Split State in separate views for Api and CommHandle

- State changes can now be handled differently, depending on whether they were caused locallly (API) or by a remote peer (Comm)
- State functions have more readable names (`write...` and `update...` have similar meanings, but using different names helps readability in the respective (API/Comm) context)

src/api/mod.rs

@@ -3,7 +3,7 @@ use std::sync::Arc;
 use axum::Router;
 use tokio::{net::TcpListener, task::JoinHandle};
 
-use crate::{state::State, config::ApiConfig};
+use crate::{state::{State, ApiState}, config::ApiConfig};
 
 mod v0;
 
@@ -40,11 +40,11 @@ impl From<ApiConfig> for ApiBuilder {
 }
 
 impl ApiBuilder {
-    pub async fn build(&self, state: Arc<State>) -> Api {
+    pub async fn build(&self, state: ApiState) -> Api {
         let mut app: Router = Router::new();
         match &self.version {
-            Some(v) if v == "v0" => app = app.nest(&format!("/{}", v), v0::get_router(state.clone())),
+            Some(v) if v == "v0" => app = app.nest(&format!("/{}", v), v0::get_router(state)),
-            _ => app = app.nest("/v0", v0::get_router(state.clone())),
+            _ => app = app.nest("/v0", v0::get_router(state)),
         }
 
         let ip = match &self.bind_ip {

src/api/v0.rs

@@ -1,44 +1,49 @@
 use std::sync::Arc;
 
 use axum::{Router, routing::{put, get}, extract::{Path, Json}, Extension, response::{IntoResponse, Response}, http::StatusCode};
+use tracing::{warn, debug};
 
-use crate::state::{State, types::{ElementId, ElementContent}};
+use crate::state::{types::{ElementId, ElementContent}, ApiState};
 
 
 
 
-pub fn get_router(state: Arc<State>) -> Router {
+pub fn get_router(state: ApiState) -> Router {
     Router::new()
         .route("/element", put(create_element))
         .route("/element/:id", get(get_element).post(set_element).delete(remove_element))
-        .layer(Extension(state))
+        .layer(Extension(Arc::new(state)))
 }
 
-async fn get_element(Path(id): Path<ElementId>, s: Extension<Arc<State>>) -> Response {
+async fn get_element(Path(id): Path<ElementId>, s: Extension<Arc<ApiState>>) -> Response {
     let element = s.get_element(&id);
     match element {
-        Some(el) => (StatusCode::OK, Json{0: el}).into_response(),
+        Ok(el) => (StatusCode::OK, Json{0: el}).into_response(),
-        None => StatusCode::NOT_FOUND.into_response(),
+        Err(e) => {
+            warn!("Element not found:\n{:?}", e);
+            StatusCode::NOT_FOUND.into_response()
+        }
     }
 }
 
-async fn create_element(s: Extension<Arc<State>>, Json(content): Json<ElementContent>) -> Response {
+async fn create_element(s: Extension<Arc<ApiState>>, Json(content): Json<ElementContent>) -> Response {
     let element_id = s.create_element(&content);
+    debug!("{:?}", element_id);
     match element_id {
         Ok(id) => (StatusCode::OK, Json{0: &Into::<String>::into(&id)}).into_response(),
         Err(_) => StatusCode::INTERNAL_SERVER_ERROR.into_response(),
     }
 }
 
-async fn set_element(Path(id): Path<ElementId>, s: Extension<Arc<State>>, Json(content): Json<ElementContent>) -> Response {
+async fn set_element(Path(id): Path<ElementId>, s: Extension<Arc<ApiState>>, Json(content): Json<ElementContent>) -> Response {
-    let res = s.set_element_content(&id, &content);
+    let res = s.write_element_content(&id, &content);
     match res {
         Ok(_) => StatusCode::OK.into_response(),
         Err(_) => StatusCode::INTERNAL_SERVER_ERROR.into_response(),
     }
 }
 
-async fn remove_element(Path(id): Path<ElementId>, s: Extension<Arc<State>>) -> Response {
+async fn remove_element(Path(id): Path<ElementId>, s: Extension<Arc<ApiState>>) -> Response {
     let res = s.remove_element(&id);
     match res {
         Ok(_) => StatusCode::OK.into_response(),

src/comm/message_processor.rs

@@ -1,24 +1,22 @@
-use std::sync::Arc;
-
 use tracing::debug;
 
-use crate::state::{State, types::PeerId};
+use crate::state::{types::PeerId, CommState};
 
-use super::{messages::{Message, MessageContent}, Peer};
+use super::messages::{Message, MessageContent};
 
 
 
-pub fn handle(state: Arc<State>, peer: &PeerId, message: Message) {
+pub fn handle(state: &CommState, peer: &PeerId, message: Message) {
     debug!("Handling message now: {:?}", message);
     match message.content() {
         MessageContent::Hello { peer_name } => {
-            state.set_peer(&Peer::new(peer.clone(), peer_name.clone())).expect("Couldn't set peer");
+            state.set_peer(peer, peer_name).expect("State failed");
         },
         MessageContent::CreateElement { id, content } => {
-            state.set_element(id, content).expect("State failed");
+            state.add_received_element(id, content, message.id()).expect("State failed");
         },
         MessageContent::SetElement { id, content } => {
-            state.set_element(id, content).expect("State failed");
+            state.update_element_content(id, content, message.id()).expect("State failed");
         },
         MessageContent::RemoveElement { id } => {
             state.remove_element(id).expect("State failed");

src/comm/mod.rs

@@ -5,6 +5,7 @@ use tracing::{warn, error, debug};
 pub use types::*;
 
 use std::collections::HashMap;
+use std::ops::Deref;
 use std::sync::Arc;
 use std::io::{Read, Write};
 
@@ -15,13 +16,13 @@ use tokio::sync::RwLock;
 use tokio::task::JoinHandle;
 
 use crate::Config;
-use crate::state::State;
+use crate::state::CommState;
 use crate::state::types::PeerId;
 
 use self::messages::Message;
 
 pub struct CommHandle {
-    state: Arc<State>,
+    state: Arc<CommState>,
     i2p_server: Arc<I2pListener>,
     // Maps peer addresses to existing connections to them
     clients: Arc<RwLock<HashMap<I2pSocketAddr, Arc<RwLock<I2pStream>>>>>,
@@ -29,7 +30,7 @@ pub struct CommHandle {
 }
 
 impl CommHandle {
-    pub fn new(state: Arc<State>, config: &Config) -> anyhow::Result<Self> {
+    pub fn new(state: CommState, config: &Config) -> anyhow::Result<Self> {
         let mut listener_builder = I2pListenerBuilder::default()
             .with_options(SAMOptions::default());
 
@@ -42,7 +43,7 @@ impl CommHandle {
         .unwrap();
 
         Ok(CommHandle {
-            state: state,
+            state: Arc::new(state),
             i2p_server: Arc::new(listener),
             clients: Default::default(),
             thread: RwLock::new(None),
@@ -155,7 +156,7 @@ impl CommHandle {
         Ok(i2p_dest)
     }
 
-    fn read_connection(wrapped_stream: Arc<RwLock<I2pStream>>, state: Arc<State>) -> JoinHandle<()> {
+    fn read_connection(wrapped_stream: Arc<RwLock<I2pStream>>, state: Arc<CommState>) -> JoinHandle<()> {
         tokio::spawn(async move {
             let mut stream = wrapped_stream.write().await;
             let peer: PeerId = stream.peer_addr().expect("Failed to get peer addr").into();
@@ -172,7 +173,7 @@ impl CommHandle {
                     Ok(value) => {
                         match serde_json::from_value::<Message>(value) {
                             Ok(message) => {
-                                message_processor::handle(state.clone(), &peer, message);
+                                message_processor::handle(state.deref(), &peer, message);
                             },
                             Err(e) => warn!("Deserialization failed: {:?}", e),
                         }
@@ -200,14 +201,14 @@ mod tests {
     use i2p::sam_options::SAMOptions;
 
     use crate::Config;
-    use crate::state::State;
+    use crate::state::{State, CommState};
     use crate::comm::{messages, Message};
     use crate::state::types::ElementId;
 
     use super::CommHandle;
     #[tokio::test(flavor = "multi_thread")]
     pub async fn msg() {
-        let ch = CommHandle::new(State::new().await.unwrap(), &Config::default() ).unwrap();
+        let ch = CommHandle::new(CommState::new(State::new().await.unwrap()), &Config::default() ).unwrap();
         ch.run().await;
         println!("My address: {:?}", ch.i2p_b32_address());
         

src/lib.rs

@@ -6,7 +6,7 @@ use comm::{CommHandle, Peer};
 use config::Config;
 use i2p::net::I2pSocketAddr;
 use serde::{Serialize, Deserialize};
-use state::{State, types::{ElementContent, ElementId, MessageId, PeerId}};
+use state::{State, types::{ElementContent, ElementId, MessageId, PeerId}, CommState, ApiState};
 
 mod api;
 pub mod comm;
@@ -28,10 +28,10 @@ pub struct Ubisync {
 impl Ubisync {
     pub async fn new(config: &Config) -> anyhow::Result<Self> {
         let state = State::new().await?;
-        let comm_handle = Arc::new(CommHandle::new(state.clone(), config)?);
+        let comm_handle = Arc::new(CommHandle::new(CommState::new(state.clone()), config)?);
         state.set_comm_handle(comm_handle.clone());
 
-        let api = Arc::new(ApiBuilder::from(config.api_config.clone()).build(state.clone()).await);
+        let api = Arc::new(ApiBuilder::from(config.api_config.clone()).build(ApiState::new(state.clone())).await);
 
         comm_handle.run().await;
         Ok(Ubisync {
@@ -64,10 +64,6 @@ impl Ubisync {
     pub fn get_destination(&self) -> anyhow::Result<I2pSocketAddr> {
         self.comm_handle.i2p_address()
     }
-
-    pub fn create_element(&self, content: &ElementContent) -> anyhow::Result<ElementId> {
-        self.state_handle.create_element(content)
-    }
 }
 
 

src/state/api_state.rs

@@ -0,0 +1,86 @@
+use std::sync::Arc;
+
+use cozo::DbInstance;
+use tracing::debug;
+
+use crate::{state::{types::ElementId, queries}, comm::messages::MessageContent};
+
+use super::{State, types::{ElementContent, Element}};
+
+
+
+pub struct ApiState {
+    state: Arc<State>,
+}
+
+impl ApiState {
+    pub fn new(state: Arc<State>) -> Self {
+        ApiState { state: state }
+    }
+
+    pub fn create_element(&self, content: &ElementContent) -> anyhow::Result<ElementId> {
+        let id = ElementId::new();
+        queries::elements::add(self.db(), &id, &content, None, true)?;
+        debug!("Added element {{{}}}", &id.to_string());
+
+        self.state.send_to_peers(MessageContent::CreateElement { id: id.clone(), content: content.clone() });
+        Ok(id)
+    }
+
+    pub fn write_element_content(&self, id: &ElementId, content: &ElementContent) -> anyhow::Result<()> {
+        queries::elements::set_content(self.db(), id, content)?;
+        queries::elements::set_local_changes(self.db(), id, true)?;
+        debug!("Wrote element content {{{}}}", &id.to_string());
+
+        Ok(())
+    }
+
+    pub fn remove_element(&self, id: &ElementId) -> anyhow::Result<()> {
+        let res = self.state.remove_element(id);
+        debug!("Removed element {{{}}}", &id.to_string());
+
+        res
+    }
+
+    pub fn get_element(&self, id: &ElementId) -> anyhow::Result<Element> {
+        self.state.get_element(id)
+    }
+
+
+    fn db(&self) -> &DbInstance {
+        &self.state.db
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::ApiState;
+    use crate::state::{types::ElementContent, State};
+    
+    #[tokio::test]
+    #[serial_test::serial]
+    async fn test_element_create() {
+        tracing_subscriber::fmt().pretty().init();
+        let state = ApiState::new(State::new().await.unwrap());
+        let id = state.create_element(&ElementContent::Text("Test-text".to_string())).unwrap();
+        let el = state.get_element(&id).unwrap();
+        assert_eq!(
+            ElementContent::Text("Test-text".to_string()),
+            el.content().to_owned()
+        )
+    }
+
+    #[tokio::test]
+    #[serial_test::serial]
+    async fn test_element_write() {
+        tracing_subscriber::fmt().pretty().init();
+        let state = ApiState::new(State::new().await.unwrap());
+        let id = state.create_element(&ElementContent::Text("Test-text".to_string())).unwrap();
+        state.write_element_content(&id,&ElementContent::Text("Test-text 2".to_string())).unwrap();
+        let el = state.get_element(&id).unwrap();
+        assert_eq!(
+            ElementContent::Text("Test-text 2".to_string()),
+            el.content().to_owned()
+        )
+    }
+}

src/state/comm_state.rs

@@ -0,0 +1,98 @@
+use std::sync::Arc;
+
+use cozo::DbInstance;
+use tracing::debug;
+
+use crate::{state::queries, comm::Peer};
+
+use super::{State, types::{MessageId, ElementContent, ElementId, PeerId, Element}};
+
+
+//TODO: Notify API about changes
+pub struct CommState {
+    state: Arc<State>
+}
+
+impl CommState {
+    pub fn new(state: Arc<State>) -> Self {
+        CommState { state: state }
+    }
+    
+    pub fn add_received_element(&self, id: &ElementId, content: &ElementContent, latest_message: &MessageId) -> anyhow::Result<()> {
+        queries::elements::add(self.db(), &id, &content, Some(latest_message.to_owned()), false)?;
+        debug!("Added element {{{}}}", &id.to_string());
+
+        Ok(())
+    }
+
+    pub fn update_element_content(&self, id: &ElementId, content: &ElementContent, latest_message: &MessageId) -> anyhow::Result<()> {
+        //TODO: resolve potential conflicts with local changes
+        queries::elements::set_content(self.db(), id, content)?;
+        queries::elements::set_latest_message(self.db(), id, Some(latest_message.to_owned()))?;
+        debug!("Updated element {{{}}}", &id.to_string());
+
+        Ok(())
+    }
+
+    pub fn remove_element(&self, id: &ElementId) -> anyhow::Result<()> {
+        let res = self.state.remove_element(id);
+        debug!("Removed element {{{}}}", &id.to_string());
+
+        res
+    }
+
+    pub fn get_element(&self, id: &ElementId) -> anyhow::Result<Element> {
+        self.state.get_element(id)
+    }
+
+    pub fn set_peer(&self, id: &PeerId, name: &str) -> anyhow::Result<()> {
+        queries::peers::put(self.db(), id, name)?;
+        debug!("Set peer {{{}}}", id.to_string());
+        
+        Ok(())
+    }
+
+    pub fn get_peers(&self) -> anyhow::Result<Vec<Peer>> {
+        self.state.get_peers()
+    }
+
+
+    fn db(&self) -> &DbInstance {
+        &self.state.db
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::CommState;
+    use crate::state::{types::{ElementContent, ElementId, MessageId}, State};
+    
+    #[tokio::test]
+    #[serial_test::serial]
+    async fn test_element_add() {
+        tracing_subscriber::fmt().pretty().init();
+        let state = CommState::new(State::new().await.unwrap());
+        let id = ElementId::new();
+        state.add_received_element(&id, &ElementContent::Text("Test-text".to_string()), &MessageId::new()).unwrap();
+        let el = state.get_element(&id).unwrap();
+        assert_eq!(
+            ElementContent::Text("Test-text".to_string()),
+            el.content().to_owned()
+        )
+    }
+
+    #[tokio::test]
+    #[serial_test::serial]
+    async fn test_element_update() {
+        tracing_subscriber::fmt().pretty().init();
+        let state = CommState::new(State::new().await.unwrap());
+        let id = ElementId::new();
+        state.add_received_element(&id, &ElementContent::Text("Test-text".to_string()), &MessageId::new()).unwrap();
+        state.update_element_content(&id,&ElementContent::Text("Test-text 2".to_string()), &MessageId::new()).unwrap();
+        let el = state.get_element(&id).unwrap();
+        assert_eq!(
+            ElementContent::Text("Test-text 2".to_string()),
+            el.content().to_owned()
+        )
+    }
+}

src/state/mod.rs

@@ -10,9 +10,14 @@ use self::types::{ElementContent, ElementId, Element, Tag};
 
 pub mod types;
 
+mod api_state;
+mod comm_state;
 mod queries;
 mod schema;
 
+pub use api_state::ApiState;
+pub use comm_state::CommState;
+
 pub struct State {
     db: DbInstance,
     comm_handle: RwLock<Option<Arc<CommHandle>>>,
@@ -34,58 +39,37 @@ impl State {
         *self.comm_handle.write().as_deref_mut().expect("Could not set state's CommHandle") = Some(handle);
     }
 
-
-    // Create an element and add it to the database
-    pub fn create_element(&self, content: &ElementContent) -> anyhow::Result<ElementId> {
-        let id = ElementId::new();
-        queries::set_element(&self.db, &id, &content)?;
-        debug!("Created element with id {:?}: {:?}", &id, self.get_element(&id));
-
-        self.send_to_peers(MessageContent::CreateElement { id: id.clone(), content: content.clone() });
-        Ok(id)
-    }
-
-    // Anyone updated an element, update it in the database 
-    pub fn set_element(&self, element_id: &ElementId, content: &ElementContent) -> anyhow::Result<()> {
-        let res = queries::set_element(&self.db, element_id, content);
-        debug!("Set element with id {:?}: {:?}", element_id, self.get_element(element_id));
-        
-        self.send_to_peers(MessageContent::SetElement { id: element_id.clone(), content: content.clone() });
-        res
-    }
-
     pub fn set_element_content(&self, element_id: &ElementId, content: &ElementContent) -> anyhow::Result<()> {
-        let res = queries::set_element_content(&self.db, element_id, content);
+        let res = queries::elements::set_content(&self.db, element_id, content);
-        debug!("Set element content with id {:?}: {:?}", element_id, self.get_element(element_id));
+        debug!("Set content of element with id {:?}: {:?}", element_id, self.get_element(element_id));
-        
         
         self.send_to_peers(MessageContent::SetElement { id: element_id.clone(), content: content.clone() });
         res
     }
 
     pub fn remove_element(&self, element_id: &ElementId) -> anyhow::Result<()> {
-        let res = queries::remove_element(&self.db, element_id);
+        let res = queries::elements::remove(&self.db, element_id);
 
         self.send_to_peers(MessageContent::RemoveElement { id: element_id.clone() });
         res
     }
 
-    pub fn get_element(&self, id: &ElementId) -> Option<Element> {
+    pub fn get_element(&self, id: &ElementId) -> anyhow::Result<Element> {
-        queries::get_element(&self.db, id).ok()
+        queries::elements::get(&self.db, id)
     }
 
     pub fn get_elements_by_tag(&self, tag: &Tag) -> Vec<ElementId> {
-        queries::get_elements_by_tag(&self.db, tag)
+        queries::elements::get_by_tag(&self.db, tag)
         .map_err(|e| {error!("{}", e); e})
         .unwrap_or(vec![])
     }
 
     pub fn set_peer(&self, peer: &Peer) -> anyhow::Result<()> {
-        queries::add_peer(&self.db, &peer.id(), &peer.name())
+        queries::peers::put(&self.db, &peer.id(), &peer.name())
     }
 
     pub fn get_peers(&self) -> anyhow::Result<Vec<Peer>> {
-        queries::get_peers(&self.db)
+        queries::peers::get(&self.db)
     }
 
 
@@ -104,37 +88,3 @@ impl State {
         }
     }
 }
-
-
-#[cfg(test)]
-mod tests {
-    use crate::state::State;
-    use crate::state::types::ElementContent;
-    
-    #[tokio::test]
-    #[serial_test::serial]
-    async fn test_create() {
-        tracing_subscriber::fmt().pretty().init();
-        let state = State::new().await.unwrap();
-        let id = state.create_element(&ElementContent::Text("Test-text".to_string())).unwrap();
-        let el = state.get_element(&id).unwrap();
-        assert_eq!(
-            ElementContent::Text("Test-text".to_string()),
-            el.content().to_owned()
-        )
-    }
-
-    #[tokio::test]
-    #[serial_test::serial]
-    async fn test_update() {
-        tracing_subscriber::fmt().pretty().init();
-        let state = State::new().await.unwrap();
-        let id = state.create_element(&ElementContent::Text("Test-text".to_string())).unwrap();
-        state.set_element(&id,&ElementContent::Text("Test-text 2".to_string())).unwrap();
-        let el = state.get_element(&id).unwrap();
-        assert_eq!(
-            ElementContent::Text("Test-text 2".to_string()),
-            el.content().to_owned()
-        )
-    }
-}

src/state/queries/elements.rs

@@ -3,65 +3,82 @@ use std::collections::BTreeMap;
 use anyhow::{Error, bail};
 use cozo::{DbInstance, DataValue, JsonData, ScriptMutability};
 use serde_json::Value;
-use tracing::error;
+use tracing::{error, debug};
 
-use crate::{state::{ElementContent, ElementId, Element, types::Tag}, run_query};
+use crate::{state::{ElementContent, ElementId, Element, types::{Tag, MessageId}}, run_query};
 
-pub fn set_element(db: &DbInstance, id: &ElementId, content: &ElementContent) -> anyhow::Result<()> {
+pub fn add(db: &DbInstance, id: &ElementId, content: &ElementContent, latest_message: Option<MessageId>, local_changes: bool) -> anyhow::Result<()> {
     let params = vec![
         ("id", DataValue::Str(serde_json::to_string(&id)?.into())),
-        ("content", DataValue::Str(serde_json::to_string(content)?.into()))
+        ("content", DataValue::Json(JsonData(serde_json::to_value(content)?))),
+        ("latest_message", match latest_message {
+            Some(m) => DataValue::Str(serde_json::to_string(&m)?.into()),
+            None => DataValue::Null,
+        }),
+        ("local_changes", DataValue::Bool(local_changes)),
     ];
 
-    match run_query!(&db, ":put elements {id => content}", params, ScriptMutability::Mutable) {
+    match run_query!(&db, ":insert elements {id => content, latest_message, local_changes}", params, ScriptMutability::Mutable) {
         Ok(_) => Ok(()),
         Err(report) => bail!(report),
     }
 }
 
-pub fn set_element_content(db: &DbInstance, id: &ElementId, content: &ElementContent) -> anyhow::Result<()> {
+pub fn set_content(db: &DbInstance, id: &ElementId, content: &ElementContent) -> anyhow::Result<()> {
-    let params = vec![
+    set_property(db, id, "content", DataValue::Json(JsonData(serde_json::to_value(content)?)))
-        ("id", DataValue::Str(serde_json::to_string(&id)?.into())),
-        ("content", DataValue::Str(serde_json::to_string(content)?.into()))
-    ];
-
-    match run_query!(&db, ":put elements {id => content}", params, ScriptMutability::Mutable) {
-        Ok(_) => Ok(()),
-        Err(report) => bail!(report),
-    }
 }
 
-pub fn remove_element(db: &DbInstance, id: &ElementId) -> anyhow::Result<()> {
+pub fn set_latest_message(db: &DbInstance, id: &ElementId, latest_message: Option<MessageId>) -> anyhow::Result<()> {
+    set_property(db, id, "latest_message", match latest_message {
+        Some(m) => DataValue::Str(serde_json::to_string(&m)?.into()),
+        None => DataValue::Null,
+    })
+}
+
+pub fn set_local_changes(db: &DbInstance, id: &ElementId, local_changes: bool) -> anyhow::Result<()> {
+    set_property(db, id, "local_changes", DataValue::Bool(local_changes))
+}
+
+pub fn remove(db: &DbInstance, id: &ElementId) -> anyhow::Result<()> {
     match run_query!(&db, ":delete elements {id}", vec![("id", DataValue::Str(serde_json::to_string(&id)?.into()))], cozo::ScriptMutability::Mutable) {
         Ok(_) => Ok(()),
         Err(report) => bail!(report),
     }
 }
 
-pub fn get_element(db: &DbInstance, id: &ElementId) -> anyhow::Result<Element> {
+pub fn get(db: &DbInstance, id: &ElementId) -> anyhow::Result<Element> {
     let mut params = BTreeMap::new();
     params.insert("id".to_string(), DataValue::Str(serde_json::to_string(&id)?.into()));
 
     let result = db.run_script("
-    ?[content] := *elements[$id, content]
+    ?[content, latest_message, local_changes] := *elements[$id, content, latest_message, local_changes]
     ", params, cozo::ScriptMutability::Immutable);
     match result {
         Ok(val) => {
             if let Some(firstrow) = val.rows.first() {
-                if let [ DataValue::Json(JsonData(Value::String(content))) ] = firstrow.as_slice() {
+                debug!("db result: {:?}", &firstrow.as_slice());
-                    return Ok(Element::new(
+                if let [ DataValue::Json(JsonData(content)), latest_message, DataValue::Bool(local_changes) ] = firstrow.as_slice() {
+                    return Ok(Element::from((
                         id.to_owned(),
-                        content.as_str().try_into()?,
+                        serde_json::from_value(content.to_owned())?,
-                    ));
+                        match latest_message {
+                            DataValue::Str(s) => Some(serde_json::from_str(s)?),
+                            _ => None,
+                        },
+                        local_changes.to_owned()
+                    )));
                 }
+                return Err(Error::msg("Could not parse db result as Element"));
+            }
+            else {
+                return Err(Error::msg("No rows returned for element query"))
             }
-            return Err(Error::msg("Could not parse db result as Element"));
         },
         Err(report) => bail!(report),
     }
 }
 
-pub fn get_elements_by_tag(db: &DbInstance, tag: &Tag) -> anyhow::Result<Vec<ElementId>> {
+pub fn get_by_tag(db: &DbInstance, tag: &Tag) -> anyhow::Result<Vec<ElementId>> {
     let mut params = BTreeMap::new();
     params.insert("tag".to_string(), DataValue::Str(serde_json::to_string(tag)?.into()));
 
@@ -88,3 +105,16 @@ pub fn get_elements_by_tag(db: &DbInstance, tag: &Tag) -> anyhow::Result<Vec<Ele
         Err(report) => bail!(report),
     }
 }
+
+
+fn set_property(db: &DbInstance, id: &ElementId, key: &str, value: DataValue) -> anyhow::Result<()> {
+    let params = vec![
+        ("id", DataValue::Str(serde_json::to_string(id)?.into())),
+        (key, value)
+    ];
+
+    match run_query!(&db, format!(":update elements {{id => {key}}}"), params, ScriptMutability::Mutable) {
+        Ok(_) => Ok(()),
+        Err(report) => bail!(report),
+    }
+}

src/state/queries/mod.rs

@@ -1,9 +1,6 @@
-mod elements;
+pub mod elements;
 
-pub use elements::*;
+pub mod peers;
-
-mod peers;
-pub use peers::*;
 
 
 #[macro_export]

src/state/queries/peers.rs

@@ -7,7 +7,7 @@ use crate::{state::types::PeerId, comm::Peer, run_query};
 
 
 
-pub fn add_peer(db: &DbInstance, id: &PeerId, name: &str) -> anyhow::Result<()> {
+pub fn put(db: &DbInstance, id: &PeerId, name: &str) -> anyhow::Result<()> {
     let params = vec![
         ("id", DataValue::Str(serde_json::to_string(id)?.into())),
         ("name", DataValue::Str(serde_json::to_string(name)?.into()))
@@ -19,7 +19,7 @@ pub fn add_peer(db: &DbInstance, id: &PeerId, name: &str) -> anyhow::Result<()>
     }
 }
 
-pub fn get_peers(db: &DbInstance) -> anyhow::Result<Vec<Peer>> {
+pub fn get(db: &DbInstance) -> anyhow::Result<Vec<Peer>> {
     let result = db.run_script("
     ?[id, name] := *peers{id, name}
     ", Default::default(), cozo::ScriptMutability::Immutable);

src/state/schema.rs

@@ -17,10 +17,12 @@ pub fn add_schema(db: &DbInstance) -> anyhow::Result<()> {
         id: String,
         =>
         content: Json,
+        latest_message: String?,
+        local_changes: Bool,
     }}
     {:create tags {
         tag: String,
-        element: String
+        element: String,
     }}
     ", params, cozo::ScriptMutability::Mutable) {
         Ok(_) => Ok(()),

src/state/types/element.rs

@@ -1,6 +1,6 @@
 use serde::{Serialize, Deserialize};
 
-use super::{ElementId, ElementContent};
+use super::{ElementId, ElementContent, MessageId};
 
 
 
@@ -8,12 +8,21 @@ use super::{ElementId, ElementContent};
 pub struct Element {
     // Uuid identifying the element itself
     id: ElementId,
-    content: ElementContent
+    content: ElementContent,
+    latest_message: Option<MessageId>,
+    local_changes: bool,
+}
+
+impl From<(ElementId, ElementContent, Option<MessageId>, bool)> for Element {
+    fn from(value: (ElementId, ElementContent, Option<MessageId>, bool)) -> Self {
+        Element { id: value.0, content: value.1, latest_message: value.2, local_changes: value.3 }
+    }
 }
 
 impl Element {
     pub fn new(id: ElementId, content: ElementContent) -> Self {
-        Element { id: id, content: content }
+        // A new element with no latest message must have local changes
+        Element { id: id, content: content, latest_message: None, local_changes: true }
     }
 
     pub fn id(&self) -> &ElementId {

src/state/types/element_id.rs

@@ -9,6 +9,12 @@ impl ElementId {
     }
 }
 
+impl ToString for ElementId {
+    fn to_string(&self) -> String {
+        self.0.to_string()
+    }
+}
+
 impl From<&ElementId> for String {
     fn from(value: &ElementId) -> Self {
         value.0.to_string()

src/state/types/peer_id.rs

@@ -14,6 +14,12 @@ impl PeerId {
     }
 }
 
+impl ToString for PeerId {
+    fn to_string(&self) -> String {
+        self.i2p_addr.to_string()
+    }
+}
+
 impl TryFrom<&str> for PeerId {
     type Error = anyhow::Error;
 

tests/api.rs

@@ -19,12 +19,16 @@ async fn two_nodes_element_creation() {
     let test_element_content = ElementContent::Text("Text".to_string());
     let put_resp = http_client.put(&format!("http://localhost:9981/v0/element")).json(&test_element_content).send().await.unwrap();
     debug!("{:?}", &put_resp);
-    let id = serde_json::from_str::<ElementId>(&put_resp.text().await.expect("No put response body")).expect("Could not deserialize ElementId");
+    let put_resp_text = put_resp.text().await.expect("No put response body");
+    debug!("{}", put_resp_text);
+    let id = serde_json::from_str::<ElementId>(&put_resp_text).expect("Could not deserialize ElementId");
 
     tokio::time::sleep(Duration::from_millis(3000)).await;
     
     let get_resp = http_client.get(&format!("http://localhost:9982/v0/element/{}", Into::<String>::into(&id))).send().await.expect("Get request failed");
-    let received_element = serde_json::from_str::<Element>(&get_resp.text().await.expect("No get request body")).expect("Could not deserialize Element");
+    let get_resp_text = get_resp.text().await.expect("No get request body");
+    debug!("{}", get_resp_text);
+    let received_element = serde_json::from_str::<Element>(&get_resp_text).expect("Could not deserialize Element");
     debug!("Other node received this element: {:?}", received_element);
     
     assert_eq!(&test_element_content, received_element.content());