How to use source map of esbuild with SEA

[louis222220]

I have build an application with esbuild and Node SEA. The application works.

However, after I build with source-map option of esbuild. The final application is just as the same, instead of logging with source-map.

The following is my script in Dockerfile:

# ...

RUN npx --yes esbuild src/app.js --sourcemap --bundle --platform=node --packages=external --outfile=app-out.cjs
# or --sourcemap=inline

RUN echo "const { createRequire } = require('node:module'); require = createRequire(__filename);" >> tmp-app-out.cjs && cat app-out.cjs >> tmp-app-out.cjs && mv tmp-app-out.cjs app-out.cjs
RUN node --experimental-sea-config sea-config.json && cp $(command -v node) app && npx --yes postject app NODE_SEA_BLOB sea-prep.blob --sentinel-fuse NODE_SEA_FUSE_fce680ab2cc467b6e072b8b5df1996b2
CMD ["./app"]

My directory:

.
├── Dockerfile
├── app-out.cjs
├── app-out.cjs.map
├── package-lock.json
├── package.json
├── sea-config.json
└── src
    └── app.js

It works fine if I keep the file app-out.cjs in the directory. But the functionality of source-map disappears if I delete the bundled source file.
The condition conflict with my purpose because I want to delivery only the application without source code.

rm app-out.cjs

./app
Express server listening on port 3000
(do something and throw an error)

Error: my error
    at app-out.cjs:6464:9
    at Layer.handle [as handle_request] (/usr/app/node_modules/express/lib/router/layer.js:95:5)
    at next (/usr/app/node_modules/express/lib/router/route.js:137:13)
    at Route.dispatch (/usr/app/node_modules/express/lib/router/route.js:112:3)
    at Layer.handle [as handle_request] (/usr/app/node_modules/express/lib/router/layer.js:95:5)
    at /usr/app/node_modules/express/lib/router/index.js:281:22
    at Function.process_params (/usr/app/node_modules/express/lib/router/index.js:335:12)
    at next (/usr/app/node_modules/express/lib/router/index.js:275:10)
    at cors (/usr/app/node_modules/cors/lib/index.js:188:7)
    at /usr/app/node_modules/cors/lib/index.js:224:17

Could anyone give me some idea or advice?

[joyeecheung]

There is currently no VFS/FS hooks support in Node.js in general. Effectively the SEA supports a main script and a list of assets, and it's up to the user how they can map the bundled assets and redirect fs calls (internal or user-land) to it (currently, they can only monkey-patch fs, until proper fs hooks are agreed upon and implemented by someone : #43). Internally, not being able to locate the file inside the SEA (as there's no VFS support) would just lead to missing source maps.

[louis222220]

Thank for your answer!
In conclusion, source-map is not a solution that meets my expectation.
Some keyword is beyond my current knowledge, but I will try to understand them.