From a0022981c7ca41eabc333d7b241b63af6835a469 Mon Sep 17 00:00:00 2001
From: ParthSareen <parth.sareen@ollama.com>
Date: Wed, 2 Apr 2025 16:58:22 -0700
Subject: [PATCH] server: improving grammar for JSON

---
 llm/server.go | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/llm/server.go b/llm/server.go
index e6046db60..1568d5f8a 100644
--- a/llm/server.go
+++ b/llm/server.go
@@ -636,13 +636,13 @@ func (s *llmServer) WaitUntilRunning(ctx context.Context) error {
 }
 
 var grammarJSON = `
-root   ::= object
-value  ::= object | array | string | number | ("true" | "false" | "null") ws
+root   ::= s object
+value  ::= ws (object | array | string | number | ("true" | "false" | "null")) ws
 object ::=
   "{" ws (
             string ":" ws value
     ("," ws string ":" ws value)*
-  )? "}" ws
+  )? "}" 
 array  ::=
   "[" ws (
             value
@@ -651,12 +651,12 @@ array  ::=
 string ::=
   "\"" (
     [^"\\\x7F\x00-\x1F] |
-    "\\" (["\\/bfnrt] | "u" [0-9a-fA-F] [0-9a-fA-F] [0-9a-fA-F] [0-9a-fA-F]) # escapes
-  )* "\"" ws
-number ::= ("-"? ([0-9] | [1-9] [0-9]*)) ("." [0-9]+)? ([eE] [-+]? [0-9]+)? ws
-# Optional space: by convention, applied in this grammar after literal chars when allowed
-ws ::= ([ \t\n] ws)?
-`
+    "\\" (["\\/bfnrt] | "u" [0-9a-fA-F] [0-9a-fA-F] [0-9a-fA-F] [0-9a-fA-F])
+  )* "\""
+number ::= "-"? ("0" | [1-9] [0-9]*) ("." [0-9]+)? ([eE] [-+]? [0-9]+)?
+ws     ::= [ \t \n \r]*
+s      ::= [ \n \t]
+t      ::= [ \t \r]*`
 
 const maxBufferSize = 512 * format.KiloByte
 
@@ -694,6 +694,8 @@ func (s *llmServer) Completion(ctx context.Context, req CompletionRequest, fn fu
 			break
 		case `"json"`:
 			req.Grammar = grammarJSON
+			slog.Info("using JSON grammar")
+			slog.Info(req.Grammar)
 		default:
 			if req.Format[0] != '{' {
 				return fmt.Errorf("invalid format: %q; expected \"json\" or a valid JSON Schema object", req.Format)