use USE_STAGING_BINARIES splicing PIP_WHEEL_URL

[duanhongyi]

No description provided.

[edmorley]

Hi! Thank you for the PR :-)

Could you describe the motivation for this change? (For example what's the use-case and is this for Heroku or something else?) Generally a PR should always have a description that describes the "why" that isn't necessarily apparent from the "what" of the diff itself. There's a good guide to commit messages here that may be of interest :-)
https://chris.beams.io/posts/git-commit/

If this is something that is accepted, it will also:

• need some tests
• need to use a different approach for the env var, depending on whether this is for Heroku use or not (since app env vars aren't automatically set in the build enviroment; buildpacks have to load ENV_DIR etc)

Many thanks!

[edmorley]

Oops forgot to also say - if you make further changes to the PR, please add them to this one - no need to make a new PR each time :-)

[edmorley]

@duanhongyi Hi! I don't suppose you saw my questions above? :-)

[duanhongyi]

I'm really sorry. I just came back from my vacation.

The motivation for this RP is simple. In my opinion, in USE_STAGING_BINARIES should contain the PIP installation script.

[edmorley]

The motivation for this RP is simple. In my opinion, in USE_STAGING_BINARIES should contain the PIP installation script.

@duanhongyi Hi! Thank you for the reply. However I'm still not sure what the motivation is? For example:

• what are you trying to do with the buildpack
• why does the current implementation make that hard
• what are you doing to work around it in the meantime
• how does this change make that easier?

Without more details we won't be able to accept the change.

[edmorley]

@duanhongyi Hi! I suspect your use-case might be fixed by #1085 (which I needed to do for other reasons, but conveniently makes custom S3 URLs for the pip case easier too).