From 87b85f7d3d0f96ee0cf3683336f5d667b4bbcb5d Mon Sep 17 00:00:00 2001
From: Jake Jarvis <jake@jarv.is>
Date: Wed, 22 Oct 2025 17:45:19 -0400
Subject: [PATCH] Add query transformation for non-English WHOIS servers,
 specifically for whois.jprs.jp (fixes #15)

---
 src/whois/client.test.ts | 37 +++++++++++++++++++++++++++++++++++++
 src/whois/client.ts      | 18 +++++++++++++++++-
 2 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/src/whois/client.test.ts b/src/whois/client.test.ts
index 2c5b829..4fc3c1f 100644
--- a/src/whois/client.test.ts
+++ b/src/whois/client.test.ts
@@ -13,3 +13,40 @@ describe("edge runtime behavior", () => {
     );
   });
 });
+
+describe("query transformation for non-English WHOIS servers", () => {
+  it("should append /e to queries for whois.jprs.jp", async () => {
+    // Mock net module to capture the query being sent
+    let capturedQuery = "";
+
+    vi.doMock("node:net", () => ({
+      createConnection: () => {
+        return {
+          on: (event: string, callback: (arg?: unknown) => void) => {
+            if (event === "connect") {
+              // Capture the query that will be written
+              setTimeout(() => callback(), 0);
+            } else if (event === "end") {
+              setTimeout(() => callback(), 10);
+            }
+          },
+          write: (data: string) => {
+            capturedQuery = data.replace(/\r\n$/, ""); // Strip CRLF
+          },
+          destroy: () => {},
+          setTimeout: () => {},
+        };
+      },
+    }));
+
+    const { whoisQuery } = await import("../whois/client");
+
+    try {
+      await whoisQuery("whois.jprs.jp", "hairtect.jp");
+    } catch {
+      // Query may fail since we're mocking, but we just want to check the query format
+    }
+
+    expect(capturedQuery).toBe("hairtect.jp/e");
+  });
+});
diff --git a/src/whois/client.ts b/src/whois/client.ts
index 40ceca4..e8d3826 100644
--- a/src/whois/client.ts
+++ b/src/whois/client.ts
@@ -7,6 +7,17 @@ export interface WhoisQueryResult {
   text: string;
 }
 
+/**
+ * Some WHOIS servers default to non-English responses. This mapping allows automatic
+ * query transformation to request English-only output for easier parsing.
+ *
+ * To add new servers: Add an entry with the hostname and transformation function:
+ *   "whois.example.org": (query) => `${query}/english`,
+ */
+const WHOIS_QUERY_TRANSFORMERS: Record<string, (query: string) => string> = {
+  "whois.jprs.jp": (query) => `${query}/e`, // Append /e for English-only response
+};
+
 /**
  * Perform a WHOIS query against an RFC 3912 server over TCP 43.
  * Returns the raw text and the server used.
@@ -19,8 +30,13 @@ export async function whoisQuery(
   const timeoutMs = options?.timeoutMs ?? DEFAULT_TIMEOUT_MS;
   const port = 43;
   const host = server.replace(/^whois:\/\//i, "");
+
+  // Transform query if server requires special formatting
+  const transformer = WHOIS_QUERY_TRANSFORMERS[host];
+  const transformedQuery = transformer ? transformer(query) : query;
+
   const text = await withTimeout(
-    queryTcp(host, port, query, options),
+    queryTcp(host, port, transformedQuery, options),
     timeoutMs,
     "WHOIS timeout",
   );