Made utility methods to work with HTTP body

src/utils/net/http-request-body.ts

@@ -0,0 +1,59 @@
+import { Blob, isBlob } from "./blob";
+import { FormData, isFormData } from "./form-data";
+import { isURLSearchParams } from "./query-string";
+
+/**
+ * Represents possible HTTP request body types.
+ */
+export type HttpRequestBody = string | Blob | Buffer | URLSearchParams | FormData | NodeJS.ReadableStream;
+
+/**
+ * Checks if the given value is one of the supported HTTP request body types.
+ *
+ * @param body - The value to check.
+ *
+ * @returns `true` if the value is a valid HTTP request body type; otherwise, `false`.
+ */
+export function isHttpRequestBody(body: unknown): body is HttpRequestBody {
+    return (
+        typeof body === "string" ||
+        isBlob(body) ||
+        Buffer.isBuffer(body) ||
+        isURLSearchParams(body) ||
+        isFormData(body) ||
+        isReadableStream(body)
+    );
+}
+
+/**
+ * Checks if the given value can be used as a streamable HTTP request body.
+ *
+ * @param body - The value to check.
+ *
+ * @returns `true` if the value can be used as a streamable HTTP request body; otherwise, `false`.
+ */
+export function isStreamableHttpRequestBody(body: unknown): body is Blob | Buffer | NodeJS.ReadableStream {
+    return (
+        isBlob(body) ||
+        Buffer.isBuffer(body) ||
+        isReadableStream(body)
+    );
+}
+
+/**
+ * Checks if the given value is a readable stream.
+ *
+ * @param stream - The value to check.
+ *
+ * @returns `true` if the value is a readable stream; otherwise, `false`.
+ */
+function isReadableStream(stream: unknown): stream is NodeJS.ReadableStream {
+    const s = stream as NodeJS.ReadableStream;
+    return (
+        s &&
+        typeof s.read === "function" &&
+        typeof s.pause === "function" &&
+        typeof s.resume === "function" &&
+        typeof s.setEncoding === "function"
+    );
+}