Track HiveGrid Cloud planning reference

hivegrid-cloud/apps/web/app/utils/server/IpUtils.ts

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+import isIP from "is-ip";
+
+/**
+ * This is the list of headers, in order of preference, that will be used to
+ * determine the client's IP address.
+ */
+const headerNames = Object.freeze([
+  "X-Client-IP",
+  "CF-Connecting-IP",
+  "X-Forwarded-For",
+  "Fly-Client-IP",
+  "Fastly-Client-Ip",
+  "True-Client-Ip",
+  "X-Real-IP",
+  "X-Cluster-Client-IP",
+  "X-Forwarded",
+  "Forwarded-For",
+  "Forwarded",
+  "DO-Connecting-IP" /** Digital ocean app platform */,
+] as const);
+
+/**
+ * Get the IP address of the client sending a request.
+ *
+ * It receives the Request object or the headers object and use it to get the
+ * IP address from one of the following headers in order.
+ *
+ * - X-Client-IP
+ * - X-Forwarded-For
+ * - Fly-Client-IP
+ * - CF-Connecting-IP
+ * - Fastly-Client-Ip
+ * - True-Client-Ip
+ * - X-Real-IP
+ * - X-Cluster-Client-IP
+ * - X-Forwarded
+ * - Forwarded-For
+ * - Forwarded
+ * - DO-Connecting-IP
+ *
+ * If the IP address is valid, it will be returned. Otherwise, null will be
+ * returned.
+ *
+ * If the header values contains more than one IP address, the first valid one
+ * will be returned.
+ */
+export function getClientIPAddress(headers: Headers): string | null;
+export function getClientIPAddress(request: Request): string | null;
+export function getClientIPAddress(requestOrHeaders: Request | Headers): string | null {
+  const headers = requestOrHeaders instanceof Request ? requestOrHeaders.headers : requestOrHeaders;
+
+  let ipAddress = headerNames
+    .flatMap((headerName) => {
+      let value = headers.get(headerName);
+      if (headerName === "Forwarded") {
+        return parseForwardedHeader(value);
+      }
+      if (!value?.includes(",")) return value;
+      return value.split(",").map((ip) => ip.trim());
+    })
+    .find((ip) => {
+      if (ip === null) return false;
+      return isIP(ip);
+    });
+
+  return ipAddress ?? null;
+}
+
+function parseForwardedHeader(value: string | null): string | null {
+  if (!value) return null;
+  for (let part of value.split(";")) {
+    if (part.startsWith("for=")) return part.slice(4);
+    continue;
+  }
+  return null;
+}