Add rate limit telemetry plugin

Is not enabled as it is not wired up to anything yet

Author: JustinGrote

src/api/rateLimitTelemetry.ts

@@ -0,0 +1,50 @@
+import {Octokit} from "@octokit/core";
+import {EventEmitter} from "vscode";
+
+// Exported variables to track rate limits
+export interface RateLimit {
+  remaining: number | null;
+  limit: number | null;
+  reset: Date | null;
+  used: number | null;
+}
+
+export const rateLimit: RateLimit = {
+  remaining: null,
+  limit: null,
+  reset: null,
+  used: null
+};
+
+const rateLimitUpdatedEvent = new EventEmitter<RateLimit>();
+export const onRateLimitUpdated = rateLimitUpdatedEvent.event;
+
+/**
+ * Octokit plugin to track GitHub API rate limits
+ */
+export const rateLimitTelemetryPlugin = (octokit: Octokit) => {
+  octokit.hook.wrap("request", async (request, options) => {
+    const response = await request(options);
+
+    // Extract rate limit information from headers
+    if (response.headers) {
+      const remaining = response.headers["x-ratelimit-remaining"];
+      const limit = response.headers["x-ratelimit-limit"];
+      const reset = response.headers["x-ratelimit-reset"];
+      const used = response.headers["x-ratelimit-used"];
+
+      // Update exported variables if headers are present
+      if (remaining) rateLimit.remaining = parseInt(String(remaining));
+      if (limit) rateLimit.limit = parseInt(String(limit));
+      if (reset) rateLimit.reset = new Date(parseInt(String(reset)) * 1000);
+      if (used) rateLimit.used = parseInt(String(used));
+    }
+    rateLimitUpdatedEvent.fire(rateLimit);
+
+    return response;
+  });
+
+  return {
+    ratelimit: rateLimit
+  };
+};