commit: refactor onion_to_dns to be smarter, use it more, and trap body rewrites in POST only

templates.d/bounce.sh.txt

@@ -2,5 +2,6 @@
 # eotk (c) 2017 Alec Muffett
 cd %PROJECT_DIR% || exit 1
 sh %PROJECT_DIR%/stop.sh
+sleep 1
 sh %PROJECT_DIR%/start.sh
 exit 0

templates.d/nginx.conf.txt

@@ -274,6 +274,9 @@ http {
         return result
       end
       local o, num, errs = ngx.re.gsub(i, "(%LEFT_TLD_RE%)([a-z2-7]{16}(?:[a-z2-7]{40})?\\.onion)\\b", o_to_d_lookup, "io")
+      if errs == nil and num == 0 then
+        return i -- nothing was changed, so return the original
+      end
       return o
     end
 
@@ -622,26 +625,20 @@ http {
 
       # deonionify the request_uri for forwarding (both path and args)
       set_by_lua_block $request_uri2 {
-        local old = ngx.var.request_uri or ""
-        -- onion_to_dns is potentially expensive at scale, so do a cheap test
-        local m, err = ngx.re.match(old, "(?:%LEFT_TLD_RE%)[a-z2-7]{16}(?:[a-z2-7]{40})?\\.onion\\b", "io")
-        if not m then -- nothing to attempt to rewrite, quick return
-          return old
-        end
-        return onion_to_dns(old)
+        return onion_to_dns(ngx.var.request_uri)
       }
 
       %%IF %DEONIONIFY_REQUESTS%
-      # deonionify_requests
+      # deonionify_requests (specifically, the body; path and args come as standard)
       access_by_lua_block {
+        if ngx.req.get_method() == "POST" then
           ngx.req.read_body()
-          local oldbody = ngx.req.get_body_data()
-          -- onion_to_dns is potentially expensive at scale, so do a cheap test
-          local m, err = ngx.re.match(oldbody, "(?:%LEFT_TLD_RE%)[a-z2-7]{16}(?:[a-z2-7]{40})?\\.onion\\b", "io")
-          if m then -- we may have work to do
-            local newbody = onion_to_dns(oldbody)
-            ngx.req.set_body_data(newbody)
+          local old = ngx.req.get_body_data()
+          local new = onion_to_dns(old)
+          if new != old -- hopefully fast, thank you lua
+            ngx.req.set_body_data(new)
           end
+        end
       }
       %%ELSE
       # no deonionify_requests