Fix TypeError in strict mode

[unreadable]

Using polka as a handler for firebase cloud functions will cause the following error to be thrown: "TypeError: Cannot set property path of # which has only a getter".

Basically, "strict mode" won't allow changing the request path since it got no setter implemented.
These changes fix it.

[ghost]

this fix breaks polka (see travis) as req.path is used in handling requests for basenames

[unreadable]

this fix breaks polka (see travis) as req.path is used in handling requests for basenames

@devcat I see. Will fix it asap.

[ghost]

that doesn't fix it code requires req.path to be set and that's what you are trying to remove

[codecov-io]

Codecov Report

Merging #86 into master will decrease coverage by 0.95%.
The diff coverage is 75%.

@@            Coverage Diff             @@
##           master      #86      +/-   ##
==========================================
- Coverage     100%   99.04%   -0.96%     
==========================================
  Files           4        4              
  Lines         102      105       +3     
==========================================
+ Hits          102      104       +2     
- Misses          0        1       +1

Impacted Files	Coverage Δ
packages/polka/index.js	98.46% <75%> (-1.54%)	⬇️

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[unreadable]

that doesn't fix it code requires req.path to be set and that's what you are trying to remove

@devcat Yeah, figured it out. Tests seem to pass now, will checkout for code coverage as well.

[lukeed]

Ah, thanks. I don't use Polka in GCP functions because they have a lot of stuff built-in to the platform, so much of Polka (or anything) ends up being redundant.

The use of try/catch & Object.defineProperty is actually detrimental to the execution performance. 😕 Can you change it to my suggestion below? It should still work with the strict-mode getter.

if (!req.path) req.path = info.pathname;

Thanks~!

[unreadable]

@lukeed thanks for the sugestion, but unfortunately it doesn't pass the tests. What about removing the try/catch block and using this instead?

Object.defineProperty(req, 'path', {
	writeable: false,
	value: info.pathname
});

[lukeed]

Aye, my bad, that was an oversight. It won't update the req.path as it traverses down into sub-applications or middleware groups (since req.path is now defined).

It's O.dP that is slow – that's what I'm trying to avoid. The try/catch makes it a bit slower because it happens as an else-clause, effectively.

I may have to rethink this a little bit. Does it work correctly within a GCP function with your original changes?

[unreadable]

@lukeed I see. We're using firebase cloud functions, but I think they are the same as google cloud ones. I managed to make it run using the try/catch + o.dP in the end, also looked to lift the "strict mode" so the error won't be thrown anymore. I'll be looking for other workarounds as well.

[lukeed]

Yeah, they're the same thing :)

Cool – curious, but what's setting strict mode in the first place?

[unreadable]

@lukeed by inspecting the modules, seems that n_m/firebase-function, which takes my handler, uses strict mode. Haven’t found a way to disable it so far.

[lukeed]

Ah right, yeah. That would make sense.

I'll play with this tonight, but again, I personally don't use Polka inside my GCP functions because it'd be pointless. Express is already "baked in" to the firebase-functions library, so running Polka on top of it just duplicates the work & functionality that's already there and unavoidable.