[BUG] agent_url issue with ipv6 only Kubernetes

[NickStallman]

Bug description

It appears when using DDTrace in a IPv6 only environment, the agent url may be detected as invalid. Amazon AWS EKS now supports IPv6 only clusters

PHP version

7.4.30

Tracer version

0.73.0

Diagnostics and configuration

The DD_AGENT_HOST variable is set correctly to a IPv6 address of the DD Agent.

DD_AGENT_HOST=2a05:d01c:806:8003:xxxx:xxxx:d572:58be

This gets converted to the agent_url:

agent_url: http://2a05:d01c:806:8003:xxxx:xxxx:d572:58be:8126"

Which results in the agent_error:

URL using bad\/illegal format or missing URL

It should probably construct the url like this instead:

agent_url: http://[2a05:d01c:806:8003:xxxx:xxxx:d572:58be]:8126"

Output of phpinfo() (ddtrace >= 0.47.0)

DATADOG TRACER CONFIGURATION => {"date":"2022-07-25T02:20:37Z","os_name":"Linux lp-accounts-694f758f9c-dlcst 5.4.196-108.356.amzn2.x86_64 #1 SMP Thu May 26 12:49:47 UTC 2022 x86_64","os_version":"5.4.196-108.356.amzn2.x86_64","version":"0.73.0","lang":"php","lang_version":"7.4.21","env":"produk","enabled":true,"service":"lp-accounts","enabled_cli":false,"agent_url":"http:\/\/2a05:d01c:806:8003:xxxx:xxxx:d572:58be:8126","debug":false,"analytics_enabled":false,"sample_rate":1,"sampling_rules":[],"tags":[],"service_mapping":[],"distributed_tracing_enabled":true,"priority_sampling_enabled":true,"dd_version":"b6ec9edb","architecture":"x86_64","sapi":"cli","datadog.trace.request_init_hook":"\/opt\/datadog-php\/dd-trace-sources\/bridge\/dd_wrap_autoloader.php","open_basedir_configured":false,"uri_fragment_regex":null,"uri_mapping_incoming":null,"uri_mapping_outgoing":null,"auto_flush_enabled":false,"generate_root_span":true,"http_client_split_by_domain":true,"measure_compile_time":true,"report_hostname_on_root_span":false,"traced_internal_functions":null,"auto_prepend_file_configured":false,"integrations_disabled":"default","enabled_from_env":false,"opcache.file_cache":null,"agent_error":"URL using bad\/illegal format or missing URL"}

[bwoebi]

Hey @NickStallman,

I agree, this is not correct. As a workaround, use DD_TRACE_AGENT_URL="http://[2a05:d01c:806:8003:xxxx:xxxx:d572:58be]:8126". We will fix this issue soon.