Wrap Hono request body parsing methods

Author: timokoessler

library/sources/Hono.test.ts

@@ -94,6 +94,21 @@ function getApp() {
     return c.json(getContext());
   });
 
+  app.post("/json", async (c) => {
+    const json = await c.req.json();
+    return c.json(getContext());
+  });
+
+  app.post("/text", async (c) => {
+    const text = await c.req.text();
+    return c.json(getContext());
+  });
+
+  app.post("/form", async (c) => {
+    const form = await c.req.parseBody();
+    return c.json(getContext());
+  });
+
   app.on(["GET"], ["/user", "/user/blocked"], (c) => {
     return c.json(getContext());
   });
@@ -140,7 +155,7 @@ t.test("it adds context from request for GET", opts, async (t) => {
 });
 
 t.test("it adds JSON body to context", opts, async (t) => {
-  const response = await getApp().request("/", {
+  const response = await getApp().request("/json", {
     method: "POST",
     headers: {
       "content-type": "application/json",
@@ -153,12 +168,12 @@ t.test("it adds JSON body to context", opts, async (t) => {
     method: "POST",
     body: { title: "test" },
     source: "hono",
-    route: "/",
+    route: "/json",
   });
 });
 
 t.test("it adds form body to context", opts, async (t) => {
-  const response = await getApp().request("/", {
+  const response = await getApp().request("/form", {
     method: "POST",
     headers: {
       "content-type": "application/x-www-form-urlencoded",
@@ -171,12 +186,12 @@ t.test("it adds form body to context", opts, async (t) => {
     method: "POST",
     body: { title: "test" },
     source: "hono",
-    route: "/",
+    route: "/form",
   });
 });
 
 t.test("it adds text body to context", opts, async (t) => {
-  const response = await getApp().request("/", {
+  const response = await getApp().request("/text", {
     method: "POST",
     headers: {
       "content-type": "text/plain",
@@ -189,12 +204,12 @@ t.test("it adds text body to context", opts, async (t) => {
     method: "POST",
     body: "test",
     source: "hono",
-    route: "/",
+    route: "/text",
   });
 });
 
 t.test("it adds xml body to context", opts, async (t) => {
-  const response = await getApp().request("/", {
+  const response = await getApp().request("/text", {
     method: "POST",
     headers: {
       "content-type": "application/xml",
@@ -207,7 +222,7 @@ t.test("it adds xml body to context", opts, async (t) => {
     method: "POST",
     body: "<test>test</test>",
     source: "hono",
-    route: "/",
+    route: "/text",
   });
 });
 

library/sources/hono/contextFromRequest.ts

@@ -2,40 +2,12 @@ import type { Context as HonoContext } from "hono";
 import { Context } from "../../agent/Context";
 import { buildRouteFromURL } from "../../helpers/buildRouteFromURL";
 import { getIPAddressFromRequest } from "../../helpers/getIPAddressFromRequest";
-import { isJsonContentType } from "../../helpers/isJsonContentType";
 import { parse } from "../../helpers/parseCookies";
 import { getRemoteAddress } from "./getRemoteAddress";
 
 export async function contextFromRequest(c: HonoContext): Promise<Context> {
   const { req } = c;
 
-  let body = undefined;
-  const contentType = req.header("content-type");
-  if (contentType) {
-    if (isJsonContentType(contentType)) {
-      try {
-        body = await req.json();
-      } catch {
-        // Ignore
-      }
-    } else if (contentType.startsWith("application/x-www-form-urlencoded")) {
-      try {
-        body = await req.parseBody();
-      } catch {
-        // Ignore
-      }
-    } else if (
-      contentType.includes("text/plain") ||
-      contentType.includes("xml")
-    ) {
-      try {
-        body = await req.text();
-      } catch {
-        // Ignore
-      }
-    }
-  }
-
   const cookieHeader = req.header("cookie");
 
   return {
@@ -44,7 +16,7 @@ export async function contextFromRequest(c: HonoContext): Promise<Context> {
       headers: req.header(),
       remoteAddress: getRemoteAddress(c),
     }),
-    body: body,
+    body: undefined,
     url: req.url,
     headers: req.header(),
     routeParams: req.param(),

library/sources/hono/wrapRequestBodyParsing.ts

@@ -0,0 +1,31 @@
+import type { Context } from "hono";
+import { getContext, updateContext } from "../../agent/Context";
+
+export function wrapRequestBodyParsing(req: Context["req"]) {
+  req.parseBody = wrapRequestHandler(req.parseBody);
+  req.json = wrapRequestHandler(req.json);
+  req.text = wrapRequestHandler(req.text);
+}
+
+type BodyParseFunctions =
+  | Context["req"]["parseBody"]
+  | Context["req"]["json"]
+  | Context["req"]["text"];
+
+export function wrapRequestHandler<T extends BodyParseFunctions>(
+  handler: T
+): T {
+  return async function () {
+    // @ts-expect-error No type for arguments
+    const returnValue = await handler.apply(this, arguments);
+
+    if (returnValue) {
+      const context = getContext();
+      if (context) {
+        updateContext(context, "body", returnValue);
+      }
+    }
+
+    return returnValue as ReturnType<T>;
+  } as T;
+}

library/sources/hono/wrapRequestHandler.ts

@@ -1,6 +1,7 @@
 import type { Handler, MiddlewareHandler } from "hono";
 import { runWithContext } from "../../agent/Context";
 import { contextFromRequest } from "./contextFromRequest";
+import { wrapRequestBodyParsing } from "./wrapRequestBodyParsing";
 
 export function wrapRequestHandler(
   handler: Handler | MiddlewareHandler
@@ -9,6 +10,8 @@ export function wrapRequestHandler(
     const context = await contextFromRequest(c);
 
     return await runWithContext(context, async () => {
+      wrapRequestBodyParsing(c.req);
+
       return await handler(c, next);
     });
   };