Add file uploads

Good luck getting them, though

.gitignore

@@ -1,3 +1,5 @@
 /target
 /.direnv
 /config.toml
+/temp
+/files

Cargo.lock

@@ -807,11 +807,15 @@ dependencies = [
  "axum",
  "eyre",
  "figment",
+ "futures-util",
+ "hex",
  "http",
  "serde",
+ "sha2",
  "sqlx",
  "thiserror",
  "tokio",
+ "tokio-util",
  "tower-http",
  "tracing",
  "tracing-subscriber",
@@ -1684,6 +1688,19 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "tokio-util"
+version = "0.7.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5419f34732d9eb6ee4c3578b7989078579b7f039cbbb9ca2c4da015749371e15"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-sink",
+ "pin-project-lite",
+ "tokio",
+]
+
 [[package]]
 name = "toml"
 version = "0.8.8"

Cargo.toml

@@ -7,11 +7,15 @@ edition = "2021"
 axum = { version = "0.6.20", default-features = false, features = ["http1", "json", "macros", "matched-path", "tokio", "tower-log", "tracing"] }
 eyre = "0.6.8"
 figment = { version = "0.10.11", features = ["env", "toml"] }
+futures-util = { version = "0.3.30", default-features = false }
+hex = "0.4.3"
 http = "0.2.9"
 serde = { version = "1.0.189", features = ["derive"] }
+sha2 = "0.10.8"
 sqlx = { version = "0.7.3", features = ["runtime-tokio", "postgres", "uuid"] }
 thiserror = "1.0.51"
-tokio = { version = "1.33.0", features = ["rt-multi-thread", "macros"] }
+tokio = { version = "1.33.0", features = ["rt-multi-thread", "macros", "fs", "io-std"] }
+tokio-util = { version = "0.7.10", features = ["io"] }
 tower-http = { version = "0.4.4", features = ["trace"] }
 tracing = "0.1.37"
 tracing-subscriber = "0.3.17"

src/app/api/files.rs

@@ -0,0 +1,92 @@
+use std::path::PathBuf;
+
+use axum::{
+    extract::{BodyStream, State},
+    routing::post,
+    Json, Router,
+};
+use futures_util::TryStreamExt;
+use serde::Serialize;
+use sha2::{Digest, Sha256};
+use sqlx::PgPool;
+use tokio::{
+    fs::{self, File},
+    io,
+};
+use tokio_util::io::StreamReader;
+use tracing::{error, field, info, instrument};
+use ulid::Ulid;
+
+use crate::error::AppError;
+
+pub fn router(db: PgPool) -> Router {
+    Router::new().route("/", post(upload_file)).with_state(db)
+}
+
+#[derive(Debug, Serialize)]
+struct UploadedFile {
+    id: Ulid,
+    hash: String,
+}
+
+#[instrument(skip(body))]
+async fn upload_file(
+    State(_db): State<PgPool>,
+    body: BodyStream,
+) -> Result<Json<UploadedFile>, AppError> {
+    let id_temp = Ulid::new();
+    let file_path_temp = PathBuf::from("temp").join(id_temp.to_string());
+    let mut hasher = Sha256::new();
+
+    {
+        let mut file_temp = File::create(&file_path_temp).await?;
+
+        let better_body = body
+            .inspect_ok(|b| hasher.update(b))
+            .map_err(|err| io::Error::new(io::ErrorKind::Other, err));
+        let mut reader = StreamReader::new(better_body);
+
+        if let Err(err) = io::copy(&mut reader, &mut file_temp).await {
+            error!(
+                err = field::display(&err),
+                file_path = field::debug(&file_path_temp),
+                "failed to copy file, removing",
+            );
+
+            drop(file_temp);
+            if let Err(err) = fs::remove_file(file_path_temp).await {
+                error!(
+                    err = field::display(err),
+                    "failed to remove failed upload file",
+                );
+            }
+
+            return Err(err.into());
+        }
+    }
+
+    let hash = hasher.finalize();
+    let hash_hex = hex::encode(hash);
+    let file_path_hash = PathBuf::from("files").join(&hash_hex);
+
+    if fs::try_exists(&file_path_hash).await? {
+        info!(hash = hash_hex, "file already exists");
+        if let Err(err) = fs::remove_file(&file_path_temp).await {
+            error!(err = field::display(&err), "failed to remove temp file");
+        }
+    } else if let Err(err) = fs::rename(&file_path_temp, &file_path_hash).await {
+        error!(err = field::display(&err), "failed to move finished file");
+        if let Err(err) = fs::remove_file(&file_path_temp).await {
+            error!(
+                err = field::display(&err),
+                "failed to remove file after failed rename",
+            );
+        }
+        return Err(err.into());
+    }
+
+    Ok(Json(UploadedFile {
+        id: id_temp,
+        hash: hash_hex,
+    }))
+}

src/app/api/mod.rs

@@ -1,8 +1,11 @@
+mod files;
 mod links;
 
 use axum::Router;
 use sqlx::PgPool;
 
 pub fn router(db: PgPool) -> Router {
-    Router::new().nest("/links", links::router(db))
+    Router::new()
+        .nest("/files", files::router(db.clone()))
+        .nest("/links", links::router(db))
 }

src/error.rs

@@ -14,6 +14,8 @@ pub enum AppError {
     #[error("database error")]
     Database(#[from] sqlx::Error),
     #[error(transparent)]
+    Io(#[from] std::io::Error),
+    #[error(transparent)]
     Other(#[from] eyre::Report),
 }
 
@@ -33,6 +35,11 @@ impl IntoResponse for AppError {
                 "A database error has occured",
             )
                 .into_response(),
+            Self::Io(_) => (
+                StatusCode::INTERNAL_SERVER_ERROR,
+                "An I/O error has occured",
+            )
+                .into_response(),
             Self::Other(err) => (
                 StatusCode::INTERNAL_SERVER_ERROR,
                 format!("An error has occured:\n{err:?}"),