// Copyright (C) 2018-2021 Vincent Ambo <tazjin@tvl.su>
//
// This file is part of Converse.
//
// This program is free software: you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see
// <https://www.gnu.org/licenses/>.
//! This module implements the database executor, which holds the
//! database connection and performs queries on it.
use actix::prelude::*;
use diesel::{self, sql_query};
use diesel::sql_types::Text;
use diesel::prelude::*;
use diesel::r2d2::{Pool, ConnectionManager};
use crate::models::*;
use crate::errors::{ConverseError, Result};
/// Raw PostgreSQL query used to perform full-text search on posts
/// with a supplied phrase. For now, the query language is hardcoded
/// to English and only "plain" queries (i.e. no searches for exact
/// matches or more advanced query syntax) are supported.
const SEARCH_QUERY: &'static str = r#"
WITH search_query (query) AS (VALUES (plainto_tsquery('english', $1)))
SELECT post_id,
thread_id,
author,
title,
ts_headline('english', body, query) AS headline
FROM search_index, search_query
WHERE document @@ query
ORDER BY ts_rank(document, query) DESC
LIMIT 50
"#;
const REFRESH_QUERY: &'static str = "REFRESH MATERIALIZED VIEW search_index";
pub struct DbExecutor(pub Pool<ConnectionManager<PgConnection>>);
impl DbExecutor {
/// Request a list of threads.
//
// TODO(tazjin): This should support pagination.
pub fn list_threads(&self) -> Result<Vec<ThreadIndex>> {
use crate::schema::thread_index::dsl::*;
let conn = self.0.get()?;
let results = thread_index
.load::<ThreadIndex>(&conn)?;
Ok(results)
}
/// Look up a user based on their email-address. If the user does
/// not exist, it is created.
pub fn lookup_or_create_user(&self, user_email: &str, user_name: &str) -> Result<User> {
use crate::schema::users;
use crate::schema::users::dsl::*;
let conn = self.0.get()?;
let opt_user = users
.filter(email.eq(email))
.first(&conn).optional()?;
if let Some(user) = opt_user {
Ok(user)
} else {
let new_user = NewUser {
email: user_email.to_string(),
name: user_name.to_string(),
};
let user: User = diesel::insert_into(users::table)
.values(&new_user)
.get_result(&conn)?;
info!("Created new user {} with ID {}", new_user.email, user.id);
Ok(user)
}
}
/// Fetch a specific thread and return it with its posts.
pub fn get_thread(&self, thread_id: i32) -> Result<(Thread, Vec<SimplePost>)> {
use crate::schema::threads::dsl::*;
use crate::schema::simple_posts::dsl::id;
let conn = self.0.get()?;
let thread_result: Thread = threads
.find(thread_id).first(&conn)?;
let post_list = SimplePost::belonging_to(&thread_result)
.order_by(id.asc())
.load::<SimplePost>(&conn)?;
Ok((thread_result, post_list))
}
/// Fetch a specific post.
pub fn get_post(&self, post_id: i32) -> Result<SimplePost> {
use crate::schema::simple_posts::dsl::*;
let conn = self.0.get()?;
Ok(simple_posts.find(post_id).first(&conn)?)
}
/// Update the content of a post.
pub fn update_post(&self, post_id: i32, post_text: String) -> Result<Post> {
use crate::schema::posts::dsl::*;
let conn = self.0.get()?;
let updated = diesel::update(posts.find(post_id))
.set(body.eq(post_text))
.get_result(&conn)?;
Ok(updated)
}
/// Create a new thread.
pub fn create_thread(&self, new_thread: NewThread, post_text: String) -> Result<Thread> {
use crate::schema::threads;
use crate::schema::posts;
let conn = self.0.get()?;
conn.transaction::<Thread, ConverseError, _>(|| {
// First insert the thread structure itself
let thread: Thread = diesel::insert_into(threads::table)
.values(&new_thread)
.get_result(&conn)?;
// ... then create the first post in the thread.
let new_post = NewPost {
thread_id: thread.id,
body: post_text,
user_id: new_thread.user_id,
};
diesel::insert_into(posts::table)
.values(&new_post)
.execute(&conn)?;
Ok(thread)
})
}
/// Create a new post.
pub fn create_post(&self, new_post: NewPost) -> Result<Post> {
use crate::schema::posts;
let conn = self.0.get()?;
let closed: bool = {
use crate::schema::threads::dsl::*;
threads.select(closed)
.find(new_post.thread_id)
.first(&conn)?
};
if closed {
return Err(ConverseError::ThreadClosed {
id: new_post.thread_id
})
}
Ok(diesel::insert_into(posts::table)
.values(&new_post)
.get_result(&conn)?)
}
/// Search for posts.
pub fn search_posts(&self, query: String) -> Result<Vec<SearchResult>> {
let conn = self.0.get()?;
let search_results = sql_query(SEARCH_QUERY)
.bind::<Text, _>(query)
.get_results::<SearchResult>(&conn)?;
Ok(search_results)
}
/// Trigger a refresh of the view used for full-text searching.
pub fn refresh_search_view(&self) -> Result<()> {
let conn = self.0.get()?;
debug!("Refreshing search_index view in DB");
sql_query(REFRESH_QUERY).execute(&conn)?;
Ok(())
}
}
// Old actor implementation:
impl Actor for DbExecutor {
type Context = SyncContext<Self>;
}
/// Message used to look up a user based on their email-address. If
/// the user does not exist, it is created.
pub struct LookupOrCreateUser {
pub email: String,
pub name: String,
}
message!(LookupOrCreateUser, Result<User>);
impl Handler<LookupOrCreateUser> for DbExecutor {
type Result = <LookupOrCreateUser as Message>::Result;
fn handle(&mut self,
_: LookupOrCreateUser,
_: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message used to fetch a specific thread. Returns the thread and
/// its posts.
pub struct GetThread(pub i32);
message!(GetThread, Result<(Thread, Vec<SimplePost>)>);
impl Handler<GetThread> for DbExecutor {
type Result = <GetThread as Message>::Result;
fn handle(&mut self, _: GetThread, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message used to fetch a specific post.
#[derive(Deserialize, Debug)]
pub struct GetPost { pub id: i32 }
message!(GetPost, Result<SimplePost>);
impl Handler<GetPost> for DbExecutor {
type Result = <GetPost as Message>::Result;
fn handle(&mut self, _: GetPost, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message used to update the content of a post.
#[derive(Deserialize)]
pub struct UpdatePost {
pub post_id: i32,
pub post: String,
}
message!(UpdatePost, Result<Post>);
impl Handler<UpdatePost> for DbExecutor {
type Result = Result<Post>;
fn handle(&mut self, _: UpdatePost, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message used to create a new thread
pub struct CreateThread {
pub new_thread: NewThread,
pub post: String,
}
message!(CreateThread, Result<Thread>);
impl Handler<CreateThread> for DbExecutor {
type Result = <CreateThread as Message>::Result;
fn handle(&mut self, _: CreateThread, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message used to create a new reply
pub struct CreatePost(pub NewPost);
message!(CreatePost, Result<Post>);
impl Handler<CreatePost> for DbExecutor {
type Result = <CreatePost as Message>::Result;
fn handle(&mut self, _: CreatePost, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message used to search for posts
#[derive(Deserialize)]
pub struct SearchPosts { pub query: String }
message!(SearchPosts, Result<Vec<SearchResult>>);
impl Handler<SearchPosts> for DbExecutor {
type Result = <SearchPosts as Message>::Result;
fn handle(&mut self, _: SearchPosts, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
/// Message that triggers a refresh of the view used for full-text
/// searching.
pub struct RefreshSearchView;
message!(RefreshSearchView, Result<()>);
impl Handler<RefreshSearchView> for DbExecutor {
type Result = Result<()>;
fn handle(&mut self, _: RefreshSearchView, _: &mut Self::Context) -> Self::Result {
unimplemented!()
}
}
