Honor 429 HTTP Code / Retry-After header

[john-hascall]

The command line client's --retry option should recognize and honor the 429 HTTP status return and the accompanying 'Retry-After' header.

Affects all versions, but I happen to be running:

curl 7.29.0 (x86_64-redhat-linux-gnu) libcurl/7.29.0 NSS/3.28.4 zlib/1.2.7 libidn/1.28 libssh2/1.4.3
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp scp sftp smtp smtps telnet tftp
Features: AsynchDNS GSS-Negotiate IDN IPv6 Largefile NTLM NTLM_WB SSL libz unix-sockets

on:

Linux 3.10.0-514.26.2.el7.x86_64 #1 SMP Fri Jun 30 05:26:04 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

[bagder]

I reasonable suggestion methinks, even if that's a very rarely used response code and header...

[john-hascall]

I think it is relatively common in *Something*-as-a-Service REST APIs. I know that at least three we interact with (Infoblox, Okta, Workday) will return it if we exceed their transactions-per-time-period limits. John

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On Fri, Apr 19, 2019 at 10:33 AM Daniel Stenberg ***@***.***> wrote: I reasonable suggestion methinks, even if that's a very rarely used response code and header... — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#3794 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFTWUXQWSO5H2L2QZ63RPETPRHQ4PANCNFSM4HHEKFXA> .

[bagder]

I want to address this issue after #3804 has gone in, just to save me from having to do double work.

[wmark]

At least one server written in Golang does sent this. It's used when it runs out of file descriptors.

Another sensible use is in anything that runs in the cloud, hits a resource limit (clouds are made of rigid boxes), and cold-start times are known.

[bagder]

It seems basically no browser supports it:

https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After#Browser_compatibility

[john-hascall]

That fits with what I’ve seen, which is a Retry-After header on a HTTP 429 reply from HTTPS REST API servers. I’ve not seen it on the kind of pages you would point a browser at. John John Hascall IT Services Iowa State Univ.

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On Aug 6, 2019, at 3:25 AM, Daniel Stenberg ***@***.***> wrote: It seems basically no browser supports it: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After#Browser_compatibility — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[john-hascall]

Thanks, this looks really great. John

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On Wed, Aug 7, 2019 at 7:49 AM Daniel Stenberg ***@***.***> wrote: Closed #3794 <#3794> via 640b973 <640b973> . — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#3794?email_source=notifications&email_token=AFTWUXQIUANWULQNNFPN33LQDLAEDA5CNFSM4HHEKFXKYY3PNVWWK3TUL52HS4DFWZEXG43VMVCXMZLOORHG65DJMZUWGYLUNFXW5KTDN5WW2ZLOORPWSZGOS5SIRKI#event-2539948201>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFTWUXSSETKHRV5FAPMT4K3QDLAEDANCNFSM4HHEKFXA> .