blog/backend/src/cache.rs
2023-02-12 11:09:57 +01:00

332 lines
11 KiB
Rust

use anyhow::Result;
use chrono::prelude::*;
use diesel::prelude::*;
use lazy_static::lazy_static;
use r2d2_redis::{r2d2, redis, RedisConnectionManager};
use serde::{Deserialize, Serialize};
use crate::{config, db, markdown, web};
pub type RedisPool = r2d2::Pool<RedisConnectionManager>;
pub type ConnectionPool = r2d2::PooledConnection<RedisConnectionManager>;
pub type Connection = redis::Connection;
pub fn establish_connection() -> Result<redis::Connection> {
Ok(redis::Client::open(config::CONFIG.redis_url.as_str())?.get_connection()?)
}
pub fn pool() -> Result<RedisPool> {
Ok(r2d2::Pool::builder().build(RedisConnectionManager::new(
config::CONFIG.redis_url.as_str(),
)?)?)
}
lazy_static! {
pub static ref POOL: RedisPool = pool().unwrap();
}
pub mod keys {
pub const POSTS: &str = "posts";
pub const POST: &str = "post:";
pub fn post(id: i32) -> String {
format!("{}{}", POST, id)
}
pub const TAGS: &str = "tags";
pub const TAG_POSTS: &str = "tag_posts:";
pub fn tag_posts(id: i32) -> String {
format!("{}{}", TAG_POSTS, id)
}
}
pub fn clear(redis_conn: &mut Connection) -> Result<()> {
redis::cmd("UNLINK").arg(keys::POSTS).query(redis_conn)?;
for key in redis::cmd("KEYS")
.arg(format!("{}*", keys::POST))
.query::<Vec<String>>(redis_conn)?
{
redis::cmd("UNLINK").arg(key).query(redis_conn)?;
}
redis::cmd("UNLINK").arg(keys::TAGS).query(redis_conn)?;
for key in redis::cmd("KEYS")
.arg(format!("{}*", keys::TAG_POSTS))
.query::<Vec<String>>(redis_conn)?
{
redis::cmd("UNLINK").arg(key).query(redis_conn)?;
}
Ok(())
}
pub fn cache_posts(
db_conn: &mut db::Connection,
redis_conn: &mut Connection,
) -> Result<Vec<web::templates::PostIndexPost>> {
if let Some(s) = redis::cmd("GET")
.arg(keys::POSTS)
.query::<Option<String>>(redis_conn)?
{
Ok(serde_json::from_str(&s)?)
} else {
let posts_cache: Vec<web::templates::PostIndexPost> = db::schema::posts::table
.select((
db::schema::posts::id,
db::schema::posts::name,
db::schema::posts::slug,
db::schema::posts::description,
db::schema::posts::published_at,
db::schema::posts::edited_at,
))
.filter(db::schema::posts::active)
.order(db::schema::posts::published_at.desc())
.load::<(i32, String, String, String, NaiveDate, Option<NaiveDate>)>(db_conn)?
.into_iter()
.map(
|p: (i32, String, String, String, NaiveDate, Option<NaiveDate>)| -> Result<_> {
let (id, name, slug, description, published_at, edited_at) = p;
let tags = web::get_tags_by_post(id, db_conn)?;
Ok(web::templates::PostIndexPost {
name,
slug,
description,
published_at,
edited_at,
tags,
})
},
)
.collect::<Result<_>>()?;
redis::cmd("SET")
.arg(keys::POSTS)
.arg(serde_json::to_string(&posts_cache)?)
.query(redis_conn)?;
redis::cmd("EXPIRE")
.arg(keys::POSTS)
.arg(config::CONFIG.cache_ttl)
.query(redis_conn)?;
Ok(posts_cache)
}
}
#[derive(Serialize, Deserialize, Debug)]
pub struct PostWithoutDescription {
pub name: String,
pub slug: String,
pub published_at: NaiveDate,
pub edited_at: Option<NaiveDate>,
pub tags: Vec<String>,
pub content: String,
}
#[derive(Serialize, Deserialize, Debug)]
pub struct PostWithoutContent {
pub name: String,
pub slug: String,
pub description: String,
pub published_at: NaiveDate,
pub edited_at: Option<NaiveDate>,
pub tags: Vec<String>,
}
pub fn cache_post(
id: i32,
db_conn: &mut db::Connection,
redis_conn: &mut Connection,
) -> Result<PostWithoutDescription> {
let key = keys::post(id);
if let Some(s) = redis::cmd("GET")
.arg(&key)
.query::<Option<String>>(redis_conn)?
{
Ok(serde_json::from_str(&s)?)
} else {
let post = db::schema::posts::table
.filter(db::schema::posts::id.eq(id))
.first::<db::models::Post>(db_conn)?;
let post_cache = PostWithoutDescription {
name: post.name,
slug: post.slug,
published_at: post.published_at,
edited_at: post.edited_at,
tags: web::get_tags_by_post(id, db_conn)?,
content: markdown::to_html(&post.content),
};
redis::cmd("SET")
.arg(&key)
.arg(serde_json::to_string(&post_cache)?)
.query(redis_conn)?;
redis::cmd("EXPIRE")
.arg(key)
.arg(config::CONFIG.cache_ttl)
.query(redis_conn)?;
Ok(post_cache)
}
}
#[derive(Serialize, Deserialize, Debug)]
pub struct PostsByTag {
pub name: String,
pub posts: Vec<PostWithoutContent>,
}
pub fn cache_tags(
db_conn: &mut db::Connection,
redis_conn: &mut Connection,
) -> Result<Vec<PostsByTag>> {
if let Some(s) = redis::cmd("GET")
.arg(keys::TAGS)
.query::<Option<String>>(redis_conn)?
{
Ok(serde_json::from_str(&s)?)
} else {
let tags = db::schema::tags::table
.select((db::schema::tags::id, db::schema::tags::name))
.order(db::schema::tags::name)
.load::<(i32, String)>(db_conn)?;
let posts_by_tag = tags
.into_iter()
.map(|(id, name)| -> Result<_> {
let post_tag_post_ids = db::schema::post_tags::table
.select(db::schema::post_tags::post_id)
.filter(db::schema::post_tags::tag_id.eq(id))
.load::<i32>(db_conn)?;
let posts = db::schema::posts::table
.select((
db::schema::posts::id,
db::schema::posts::name,
db::schema::posts::slug,
db::schema::posts::description,
db::schema::posts::published_at,
db::schema::posts::edited_at,
))
.filter(db::schema::posts::active)
.filter(db::schema::posts::id.eq_any(post_tag_post_ids))
.order(db::schema::posts::published_at.desc())
.load::<(i32, String, String, String, NaiveDate, Option<NaiveDate>)>(db_conn)?;
Ok(
PostsByTag {
name,
posts:
posts
.into_iter()
.map(
|p: (
i32,
String,
String,
String,
NaiveDate,
Option<NaiveDate>,
)|
-> Result<_> {
let (id, name, slug, description, published_at, edited_at) =
p;
let tags = web::get_tags_by_post(id, db_conn)?;
Ok(PostWithoutContent {
name,
slug,
description,
published_at,
edited_at,
tags,
})
},
)
.collect::<Result<Vec<_>>>()?,
},
)
})
.collect::<Result<Vec<_>>>()?;
redis::cmd("SET")
.arg(keys::TAGS)
.arg(serde_json::to_string(&posts_by_tag)?)
.query(redis_conn)?;
redis::cmd("EXPIRE")
.arg(keys::TAGS)
.arg(config::CONFIG.cache_ttl)
.query(redis_conn)?;
Ok(posts_by_tag)
}
}
pub fn cache_tag_posts(
id: i32,
db_conn: &mut db::Connection,
redis_conn: &mut Connection,
) -> Result<Vec<web::templates::PostIndexPost>> {
let key = keys::tag_posts(id);
if let Some(s) = redis::cmd("GET")
.arg(&key)
.query::<Option<String>>(redis_conn)?
{
Ok(serde_json::from_str(&s)?)
} else {
let post_tag_post_ids = db::schema::post_tags::table
.select(db::schema::post_tags::post_id)
.filter(db::schema::post_tags::tag_id.eq(id))
.load::<i32>(db_conn)?;
let posts: Vec<web::templates::PostIndexPost> = db::schema::posts::table
.select((
db::schema::posts::id,
db::schema::posts::name,
db::schema::posts::slug,
db::schema::posts::description,
db::schema::posts::published_at,
db::schema::posts::edited_at,
))
.filter(db::schema::posts::id.eq_any(post_tag_post_ids))
.filter(db::schema::posts::active)
.order(db::schema::posts::published_at.desc())
.load::<(i32, String, String, String, NaiveDate, Option<NaiveDate>)>(db_conn)?
.into_iter()
.map(
|p: (i32, String, String, String, NaiveDate, Option<NaiveDate>)| -> Result<_> {
let (id, name, slug, description, published_at, edited_at) = p;
let tags = web::get_tags_by_post(id, db_conn)?;
Ok(web::templates::PostIndexPost {
name,
slug,
description,
published_at,
edited_at,
tags,
})
},
)
.collect::<Result<_>>()?;
redis::cmd("SET")
.arg(&key)
.arg(serde_json::to_string(&posts)?)
.query(redis_conn)?;
redis::cmd("EXPIRE")
.arg(key)
.arg(config::CONFIG.cache_ttl)
.query(redis_conn)?;
Ok(posts)
}
}