Analytics request loader and game version validation (#6064)

* Analytics request loader and game version validation

* tweak agents

* factor tags into its own util

* lock cache refresh to avoid cache stampede

* Make analytics fields opptional

apps/labrinth/src/routes/internal/admin.rs

@@ -11,7 +11,9 @@ use crate::search::SearchBackend;
 use crate::util::date::get_current_tenths_of_ms;
 use crate::util::error::Context;
 use crate::util::guards::admin_key_guard;
+use crate::util::tags::valid_download_tags;
 use actix_web::{HttpRequest, HttpResponse, patch, post, web};
+use eyre::eyre;
 use serde::Deserialize;
 use std::collections::HashMap;
 use std::net::Ipv4Addr;
@@ -40,9 +42,9 @@ pub struct DownloadBody {
 /// [`DOWNLOAD_META_HEADER`] header.
 #[derive(Debug, Clone, Deserialize)]
 pub struct DownloadMeta {
-    pub reason: DownloadReason,
-    pub game_version: String,
-    pub loader: String,
+    pub reason: Option<DownloadReason>,
+    pub game_version: Option<String>,
+    pub loader: Option<String>,
 }
 
 pub const DOWNLOAD_META_HEADER: &str = "modrinth-download-meta";
@@ -139,6 +141,27 @@ pub async fn count_download(
             None
         };
 
+    if let Some(meta) = &meta {
+        let valid_download_tags = valid_download_tags(&pool, &redis)
+            .await
+            .wrap_internal_err("failed to fetch valid download tags")?;
+        if let Some(loader) = &meta.loader
+            && !valid_download_tags.loaders.contains(loader)
+        {
+            return Err(ApiError::Request(eyre!(
+                "invalid download loader specified"
+            )));
+        }
+
+        if let Some(game_version) = &meta.game_version
+            && !valid_download_tags.game_versions.contains(game_version)
+        {
+            return Err(ApiError::Request(eyre!(
+                "invalid download game version specified"
+            )));
+        }
+    }
+
     let download = Download {
         recorded: get_current_tenths_of_ms(),
         domain: url.host_str().unwrap_or_default().to_string(),
@@ -176,13 +199,19 @@ pub async fn count_download(
             .collect(),
         reason: meta
             .as_ref()
-            .map(|m| m.reason.to_string())
+            .and_then(|m| m.reason.as_ref())
+            .map(|s| s.to_string())
             .unwrap_or_default(),
         game_version: meta
             .as_ref()
-            .map(|m| m.game_version.clone())
+            .and_then(|m| m.game_version.as_ref())
+            .map(|s| s.to_string())
+            .unwrap_or_default(),
+        loader: meta
+            .as_ref()
+            .and_then(|m| m.loader.as_ref())
+            .map(|s| s.to_string())
             .unwrap_or_default(),
-        loader: meta.as_ref().map(|m| m.loader.clone()).unwrap_or_default(),
     };
     trace!("added download {download:#?}");