Httpd server access log parser
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The only supported format now is this one:
log_format main '$remote_addr - $remote_user [$time_local] $status '
'"$request" $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for" '
'rt="$request_time" ut="$upstream_response_time" '
'us="$upstream_status" ua="$upstream_addr" '
'cs="$upstream_cache_status"';