {
-        let delta = make_delta_from_revisions::<PlainTextAttributes>(revisions)?;
-        Ok(delta.to_delta_bytes())
+        let delta = make_delta_from_revisions::<PhantomAttributes>(revisions)?;
+        Ok(delta.to_json_bytes())
     }
 }
 

frontend/rust-lib/flowy-grid/src/services/persistence/migration.rs

@@ -48,7 +48,7 @@ impl GridMigration {
         let pool = self.database.db_pool()?;
         let grid_rev_pad = self.get_grid_revision_pad(grid_id).await?;
         let json = grid_rev_pad.json_str()?;
-        let delta_data = PlainTextDeltaBuilder::new().insert(&json).build().to_delta_bytes();
+        let delta_data = PlainTextDeltaBuilder::new().insert(&json).build().to_json_bytes();
         let revision = Revision::initial_revision(&user_id, grid_id, delta_data);
         let record = RevisionRecord::new(revision);
         //

frontend/rust-lib/flowy-revision/src/conflict_resolve.rs

@@ -9,7 +9,7 @@ use flowy_sync::{
     util::make_delta_from_revisions,
 };
 use lib_infra::future::BoxResultFuture;
-use lib_ot::core::{Attributes, Delta, PlainTextAttributes};
+use lib_ot::core::{Attributes, Delta, PhantomAttributes};
 use lib_ot::rich_text::RichTextAttributes;
 use serde::de::DeserializeOwned;
 use std::{convert::TryFrom, sync::Arc};
@@ -31,7 +31,7 @@ pub trait ConflictRevisionSink: Send + Sync + 'static {
 }
 
 pub type RichTextConflictController = ConflictController<RichTextAttributes>;
-pub type PlainTextConflictController = ConflictController<PlainTextAttributes>;
+pub type PlainTextConflictController = ConflictController<PhantomAttributes>;
 
 pub struct ConflictController<T>
 where
@@ -154,7 +154,7 @@ where
         &rev_manager.object_id,
         base_rev_id,
         rev_id,
-        client_delta.to_delta_bytes(),
+        client_delta.to_json_bytes(),
         user_id,
         md5.clone(),
     );
@@ -166,7 +166,7 @@ where
                 &rev_manager.object_id,
                 base_rev_id,
                 rev_id,
-                server_delta.to_delta_bytes(),
+                server_delta.to_json_bytes(),
                 user_id,
                 md5,
             );

frontend/rust-lib/flowy-text-block/src/editor.rs

@@ -238,7 +238,7 @@ impl RevisionObjectBuilder for TextBlockInfoBuilder {
 
         Result::<DocumentPB, FlowyError>::Ok(DocumentPB {
             block_id: object_id.to_owned(),
-            text: delta.to_delta_str(),
+            text: delta.to_json_str(),
             rev_id,
             base_rev_id,
         })

frontend/rust-lib/flowy-text-block/src/queue.rs

@@ -175,7 +175,7 @@ impl EditBlockQueue {
     }
 
     async fn save_local_delta(&self, delta: RichTextDelta, md5: String) -> Result<RevId, FlowyError> {
-        let delta_data = delta.to_delta_bytes();
+        let delta_data = delta.to_json_bytes();
         let (base_rev_id, rev_id) = self.rev_manager.next_rev_id_pair();
         let user_id = self.user.user_id()?;
         let revision = Revision::new(
@@ -195,7 +195,7 @@ pub(crate) struct TextBlockRevisionCompactor();
 impl RevisionCompactor for TextBlockRevisionCompactor {
     fn bytes_from_revisions(&self, revisions: Vec<Revision>) -> FlowyResult<Bytes> {
         let delta = make_delta_from_revisions::<RichTextAttributes>(revisions)?;
-        Ok(delta.to_delta_bytes())
+        Ok(delta.to_json_bytes())
     }
 }
 

frontend/rust-lib/flowy-text-block/tests/document/script.rs

@@ -75,7 +75,7 @@ impl TextBlockEditorTest {
                 let delta = self.editor.text_block_delta().await.unwrap();
                 if expected_delta != delta {
                     eprintln!("✅ expect: {}", expected,);
-                    eprintln!("❌ receive: {}", delta.to_delta_str());
+                    eprintln!("❌ receive: {}", delta.to_json_str());
                 }
                 assert_eq!(expected_delta, delta);
             }

frontend/rust-lib/flowy-text-block/tests/editor/attribute_test.rs

@@ -762,19 +762,19 @@ fn attributes_preserve_list_format_on_merge() {
 
 #[test]
 fn delta_compose() {
-    let mut delta = RichTextDelta::from_delta_str(r#"[{"insert":"\n"}]"#).unwrap();
+    let mut delta = RichTextDelta::from_json_str(r#"[{"insert":"\n"}]"#).unwrap();
     let deltas = vec![
-        RichTextDelta::from_delta_str(r#"[{"retain":1,"attributes":{"list":"unchecked"}}]"#).unwrap(),
-        RichTextDelta::from_delta_str(r#"[{"insert":"a"}]"#).unwrap(),
-        RichTextDelta::from_delta_str(r#"[{"retain":1},{"insert":"\n","attributes":{"list":"unchecked"}}]"#).unwrap(),
-        RichTextDelta::from_delta_str(r#"[{"retain":2},{"retain":1,"attributes":{"list":""}}]"#).unwrap(),
+        RichTextDelta::from_json_str(r#"[{"retain":1,"attributes":{"list":"unchecked"}}]"#).unwrap(),
+        RichTextDelta::from_json_str(r#"[{"insert":"a"}]"#).unwrap(),
+        RichTextDelta::from_json_str(r#"[{"retain":1},{"insert":"\n","attributes":{"list":"unchecked"}}]"#).unwrap(),
+        RichTextDelta::from_json_str(r#"[{"retain":2},{"retain":1,"attributes":{"list":""}}]"#).unwrap(),
     ];
 
     for d in deltas {
         delta = delta.compose(&d).unwrap();
     }
     assert_eq!(
-        delta.to_delta_str(),
+        delta.to_json_str(),
         r#"[{"insert":"a"},{"insert":"\n","attributes":{"list":"unchecked"}},{"insert":"\n"}]"#
     );
 

frontend/rust-lib/flowy-text-block/tests/editor/mod.rs

@@ -108,20 +108,20 @@ impl TestBuilder {
             TestOp::Insert(delta_i, s, index) => {
                 let document = &mut self.documents[*delta_i];
                 let delta = document.insert(*index, s).unwrap();
-                tracing::debug!("Insert delta: {}", delta.to_delta_str());
+                tracing::debug!("Insert delta: {}", delta.to_json_str());
 
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::Delete(delta_i, iv) => {
                 let document = &mut self.documents[*delta_i];
                 let delta = document.replace(*iv, "").unwrap();
-                tracing::trace!("Delete delta: {}", delta.to_delta_str());
+                tracing::trace!("Delete delta: {}", delta.to_json_str());
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::Replace(delta_i, iv, s) => {
                 let document = &mut self.documents[*delta_i];
                 let delta = document.replace(*iv, s).unwrap();
-                tracing::trace!("Replace delta: {}", delta.to_delta_str());
+                tracing::trace!("Replace delta: {}", delta.to_json_str());
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::InsertBold(delta_i, s, iv) => {
@@ -133,7 +133,7 @@ impl TestBuilder {
                 let document = &mut self.documents[*delta_i];
                 let attribute = RichTextAttribute::Bold(*enable);
                 let delta = document.format(*iv, attribute).unwrap();
-                tracing::trace!("Bold delta: {}", delta.to_delta_str());
+                tracing::trace!("Bold delta: {}", delta.to_json_str());
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::Italic(delta_i, iv, enable) => {
@@ -143,28 +143,28 @@ impl TestBuilder {
                     false => RichTextAttribute::Italic(false),
                 };
                 let delta = document.format(*iv, attribute).unwrap();
-                tracing::trace!("Italic delta: {}", delta.to_delta_str());
+                tracing::trace!("Italic delta: {}", delta.to_json_str());
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::Header(delta_i, iv, level) => {
                 let document = &mut self.documents[*delta_i];
                 let attribute = RichTextAttribute::Header(*level);
                 let delta = document.format(*iv, attribute).unwrap();
-                tracing::trace!("Header delta: {}", delta.to_delta_str());
+                tracing::trace!("Header delta: {}", delta.to_json_str());
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::Link(delta_i, iv, link) => {
                 let document = &mut self.documents[*delta_i];
                 let attribute = RichTextAttribute::Link(link.to_owned());
                 let delta = document.format(*iv, attribute).unwrap();
-                tracing::trace!("Link delta: {}", delta.to_delta_str());
+                tracing::trace!("Link delta: {}", delta.to_json_str());
                 self.deltas.insert(*delta_i, Some(delta));
             }
             TestOp::Bullet(delta_i, iv, enable) => {
                 let document = &mut self.documents[*delta_i];
                 let attribute = RichTextAttribute::Bullet(*enable);
                 let delta = document.format(*iv, attribute).unwrap();
-                tracing::debug!("Bullet delta: {}", delta.to_delta_str());
+                tracing::debug!("Bullet delta: {}", delta.to_json_str());
 
                 self.deltas.insert(*delta_i, Some(delta));
             }
@@ -194,15 +194,15 @@ impl TestBuilder {
                 let delta_a = &self.documents[*delta_a_i].delta();
                 let delta_b = &self.documents[*delta_b_i].delta();
                 tracing::debug!("Invert: ");
-                tracing::debug!("a: {}", delta_a.to_delta_str());
-                tracing::debug!("b: {}", delta_b.to_delta_str());
+                tracing::debug!("a: {}", delta_a.to_json_str());
+                tracing::debug!("b: {}", delta_b.to_json_str());
 
                 let (_, b_prime) = delta_a.transform(delta_b).unwrap();
                 let undo = b_prime.invert(delta_a);
 
                 let new_delta = delta_a.compose(&b_prime).unwrap();
-                tracing::debug!("new delta: {}", new_delta.to_delta_str());
-                tracing::debug!("undo delta: {}", undo.to_delta_str());
+                tracing::debug!("new delta: {}", new_delta.to_json_str());
+                tracing::debug!("undo delta: {}", undo.to_json_str());
 
                 let new_delta_after_undo = new_delta.compose(&undo).unwrap();
 
@@ -238,7 +238,7 @@ impl TestBuilder {
             }
 
             TestOp::AssertPrimeJson(doc_i, expected) => {
-                let prime_json = self.primes[*doc_i].as_ref().unwrap().to_delta_str();
+                let prime_json = self.primes[*doc_i].as_ref().unwrap().to_json_str();
                 let expected_prime: RichTextDelta = serde_json::from_str(expected).unwrap();
                 let target_prime: RichTextDelta = serde_json::from_str(&prime_json).unwrap();
 

frontend/rust-lib/flowy-text-block/tests/editor/op_test.rs

@@ -378,7 +378,7 @@ fn apply_test() {
         .insert(", AppFlowy")
         .build();
 
-    let after_a = delta_a.to_str().unwrap();
+    let after_a = delta_a.content_str().unwrap();
     let after_b = delta_b.apply(&after_a).unwrap();
     assert_eq!("hello, AppFlowy", &after_b);
 }

frontend/rust-lib/flowy-text-block/tests/editor/serde_test.rs

@@ -65,7 +65,7 @@ fn delta_serialize_multi_attribute_test() {
     let json = serde_json::to_string(&delta).unwrap();
     eprintln!("{}", json);
 
-    let delta_from_json = Delta::from_delta_str(&json).unwrap();
+    let delta_from_json = Delta::from_json_str(&json).unwrap();
     assert_eq!(delta_from_json, delta);
 }
 
@@ -77,7 +77,7 @@ fn delta_deserialize_test() {
         {"retain":2,"attributes":{"italic":"true","bold":"true"}},
         {"retain":2,"attributes":{"italic":true,"bold":true}}
      ]"#;
-    let delta = RichTextDelta::from_delta_str(json).unwrap();
+    let delta = RichTextDelta::from_json_str(json).unwrap();
     eprintln!("{}", delta);
 }
 
@@ -86,13 +86,13 @@ fn delta_deserialize_null_test() {
     let json = r#"[
         {"retain":7,"attributes":{"bold":null}}
      ]"#;
-    let delta1 = RichTextDelta::from_delta_str(json).unwrap();
+    let delta1 = RichTextDelta::from_json_str(json).unwrap();
 
     let mut attribute = RichTextAttribute::Bold(true);
     attribute.value = RichTextAttributeValue(None);
     let delta2 = DeltaBuilder::new().retain_with_attributes(7, attribute.into()).build();
 
-    assert_eq!(delta2.to_delta_str(), r#"[{"retain":7,"attributes":{"bold":""}}]"#);
+    assert_eq!(delta2.to_json_str(), r#"[{"retain":7,"attributes":{"bold":""}}]"#);
     assert_eq!(delta1, delta2);
 }
 

shared-lib/flowy-sync/src/client_document/default/mod.rs

@@ -7,13 +7,13 @@ pub fn initial_quill_delta() -> RichTextDelta {
 
 #[inline]
 pub fn initial_quill_delta_string() -> String {
-    initial_quill_delta().to_delta_str()
+    initial_quill_delta().to_json_str()
 }
 
 #[inline]
 pub fn initial_read_me() -> RichTextDelta {
     let json = include_str!("READ_ME.json");
-    RichTextDelta::from_delta_str(json).unwrap()
+    RichTextDelta::from_json_str(json).unwrap()
 }
 
 #[cfg(test)]
@@ -22,6 +22,6 @@ mod tests {
 
     #[test]
     fn load_read_me() {
-        println!("{}", initial_read_me().to_delta_str());
+        println!("{}", initial_read_me().to_json_str());
     }
 }

shared-lib/flowy-sync/src/client_document/document_pad.rs

@@ -55,16 +55,16 @@ impl ClientDocument {
     }
 
     pub fn from_json(json: &str) -> Result<Self, CollaborateError> {
-        let delta = RichTextDelta::from_delta_str(json)?;
+        let delta = RichTextDelta::from_json_str(json)?;
         Ok(Self::from_delta(delta))
     }
 
     pub fn delta_str(&self) -> String {
-        self.delta.to_delta_str()
+        self.delta.to_json_str()
     }
 
     pub fn to_bytes(&self) -> Bytes {
-        self.delta.to_delta_bytes()
+        self.delta.to_json_bytes()
     }
 
     pub fn to_plain_string(&self) -> String {
@@ -85,7 +85,7 @@ impl ClientDocument {
     }
 
     pub fn set_delta(&mut self, data: RichTextDelta) {
-        tracing::trace!("document: {}", data.to_delta_str());
+        tracing::trace!("document: {}", data.to_json_str());
         self.delta = data;
 
         match &self.notify {
@@ -97,7 +97,7 @@ impl ClientDocument {
     }
 
     pub fn compose_delta(&mut self, delta: RichTextDelta) -> Result<(), CollaborateError> {
-        tracing::trace!("{} compose {}", &self.delta.to_delta_str(), delta.to_delta_str());
+        tracing::trace!("{} compose {}", &self.delta.to_json_str(), delta.to_json_str());
         let composed_delta = self.delta.compose(&delta)?;
         let mut undo_delta = delta.invert(&self.delta);
 

shared-lib/flowy-sync/src/client_folder/builder.rs

@@ -7,7 +7,7 @@ use crate::{
 };
 
 use flowy_folder_data_model::revision::{TrashRevision, WorkspaceRevision};
-use lib_ot::core::{PlainTextAttributes, PlainTextDelta, PlainTextDeltaBuilder};
+use lib_ot::core::{PhantomAttributes, PlainTextDelta, PlainTextDeltaBuilder};
 use serde::{Deserialize, Serialize};
 use std::sync::Arc;
 
@@ -41,9 +41,9 @@ impl FolderPadBuilder {
         }
 
         // TODO: Reconvert from history if delta.to_str() failed.
-        let folder_json = delta.to_str()?;
-        let mut folder: FolderPad = serde_json::from_str(&folder_json).map_err(|e| {
-            tracing::error!("Deserialize folder from json failed: {}", folder_json);
+        let content = delta.content_str()?;
+        let mut folder: FolderPad = serde_json::from_str(&content).map_err(|e| {
+            tracing::error!("Deserialize folder from {} failed", content);
             return CollaborateError::internal().context(format!("Deserialize delta to folder failed: {}", e));
         })?;
         folder.delta = delta;
@@ -51,7 +51,7 @@ impl FolderPadBuilder {
     }
 
     pub(crate) fn build_with_revisions(self, revisions: Vec<Revision>) -> CollaborateResult<FolderPad> {
-        let folder_delta: FolderDelta = make_delta_from_revisions::<PlainTextAttributes>(revisions)?;
+        let folder_delta: FolderDelta = make_delta_from_revisions::<PhantomAttributes>(revisions)?;
         self.build_with_delta(folder_delta)
     }
 

shared-lib/flowy-sync/src/client_folder/folder_pad.rs

@@ -295,7 +295,7 @@ impl FolderPad {
     }
 
     pub fn md5(&self) -> String {
-        md5(&self.delta.to_delta_bytes())
+        md5(&self.delta.to_json_bytes())
     }
 
     pub fn to_json(&self) -> CollaborateResult<String> {
@@ -315,7 +315,7 @@ impl FolderPad {
             Some(_) => {
                 let old = cloned_self.to_json()?;
                 let new = self.to_json()?;
-                match cal_diff::<PlainTextAttributes>(old, new) {
+                match cal_diff::<PhantomAttributes>(old, new) {
                     None => Ok(None),
                     Some(delta) => {
                         self.delta = self.delta.compose(&delta)?;
@@ -350,7 +350,7 @@ impl FolderPad {
             Some(_) => {
                 let old = cloned_self.to_json()?;
                 let new = self.to_json()?;
-                match cal_diff::<PlainTextAttributes>(old, new) {
+                match cal_diff::<PhantomAttributes>(old, new) {
                     None => Ok(None),
                     Some(delta) => {
                         self.delta = self.delta.compose(&delta)?;

shared-lib/flowy-sync/src/client_grid/grid_block_revsion_pad.rs

@@ -4,7 +4,7 @@ use crate::util::{cal_diff, make_delta_from_revisions};
 use flowy_grid_data_model::revision::{
     gen_block_id, gen_row_id, CellRevision, GridBlockRevision, RowMetaChangeset, RowRevision,
 };
-use lib_ot::core::{OperationTransformable, PlainTextAttributes, PlainTextDelta, PlainTextDeltaBuilder};
+use lib_ot::core::{OperationTransformable, PhantomAttributes, PlainTextDelta, PlainTextDeltaBuilder};
 use std::borrow::Cow;
 use std::collections::HashMap;
 use std::sync::Arc;
@@ -46,7 +46,7 @@ impl GridBlockRevisionPad {
     }
 
     pub fn from_delta(delta: GridBlockRevisionDelta) -> CollaborateResult<Self> {
-        let s = delta.to_str()?;
+        let s = delta.content_str()?;
         let block_revision: GridBlockRevision = serde_json::from_str(&s).map_err(|e| {
             let msg = format!("Deserialize delta to block meta failed: {}", e);
             tracing::error!("{}", s);
@@ -56,7 +56,7 @@ impl GridBlockRevisionPad {
     }
 
     pub fn from_revisions(_grid_id: &str, revisions: Vec<Revision>) -> CollaborateResult<Self> {
-        let block_delta: GridBlockRevisionDelta = make_delta_from_revisions::<PlainTextAttributes>(revisions)?;
+        let block_delta: GridBlockRevisionDelta = make_delta_from_revisions::<PhantomAttributes>(revisions)?;
         Self::from_delta(block_delta)
     }
 
@@ -195,10 +195,10 @@ impl GridBlockRevisionPad {
             Some(_) => {
                 let old = cloned_self.to_json()?;
                 let new = self.to_json()?;
-                match cal_diff::<PlainTextAttributes>(old, new) {
+                match cal_diff::<PhantomAttributes>(old, new) {
                     None => Ok(None),
                     Some(delta) => {
-                        tracing::trace!("[GridBlockMeta] Composing delta {}", delta.to_delta_str());
+                        tracing::trace!("[GridBlockMeta] Composing delta {}", delta.to_json_str());
                         // tracing::debug!(
                         //     "[GridBlockMeta] current delta: {}",
                         //     self.delta.to_str().unwrap_or_else(|_| "".to_string())
@@ -231,11 +231,11 @@ impl GridBlockRevisionPad {
     }
 
     pub fn md5(&self) -> String {
-        md5(&self.delta.to_delta_bytes())
+        md5(&self.delta.to_json_bytes())
     }
 
     pub fn delta_str(&self) -> String {
-        self.delta.to_delta_str()
+        self.delta.to_json_str()
     }
 }
 
@@ -252,7 +252,7 @@ pub fn make_grid_block_delta(block_rev: &GridBlockRevision) -> GridBlockRevision
 
 pub fn make_grid_block_revisions(user_id: &str, grid_block_meta_data: &GridBlockRevision) -> RepeatedRevision {
     let delta = make_grid_block_delta(grid_block_meta_data);
-    let bytes = delta.to_delta_bytes();
+    let bytes = delta.to_json_bytes();
     let revision = Revision::initial_revision(user_id, &grid_block_meta_data.block_id, bytes);
     revision.into()
 }
@@ -289,7 +289,7 @@ mod tests {
         let change = pad.add_row_rev(row.clone(), None).unwrap().unwrap();
         assert_eq!(pad.rows.first().unwrap().as_ref(), &row);
         assert_eq!(
-            change.delta.to_delta_str(),
+            change.delta.to_json_str(),
             r#"[{"retain":24},{"insert":"{\"id\":\"1\",\"block_id\":\"1\",\"cells\":[],\"height\":0,\"visibility\":false}"},{"retain":2}]"#
         );
     }
@@ -303,19 +303,19 @@ mod tests {
 
         let change = pad.add_row_rev(row_1.clone(), None).unwrap().unwrap();
         assert_eq!(
-            change.delta.to_delta_str(),
+            change.delta.to_json_str(),
             r#"[{"retain":24},{"insert":"{\"id\":\"1\",\"block_id\":\"1\",\"cells\":[],\"height\":0,\"visibility\":false}"},{"retain":2}]"#
         );
 
         let change = pad.add_row_rev(row_2.clone(), None).unwrap().unwrap();
         assert_eq!(
-            change.delta.to_delta_str(),
+            change.delta.to_json_str(),
             r#"[{"retain":90},{"insert":",{\"id\":\"2\",\"block_id\":\"1\",\"cells\":[],\"height\":0,\"visibility\":false}"},{"retain":2}]"#
         );
 
         let change = pad.add_row_rev(row_3.clone(), Some("2".to_string())).unwrap().unwrap();
         assert_eq!(
-            change.delta.to_delta_str(),
+            change.delta.to_json_str(),
             r#"[{"retain":157},{"insert":",{\"id\":\"3\",\"block_id\":\"1\",\"cells\":[],\"height\":0,\"visibility\":false}"},{"retain":2}]"#
         );
 
@@ -381,7 +381,7 @@ mod tests {
         let _ = pad.add_row_rev(row.clone(), None).unwrap().unwrap();
         let change = pad.delete_rows(vec![Cow::Borrowed(&row.id)]).unwrap().unwrap();
         assert_eq!(
-            change.delta.to_delta_str(),
+            change.delta.to_json_str(),
             r#"[{"retain":24},{"delete":66},{"retain":2}]"#
         );
 
@@ -410,7 +410,7 @@ mod tests {
         let change = pad.update_row(changeset).unwrap().unwrap();
 
         assert_eq!(
-            change.delta.to_delta_str(),
+            change.delta.to_json_str(),
             r#"[{"retain":69},{"insert":"10"},{"retain":15},{"insert":"tru"},{"delete":4},{"retain":4}]"#
         );
 
@@ -422,7 +422,7 @@ mod tests {
 
     fn test_pad() -> GridBlockRevisionPad {
         let delta =
-            GridBlockRevisionDelta::from_delta_str(r#"[{"insert":"{\"block_id\":\"1\",\"rows\":[]}"}]"#).unwrap();
+            GridBlockRevisionDelta::from_json_str(r#"[{"insert":"{\"block_id\":\"1\",\"rows\":[]}"}]"#).unwrap();
         GridBlockRevisionPad::from_delta(delta).unwrap()
     }
 }

shared-lib/flowy-sync/src/client_grid/grid_revision_pad.rs

@@ -9,7 +9,7 @@ use flowy_grid_data_model::revision::{
     GridLayoutRevision, GridRevision, GridSettingRevision, GridSortRevision,
 };
 use lib_infra::util::move_vec_element;
-use lib_ot::core::{OperationTransformable, PlainTextAttributes, PlainTextDelta, PlainTextDeltaBuilder};
+use lib_ot::core::{OperationTransformable, PhantomAttributes, PlainTextDelta, PlainTextDeltaBuilder};
 use std::collections::HashMap;
 use std::sync::Arc;
 
@@ -52,8 +52,8 @@ impl GridRevisionPad {
     }
 
     pub fn from_delta(delta: GridRevisionDelta) -> CollaborateResult<Self> {
-        let s = delta.to_str()?;
-        let grid: GridRevision = serde_json::from_str(&s)
+        let content = delta.content_str()?;
+        let grid: GridRevision = serde_json::from_str(&content)
             .map_err(|e| CollaborateError::internal().context(format!("Deserialize delta to grid failed: {}", e)))?;
 
         Ok(Self {
@@ -63,7 +63,7 @@ impl GridRevisionPad {
     }
 
     pub fn from_revisions(revisions: Vec<Revision>) -> CollaborateResult<Self> {
-        let grid_delta: GridRevisionDelta = make_delta_from_revisions::<PlainTextAttributes>(revisions)?;
+        let grid_delta: GridRevisionDelta = make_delta_from_revisions::<PhantomAttributes>(revisions)?;
         Self::from_delta(grid_delta)
     }
 
@@ -457,15 +457,15 @@ impl GridRevisionPad {
     }
 
     pub fn md5(&self) -> String {
-        md5(&self.delta.to_delta_bytes())
+        md5(&self.delta.to_json_bytes())
     }
 
     pub fn delta_str(&self) -> String {
-        self.delta.to_delta_str()
+        self.delta.to_json_str()
     }
 
     pub fn delta_bytes(&self) -> Bytes {
-        self.delta.to_delta_bytes()
+        self.delta.to_json_bytes()
     }
 
     pub fn fields(&self) -> &[Arc<FieldRevision>] {
@@ -482,7 +482,7 @@ impl GridRevisionPad {
             Some(_) => {
                 let old = make_grid_rev_json_str(&cloned_grid)?;
                 let new = self.json_str()?;
-                match cal_diff::<PlainTextAttributes>(old, new) {
+                match cal_diff::<PhantomAttributes>(old, new) {
                     None => Ok(None),
                     Some(delta) => {
                         self.delta = self.delta.compose(&delta)?;
@@ -553,7 +553,7 @@ pub fn make_grid_delta(grid_rev: &GridRevision) -> GridRevisionDelta {
 
 pub fn make_grid_revisions(user_id: &str, grid_rev: &GridRevision) -> RepeatedRevision {
     let delta = make_grid_delta(grid_rev);
-    let bytes = delta.to_delta_bytes();
+    let bytes = delta.to_json_bytes();
     let revision = Revision::initial_revision(user_id, &grid_rev.grid_id, bytes);
     revision.into()
 }

shared-lib/flowy-sync/src/entities/revision.rs

@@ -89,7 +89,7 @@ impl std::fmt::Debug for Revision {
         let _ = f.write_fmt(format_args!("rev_id {}, ", self.rev_id))?;
         match RichTextDelta::from_bytes(&self.delta_data) {
             Ok(delta) => {
-                let _ = f.write_fmt(format_args!("delta {:?}", delta.to_delta_str()))?;
+                let _ = f.write_fmt(format_args!("delta {:?}", delta.to_json_str()))?;
             }
             Err(e) => {
                 let _ = f.write_fmt(format_args!("delta {:?}", e))?;

shared-lib/flowy-sync/src/entities/text_block.rs

@@ -46,7 +46,7 @@ impl std::convert::TryFrom<Revision> for DocumentPB {
         }
 
         let delta = RichTextDelta::from_bytes(&revision.delta_data)?;
-        let doc_json = delta.to_delta_str();
+        let doc_json = delta.to_json_str();
 
         Ok(DocumentPB {
             block_id: revision.object_id,

shared-lib/flowy-sync/src/server_document/document_pad.rs

@@ -39,7 +39,7 @@ impl RevisionSyncObject<RichTextAttributes> for ServerDocument {
     }
 
     fn to_json(&self) -> String {
-        self.delta.to_delta_str()
+        self.delta.to_json_str()
     }
 
     fn set_delta(&mut self, new_delta: Delta<RichTextAttributes>) {

shared-lib/flowy-sync/src/server_folder/folder_manager.rs

@@ -13,7 +13,7 @@ use crate::{
 use async_stream::stream;
 use futures::stream::StreamExt;
 use lib_infra::future::BoxResultFuture;
-use lib_ot::core::PlainTextAttributes;
+use lib_ot::core::PhantomAttributes;
 use std::{collections::HashMap, fmt::Debug, sync::Arc};
 use tokio::{
     sync::{mpsc, oneshot, RwLock},
@@ -188,7 +188,7 @@ impl ServerFolderManager {
     }
 }
 
-type FolderRevisionSynchronizer = RevisionSynchronizer<PlainTextAttributes>;
+type FolderRevisionSynchronizer = RevisionSynchronizer<PhantomAttributes>;
 
 struct OpenFolderHandler {
     folder_id: String,

shared-lib/flowy-sync/src/server_folder/folder_pad.rs

@@ -1,5 +1,5 @@
 use crate::{entities::folder::FolderDelta, errors::CollaborateError, synchronizer::RevisionSyncObject};
-use lib_ot::core::{OperationTransformable, PlainTextAttributes, PlainTextDelta};
+use lib_ot::core::{OperationTransformable, PhantomAttributes, PlainTextDelta};
 
 pub struct ServerFolder {
     folder_id: String,
@@ -15,7 +15,7 @@ impl ServerFolder {
     }
 }
 
-impl RevisionSyncObject<PlainTextAttributes> for ServerFolder {
+impl RevisionSyncObject<PhantomAttributes> for ServerFolder {
     fn id(&self) -> &str {
         &self.folder_id
     }
@@ -32,7 +32,7 @@ impl RevisionSyncObject<PlainTextAttributes> for ServerFolder {
     }
 
     fn to_json(&self) -> String {
-        self.delta.to_delta_str()
+        self.delta.to_json_str()
     }
 
     fn set_delta(&mut self, new_delta: PlainTextDelta) {

shared-lib/flowy-sync/src/util.rs

@@ -149,7 +149,7 @@ pub fn make_folder_from_revisions_pb(
         folder_delta = folder_delta.compose(&delta)?;
     }
 
-    let text = folder_delta.to_delta_str();
+    let text = folder_delta.to_json_str();
     Ok(Some(FolderInfo {
         folder_id: folder_id.to_string(),
         text,
@@ -183,7 +183,7 @@ pub fn make_document_from_revision_pbs(
         delta = delta.compose(&new_delta)?;
     }
 
-    let text = delta.to_delta_str();
+    let text = delta.to_json_str();
 
     Ok(Some(DocumentPB {
         block_id: doc_id.to_owned(),

shared-lib/lib-ot/src/core/delta/builder.rs

@@ -1,7 +1,7 @@
 use crate::core::delta::{trim, Delta};
-use crate::core::operation::{Attributes, PlainTextAttributes};
+use crate::core::operation::{Attributes, PhantomAttributes};
 
-pub type PlainTextDeltaBuilder = DeltaBuilder<PlainTextAttributes>;
+pub type PlainTextDeltaBuilder = DeltaBuilder<PhantomAttributes>;
 
 /// A builder for creating new [Delta] objects.
 ///

shared-lib/lib-ot/src/core/delta/delta.rs

@@ -3,7 +3,7 @@ use crate::errors::{ErrorBuilder, OTError, OTErrorCode};
 use crate::core::delta::{DeltaIterator, MAX_IV_LEN};
 use crate::core::flowy_str::FlowyStr;
 use crate::core::interval::Interval;
-use crate::core::operation::{Attributes, Operation, OperationBuilder, OperationTransformable, PlainTextAttributes};
+use crate::core::operation::{Attributes, Operation, OperationBuilder, OperationTransformable, PhantomAttributes};
 use bytes::Bytes;
 use serde::de::DeserializeOwned;
 use std::{
@@ -14,12 +14,15 @@ use std::{
     str::FromStr,
 };
 
-pub type PlainTextDelta = Delta<PlainTextAttributes>;
+pub type PlainTextDelta = Delta<PhantomAttributes>;
 
 /// A [Delta] contains list of operations that consists of 'Retain', 'Delete' and 'Insert' operation.
 /// Check out the [Operation] for more details. It describes the document as a sequence of
 /// operations.
 ///
+/// If the [T] supports 'serde', that will enable delta to serialize to JSON or deserialize from
+/// a JSON string.
+///
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct Delta<T: Attributes> {
     pub ops: Vec<Operation<T>>,
@@ -182,7 +185,7 @@ where
     ///         .insert(", AppFlowy")
     ///         .build();
     ///
-    ///  let after_a = delta_a.to_str().unwrap();
+    ///  let after_a = delta_a.content_str().unwrap();
     ///  let after_b = delta_b.apply(&after_a).unwrap();
     ///  assert_eq!("hello, AppFlowy", &after_b);
     /// ```
@@ -565,7 +568,7 @@ impl<T> Delta<T>
 where
     T: Attributes + DeserializeOwned,
 {
-    pub fn from_delta_str(json: &str) -> Result<Self, OTError> {
+    pub fn from_json_str(json: &str) -> Result<Self, OTError> {
         let delta = serde_json::from_str(json).map_err(|e| {
             tracing::trace!("Deserialize failed: {:?}", e);
             tracing::trace!("{:?}", json);
@@ -576,7 +579,7 @@ where
 
     pub fn from_bytes<B: AsRef<[u8]>>(bytes: B) -> Result<Self, OTError> {
         let json = str::from_utf8(bytes.as_ref())?.to_owned();
-        let val = Self::from_delta_str(&json)?;
+        let val = Self::from_json_str(&json)?;
         Ok(val)
     }
 }
@@ -585,16 +588,16 @@ impl<T> Delta<T>
 where
     T: Attributes + serde::Serialize,
 {
-    pub fn to_delta_str(&self) -> String {
+    pub fn to_json_str(&self) -> String {
         serde_json::to_string(self).unwrap_or_else(|_| "".to_owned())
     }
 
-    pub fn to_str(&self) -> Result<String, OTError> {
+    pub fn content_str(&self) -> Result<String, OTError> {
         self.apply("")
     }
 
-    pub fn to_delta_bytes(&self) -> Bytes {
-        let json = self.to_delta_str();
+    pub fn to_json_bytes(&self) -> Bytes {
+        let json = self.to_json_str();
         Bytes::from(json.into_bytes())
     }
 }

shared-lib/lib-ot/src/core/operation/builder.rs

@@ -1,8 +1,8 @@
-use crate::core::operation::{Attributes, Operation, PlainTextAttributes};
+use crate::core::operation::{Attributes, Operation, PhantomAttributes};
 use crate::rich_text::RichTextAttributes;
 
 pub type RichTextOpBuilder = OperationBuilder<RichTextAttributes>;
-pub type PlainTextOpBuilder = OperationBuilder<PlainTextAttributes>;
+pub type PlainTextOpBuilder = OperationBuilder<PhantomAttributes>;
 
 pub struct OperationBuilder<T: Attributes> {
     ty: Operation<T>,

shared-lib/lib-ot/src/core/operation/operation.rs

@@ -26,7 +26,7 @@ pub trait OperationTransformable {
     ///  let document = PlainTextDeltaBuilder::new().build();
     ///  let delta = PlainTextDeltaBuilder::new().insert("abc").build();
     ///  let new_document = document.compose(&delta).unwrap();
-    ///  assert_eq!(new_document.to_str().unwrap(), "abc".to_owned());
+    ///  assert_eq!(new_document.content_str().unwrap(), "abc".to_owned());
     /// ```
     fn compose(&self, other: &Self) -> Result<Self, OTError>
     where
@@ -65,6 +65,12 @@ pub trait OperationTransformable {
     fn invert(&self, other: &Self) -> Self;
 }
 
+/// Each operation can carry attributes. For example, the [RichTextAttributes] has a list of key/value attributes.
+/// Such as { bold: true, italic: true }.  
+///
+/// Because [Operation] is generic over the T, so you must specify the T. For example, the [PlainTextDelta]. It use
+/// use [PhantomAttributes] as the T. [PhantomAttributes] does nothing, just a phantom.
+///
 pub trait Attributes: Default + Display + Eq + PartialEq + Clone + Debug + OperationTransformable {
     fn is_empty(&self) -> bool {
         true
@@ -80,6 +86,14 @@ pub trait Attributes: Default + Display + Eq + PartialEq + Clone + Debug + Opera
     }
 }
 
+/// [Operation] consists of three types.
+/// * Delete
+/// * Retain
+/// * Insert
+///
+/// The [T] should support serde if you want to serialize/deserialize the operation
+/// to json string. You could check out the operation_serde.rs for more information.
+///
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub enum Operation<T: Attributes> {
     Delete(usize),
@@ -241,9 +255,7 @@ where
 
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct Retain<T: Attributes> {
-    // #[serde(rename(serialize = "retain", deserialize = "retain"))]
     pub n: usize,
-    // #[serde(skip_serializing_if = "is_empty")]
     pub attributes: T,
 }
 
@@ -318,10 +330,7 @@ where
 
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct Insert<T: Attributes> {
-    // #[serde(rename(serialize = "insert", deserialize = "insert"))]
     pub s: FlowyStr,
-
-    // #[serde(skip_serializing_if = "is_empty")]
     pub attributes: T,
 }
 
@@ -402,16 +411,16 @@ where
 }
 
 #[derive(Debug, Clone, Eq, PartialEq, Default, Serialize, Deserialize)]
-pub struct PlainTextAttributes();
-impl fmt::Display for PlainTextAttributes {
+pub struct PhantomAttributes();
+impl fmt::Display for PhantomAttributes {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str("PlainAttributes")
+        f.write_str("PhantomAttributes")
     }
 }
 
-impl Attributes for PlainTextAttributes {}
+impl Attributes for PhantomAttributes {}
 
-impl OperationTransformable for PlainTextAttributes {
+impl OperationTransformable for PhantomAttributes {
     fn compose(&self, _other: &Self) -> Result<Self, OTError> {
         Ok(self.clone())
     }