id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
2221	log_format with escape=json doesn't encode $status correctly	silvpol@…		"When logging status code 000, the number is not encoded to just single 0, creating invalid JSON. The status needs to be numeric in Stackdriver so encoding as text is not possible as a workaround.
Not sure how to cause the 000 code, but this periodically shows up in the logs.

Logging config:
{{{
log_format proxy escape=json '{'
'""timestamp"":""$msec"",'
'""site"":""$host"",'
'""httpRequest"":{'
'""requestMethod"":""$request_method"",'
'""requestUrl"":""$request_uri"",'
'""requestSize"":""$request_length"",'
'""status"":$status,'
'""responseSize"":""$body_bytes_sent"",'
'""userAgent"":""$http_user_agent"",'
'""remoteIp"":""$remote_addr"",'
'""referer"":""$http_referer"",'
'""latency"":""${request_time}s""'
'},'
'""logging.googleapis.com/operation"":{'
'""id"":""$request_id"",'
'""producer"":""nginx""'
'},'
'""xff"":""$http_x_forwarded_for"",'
'""rtt"":$tcpinfo_rtt,'
'""proxy"":{'
'""connectionLatencies"":""$upstream_connect_time"",'
'""responseLatencies"":""$upstream_response_time"",'
'""user"":""$upstream_http_x_user_id""'
'}'
'}';
}}}

Example output:
{{{
{
  ""timestamp"": ""1617591631.057"",
  ""site"": ""example.com"",
  ""httpRequest"": {
    ""requestMethod"": ""GET"",
    ""requestUrl"": ""/test/wp-includes/wlwmanifest.xml"",
    ""requestSize"": ""511"",
    ""status"": 000,
    ""responseSize"": ""0"",
    ""userAgent"": ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"",
    ""remoteIp"": ""XX.XX.XX.XX"",
    ""referer"": """",
    ""latency"": ""37.362s""
  },
  ""logging.googleapis.com/operation"": {
    ""id"": ""a0d31a9b3f5dd16feeb6ee2925da3450"",
    ""producer"": ""nginx"",
    ""first"": true
  },
  ""xff"": ""XX.XX.XX.XX, XX.XX.XX.XX"",
  ""rtt"": 878
}
}}}

"	defect	closed	minor		nginx-module	1.17.x	invalid	log_format json		Linux 47acd776dd23 5.10.25-linuxkit #1 SMP Tue Mar 23 09:27:39 UTC 2021 x86_64 Linux	"nginx version: nginx/1.17.10
built by gcc 9.2.0 (Alpine 9.2.0) 
built with OpenSSL 1.1.1d  10 Sep 2019 (running with OpenSSL 1.1.1g  21 Apr 2020)
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid --lock-path=/var/run/nginx.lock --http-client-body-temp-path=/var/cache/nginx/client_temp --http-proxy-temp-path=/var/cache/nginx/proxy_temp --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp --http-scgi-temp-path=/var/cache/nginx/scgi_temp --with-perl_modules_path=/usr/lib/perl5/vendor_perl --user=nginx --group=nginx --with-compat --with-file-aio --with-threads --with-http_addition_module --with-http_auth_request_module --with-http_dav_module --with-http_flv_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_mp4_module --with-http_random_index_module --with-http_realip_module --with-http_secure_link_module --with-http_slice_module --with-http_ssl_module --with-http_stub_status_module --with-http_sub_module --with-http_v2_module --with-mail --with-mail_ssl_module --with-stream --with-stream_realip_module --with-stream_ssl_module --with-stream_ssl_preread_module --with-cc-opt='-Os -fomit-frame-pointer' --with-ld-opt=-Wl,--as-needed"