Game Version types, indexing, and bugfixes (#91)

* Add types to game_versions, allow filtering by version type

- Fixes an issue with version numbers in the initial mod indexing
  queue
- Modifies the /api/v1/categories/game_versions route to take an
  optional query parameter `type` to filter the listed game versions
- Creating tags is now idempotent
- Creating game_versions now requires a JSON body that specifies
  the version type

* Implement automatic indexing of new Minecraft versions

It's currently set to run every 6 hours and isn't configurable; we
could add config for it, but it doesn't seem likely to be rate
limited or have issues with frequency.

src/scheduler.rs

@@ -28,3 +28,106 @@ impl Drop for Scheduler {
         self.arbiter.stop();
     }
 }
+
+use log::{info, warn};
+
+pub fn schedule_versions(
+    scheduler: &mut Scheduler,
+    pool: sqlx::Pool<sqlx::Postgres>,
+    skip_initial: bool,
+) {
+    // Check mojang's versions every 6 hours
+    let version_index_interval = std::time::Duration::from_secs(60 * 60 * 6);
+
+    let mut skip = skip_initial;
+    scheduler.run(version_index_interval, move || {
+        let pool_ref = pool.clone();
+        let local_skip = skip;
+        if skip {
+            skip = false;
+        }
+        async move {
+            if local_skip {
+                return;
+            }
+            info!("Indexing game versions list from Mojang");
+            let result = update_versions(&pool_ref).await;
+            if let Err(e) = result {
+                warn!("Version update failed: {}", e);
+            }
+            info!("Done indexing game versions");
+        }
+    });
+}
+
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum VersionIndexingError {
+    #[error("Network error while updating game versions list: {0}")]
+    NetworkError(#[from] reqwest::Error),
+    #[error("Database error while updating game versions list: {0}")]
+    DatabaseError(#[from] crate::database::models::DatabaseError),
+}
+
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+struct InputFormat<'a> {
+    // latest: LatestFormat,
+    versions: Vec<VersionFormat<'a>>,
+}
+#[derive(Deserialize)]
+struct VersionFormat<'a> {
+    id: String,
+    #[serde(rename = "type")]
+    type_: std::borrow::Cow<'a, str>,
+}
+
+async fn update_versions(pool: &sqlx::Pool<sqlx::Postgres>) -> Result<(), VersionIndexingError> {
+    let input = reqwest::get("https://launchermeta.mojang.com/mc/game/version_manifest.json")
+        .await?
+        .json::<InputFormat>()
+        .await?;
+
+    let mut skipped_versions_count = 0u32;
+
+    for version in input.versions.into_iter() {
+        let name = version.id;
+        if !name
+            .chars()
+            .all(|c| c.is_ascii_alphanumeric() || "-_.".contains(c))
+        {
+            // We'll deal with these manually
+            skipped_versions_count += 1;
+            continue;
+        }
+
+        let type_ = match &*version.type_ {
+            "release" => "release",
+            "snapshot" => "snapshot",
+            "old_alpha" => "alpha",
+            "old_beta" => "beta",
+            _ => "other",
+        };
+
+        crate::database::models::categories::GameVersion::builder()
+            .version(&name)?
+            .version_type(type_)?
+            .insert(pool)
+            .await?;
+    }
+
+    if skipped_versions_count > 0 {
+        // This will currently always trigger due to 1.14 pre releases
+        // and the shareware april fools update. We could set a threshold
+        // that accounts for those versions and update it whenever we
+        // manually fix another version.
+        warn!(
+            "Skipped {} game versions; check for new versions and add them manually",
+            skipped_versions_count
+        );
+    }
+
+    Ok(())
+}