OK, new question on `python_requirements`: one of our desired lambda functions uses

pydantic

which insists on lugging along its 60MB (!) of binaries. I would like to install it as

--no-binary

if possible, which supposedly gets it down to about 6mb, much nice to fit under lambda requirements. I would ordinarily, apparently, put the line

--no-binary=pydantic

in the

requirements.txt

in addition to

pydantic==1.8.1

, but I've tried a few permutations and I think pants just doesn't like that sort of thing. Is there a way to do it with

python_requirement_library

or some such?

Hmm, are you seeing errors, or is the

--no-binary

behavior just being ignored? cc @enough-analyst-54434 for thoughts.

It's being ignored, we discard all the

--foo

options when parsing a requirements.txt because

pkg_resources.Requirement

does not understand it, and Pex won't understand them when passed as an argument. Only works in the requirements.txt file and with pex's

-r req.txt

Part of the prework for adding per-tool lockfiles is to start respecting things like

--no-binary

and

--hash

from requirements.txt files, given that we must support

--hash

. https://docs.google.com/document/d/1If8wGowEpYaehGd_CQ8KxwFSydU1Q8UdpLr0i36NROk/edit# That prework will land in the next week if all goes to plan @echoing-farmer-15630 as part of 2.6. We can't cherry-pick to 2.5 unfortunately, it's too breaking of a change. 2.6 in general is getting an enormous revamp of 3rd party dependencies (see that google doc)

More context on Eric's explanation: 1. For legacy reasons, Pants parses requirements into Requirement objects even though its now only a middle-man and could just be shuffling along requirement strings to Pex. 2. Pex ~= Pip for all things requirement related and Pip takes many options affecting requirement resolution only in requirements files (like --hash). Others, like -

-no-binary <comma-sep-packages>

that some Pip subcommands accept on the CLI, must be passed via requirements files when using Pex. Since Pants does not pass along requirements files to Pex (it could only do this in limited scenarios anyhow and in general will need to generate a synthetic requirements file), there is currently no avenue to pass this stuff. And that gets to the prework Eric mentioned.