[OE-core] FETCHCMD drop breaks build when append is used (from patch b259bd31eb)

[Andre McCurdy]

On Sat, Aug 31, 2019 at 1:24 PM Andre McCurdy <armccurdy at gmail.com> wrote:
>
> On Sat, Aug 31, 2019 at 11:07 AM Andrey Zhizhikin <andrey.z at gmail.com> wrote:
> > On Sat, Aug 31, 2019 at 2:18 PM Adrian Bunk <bunk at stusta.de> wrote:
> > > Disallowing appends could cause huge problems for a user or layer that
> > > has to append local options (e.g. proxy) building a recipe like libedit
> > > that has to change the User-Agent.
>
> Clearly we need to have a solution for libedit. I don't see it's
> related to user or layer specific issues of setting a password or a
> proxy though.
>
> There seem to be three independent cases where appending to the
> fetcher commands in bitbake.conf has been used:
>
> 1) Setting usernames/passwords for private mirrors, sstate servers,
> etc. For that I believe the recommended solution is .netrc. Not only
> is putting passwords on the command line a bad idea in general, but it
> also won't work consistently for fetchers where download() and
> checkstatus() are implemented differently - e.g. for wget, download()
> calls wget (and therefore respects FETCHCMD_wget) but checkstatus() is
> implemented directly in python (and ignores FETCHCMD_wget completely).
> To see the effects, try setting up a password protected http or https
> sstate server... it will work if you put your credentials in .netrc
> but not if you add them to FETCHCMD_wget.
>
> 2) Configuring a proxy server for users behind a firewall. For that I
> believe the recommended solution is the various *_proxy environment
> variables?
>
> 3) Forcing a custom User-Agent. I don't know what the best solution is
> here but it feels like the wget fetcher should either handle this
> internally (e.g. set a more compatible User-Agent by default?
> Automatic retries with various User-Agents?) or provide a documented
> API which specifically sets the User-Agent in cases where the default
> really does need to be over-ridden.
>
> In the end the bitbake fetchers are abstractions and if users need to
> force their own options directly into the final command line (ie
> bypassing the abstraction) then it suggests the abstraction is
> incomplete. It feels like a slippery slope if we start to encourage or
> rely on doing that.

It looks like the User-Agent workaround for libedit might not be
needed any more anyway...

  wget http://thrysoee.dk/editline/libedit-20190324-3.1.tar.gz

works fine for me ( User-Agent: Wget/1.17.1 (linux-gnu) )