More verbosity and delayed retries

[Stef-33560]

This PR adds

• more retries, with delay
  For a reason that I can't explain when has_v1_mirror is true, some downloads fails, it seems that retrying immediately doesn't helps to recover everytime the things. Adding a fixed pause (i.e. : 1 second in commit 1066162) does not seems to be always sufficient. Calming more and more down the little 🐰 forces him to gather things much better ! 😜
• verbosity (while using -v)

Output show between between brackets show the number of retries.

• time ./mirror --v2 -v, from empty folder, started 2021-06-12T09:29PM UTC,

Seen at the end of the process :

....MMR[1]R[1]R[1]R[1]R[1]R[1]R[2]R[2]R[2]R[2]R[2]R[2]R[3]R[3]R[3]R[3]R[3]R[3]R[4]R[4]R[4]R[4]R[4]R[4]R[5]R[5]R[5]R[5]R[5]R[5]R[6]R[6]R[6]R[6]R[6]R[6]R[7]R[7]R[7]R[7]R[7]R[7]R[8]R[8]R[8]R[8]R[8]R[8]R[9]R[9]R[9]R[9]R[9]R[9]R[10]R[10]R[10]R[10]R[10]R[10]??????
Downloaded 611665 files
real 33m23,535s
user 9m41,809s
sys 2m5,659s

• time ./mirror.php --resync -v started at 2021-06-1210:16PMUTC
  Seen at the end of the process :

---R[1]R[1]R[1]R[1]R[1]R[1]R[2]R[2]R[2]R[2]R[2]R[2]R[3]R[3]R[3]R[3]R[3]R[3]R[4]R[4]R[4]R[4]R[4]R[4]R[5]R[5]R[5]R[5]R[5]R[5]R[6]R[6]R[6]R[6]R[6]R[6]R[7]R[7]R[7]R[7]R[7]R[7]R[8]R[8]R[8]
R[8]R[8]R[8]R[9]R[9]R[9]R[9]R[9]R[9]R[10]R[10]R[10]R[10]R[10]R[10]??????
Downloaded 611667 files

real 27m6,411s
user 7m5,421s
sys 1m5,743s

The mirror is fully operationnal

composer config repos.packagist composer https://mirror-composer.lan/
composer require drush/drush

[...]
14 package suggestions were added by new dependencies, use composer suggest to see details.

[Seldaek]

This is not necessary IMO. It adds longer sleep but with the addition of 10 retries we anyway get 10x2sec sleep which should really be more than enough for everything to sync up upstream.

[Stef-33560]

Without this exponentiel timeout time, even with 10 times, my mirror fails.
I don't know why, maybe an issue with my ISP, with CloudFlare or something like that ?

I retried with another ISP ; results :

git clone https://github.com/composer/mirror/
cat mirror.config.php

<?php

return [
    // directory where metadata files will get saved
    'target_dir' => './mymirror',
    // user agent describing your mirror node, if possible include domain name of mirror, and a contact email address
    'user_agent' => 'Just testing mirror script'/* TODO Mirror for foo.com (mycontact@example.org) */,
    // source repository URL
    'repo_url' => 'https://repo.packagist.org',
    // source repository hostname (optional, will guess from repo_url)
    //'repo_hostname' => 'repo.packagist.org',
    // source API URL
    'api_url' => 'https://repo.packagist.org',
    // how many times the script will run the mirroring step before exiting
    'iterations' => 1,
    // how many seconds to wait between mirror runs
    'iteration_interval' => 5,
    // set this to false if you do not run the --v1 mirror job, to ensure that the v2 will then take care of syncing packages.json
    'has_v1_mirror' => false,
];

./mirror.php --v2 -v

[...] lots of M [...]
[...] plenty of EEEEEEE [...]
Fatal error: Uncaught Symfony\Component\HttpClient\Exception\TransportException: Timeout was reached for "https://repo.packagist.org/p2/muxtor/yii2-pkk5-component.json". in /home/steph/composer-mirror/vendor/symfony/http-client/Response/CurlResponse.php:317

Result : 3.6Gb

With my PR, with the same config, no EEEE:

[...] lots of M [...]
[1]R[1]R[1]R[1]R[1]R[1]R[1]R[1]R[2]R[2]R[2]R[2]R[2]R[2]R[2]R[2]R[3]R[3]R[3]R[3]R[3]R[3]R[3]R[3]R[4]R[4]R[4]R[4]R[4]R[4]R[4]R[4]R[5]R[5]R[5]R[5]R[5]R[5]R[5]R[5]R[6]R[6]R[6]R[6]R[6]R[6]R[6]R[6]R[7]R[7]R[7]R[7]R[7]R[7]R[7]R[7]R[8]R[8]R[8]R[8]R[8]R[8]R[8]R[8]R[9]R[9]R[9]R[9]R[9]R[9]R[9]R[9]R[10]R[10]R[10]R[10]R[10]R[10]R[10]R[10]????????

Result : 6.2Gb