lemmy/server/src/websocket/server.rs

720 lines
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Rust
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//! `ChatServer` is an actor. It maintains list of connection client session.
//! And manages available rooms. Peers send messages to other peers in same
//! room through `ChatServer`.
use actix::prelude::*;
use diesel::r2d2::{ConnectionManager, Pool, PooledConnection};
use diesel::PgConnection;
use failure::Error;
use rand::{rngs::ThreadRng, Rng};
use serde::{Deserialize, Serialize};
use serde_json::Value;
use std::collections::{HashMap, HashSet};
use std::str::FromStr;
use std::time::SystemTime;
use strum::IntoEnumIterator;
use crate::api::comment::*;
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use crate::api::community::*;
use crate::api::post::*;
use crate::api::site::*;
use crate::api::user::*;
use crate::api::*;
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use crate::websocket::UserOperation;
use crate::Settings;
type ConnectionId = usize;
type PostId = i32;
type CommunityId = i32;
type UserId = i32;
type IPAddr = String;
/// Chat server sends this messages to session
#[derive(Message)]
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#[rtype(result = "()")]
pub struct WSMessage(pub String);
/// Message for chat server communications
/// New chat session is created
#[derive(Message)]
#[rtype(usize)]
pub struct Connect {
pub addr: Recipient<WSMessage>,
pub ip: IPAddr,
}
/// Session is disconnected
#[derive(Message)]
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#[rtype(result = "()")]
pub struct Disconnect {
pub id: ConnectionId,
pub ip: IPAddr,
}
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#[derive(Serialize, Deserialize, Message)]
#[rtype(String)]
pub struct StandardMessage {
/// Id of the client session
pub id: ConnectionId,
/// Peer message
pub msg: String,
}
#[derive(Debug)]
pub struct RateLimitBucket {
last_checked: SystemTime,
allowance: f64,
}
pub struct SessionInfo {
pub addr: Recipient<WSMessage>,
pub ip: IPAddr,
}
#[derive(Eq, PartialEq, Hash, Debug, EnumIter, Copy, Clone)]
pub enum RateLimitType {
Message,
Register,
Post,
}
/// `ChatServer` manages chat rooms and responsible for coordinating chat
/// session.
pub struct ChatServer {
/// A map from generated random ID to session addr
sessions: HashMap<ConnectionId, SessionInfo>,
/// A map from post_id to set of connectionIDs
post_rooms: HashMap<PostId, HashSet<ConnectionId>>,
/// A map from community to set of connectionIDs
community_rooms: HashMap<CommunityId, HashSet<ConnectionId>>,
/// A map from user id to its connection ID for joined users. Remember a user can have multiple
/// sessions (IE clients)
user_rooms: HashMap<UserId, HashSet<ConnectionId>>,
/// Rate limiting based on rate type and IP addr
rate_limit_buckets: HashMap<RateLimitType, HashMap<IPAddr, RateLimitBucket>>,
rng: ThreadRng,
db: Pool<ConnectionManager<PgConnection>>,
}
impl ChatServer {
pub fn startup(db: Pool<ConnectionManager<PgConnection>>) -> ChatServer {
ChatServer {
sessions: HashMap::new(),
rate_limit_buckets: HashMap::new(),
post_rooms: HashMap::new(),
community_rooms: HashMap::new(),
user_rooms: HashMap::new(),
rng: rand::thread_rng(),
db,
}
}
fn join_community_room(&mut self, community_id: CommunityId, id: ConnectionId) {
// remove session from all rooms
for sessions in self.community_rooms.values_mut() {
sessions.remove(&id);
}
// If the room doesn't exist yet
if self.community_rooms.get_mut(&community_id).is_none() {
self.community_rooms.insert(community_id, HashSet::new());
}
self
.community_rooms
.get_mut(&community_id)
.unwrap()
.insert(id);
}
fn join_post_room(&mut self, post_id: PostId, id: ConnectionId) {
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// remove session from all rooms
for sessions in self.post_rooms.values_mut() {
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sessions.remove(&id);
}
// If the room doesn't exist yet
if self.post_rooms.get_mut(&post_id).is_none() {
self.post_rooms.insert(post_id, HashSet::new());
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}
self.post_rooms.get_mut(&post_id).unwrap().insert(id);
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}
fn join_user_room(&mut self, user_id: UserId, id: ConnectionId) {
// remove session from all rooms
for sessions in self.user_rooms.values_mut() {
sessions.remove(&id);
}
// If the room doesn't exist yet
if self.user_rooms.get_mut(&user_id).is_none() {
self.user_rooms.insert(user_id, HashSet::new());
}
self.user_rooms.get_mut(&user_id).unwrap().insert(id);
}
fn send_post_room_message(&self, post_id: PostId, message: &str, skip_id: ConnectionId) {
if let Some(sessions) = self.post_rooms.get(&post_id) {
for id in sessions {
if *id != skip_id {
if let Some(info) = self.sessions.get(id) {
let _ = info.addr.do_send(WSMessage(message.to_owned()));
}
}
}
}
}
fn send_community_room_message(
&self,
community_id: CommunityId,
message: &str,
skip_id: ConnectionId,
) {
if let Some(sessions) = self.community_rooms.get(&community_id) {
for id in sessions {
if *id != skip_id {
if let Some(info) = self.sessions.get(id) {
let _ = info.addr.do_send(WSMessage(message.to_owned()));
}
}
}
}
}
fn send_user_room_message(&self, user_id: UserId, message: &str, skip_id: ConnectionId) {
if let Some(sessions) = self.user_rooms.get(&user_id) {
for id in sessions {
if *id != skip_id {
if let Some(info) = self.sessions.get(id) {
let _ = info.addr.do_send(WSMessage(message.to_owned()));
}
}
}
}
}
fn send_all_message(&self, message: &str, skip_id: ConnectionId) {
for id in self.sessions.keys() {
if *id != skip_id {
if let Some(info) = self.sessions.get(id) {
let _ = info.addr.do_send(WSMessage(message.to_owned()));
}
}
}
}
fn comment_sends(
&self,
user_operation: UserOperation,
comment: CommentResponse,
id: ConnectionId,
) -> Result<String, Error> {
let mut comment_reply_sent = comment.clone();
comment_reply_sent.comment.my_vote = None;
comment_reply_sent.comment.user_id = None;
// For the post room ones, and the directs back to the user
// strip out the recipient_ids, so that
// users don't get double notifs
let mut comment_user_sent = comment.clone();
comment_user_sent.recipient_ids = Vec::new();
let mut comment_post_sent = comment_reply_sent.clone();
comment_post_sent.recipient_ids = Vec::new();
let comment_reply_sent_str = to_json_string(&user_operation, &comment_reply_sent)?;
let comment_post_sent_str = to_json_string(&user_operation, &comment_post_sent)?;
let comment_user_sent_str = to_json_string(&user_operation, &comment_user_sent)?;
// Send it to the post room
self.send_post_room_message(comment.comment.post_id, &comment_post_sent_str, id);
// Send it to the recipient(s) including the mentioned users
for recipient_id in comment_reply_sent.recipient_ids {
self.send_user_room_message(recipient_id, &comment_reply_sent_str, id);
}
Ok(comment_user_sent_str)
}
fn post_sends(
&self,
user_operation: UserOperation,
post: PostResponse,
id: ConnectionId,
) -> Result<String, Error> {
let community_id = post.post.community_id;
// Don't send my data with it
let mut post_sent = post.clone();
post_sent.post.my_vote = None;
post_sent.post.user_id = None;
let post_sent_str = to_json_string(&user_operation, &post_sent)?;
// Send it to /c/all and that community
self.send_community_room_message(0, &post_sent_str, id);
self.send_community_room_message(community_id, &post_sent_str, id);
to_json_string(&user_operation, post)
}
fn check_rate_limit_register(&mut self, id: usize, check_only: bool) -> Result<(), Error> {
self.check_rate_limit_full(
RateLimitType::Register,
id,
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Settings::get().rate_limit.register,
Settings::get().rate_limit.register_per_second,
check_only,
)
}
fn check_rate_limit_post(&mut self, id: usize, check_only: bool) -> Result<(), Error> {
self.check_rate_limit_full(
RateLimitType::Post,
id,
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Settings::get().rate_limit.post,
Settings::get().rate_limit.post_per_second,
check_only,
)
}
fn check_rate_limit_message(&mut self, id: usize, check_only: bool) -> Result<(), Error> {
self.check_rate_limit_full(
RateLimitType::Message,
id,
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Settings::get().rate_limit.message,
Settings::get().rate_limit.message_per_second,
check_only,
)
}
#[allow(clippy::float_cmp)]
fn check_rate_limit_full(
&mut self,
type_: RateLimitType,
id: usize,
rate: i32,
per: i32,
check_only: bool,
) -> Result<(), Error> {
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if let Some(info) = self.sessions.get(&id) {
if let Some(bucket) = self.rate_limit_buckets.get_mut(&type_) {
if let Some(rate_limit) = bucket.get_mut(&info.ip) {
let current = SystemTime::now();
let time_passed = current.duration_since(rate_limit.last_checked)?.as_secs() as f64;
// The initial value
if rate_limit.allowance == -2f64 {
rate_limit.allowance = rate as f64;
};
rate_limit.last_checked = current;
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rate_limit.allowance += time_passed * (rate as f64 / per as f64);
if !check_only && rate_limit.allowance > rate as f64 {
rate_limit.allowance = rate as f64;
}
if rate_limit.allowance < 1.0 {
println!(
"Rate limited IP: {}, time_passed: {}, allowance: {}",
&info.ip, time_passed, rate_limit.allowance
);
Err(
APIError {
message: format!("Too many requests. {} per {} seconds", rate, per),
}
.into(),
)
} else {
if !check_only {
rate_limit.allowance -= 1.0;
}
Ok(())
}
} else {
Ok(())
}
} else {
Ok(())
}
} else {
Ok(())
}
}
}
/// Make actor from `ChatServer`
impl Actor for ChatServer {
/// We are going to use simple Context, we just need ability to communicate
/// with other actors.
type Context = Context<Self>;
}
/// Handler for Connect message.
///
/// Register new session and assign unique id to this session
impl Handler<Connect> for ChatServer {
type Result = usize;
fn handle(&mut self, msg: Connect, _ctx: &mut Context<Self>) -> Self::Result {
// register session with random id
let id = self.rng.gen::<usize>();
println!("{} joined", &msg.ip);
self.sessions.insert(
id,
SessionInfo {
addr: msg.addr,
ip: msg.ip.to_owned(),
},
);
for rate_limit_type in RateLimitType::iter() {
if self.rate_limit_buckets.get(&rate_limit_type).is_none() {
self
.rate_limit_buckets
.insert(rate_limit_type, HashMap::new());
}
if let Some(bucket) = self.rate_limit_buckets.get_mut(&rate_limit_type) {
if bucket.get(&msg.ip).is_none() {
bucket.insert(
msg.ip.to_owned(),
RateLimitBucket {
last_checked: SystemTime::now(),
allowance: -2f64,
},
);
}
}
}
id
}
}
/// Handler for Disconnect message.
impl Handler<Disconnect> for ChatServer {
type Result = ();
fn handle(&mut self, msg: Disconnect, _: &mut Context<Self>) {
// Remove connections from sessions and all 3 scopes
if self.sessions.remove(&msg.id).is_some() {
for sessions in self.user_rooms.values_mut() {
sessions.remove(&msg.id);
}
for sessions in self.post_rooms.values_mut() {
sessions.remove(&msg.id);
}
for sessions in self.community_rooms.values_mut() {
sessions.remove(&msg.id);
}
}
}
}
/// Handler for Message message.
impl Handler<StandardMessage> for ChatServer {
type Result = MessageResult<StandardMessage>;
fn handle(&mut self, msg: StandardMessage, _: &mut Context<Self>) -> Self::Result {
let msg_out = match parse_json_message(self, msg) {
Ok(m) => m,
Err(e) => e.to_string(),
};
println!("Message Sent: {}", msg_out);
MessageResult(msg_out)
}
}
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#[derive(Serialize)]
struct WebsocketResponse<T> {
op: String,
data: T,
}
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fn to_json_string<T>(op: &UserOperation, data: T) -> Result<String, Error>
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where
T: Serialize,
{
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let response = WebsocketResponse {
op: op.to_string(),
data,
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};
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Ok(serde_json::to_string(&response)?)
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}
fn do_user_operation<'a, Data, Response>(
op: UserOperation,
data: &str,
conn: &PooledConnection<ConnectionManager<PgConnection>>,
) -> Result<String, Error>
where
for<'de> Data: Deserialize<'de> + 'a,
Response: Serialize,
Oper<Data>: Perform<Response>,
{
let parsed_data: Data = serde_json::from_str(data)?;
let res = Oper::new(parsed_data).perform(&conn)?;
to_json_string(&op, &res)
}
fn parse_json_message(chat: &mut ChatServer, msg: StandardMessage) -> Result<String, Error> {
let json: Value = serde_json::from_str(&msg.msg)?;
let data = &json["data"].to_string();
let op = &json["op"].as_str().ok_or(APIError {
message: "Unknown op type".to_string(),
})?;
let conn = chat.db.get()?;
let user_operation: UserOperation = UserOperation::from_str(&op)?;
// TODO: none of the chat messages are going to work if stuff is submitted via http api,
// need to move that handling elsewhere
// A DDOS check
chat.check_rate_limit_message(msg.id, false)?;
match user_operation {
UserOperation::Login => do_user_operation::<Login, LoginResponse>(user_operation, data, &conn),
UserOperation::Register => {
chat.check_rate_limit_register(msg.id, true)?;
let register: Register = serde_json::from_str(data)?;
let res = Oper::new(register).perform(&conn)?;
chat.check_rate_limit_register(msg.id, false)?;
to_json_string(&user_operation, &res)
}
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UserOperation::GetUserDetails => {
do_user_operation::<GetUserDetails, GetUserDetailsResponse>(user_operation, data, &conn)
}
UserOperation::SaveUserSettings => {
do_user_operation::<SaveUserSettings, LoginResponse>(user_operation, data, &conn)
}
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UserOperation::AddAdmin => {
let add_admin: AddAdmin = serde_json::from_str(data)?;
let res = Oper::new(add_admin).perform(&conn)?;
let res_str = to_json_string(&user_operation, &res)?;
chat.send_all_message(&res_str, msg.id);
Ok(res_str)
}
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UserOperation::BanUser => {
let ban_user: BanUser = serde_json::from_str(data)?;
let res = Oper::new(ban_user).perform(&conn)?;
let res_str = to_json_string(&user_operation, &res)?;
chat.send_all_message(&res_str, msg.id);
Ok(res_str)
}
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UserOperation::GetReplies => {
do_user_operation::<GetReplies, GetRepliesResponse>(user_operation, data, &conn)
}
UserOperation::GetUserMentions => {
do_user_operation::<GetUserMentions, GetUserMentionsResponse>(user_operation, data, &conn)
}
UserOperation::EditUserMention => {
do_user_operation::<EditUserMention, UserMentionResponse>(user_operation, data, &conn)
}
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UserOperation::MarkAllAsRead => {
do_user_operation::<MarkAllAsRead, GetRepliesResponse>(user_operation, data, &conn)
}
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UserOperation::GetCommunity => {
let get_community: GetCommunity = serde_json::from_str(data)?;
let mut res = Oper::new(get_community).perform(&conn)?;
let community_id = res.community.id;
chat.join_community_room(community_id, msg.id);
res.online = if let Some(community_users) = chat.community_rooms.get(&community_id) {
community_users.len()
} else {
0
};
to_json_string(&user_operation, &res)
}
UserOperation::ListCommunities => {
do_user_operation::<ListCommunities, ListCommunitiesResponse>(user_operation, data, &conn)
}
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UserOperation::CreateCommunity => {
chat.check_rate_limit_register(msg.id, true)?;
let create_community: CreateCommunity = serde_json::from_str(data)?;
let res = Oper::new(create_community).perform(&conn)?;
chat.check_rate_limit_register(msg.id, false)?;
to_json_string(&user_operation, &res)
}
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UserOperation::EditCommunity => {
let edit_community: EditCommunity = serde_json::from_str(data)?;
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let res = Oper::new(edit_community).perform(&conn)?;
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let mut community_sent: CommunityResponse = res.clone();
community_sent.community.user_id = None;
community_sent.community.subscribed = None;
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let community_sent_str = to_json_string(&user_operation, &community_sent)?;
chat.send_community_room_message(community_sent.community.id, &community_sent_str, msg.id);
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to_json_string(&user_operation, &res)
}
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UserOperation::FollowCommunity => {
do_user_operation::<FollowCommunity, CommunityResponse>(user_operation, data, &conn)
}
UserOperation::GetFollowedCommunities => do_user_operation::<
GetFollowedCommunities,
GetFollowedCommunitiesResponse,
>(user_operation, data, &conn),
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UserOperation::BanFromCommunity => {
let ban_from_community: BanFromCommunity = serde_json::from_str(data)?;
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let community_id = ban_from_community.community_id;
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let res = Oper::new(ban_from_community).perform(&conn)?;
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let res_str = to_json_string(&user_operation, &res)?;
chat.send_community_room_message(community_id, &res_str, msg.id);
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Ok(res_str)
}
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UserOperation::AddModToCommunity => {
let mod_add_to_community: AddModToCommunity = serde_json::from_str(data)?;
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let community_id = mod_add_to_community.community_id;
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let res = Oper::new(mod_add_to_community).perform(&conn)?;
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let res_str = to_json_string(&user_operation, &res)?;
chat.send_community_room_message(community_id, &res_str, msg.id);
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Ok(res_str)
}
UserOperation::ListCategories => {
do_user_operation::<ListCategories, ListCategoriesResponse>(user_operation, data, &conn)
}
UserOperation::GetPost => {
let get_post: GetPost = serde_json::from_str(data)?;
let post_id = get_post.id;
chat.join_post_room(post_id, msg.id);
let mut res = Oper::new(get_post).perform(&conn)?;
res.online = if let Some(post_users) = chat.post_rooms.get(&post_id) {
post_users.len()
} else {
0
};
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to_json_string(&user_operation, &res)
}
UserOperation::GetPosts => {
let get_posts: GetPosts = serde_json::from_str(data)?;
if get_posts.community_id.is_none() {
// 0 is the "all" community
chat.join_community_room(0, msg.id);
}
let res = Oper::new(get_posts).perform(&conn)?;
to_json_string(&user_operation, &res)
}
UserOperation::CreatePost => {
chat.check_rate_limit_post(msg.id, true)?;
let create_post: CreatePost = serde_json::from_str(data)?;
let res = Oper::new(create_post).perform(&conn)?;
chat.check_rate_limit_post(msg.id, false)?;
chat.post_sends(UserOperation::CreatePost, res, msg.id)
}
UserOperation::CreatePostLike => {
let create_post_like: CreatePostLike = serde_json::from_str(data)?;
let res = Oper::new(create_post_like).perform(&conn)?;
chat.post_sends(UserOperation::CreatePostLike, res, msg.id)
}
UserOperation::EditPost => {
let edit_post: EditPost = serde_json::from_str(data)?;
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let res = Oper::new(edit_post).perform(&conn)?;
chat.post_sends(UserOperation::EditPost, res, msg.id)
}
UserOperation::SavePost => {
do_user_operation::<SavePost, PostResponse>(user_operation, data, &conn)
}
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UserOperation::CreateComment => {
let create_comment: CreateComment = serde_json::from_str(data)?;
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let res = Oper::new(create_comment).perform(&conn)?;
chat.comment_sends(UserOperation::CreateComment, res, msg.id)
}
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UserOperation::EditComment => {
let edit_comment: EditComment = serde_json::from_str(data)?;
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let res = Oper::new(edit_comment).perform(&conn)?;
chat.comment_sends(UserOperation::EditComment, res, msg.id)
}
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UserOperation::SaveComment => {
do_user_operation::<SaveComment, CommentResponse>(user_operation, data, &conn)
}
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UserOperation::CreateCommentLike => {
let create_comment_like: CreateCommentLike = serde_json::from_str(data)?;
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let res = Oper::new(create_comment_like).perform(&conn)?;
chat.comment_sends(UserOperation::CreateCommentLike, res, msg.id)
}
UserOperation::GetModlog => {
do_user_operation::<GetModlog, GetModlogResponse>(user_operation, data, &conn)
}
UserOperation::CreateSite => {
do_user_operation::<CreateSite, SiteResponse>(user_operation, data, &conn)
}
UserOperation::EditSite => {
let edit_site: EditSite = serde_json::from_str(data)?;
let res = Oper::new(edit_site).perform(&conn)?;
let res_str = to_json_string(&user_operation, &res)?;
chat.send_all_message(&res_str, msg.id);
Ok(res_str)
}
UserOperation::GetSite => {
let get_site: GetSite = serde_json::from_str(data)?;
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let mut res = Oper::new(get_site).perform(&conn)?;
res.online = chat.sessions.len();
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to_json_string(&user_operation, &res)
}
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UserOperation::Search => {
do_user_operation::<Search, SearchResponse>(user_operation, data, &conn)
}
UserOperation::TransferCommunity => {
do_user_operation::<TransferCommunity, GetCommunityResponse>(user_operation, data, &conn)
}
UserOperation::TransferSite => {
do_user_operation::<TransferSite, GetSiteResponse>(user_operation, data, &conn)
}
UserOperation::DeleteAccount => {
do_user_operation::<DeleteAccount, LoginResponse>(user_operation, data, &conn)
}
UserOperation::PasswordReset => {
do_user_operation::<PasswordReset, PasswordResetResponse>(user_operation, data, &conn)
}
UserOperation::PasswordChange => {
do_user_operation::<PasswordChange, LoginResponse>(user_operation, data, &conn)
}
UserOperation::CreatePrivateMessage => {
let create_private_message: CreatePrivateMessage = serde_json::from_str(data)?;
let recipient_id = create_private_message.recipient_id;
let res = Oper::new(create_private_message).perform(&conn)?;
let res_str = to_json_string(&user_operation, &res)?;
chat.send_user_room_message(recipient_id, &res_str, msg.id);
Ok(res_str)
}
UserOperation::EditPrivateMessage => {
do_user_operation::<EditPrivateMessage, PrivateMessageResponse>(user_operation, data, &conn)
}
UserOperation::GetPrivateMessages => {
do_user_operation::<GetPrivateMessages, PrivateMessagesResponse>(user_operation, data, &conn)
}
UserOperation::UserJoin => {
let user_join: UserJoin = serde_json::from_str(data)?;
let res = Oper::new(user_join).perform(&conn)?;
chat.join_user_room(res.user_id, msg.id);
to_json_string(&user_operation, &res)
}
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}
}