Initial shared instances backend (#3800)

* Create base shared instance migration and initial routes

* Fix build

* Add version uploads

* Add permissions field for shared instance users

* Actually use permissions field

* Add "public" flag to shared instances that allow GETing them without authorization

* Add the ability to get and list shared instance versions

* Add the ability to delete shared instance versions

* Fix build after merge

* Secured file hosting (#3784)

* Remove Backblaze-specific file-hosting backend

* Added S3_USES_PATH_STYLE_BUCKETS

* Remove unused file_id parameter from delete_file_version

* Add support for separate public and private buckets in labrinth::file_hosting

* Rename delete_file_version to delete_file

* Add (untested) get_url_for_private_file

* Remove url field from shared instance routes

* Remove url field from shared instance routes

* Use private bucket for shared instance versions

* Make S3 environment variables fully separate between public and private buckets

* Change file host expiry for shared instances to 180 seconds

* Fix lint

* Merge shared instance migrations into a single migration

* Replace shared instance owners with Ghost instead of deleting the instance

apps/labrinth/src/routes/v3/shared_instance_version_creation.rs

@@ -0,0 +1,200 @@
+use crate::auth::get_user_from_headers;
+use crate::database::models::shared_instance_item::{
+    DBSharedInstance, DBSharedInstanceUser, DBSharedInstanceVersion,
+};
+use crate::database::models::{
+    DBSharedInstanceId, DBSharedInstanceVersionId,
+    generate_shared_instance_version_id,
+};
+use crate::database::redis::RedisPool;
+use crate::file_hosting::{FileHost, FileHostPublicity};
+use crate::models::ids::{SharedInstanceId, SharedInstanceVersionId};
+use crate::models::pats::Scopes;
+use crate::models::shared_instances::{
+    SharedInstanceUserPermissions, SharedInstanceVersion,
+};
+use crate::queue::session::AuthQueue;
+use crate::routes::ApiError;
+use crate::routes::v3::project_creation::UploadedFile;
+use crate::util::ext::MRPACK_MIME_TYPE;
+use actix_web::http::header::ContentLength;
+use actix_web::web::Data;
+use actix_web::{HttpRequest, HttpResponse, web};
+use bytes::BytesMut;
+use chrono::Utc;
+use futures_util::StreamExt;
+use hex::FromHex;
+use sqlx::{PgPool, Postgres, Transaction};
+use std::sync::Arc;
+
+const MAX_FILE_SIZE: usize = 500 * 1024 * 1024;
+const MAX_FILE_SIZE_TEXT: &str = "500 MB";
+
+pub fn config(cfg: &mut web::ServiceConfig) {
+    cfg.route(
+        "shared-instance/{id}/version",
+        web::post().to(shared_instance_version_create),
+    );
+}
+
+#[allow(clippy::too_many_arguments)]
+pub async fn shared_instance_version_create(
+    req: HttpRequest,
+    pool: Data<PgPool>,
+    payload: web::Payload,
+    web::Header(ContentLength(content_length)): web::Header<ContentLength>,
+    redis: Data<RedisPool>,
+    file_host: Data<Arc<dyn FileHost + Send + Sync>>,
+    info: web::Path<(SharedInstanceId,)>,
+    session_queue: Data<AuthQueue>,
+) -> Result<HttpResponse, ApiError> {
+    if content_length > MAX_FILE_SIZE {
+        return Err(ApiError::InvalidInput(format!(
+            "File size exceeds the maximum limit of {MAX_FILE_SIZE_TEXT}"
+        )));
+    }
+
+    let mut transaction = pool.begin().await?;
+    let mut uploaded_files = vec![];
+
+    let result = shared_instance_version_create_inner(
+        req,
+        &pool,
+        payload,
+        content_length,
+        &redis,
+        &***file_host,
+        info.into_inner().0.into(),
+        &session_queue,
+        &mut transaction,
+        &mut uploaded_files,
+    )
+    .await;
+
+    if result.is_err() {
+        let undo_result = super::project_creation::undo_uploads(
+            &***file_host,
+            &uploaded_files,
+        )
+        .await;
+        let rollback_result = transaction.rollback().await;
+
+        undo_result?;
+        if let Err(e) = rollback_result {
+            return Err(e.into());
+        }
+    } else {
+        transaction.commit().await?;
+    }
+
+    result
+}
+
+#[allow(clippy::too_many_arguments)]
+async fn shared_instance_version_create_inner(
+    req: HttpRequest,
+    pool: &PgPool,
+    mut payload: web::Payload,
+    content_length: usize,
+    redis: &RedisPool,
+    file_host: &dyn FileHost,
+    instance_id: DBSharedInstanceId,
+    session_queue: &AuthQueue,
+    transaction: &mut Transaction<'_, Postgres>,
+    uploaded_files: &mut Vec<UploadedFile>,
+) -> Result<HttpResponse, ApiError> {
+    let user = get_user_from_headers(
+        &req,
+        pool,
+        redis,
+        session_queue,
+        Scopes::SHARED_INSTANCE_VERSION_CREATE,
+    )
+    .await?
+    .1;
+
+    let Some(instance) = DBSharedInstance::get(instance_id, pool).await? else {
+        return Err(ApiError::NotFound);
+    };
+    if !user.role.is_mod() && instance.owner_id != user.id.into() {
+        let permissions = DBSharedInstanceUser::get_user_permissions(
+            instance_id,
+            user.id.into(),
+            pool,
+        )
+        .await?;
+        if let Some(permissions) = permissions {
+            if !permissions
+                .contains(SharedInstanceUserPermissions::UPLOAD_VERSION)
+            {
+                return Err(ApiError::CustomAuthentication(
+                    "You do not have permission to upload a version for this shared instance.".to_string()
+                ));
+            }
+        } else {
+            return Err(ApiError::NotFound);
+        }
+    }
+
+    let version_id =
+        generate_shared_instance_version_id(&mut *transaction).await?;
+
+    let mut file_data = BytesMut::new();
+    while let Some(chunk) = payload.next().await {
+        let chunk = chunk.map_err(|_| {
+            ApiError::InvalidInput(
+                "Unable to parse bytes in payload sent!".to_string(),
+            )
+        })?;
+
+        if file_data.len() + chunk.len() <= MAX_FILE_SIZE {
+            file_data.extend_from_slice(&chunk);
+        } else {
+            file_data
+                .extend_from_slice(&chunk[..MAX_FILE_SIZE - file_data.len()]);
+            break;
+        }
+    }
+
+    let file_data = file_data.freeze();
+    let file_path = format!(
+        "shared_instance/{}.mrpack",
+        SharedInstanceVersionId::from(version_id),
+    );
+
+    let upload_data = file_host
+        .upload_file(
+            MRPACK_MIME_TYPE,
+            &file_path,
+            FileHostPublicity::Private,
+            file_data,
+        )
+        .await?;
+
+    uploaded_files.push(UploadedFile {
+        name: file_path,
+        publicity: upload_data.file_publicity,
+    });
+
+    let sha512 = Vec::<u8>::from_hex(upload_data.content_sha512).unwrap();
+
+    let new_version = DBSharedInstanceVersion {
+        id: version_id,
+        shared_instance_id: instance_id,
+        size: content_length as u64,
+        sha512,
+        created: Utc::now(),
+    };
+    new_version.insert(transaction).await?;
+
+    sqlx::query!(
+        "UPDATE shared_instances SET current_version_id = $1 WHERE id = $2",
+        new_version.id as DBSharedInstanceVersionId,
+        instance_id as DBSharedInstanceId,
+    )
+    .execute(&mut **transaction)
+    .await?;
+
+    let version: SharedInstanceVersion = new_version.into();
+    Ok(HttpResponse::Created().json(version))
+}