improve ws protocol struct naming and documentation

crates/ws_protocol/src/incoming/scrape.rs

@@ -0,0 +1,32 @@
+use serde::{Deserialize, Serialize};
+
+use crate::common::*;
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ScrapeRequest {
+    /// Always "scrape"
+    pub action: ScrapeAction,
+    /// Info hash or info hashes
+    ///
+    /// Notes from reference implementation:
+    /// - If omitted, scrape for all torrents, apparently
+    /// - Accepts a single info hash or an array of info hashes
+    #[serde(rename = "info_hash")]
+    pub info_hashes: Option<ScrapeRequestInfoHashes>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(untagged)]
+pub enum ScrapeRequestInfoHashes {
+    Single(InfoHash),
+    Multiple(Vec<InfoHash>),
+}
+
+impl ScrapeRequestInfoHashes {
+    pub fn as_vec(self) -> Vec<InfoHash> {
+        match self {
+            Self::Single(info_hash) => vec![info_hash],
+            Self::Multiple(info_hashes) => info_hashes,
+        }
+    }
+}