add draft codes

scripts/webfinger_allowlist.lua

@@ -0,0 +1,44 @@
+function webfingerCallback(cfg)
+    local args, err = ngx.req.get_uri_args()
+    if err == "truncated" then
+      return false, 'uri args too long'
+    end
+
+    local resource = args['resource']
+    if resource ~= nil then
+      for _, account in ipairs(cfg.accounts) do
+        if resource == account then
+          return true
+        end
+      end
+    end
+
+    return false
+end
+
+return {
+    name='WebfingerAllowlist',
+    author='luna@l4.pm',
+    title='Webfinger Allowlist',
+    description=[[
+    Prevent unecessary DB load by discarding requests to users that we know
+    won't exist.
+
+    Useful for small instances.
+    ]],
+    apiVersion=1,
+    callback=webfingerCallback,
+    callbacks = {
+        ['/.well-known/webfinger'] = webfingerCallback
+    },
+    config={
+        ['accounts'] = {
+            type='table',
+            value={
+                type='string',
+                description='ap id'
+            },
+            description = 'list of account ids (in email@domain form) to pass through to AP'
+        }
+    },
+}