Here's what's going on with the noticed odd-good/even-bad behavior:
#!/usr/bin/perl
use common::sense;
use AnyEvent::HTTP;
use Data::Dumper;
sub do {
my $iter = shift;
my $cv = AnyEvent->condvar;
$cv->begin;
http_get
'https://imasheep.hurrdurr.org/category/about.html',
timeout => 2,
# out-comment to get the even/odd behavior
persistent => 0,
sub {
my ($body, $hdr) = @_;
say "$iter $hdr->{Status}";
unless ($hdr->{Status} == 200) {
warn Data::Dumper->Dump([$hdr],['hdr']);
}
$cv->end;
}
;
$cv->recv;
}
for (1..4) {
&do($_);
sleep(5);
}
The documentation for that 'persistent' reads as follows:
persistent => $boolean
Try to create/reuse a persistent connection. When this flag is set (default: true for idempotent
requests, false for all others), then "http_request" tries to re-use an existing (previously-created)
persistent connection to the host and, failing that, tries to create a new one.
Requests failing in certain ways will be automatically retried once, which is dangerous for non-
idempotent requests, which is why it defaults to off for them. The reason for this is because the bozos
who designed HTTP/1.1 made it impossible to distinguish between a fatal error and a normal connection
timeout, so you never know whether there was a problem with your request or not.
When reusing an existent connection, many parameters (such as TLS context) will be ignored. See the
"session" parameter for a workaround.
This default persistence for idempotent requests conflicts with your 5 seconds sleeps - and that's why only every second connection attempt succeeds.
Krambambuli
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