Add support for page cache using Redis

Author: bogdanpetrea

…host-conf.d/30-well-knonw-locations.conf …host-conf.d/30-well-known-locations.confphp/docker/templates/nginx-vhost-conf.d/30-well-knonw-locations.conf renamed to php/docker/templates/nginx-vhost-conf.d/30-well-known-locations.conf php/docker/templates/nginx-vhost-conf.d/30-well-knonw-locations.conf renamed to php/docker/templates/nginx-vhost-conf.d/30-well-known-locations.conf

@@ -0,0 +1,52 @@
+# vim: set ft=nginx:
+
+{{- if eq .Env.STACK_PAGE_CACHE_BACKEND "redis" }}
+location /.stack-cache-fetch {
+    internal;
+
+    set $redis_key $args;
+    redis_pass {{ default "localhost:6379" .Env.STACK_PAGE_CACHE_REDIS_HOST_PATH }};
+}
+
+location /.stack-cache-store {
+    internal;
+
+    set_unescape_uri $exptime $arg_exptime;
+    set_unescape_uri $key $arg_key;
+
+    redis2_query set $key $echo_request_body;
+    redis2_query expire $key $exptime;
+    redis2_pass {{ default "localhost:6379" .Env.STACK_PAGE_CACHE_REDIS_HOST_PATH }};
+}
+{{- end }}
+
+{{- if eq .Env.STACK_PAGE_CACHE_BACKEND "memcached" }}
+location = /.stack-cache-fetch {
+    internal;
+
+    set $memc_key $args;
+
+    memc_connect_timeout 500ms;
+    memc_read_timeout 500ms;
+    memc_ignore_client_abort on;
+
+    memc_pass {{ default "localhost:11211" .Env.STACK_PAGE_CACHE_MEMCACHED_HOST_PATH }};
+}
+
+
+location = /.stack-cache-store {
+    internal;
+
+    set_unescape_uri $exptime $arg_exptime;
+    set_unescape_uri $key $arg_key;
+
+    set $memc_key $key;
+    set $memc_exptime $exptime;
+
+    memc_connect_timeout 500ms;
+    memc_send_timeout 500ms;
+    memc_ignore_client_abort on;
+
+    memc_pass {{ default "localhost:11211" .Env.STACK_PAGE_CACHE_MEMCACHED_HOST_PATH }};
+}
+{{- end }}

php/docker/templates/nginx-vhost-conf.d/75-page-cache-locations.conf

@@ -5,6 +5,46 @@ location / {
 }
 
 location ~ \.php$ {
+    {{- if .Env.STACK_PAGE_CACHE_BACKEND }}
+    set $skip_cache 0;
+
+    # POST requests and urls with a query string should always go to PHP
+    if ($request_method = POST) {
+        set $skip_cache 1;
+    }
+    if ($query_string != "") {
+        set $skip_cache 1;
+    }
+
+    # Don't cache uris containing the following segments
+    if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|/feed/|index.php|sitemap(_index)?.xml") {
+        set $skip_cache 1;
+    }
+
+    # Don't use the cache for logged in users or recent commenters
+    if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_no_cache|wordpress_logged_in") {
+        set $skip_cache 1;
+    }
+
+    set $key {{ default "nginx-cache:https$request_method$host$request_uri" .Env.STACK_PAGE_CACHE_KEY_PATTERN }};
+    try_files $uri =404;
+
+    srcache_fetch_skip $skip_cache;
+    srcache_store_skip $skip_cache;
+    srcache_store_statuses {{ default "200 301 302" .Env.STACK_PAGE_CACHE_STORE_STATUSES }};
+
+    # https://github.com/openresty/srcache-nginx-module#srcache_response_cache_control
+    srcache_response_cache_control off;
+
+    set_escape_uri $escaped_key $key;
+
+    srcache_fetch GET /.stack-cache-fetch $key;
+    srcache_store PUT /.stack-cache-store key=$escaped_key&exptime={{ default "360" .Env.STACK_PAGE_CACHE_EXPIRE_SECONDS | atoi }};
+
+    more_set_headers 'x-cache-fetch $srcache_fetch_status';
+    more_set_headers 'x-cache-store $srcache_store_status';
+    {{- end }}
+
     fastcgi_pass   $upstream;
     fastcgi_read_timeout {{ max 60 (add 10 (default "30" .Env.PHP_REQUEST_TIMEOUT | atoi)) }};
     fastcgi_index  index.php;