Sample

Compose nested sub-routers with onion middleware context propagation and centralized error handling in Hono

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CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17

Goal: Compose nested sub-routers with onion middleware context propagation and centralized error handling in Hono HOW
Packages: hono 4.13.2
Environment: node
Created: 2026-08-17T13:56:13Z

Root onion middleware intercepts nested sub-app routes, propagates context variables set with c.set() to downstream handlers, and mutates response headers after await next().
Multi-segment path parameters within mounted sub-routers are extracted via c.req.param() alongside inherited context variables.
Centralized app.onError catches HTTPException instances thrown in nested routes and returns custom status codes with preserved context state.
Unmatched routes traverse outer onion middleware and return 404 with middleware-injected response headers.

node 22 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17 · ed25519:d91480838ac982c9