feat(node): Add an instrumentation interface for Hono (#17366)

This PR introduces the scaffolding for Sentry’s tracing integration with
[Hono](https://hono.dev/) by adding interface-only implementations and
wiring needed to verify the overall approach before filling in the
tracing logic.

## Summary

- Adds a new Hono Instrumentation (OpenTelemetry-based) which patches
Hono route and middleware APIs.
- Provides a honoIntegration exported via defineIntegration, plus an
instrumentHono guard using generateInstrumentOnce.
- Introduces minimal, vendored Hono types required for patching, and
enums for consistent attribute naming.

## Intent & scope

- Implemented interfaces only to validate the design direction.
The goal is to confirm the wrapping points, attribute schema, and
initialization flow before we add any span creation, context
propagation, or attribute setting.
- If this approach looks good, the next step is to ship a patch that
implements the route handler tracing.
That follow-up will include span start/finish, setting
hono.type/hono.name, request path/method extraction, and trace context
propagation.
- No tests added in this PR because it only introduces the interface and
structure. Tests will land together with the first functional
instrumentation patch.

## Rationale

There is an existing Hono OTel package
([@hono/otel](https://www.npmjs.com/package/@hono/otel)), but it
currently lacks several features we need for a robust Sentry
integration—especially middleware instrumentation and Sentry-specific
integration points (e.g., seamless correlation with Sentry
transactions/spans and future Sentry error handler wiring).
Given these gaps, we’re proceeding with an in-repo implementation
tailored for Sentry’s needs.

## Related Issue

#15260

Author: Karibash

packages/node/src/integrations/tracing/hono/index.ts

@@ -0,0 +1,35 @@
+import type { IntegrationFn } from '@sentry/core';
+import { defineIntegration } from '@sentry/core';
+import { generateInstrumentOnce } from '@sentry/node-core';
+import { HonoInstrumentation } from './instrumentation';
+
+const INTEGRATION_NAME = 'Hono';
+
+export const instrumentHono = generateInstrumentOnce(INTEGRATION_NAME, () => new HonoInstrumentation());
+
+const _honoIntegration = (() => {
+  return {
+    name: INTEGRATION_NAME,
+    setupOnce() {
+      instrumentHono();
+    },
+  };
+}) satisfies IntegrationFn;
+
+/**
+ * Adds Sentry tracing instrumentation for [Hono](https://hono.dev/).
+ *
+ * If you also want to capture errors, you need to call `setupHonoErrorHandler(app)` after you set up your Hono server.
+ *
+ * For more information, see the [hono documentation](https://docs.sentry.io/platforms/javascript/guides/hono/).
+ *
+ * @example
+ * ```javascript
+ * const Sentry = require('@sentry/node');
+ *
+ * Sentry.init({
+ *   integrations: [Sentry.honoIntegration()],
+ * })
+ * ```
+ */
+export const honoIntegration = defineIntegration(_honoIntegration);

packages/node/src/integrations/tracing/hono/instrumentation.ts

@@ -0,0 +1,84 @@
+import { InstrumentationBase, InstrumentationNodeModuleDefinition } from '@opentelemetry/instrumentation';
+import type { HandlerInterface, Hono, HonoInstance, MiddlewareHandlerInterface, OnHandlerInterface } from './types';
+
+const PACKAGE_NAME = '@sentry/instrumentation-hono';
+const PACKAGE_VERSION = '0.0.1';
+
+/**
+ * Hono instrumentation for OpenTelemetry
+ */
+export class HonoInstrumentation extends InstrumentationBase {
+  public constructor() {
+    super(PACKAGE_NAME, PACKAGE_VERSION, {});
+  }
+
+  /**
+   * Initialize the instrumentation.
+   */
+  public init(): InstrumentationNodeModuleDefinition[] {
+    return [
+      new InstrumentationNodeModuleDefinition('hono', ['>=4.0.0 <5'], moduleExports => this._patch(moduleExports)),
+    ];
+  }
+
+  /**
+   * Patches the module exports to instrument Hono.
+   */
+  private _patch(moduleExports: { Hono: Hono }): { Hono: Hono } {
+    // eslint-disable-next-line @typescript-eslint/no-this-alias
+    const instrumentation = this;
+
+    moduleExports.Hono = class HonoWrapper extends moduleExports.Hono {
+      public constructor(...args: unknown[]) {
+        super(...args);
+
+        instrumentation._wrap(this, 'get', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'post', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'put', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'delete', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'options', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'patch', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'all', instrumentation._patchHandler());
+        instrumentation._wrap(this, 'on', instrumentation._patchOnHandler());
+        instrumentation._wrap(this, 'use', instrumentation._patchMiddlewareHandler());
+      }
+    };
+    return moduleExports;
+  }
+
+  /**
+   * Patches the route handler to instrument it.
+   */
+  private _patchHandler(): (original: HandlerInterface) => HandlerInterface {
+    return function (original: HandlerInterface) {
+      return function wrappedHandler(this: HonoInstance, ...args: unknown[]) {
+        // TODO: Add OpenTelemetry tracing logic here
+        return original.apply(this, args);
+      };
+    };
+  }
+
+  /**
+   * Patches the 'on' handler to instrument it.
+   */
+  private _patchOnHandler(): (original: OnHandlerInterface) => OnHandlerInterface {
+    return function (original: OnHandlerInterface) {
+      return function wrappedHandler(this: HonoInstance, ...args: unknown[]) {
+        // TODO: Add OpenTelemetry tracing logic here
+        return original.apply(this, args);
+      };
+    };
+  }
+
+  /**
+   * Patches the middleware handler to instrument it.
+   */
+  private _patchMiddlewareHandler(): (original: MiddlewareHandlerInterface) => MiddlewareHandlerInterface {
+    return function (original: MiddlewareHandlerInterface) {
+      return function wrappedHandler(this: HonoInstance, ...args: unknown[]) {
+        // TODO: Add OpenTelemetry tracing logic here
+        return original.apply(this, args);
+      };
+    };
+  }
+}

packages/node/src/integrations/tracing/hono/types.ts

@@ -0,0 +1,50 @@
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/request.ts#L30
+export type HonoRequest = {
+  path: string;
+};
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/context.ts#L291
+export type Context = {
+  req: HonoRequest;
+};
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/types.ts#L36C1-L36C39
+export type Next = () => Promise<void>;
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/types.ts#L73
+export type Handler = (c: Context, next: Next) => Promise<Response> | Response;
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/types.ts#L80
+export type MiddlewareHandler = (c: Context, next: Next) => Promise<Response | void> | Response | void;
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/types.ts#L109
+export type HandlerInterface = {
+  (...handlers: (Handler | MiddlewareHandler)[]): HonoInstance;
+  (path: string, ...handlers: (Handler | MiddlewareHandler)[]): HonoInstance;
+};
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/types.ts#L1071
+export type OnHandlerInterface = {
+  (method: string | string[], path: string | string[], ...handlers: (Handler | MiddlewareHandler)[]): HonoInstance;
+};
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/types.ts#L679
+export type MiddlewareHandlerInterface = {
+  (...handlers: MiddlewareHandler[]): HonoInstance;
+  (path: string, ...handlers: MiddlewareHandler[]): HonoInstance;
+};
+
+// Vendored from: https://github.com/honojs/hono/blob/855e5b1adbf685bf4b3e6b76573aa7cb0a108d04/src/hono-base.ts#L99
+export interface HonoInstance {
+  get: HandlerInterface;
+  post: HandlerInterface;
+  put: HandlerInterface;
+  delete: HandlerInterface;
+  options: HandlerInterface;
+  patch: HandlerInterface;
+  all: HandlerInterface;
+  on: OnHandlerInterface;
+  use: MiddlewareHandlerInterface;
+}
+
+export type Hono = new (...args: unknown[]) => HonoInstance;