feat(ai-prompt-guard): increase the maximum length of regex expression

to 500 for both allow and deny parameter

FTI-5767

changelog/unreleased/kong/feat-increase-ai-anthropic-regex-expression-length.yml

@@ -0,0 +1,4 @@
+message: |
+  **AI-Prompt-Guard**: increase the maximum length of regex expression for both allow and deny parameter
+scope: Plugin
+type: feature

kong/plugins/ai-prompt-guard/schema.lua

@@ -15,7 +15,7 @@ return {
               elements = {
                 type = "string",
                 len_min = 1,
-                len_max = 50,
+                len_max = 500,
               }}},
           { deny_patterns = {
               description = "Array of invalid patterns, or invalid questions from the 'user' role in chat.",
@@ -25,7 +25,7 @@ return {
               elements = {
                 type = "string",
                 len_min = 1,
-                len_max = 50,
+                len_max = 500,
               }}},
           { allow_all_conversation_history = {
               description = "If true, will ignore all previous chat prompts from the conversation history.",

spec/03-plugins/42-ai-prompt-guard/00_config_spec.lua

@@ -42,15 +42,15 @@ describe(PLUGIN_NAME .. ": (schema)", function()
     local config = {
       allow_all_conversation_history = true,
       allow_patterns = {
-        [1] = "123456789012345678901234567890123456789012345678901" -- 51
+        [1] = string.rep('x', 501)
       },
     }
 
     local ok, err = validate(config)
 
     assert.is_falsy(ok)
     assert.not_nil(err)
-    assert.same({ config = {allow_patterns = { [1] = "length must be at most 50" }}}, err)
+    assert.same({ config = {allow_patterns = { [1] = "length must be at most 500" }}}, err)
   end)
 
   it("won't allow too many array items", function()