Merge pull request 'Added caching system' (#1) from caching into master

Reviewed-on: #1

.gitignore

@@ -1,3 +1,4 @@
 debug.log
 .vscode/
 .idea/
+dump.rdb

backend/README.md

@@ -1,3 +1,10 @@
 # Backend
 
-TODO
+## What is this?
+
+This is just an orginizational way of keeping the backend services together (so I don't lose my mind).
+
+## Projects
+
+- [`public`](./public/README.md) - a RESTful API service
+- [`task`](./task/README.md) - a task scheduler service

backend/public/Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "addr2line"
@@ -59,6 +59,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "arc-swap"
+version = "1.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69f7f8c3906b62b754cd5326047894316021dcfe5a194c8ea52bdd94934a3457"
+
 [[package]]
 name = "async-trait"
 version = "0.1.82"
@@ -209,6 +215,16 @@ version = "1.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "428d9aa8fbc0670b7b8d6030a7fadd0f86151cae55e4dbbece15f3780a3dfaf3"
 
+[[package]]
+name = "bytes-utils"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7dafe3a8757b027e2be6e4e5601ed563c55989fcf1546e933c66c8eb3a058d35"
+dependencies = [
+ "bytes",
+ "either",
+]
+
 [[package]]
 name = "cc"
 version = "1.1.21"
@@ -253,6 +269,12 @@ version = "0.9.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2459377285ad874054d797f3ccebf984978aa39129f6eafde5cdc8315b612f8"
 
+[[package]]
+name = "cookie-factory"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "396de984970346b0d9e93d1415082923c679e5ae5c3ee3dcbd104f5610af126b"
+
 [[package]]
 name = "core-foundation-sys"
 version = "0.8.7"
@@ -283,6 +305,12 @@ version = "2.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "19d374276b40fb8bbdee95aef7c7fa6b5316ec764510eb64b8dd0e2ed0d7e7f5"
 
+[[package]]
+name = "crc16"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "338089f42c427b86394a5ee60ff321da23a5c89c9d89514c829687b26359fcff"
+
 [[package]]
 name = "crossbeam-queue"
 version = "0.3.11"
@@ -403,6 +431,15 @@ version = "2.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e8c02a5121d4ea3eb16a80748c74f5549a5665e4c21333c6098f283870fbdea6"
 
+[[package]]
+name = "float-cmp"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b09cf3155332e944990140d967ff5eceb70df778b34f77d8075db46e4704e6d8"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "flume"
 version = "0.11.0"
@@ -439,6 +476,43 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "fred"
+version = "10.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3a7b2fd0f08b23315c13b6156f971aeedb6f75fb16a29ac1872d2eabccc1490e"
+dependencies = [
+ "arc-swap",
+ "async-trait",
+ "bytes",
+ "bytes-utils",
+ "float-cmp",
+ "fred-macros",
+ "futures",
+ "log",
+ "parking_lot",
+ "rand",
+ "redis-protocol",
+ "semver",
+ "socket2",
+ "tokio",
+ "tokio-stream",
+ "tokio-util",
+ "url",
+ "urlencoding",
+]
+
+[[package]]
+name = "fred-macros"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1458c6e22d36d61507034d5afecc64f105c1d39712b7ac6ec3b352c423f715cc"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "futures"
 version = "0.3.30"
@@ -1180,6 +1254,7 @@ dependencies = [
  "axum",
  "chrono",
  "dotenvy",
+ "fred",
  "serde",
  "serde_json",
  "sqlx",
@@ -1254,6 +1329,20 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "redis-protocol"
+version = "6.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9cdba59219406899220fc4cdfd17a95191ba9c9afb719b5fa5a083d63109a9f1"
+dependencies = [
+ "bytes",
+ "bytes-utils",
+ "cookie-factory",
+ "crc16",
+ "log",
+ "nom",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.5.4"
@@ -1420,6 +1509,12 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "semver"
+version = "1.0.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56e6fa9c48d24d85fb3de5ad847117517440f6beceb7798af16b4a87d616b8d0"
+
 [[package]]
 name = "serde"
 version = "1.0.210"
@@ -2142,6 +2237,12 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "urlencoding"
+version = "2.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "daf8dba3b7eb870caf1ddeed7bc9d2a049f3cfdfae7cb521b087cc33ae4c49da"
+
 [[package]]
 name = "valuable"
 version = "0.1.0"

backend/public/Cargo.toml

@@ -24,3 +24,4 @@ serde = "1.0.210"
 serde_json = "1.0.128"
 chrono = "0.4.38"
 xml = "0.8.20"
+fred = "10.1.0"

backend/public/README.md

@@ -0,0 +1,20 @@
+# Backend API
+
+also known as `public`
+
+## What is this?
+
+This is a RESTful API service. Most of the data retrival, requesting, and processing happens here.
+
+## Things you should know
+
+### Environment variables
+
+`public` uses a `.env` file at the root of the project. The file takes standard environment variables (like enviroment variables you would put into a `.bashrc` or ad-hoc into your shell).
+
+For `public` to work properly, please make sure to first create the `.env` file, then fill out the following environment variables:
+
+- `RUST_ENV` - needed for letting the service that we are working in either `development` or `production`
+- `DATABASE_URL` - needed for connecting to Postgres
+- `REDIS_URL` - needed for connecting to the cache (Redis or Valkey)
+- `BASE_URI_WEB` - needed for connecting to the frontend user interface of the system to this service

backend/public/src/main.rs

@@ -1,11 +1,13 @@
-use axum::{http::Method, Router};
+use axum::Router;
 use config::config;
-use sqlx::{postgres::PgPoolOptions, PgPool};
+use fred::prelude::*;
+use sqlx::postgres::PgPoolOptions;
 use std::fs::File;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::net::TcpListener;
 use tokio::signal;
+use tokio::sync::Mutex;
 use tower_governor::{governor::GovernorConfigBuilder, GovernorLayer};
 use tower_http::{
     cors::{Any, CorsLayer},
@@ -16,12 +18,9 @@ use tracing_subscriber::{filter, layer::SubscriberExt, prelude::*, util::Subscri
 mod config;
 mod datasources;
 mod routes;
+mod state;
 mod utils;
 
-pub struct AppState {
-    db: PgPool,
-}
-
 #[tokio::main]
 async fn main() {
     // setting up configuration
@@ -87,6 +86,11 @@ async fn main() {
     // grabbing the database url from our env variables
     let db_connection_str = std::env::var("DATABASE_URL")
         .unwrap_or_else(|_| "postgres://postgres:password@localhost".to_string());
+    let redis_url = match std::env::var("REDIS_URL").unwrap().as_str() {
+        // TODO: fix the unwrap ^
+        "" => "redis://localhost:6379".to_string(),
+        x => x.to_string(),
+    };
 
     // set up connection pool
     let pool = PgPoolOptions::new()
@@ -96,7 +100,24 @@ async fn main() {
         .await
         .expect("Failed to connect to database");
 
-    let app_state = AppState { db: pool.clone() };
+    let pool_size = 8;
+    let config = Config::from_url(&redis_url).unwrap(); // TODO: fix the unwrap <<<
+
+    let redis_pool = Builder::from_config(config)
+        .with_performance_config(|config| {
+            config.default_command_timeout = Duration::from_secs(60);
+        })
+        .set_policy(ReconnectPolicy::new_exponential(0, 100, 30_000, 2))
+        .build_pool(pool_size)
+        .expect("Failed to create cache pool");
+
+    if std::env::var("REDIS_URL").unwrap() != "" {
+        // TODO: fix the unwrap ^
+        redis_pool.init().await.expect("Failed to connect to cache");
+        let _ = redis_pool.flushall::<i32>(false).await;
+    }
+
+    let app_state = Arc::new(Mutex::new(state::AppInternalState::new(pool, redis_pool)));
 
     // build our application with some routes
     let app = Router::new()

backend/public/src/routes/authors.rs

@@ -5,14 +5,14 @@ use axum::{
     routing::get,
     Json,
 };
+use fred::types::Expiration;
 use serde::{Deserialize, Serialize};
-use sqlx::{Pool, Postgres};
 
-use crate::{datasources::authors::AuthorsDatasource, AppState};
+use crate::{datasources::authors::AuthorsDatasource, state::AppState};
 
 use super::comments::Pagination;
 
-#[derive(Serialize)]
+#[derive(Deserialize, Serialize, Clone)]
 pub struct Author {
     pub author_id: i32,
     pub first_name: String,
@@ -21,7 +21,7 @@ pub struct Author {
     pub image: Option<String>,
 }
 
-#[derive(Deserialize)]
+#[derive(Deserialize, Serialize, Clone)]
 pub struct AuthorGetOneParams {
     pub id: i32,
 }
@@ -33,34 +33,104 @@ impl AuthorsRoute {
             .route("/", get(AuthorsRoute::get_all))
             .route("/:id", get(AuthorsRoute::get_one))
             .route("/:id/posts", get(AuthorsRoute::get_authors_posts))
-            .with_state(app_state.db.clone())
+            .with_state(app_state.clone())
     }
 
     async fn get_all(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Json(pagination): Json<Pagination>,
     ) -> impl IntoResponse {
-        match AuthorsDatasource::get_all(&pool, pagination).await {
+        let mut state = app_state.lock().await;
-            Ok(a) => Ok(Json(a)),
+        let cached: Option<Vec<Author>> = state
+            .cache
+            .get(String::from("authors:all"))
+            .await
+            .unwrap_or(None);
+
+        if let Some(authors) = cached {
+            tracing::info!("grabbing all authors from cache");
+            return Ok(Json(authors));
+        }
+
+        match AuthorsDatasource::get_all(&state.database, pagination).await {
+            Ok(authors) => {
+                tracing::info!("grabbing all authors from the database");
+                if let a = &authors {
+                    let author_cloned = a.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                String::from("authors:all"),
+                                &author_cloned,
+                                Some(Expiration::EX(5)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                }
+                Ok(Json(authors))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     async fn get_one(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Path(params): Path<AuthorGetOneParams>,
     ) -> impl IntoResponse {
-        match AuthorsDatasource::get_one(&pool, params.id).await {
+        let mut state = app_state.lock().await;
-            Ok(a) => Ok(Json(a)),
+        let cached: Option<Author> = state
+            .cache
+            .get(format!("authors:{}", params.id))
+            .await
+            .unwrap_or(None);
+
+        if let Some(author) = cached {
+            tracing::info!("grabbing one author from cache");
+            return Ok(Json(author));
+        }
+
+        match AuthorsDatasource::get_one(&state.database, params.id).await {
+            Ok(author) => {
+                tracing::info!("grabbing all authors from the database");
+                if let a = &author {
+                    let author_cloned = a.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                format!("authors:{}", author_cloned.author_id),
+                                &author_cloned,
+                                Some(Expiration::EX(5)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                }
+                Ok(Json(author))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     async fn get_authors_posts(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Path(params): Path<AuthorGetOneParams>,
     ) -> impl IntoResponse {
-        match AuthorsDatasource::get_authors_posts(&pool, params.id).await {
+        let state = app_state.lock().await;
+
+        match AuthorsDatasource::get_authors_posts(&state.database, params.id).await {
             Ok(p) => Ok(Json(p)),
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }

backend/public/src/routes/comments.rs

@@ -1,5 +1,5 @@
-use super::posts::serialize_datetime;
+use super::posts::{deserialize_datetime, serialize_datetime};
-use crate::{datasources::comments::CommentsDatasource, AppState};
+use crate::{datasources::comments::CommentsDatasource, state::AppState};
 use axum::{
     extract::{Path, State},
     http::StatusCode,
@@ -8,33 +8,34 @@ use axum::{
     Json,
 };
 use chrono::Utc;
+use fred::types::{Expiration, SetOptions};
 use serde::{Deserialize, Serialize};
-use sqlx::{Pool, Postgres};
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Serialize, Debug)]
 pub struct CommentInputPayload {
     pub name: String,
     pub body: String,
     pub post_id: i32,
 }
 
-#[derive(Deserialize)]
+#[derive(Deserialize, Serialize)]
 pub struct CommentPathParams {
     id: i32,
 }
 
-#[derive(Deserialize)]
+#[derive(Deserialize, Serialize)]
 pub struct Pagination {
     pub page_number: i64,
     pub page_size: i64,
 }
 
-#[derive(sqlx::FromRow, Serialize, Debug)]
+#[derive(sqlx::FromRow, Deserialize, Serialize, Debug, Clone)]
 pub struct Comment {
     pub comment_id: i32,
     pub name: String,
     pub body: String,
     #[serde(serialize_with = "serialize_datetime")]
+    #[serde(deserialize_with = "deserialize_datetime")]
     pub created_at: Option<chrono::DateTime<Utc>>,
 }
 
@@ -46,34 +47,61 @@ impl CommentsRoute {
             .route("/post/:id", get(CommentsRoute::get_post_comments))
             .route("/add", post(CommentsRoute::insert_comment))
             .route("/index", get(CommentsRoute::get_comments_index))
-            .with_state(app_state.db.clone())
+            .with_state(app_state.clone())
     }
 
     async fn get_post_comments(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Path(params): Path<CommentPathParams>,
     ) -> impl IntoResponse {
-        match CommentsDatasource::get_posts_comments(&pool, params.id).await {
+        let state = app_state.lock().await;
+
+        match CommentsDatasource::get_posts_comments(&state.database, params.id).await {
             Ok(c) => Ok(Json(c)),
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
-    //
+
     async fn insert_comment(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Json(input): Json<CommentInputPayload>,
     ) -> impl IntoResponse {
-        match CommentsDatasource::insert_comment(&pool, input).await {
+        let state = app_state.lock().await;
-            Ok(c) => Ok((StatusCode::CREATED, Json(c))),
+
+        match CommentsDatasource::insert_comment(&state.database, input).await {
+            Ok(c) => {
+                if let co = &c {
+                    let co = c.clone();
+                    let state = app_state.clone();
+
+                    tokio::spawn(async move {
+                        tracing::info!("update cache if key already exists!");
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                format!("comments:{}", co.comment_id),
+                                &co,
+                                Some(Expiration::EX(60 * 15)),
+                                Some(SetOptions::XX),
+                                false,
+                            )
+                            .await;
+                    });
+                }
+                Ok((StatusCode::CREATED, Json(c)))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     async fn get_comments_index(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Json(pagination): Json<Pagination>,
     ) -> impl IntoResponse {
-        match CommentsDatasource::get_index_comments(&pool, pagination).await {
+        let state = app_state.lock().await;
+
+        match CommentsDatasource::get_index_comments(&state.database, pagination).await {
             Ok(c) => Ok(Json(c)),
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }

backend/public/src/routes/posts.rs

@@ -1,7 +1,8 @@
 use std::collections::HashMap;
+use std::fmt;
 
 use crate::utils::rss;
-use crate::{datasources::posts::PostsDatasource, AppState};
+use crate::{datasources::posts::PostsDatasource, state::AppState};
 use axum::http::{HeaderMap, HeaderValue};
 use axum::{
     extract::{Path, State},
@@ -11,10 +12,10 @@ use axum::{
     Json, Router,
 };
 use chrono::Utc;
-use serde::{Deserialize, Serialize, Serializer};
+use fred::types::Expiration;
-use sqlx::{Pool, Postgres};
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
 
-#[derive(sqlx::FromRow, Serialize, Debug, Clone)]
+#[derive(sqlx::FromRow, Deserialize, Serialize, Debug, Clone)]
 pub struct Post {
     pub post_id: i32,
     pub author_id: Option<i32>,
@@ -23,10 +24,11 @@ pub struct Post {
     pub title: String,
     pub body: String,
     #[serde(serialize_with = "serialize_datetime")]
+    #[serde(deserialize_with = "deserialize_datetime")]
     pub created_at: Option<chrono::DateTime<Utc>>,
 }
 
-#[derive(sqlx::FromRow, Serialize, Debug)]
+#[derive(sqlx::FromRow, Deserialize, Serialize, Debug, Clone)]
 pub struct PostFeaturedVariant {
     pub post_id: i32,
     pub author_id: Option<i32>,
@@ -35,6 +37,7 @@ pub struct PostFeaturedVariant {
     pub title: String,
     pub body: String,
     #[serde(serialize_with = "serialize_datetime")]
+    #[serde(deserialize_with = "deserialize_datetime")]
     pub created_at: Option<chrono::DateTime<Utc>>,
     pub is_featured: Option<bool>,
 }
@@ -56,63 +59,275 @@ impl PostsRoute {
             .route("/hot", get(PostsRoute::get_hot_posts))
             .route("/featured", get(PostsRoute::get_featured_posts))
             .route("/rss", get(PostsRoute::get_rss_posts))
-            .with_state(app_state.db.clone())
+            .with_state(app_state.clone())
     }
 
     // get all posts
-    async fn get_all(State(pool): State<Pool<Postgres>>) -> impl IntoResponse {
+    async fn get_all(State(app_state): State<AppState>) -> impl IntoResponse {
-        match PostsDatasource::get_all(&pool).await {
+        let mut state = app_state.lock().await;
-            Ok(posts) => Ok(Json(posts)),
+        let cached: Option<Vec<Post>> = state
+            .cache
+            .get(String::from("posts:all"))
+            .await
+            .unwrap_or(None);
+
+        if let Some(posts) = cached {
+            tracing::info!("grabbing all posts from cache");
+            return Ok(Json(posts));
+        };
+
+        match PostsDatasource::get_all(&state.database).await {
+            Ok(posts) => {
+                tracing::info!("grabbing all posts from database");
+                if let p = &posts {
+                    let posts = p.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                String::from("posts:all"),
+                                &posts,
+                                Some(Expiration::EX(10)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                };
+
+                Ok(Json(posts))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     // get one post
     async fn get_one(
-        State(pool): State<Pool<Postgres>>,
+        State(app_state): State<AppState>,
         Path(params): Path<PostGetOneParams>,
     ) -> impl IntoResponse {
-        match PostsDatasource::get_one(&pool, params.id).await {
+        let mut state = app_state.lock().await;
-            Ok(post) => Ok(Json(post)),
+        let cached: Option<PostFeaturedVariant> = state
+            .cache
+            .get(format!("posts:{}", params.id))
+            .await
+            .unwrap_or(None);
+
+        if let Some(post) = cached {
+            tracing::info!("grabbing one post from cache");
+            return Ok(Json(post));
+        };
+
+        match PostsDatasource::get_one(&state.database, params.id).await {
+            Ok(post) => {
+                tracing::info!("grabbing one post from database");
+                if let p = &post {
+                    let post = p.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                format!("posts:{}", params.id),
+                                &post,
+                                Some(Expiration::EX(10)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                };
+
+                Ok(Json(post))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     // get recent posts
-    async fn get_recent_posts(State(pool): State<Pool<Postgres>>) -> impl IntoResponse {
+    async fn get_recent_posts(State(app_state): State<AppState>) -> impl IntoResponse {
-        match PostsDatasource::get_recent(&pool).await {
+        let mut state = app_state.lock().await;
-            Ok(posts) => Ok(Json(posts)),
+        let cached: Option<Vec<Post>> = state
+            .cache
+            .get(String::from("posts:recent"))
+            .await
+            .unwrap_or(None);
+
+        if let Some(posts) = cached {
+            tracing::info!("grabbing recent posts from cache");
+            return Ok(Json(posts));
+        };
+
+        match PostsDatasource::get_recent(&state.database).await {
+            Ok(posts) => {
+                tracing::info!("grabbing recent posts from database");
+                if let p = &posts {
+                    let posts = p.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                String::from("posts:recent"),
+                                &posts,
+                                Some(Expiration::EX(5)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                };
+
+                Ok(Json(posts))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     // get the top three posts with the highest view count
-    async fn get_popular_posts(State(pool): State<Pool<Postgres>>) -> impl IntoResponse {
+    async fn get_popular_posts(State(app_state): State<AppState>) -> impl IntoResponse {
-        match PostsDatasource::get_popular(&pool).await {
+        let mut state = app_state.lock().await;
-            Ok(posts) => Ok(Json(posts)),
+        let cached: Option<Vec<Post>> = state
+            .cache
+            .get(String::from("posts:popular"))
+            .await
+            .unwrap_or(None);
+
+        if let Some(posts) = cached {
+            tracing::info!("grabbing popular posts from cache");
+            return Ok(Json(posts));
+        };
+
+        match PostsDatasource::get_popular(&state.database).await {
+            Ok(posts) => {
+                tracing::info!("grabbing popular posts from database");
+                if let p = &posts {
+                    let posts = p.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                String::from("posts:popular"),
+                                &posts,
+                                Some(Expiration::EX(5)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                };
+
+                Ok(Json(posts))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     // get the top three posts with the most comments
-    async fn get_hot_posts(State(pool): State<Pool<Postgres>>) -> impl IntoResponse {
+    async fn get_hot_posts(State(app_state): State<AppState>) -> impl IntoResponse {
-        match PostsDatasource::get_hot(&pool).await {
+        let mut state = app_state.lock().await;
-            Ok(posts) => Ok(Json(posts)),
+        let cached: Option<Vec<Post>> = state
+            .cache
+            .get(String::from("posts:hot"))
+            .await
+            .unwrap_or(None);
+
+        if let Some(posts) = cached {
+            tracing::info!("grabbing hot posts from cache");
+            return Ok(Json(posts));
+        };
+
+        match PostsDatasource::get_hot(&state.database).await {
+            Ok(posts) => {
+                tracing::info!("grabbing hot posts from database");
+                if let p = &posts {
+                    let posts = p.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                String::from("posts:hot"),
+                                &posts,
+                                Some(Expiration::EX(5)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                };
+
+                Ok(Json(posts))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     // get posts that are featured
-    async fn get_featured_posts(State(pool): State<Pool<Postgres>>) -> impl IntoResponse {
+    async fn get_featured_posts(State(app_state): State<AppState>) -> impl IntoResponse {
-        match PostsDatasource::get_featured(&pool).await {
+        let mut state = app_state.lock().await;
-            Ok(posts) => Ok(Json(posts)),
+        let cached: Option<Vec<Post>> = state
+            .cache
+            .get(String::from("posts:featured"))
+            .await
+            .unwrap_or(None);
+
+        if let Some(posts) = cached {
+            tracing::info!("grabbing featured posts from cache");
+            return Ok(Json(posts));
+        };
+
+        match PostsDatasource::get_featured(&state.database).await {
+            Ok(posts) => {
+                tracing::info!("grabbing featured posts from database");
+                if let p = &posts {
+                    let posts = p.clone();
+                    let state = app_state.clone();
+
+                    tracing::info!("storing database data in cache");
+                    tokio::spawn(async move {
+                        let mut s = state.lock().await;
+                        let _ = s
+                            .cache
+                            .set(
+                                String::from("posts:featured"),
+                                &posts,
+                                Some(Expiration::EX(5)),
+                                None,
+                                false,
+                            )
+                            .await;
+                    });
+                };
+
+                Ok(Json(posts))
+            }
             Err(e) => Err((StatusCode::INTERNAL_SERVER_ERROR, e.to_string())),
         }
     }
 
     // get rss posts
-    async fn get_rss_posts(State(pool): State<Pool<Postgres>>) -> impl IntoResponse {
+    async fn get_rss_posts(State(app_state): State<AppState>) -> impl IntoResponse {
-        match PostsDatasource::get_all(&pool).await {
+        let state = app_state.lock().await;
+
+        match PostsDatasource::get_all(&state.database).await {
             Ok(posts) => {
                 let web_url = std::env::var("BASE_URI_WEB").expect("No environment variable found");
                 let mapped_posts: HashMap<String, Post> = posts
@@ -154,3 +369,46 @@ where
 {
     serializer.serialize_str(&date.unwrap().to_rfc3339())
 }
+
+pub fn deserialize_datetime<'de, D>(
+    deserializer: D,
+) -> Result<Option<chrono::DateTime<Utc>>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    struct DateTimeVisitor;
+
+    impl<'de> serde::de::Visitor<'de> for DateTimeVisitor {
+        type Value = Option<chrono::DateTime<Utc>>;
+
+        fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+            formatter.write_str("an ISO 8601 formatted date string or null")
+        }
+
+        fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
+        where
+            E: serde::de::Error,
+        {
+            match chrono::DateTime::parse_from_rfc3339(value) {
+                Ok(dt) => Ok(Some(dt.with_timezone(&Utc))),
+                Err(e) => Err(E::custom(format!("Failed to parse datetime: {}", e))),
+            }
+        }
+
+        fn visit_none<E>(self) -> Result<Self::Value, E>
+        where
+            E: serde::de::Error,
+        {
+            Ok(None)
+        }
+
+        fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
+        where
+            D: Deserializer<'de>,
+        {
+            deserializer.deserialize_str(self)
+        }
+    }
+
+    deserializer.deserialize_option(DateTimeVisitor)
+}

backend/public/src/state.rs

@@ -0,0 +1,78 @@
+use fred::interfaces::KeysInterface;
+use fred::{clients::Pool, prelude::*};
+use sqlx::PgPool;
+
+pub type AppState = std::sync::Arc<tokio::sync::Mutex<AppInternalState>>;
+
+pub struct AppInternalState {
+    pub database: sqlx::postgres::PgPool,
+    pub cache: Cache,
+}
+
+pub struct Cache {
+    pub inmem: Pool,
+}
+
+impl AppInternalState {
+    pub fn new(database: PgPool, cache: Pool) -> Self {
+        AppInternalState {
+            database,
+            cache: Cache { inmem: cache },
+        }
+    }
+}
+
+impl Cache {
+    pub async fn get<T>(&mut self, key: String) -> Result<Option<T>, Box<dyn std::error::Error>>
+    where
+        T: for<'de> serde::Deserialize<'de>,
+    {
+        if !self.inmem.is_connected() {
+            return Err(Box::new(std::io::Error::new(
+                std::io::ErrorKind::Other,
+                "Not connected to cache".to_string(),
+            )));
+        }
+
+        let value: Option<String> = self.inmem.get(&key).await?;
+
+        match value {
+            Some(json_str) => match serde_json::from_str::<T>(&json_str) {
+                Ok(deserialized) => Ok(Some(deserialized)),
+                Err(_) => Ok(None),
+            },
+            None => Ok(None),
+        }
+    }
+
+    pub async fn set<T>(
+        &mut self,
+        key: String,
+        contents: &T,
+        expiration: Option<Expiration>,
+        set_opts: Option<SetOptions>,
+        get: bool,
+    ) -> Result<(), Box<dyn std::error::Error>>
+    where
+        T: for<'de> serde::Deserialize<'de> + serde::Serialize,
+    {
+        if !self.inmem.is_connected() {
+            return Err(Box::new(std::io::Error::new(
+                std::io::ErrorKind::Other,
+                "Not connected to cache".to_string(),
+            )));
+        }
+
+        let json_string = serde_json::to_string(contents)?;
+        self.inmem
+            .set(key, json_string, expiration, set_opts, get)
+            .await?;
+
+        Ok(())
+    }
+
+    pub async fn del(&mut self, key: String) -> Result<(), Box<dyn std::error::Error>> {
+        self.inmem.del(key).await?;
+        Ok(())
+    }
+}

backend/task/README.md

@@ -0,0 +1,7 @@
+# Task scheduler
+
+also known as `task`
+
+## What is this?
+
+I don't know yet - hopefully this will be filled out soon.

database/README.md

@@ -1,6 +1,11 @@
 # Database
 
-You can set environment variables either through the command line, the Nix flake (if you are running nix/NixOS), _or_ the `.env` file
+You can set environment variables either through the command line, the Nix flake (if you are running nix/NixOS), _or_ the `.env` file.
+
+Uses the following data storing services:
+
+- PostgreSQL 16
+- Valkey 8.0.2 (or Redis, haven't tested)
 
 ## Create migration database