[libexec] improve libexec

* be aware of where it is stored
* resolve lua scripts relative to libexec
* no need to change directory
* forward log level to resty binary
* respect APICAST_DIR env

gateway/libexec/run

@@ -1,10 +1,24 @@
-#!/usr/bin/env sh
+#!/usr/bin/env perl
+use Cwd qw(getcwd abs_path);
+use File::Basename qw(dirname basename);
+use File::Temp qw(tempfile);
+use File::Spec::Functions qw(catfile);
 
-ssl=$(mktemp -q)
+my $libexec = abs_path(dirname(abs_path(__FILE__)));
+my $apicast = $ENV{APICAST_DIR} || catfile($libexec, '..');
 
-certificate=${SSL_CERT_FILE:-"$(pwd)/conf/ca-bundle.crt"}
+my $ssl_cert_file = $ENV{SSL_CERT_FILE} || catfile($apicast, 'conf', 'ca-bundle.crt');
+my $lua_file = catfile($libexec, basename(__FILE__) . '.lua');
+my $errlog_level = $ENV{APICAST_LOG_LEVEL} || 'warn';
 
-echo "lua_ssl_verify_depth 5;" >> "${ssl}"
-echo "lua_ssl_trusted_certificate \"${certificate}\";" >> "${ssl}"
+my ($fh, $ssl_conf_file) = tempfile();
 
-exec resty --http-include "${ssl}" "libexec/$(basename "$0").lua" "$@"
+print $fh <<_NGINX_;
+lua_ssl_verify_depth 5;
+lua_ssl_trusted_certificate "${ssl_cert_file}";
+_NGINX_
+
+exec 'resty',
+    '--errlog-level', $errlog_level,
+    '--http-include', $ssl_conf_file,
+    $lua_file, @ARGV;

gateway/src/apicast/configuration_loader.lua

@@ -90,8 +90,9 @@ end
 -- Cosocket API is not available in the init_by_lua* context (see more here: https://github.com/openresty/lua-nginx-module#cosockets-not-available-everywhere)
 -- For this reason a new process needs to be started to download the configuration through 3scale API
 function _M.run_external_command(cmd, cwd)
-  local config, err, code = util.system(format('cd %s && libexec/%s',
-    cwd or env.get('TEST_NGINX_APICAST_PATH') or '.',
+  local config, err, code = util.system(format('cd %s && %s/libexec/%s',
+    cwd or  '.',
+    env.get('APICAST_DIR') or env.get('TEST_NGINX_APICAST_PATH') or '.',
     cmd or 'boot'))
 
   -- Try to read the file in current working directory before changing to the prefix.