feat: lookup from Host header for default host

all replacements are now case-insensitive

README.md

@@ -68,7 +68,6 @@ The following keys are meaningful in this object:
 | `host_header`              | Override the hostname that is used as the `Host` header when connecting to the origin.                                                                                                                                                                      | The canonical host is used.                                                                             | `"news.example.org"`                          |
 | `host_ssl`                 | Override the hostname that is used for TLS SNI and for verification of the upstream's TLS certificate.                                                                                                                                                      | The canonical host is used.                                                                             | `"news.example.org"`                          |
 | `matomo_site_id`           | The site ID to use for Matomo tracking.                                                                                                                                                                                                                     | No tracking code is added to HTML pages.                                                                | `20`                                          |
-| `rewrite_case_insensitive` | Rewrite references to other domain names using a case-insensitive match. This requires the use of the PCRE engine which is approximately 10% of the speed of the Lua pattern matching engine, so only enable if required.                                   | Domains are matched based on the case in the pool mapping.                                              | `true`                                        |
 | `rewrite_disable`          | Disable content rewriting for this host. This disables both URL rewriting, and the addition of Matomo tracking code, but not the replacement of absolute links to the canonical hostname with relative links.                                               | Rewriting is enabled.                                                                                   | `true`                                        |
 
 Note: the default case applies when the key is omitted.

src/default.conf

@@ -1,6 +1,6 @@
 error_log /dev/stdout;
 
-lua_shared_dict jasima_cache 20m;
+lua_shared_dict jasima_cache 30m;
 lua_package_path "/opt/sitelen-tu/?.lua;;";
 
 lua_shared_dict auto_ssl 1m;
@@ -60,15 +60,15 @@ server {
         proxy_set_header Accept-Encoding "";
         proxy_set_header Host $jasima_host_header;
 
-        sub_filter_once off;
-        sub_filter_types text/html text/css text/xml application/javascript application/rss+xml application/atom+xml application/vnd.mpegurl application/x-mpegurl;
-        sub_filter 'http://$jasima_host' '/';
-        sub_filter 'https://$jasima_host' '/';
-        sub_filter '//$jasima_host' '/';
-        sub_filter 'REWRITE_JASIMA_HOST_PLACEHOLDER' $jasima_host;
-
         header_filter_by_lua_file /opt/sitelen-tu/header_filter.lua;
         body_filter_by_lua_file /opt/sitelen-tu/body_filter.lua;
+
+        sub_filter_once off;
+        sub_filter_types text/html text/css text/xml application/javascript application/json application/rss+xml application/atom+xml application/vnd.mpegurl application/x-mpegurl;
+        sub_filter 'http://$jasima_host' '';
+        sub_filter 'https://$jasima_host' '';
+        sub_filter '//$jasima_host' '';
+        sub_filter 'REWRITE_JASIMA_HOST_PLACEHOLDER' $jasima_host;
     }
 }
 

src/lua/body_filter.lua

@@ -27,7 +27,7 @@ local function rewrite_body(body)
     -- Rewrite links for assets and outbound links to other mirrored sites
     local pool_map = ngx.ctx.jasima_pool_map
     if pool_map then
-        body = body:gsub("//([a-zA-Z0-9%.%-]+%.[a-zA-Z0-9]+)/", utils.get_mirror)
+        body = body:gsub("//([%a%d%.-]+%.[%a%d-]+)/+", utils.get_mirror)
     end
     -- Add Matomo tracking code
     if ngx.ctx.jasima_config.matomo_site_id then
@@ -37,8 +37,8 @@ local function rewrite_body(body)
     -- Handle first party Tealium installations
     if ngx.ctx.jasima_host_tealium then
         local escaped_host = ngx.ctx.jasima_host_tealium:gsub("%.", "%%.")
-        body = body:gsub("(https:)??//" .. escaped_host .. "/", "/utag/" .. ngx.ctx.jasima_config.first_party_tealium.account .. "/")
-        body = body:gsub("//tags.tiqcdn.com/", "/")
+        body = body:gsub("https://" .. escaped_host .. "/+", "/utag/" .. ngx.ctx.jasima_config.first_party_tealium.account .. "/")
+        body = body:gsub("//tags.tiqcdn.com/+", "/")
         if ngx.var.jasima_host_connect == "tags.tiqcdn.com" and ngx.ctx.jasima_host_adobe then
             body, count = body:gsub([[return"http"%+%(a%.ssl%?"s":""%)%+"://"%+b%+"/b/ss/]], [[return"/b/ss/]])
             ngx.log(ngx.DEBUG, "Performing rewrite for Adobe Analytics in Tealium tag " .. count)
@@ -47,7 +47,7 @@ local function rewrite_body(body)
     -- Handle first party Adobe Analytics
     if ngx.ctx.jasima_host_adobe then
         local escaped_host = ngx.ctx.jasima_host_adobe:gsub("%.", "%%.")
-        body = body:gsub("(https:)??//" .. escaped_host .. "/", "/")
+        body = body:gsub("https://" .. escaped_host .. "/+", "/")
     end
     return body
 end

src/lua/config.lua

@@ -4,8 +4,32 @@ local redis = require "resty.redis"
 
 local _M = {}
 
+local function get_default_host(host)
+    local cache = ngx.shared.jasima_cache
+    local cache_key = "default:" .. host
+    local cached = cache:get(cache_key)
+    if cached then return cached end
+
+    local red = redis:new()
+    red:set_timeout(1000)
+    local ok, err = red:connect("redis", 6379)
+    if not ok then return nil, "Redis connect failed: " .. err end
+
+    local key = "jasima:default:" .. host
+    local res, err = red:get(key)
+    if not res or res == ngx.null then return nil, "No default in Redis" end
+
+    red:set_keepalive(10000, 100)
+
+    cache:set(cache_key, res, 60)
+    return res
+end
+
 function _M.get_jasima_host()
     local headers = ngx.req.get_headers()
+    if headers["Cf-Ray"] and headers["Host"] then
+        return get_default_host(headers["Host"])
+    end
     if headers["Jasima-Host"] then
         return headers["Jasima-Host"]
     end

src/lua/header_filter.lua

@@ -5,24 +5,25 @@ if ngx.ctx.jasima_config.rewrite_disable then
 end
 
 if ngx.header["Content-Type"] then
-    local content_type = ngx.header["Content-Type"]
+    local content_type = ngx.header["Content-Type"]:lower()
     if content_type:find("text/html") or
        content_type:find("text/css") or
        content_type:find("text/xml") or
        content_type:find("application/javascript") or
-       content_type:find("application/rss+xml") or
-       content_type:find("application/atom+xml") or
-       content_type:find("application/vnd.mpegurl") or
-       content_type:find("application/x-mpegurl") then
+       content_type:find("application/json") or
+       content_type:find("application/rss%+xml") or
+       content_type:find("application/atom%+xml") or
+       content_type:find("application/vnd%.mpegurl") or
+       content_type:find("application/x%-mpegurl") then
+        ngx.log(ngx.DEBUG, "Enabling rewrite due to content type " .. content_type)
         ngx.ctx.rewriting = true
-        ngx.header["Content-Length"] = nil
+        ngx.header["Content-Length"] = nil  -- We're rewriting the body so this has the wrong value if set
     end
 end
 
 if ngx.header["Location"] then
-    local pool_map = ngx.ctx.jasima_pool_map
-    if ngx.ctx.rewriting and pool_map then
+    if ngx.ctx.jasima_pool_map then
         local location = ngx.header["Location"]
-        ngx.header["Location"] = location:gsub("//([a-zA-Z0-9%.%-]+%.[a-zA-Z0-9]+)/", utils.get_mirror)
+        ngx.header["Location"] = location:gsub("//([%a%d%.-]+%.[%a%d-]+)/+", utils.get_mirror)
     end
 end

src/lua/utils.lua

@@ -75,6 +75,9 @@ end
 function _M.get_mirror(host)
     ngx.log(ngx.DEBUG, "Looking up mirror for " .. host)
     local host_lower = host:lower()
+    if host_lower == ngx.ctx.jasima_host then
+        return "//" .. host_lower .. "/"  -- This will get made relative by sub_filter later
+    end
     local mirror = ngx.ctx.jasima_pool_map[host_lower]
     return "//" .. (mirror or host) .. "/"
 end