Automatically gzip Wasm binaries

[lastmjs]

dfx 0.14.0 introduced automatic binary optimization from wasm-opt with a new optimize field in the dfx.json. This is great, but the wasm-opt might not be enough. gzip may be necessary after the wasm-opt pass, but it is difficult to retrieve the binary after optimization as it's stored rather opaquely in .dfx (actually is that true? I think it might be optimizing the binary in-place using the path to the binary from dfx.json).

It would be great if gzip could be done automatically in addition to wasm-opt, to have even more optimization tools available easily to developers.

[adamspofford-dfinity]

This would have to be an explicit field, as gzipping the canister is meaningful on the replica's end - the reported canister module hash is that of the gz file, not of the uncompressed wasm file.

[lastmjs]

Sounds good to me, just like we have the optimize field, we could have a gzip field. If they are both specified, optimization would happen first and then gzip. And gzip perhaps should allow different settings just like optimize, i.e. -9.

[kentosugama]

Just to clarify, the binary is optimized in place

[ericswanson-dfinity]

gzip: true canister field added in dfx 0.14.1