[misc] support export ollama modelfile (#6899)

* support export ollama modelfile

* update config

* add system and num ctx

Former-commit-id: 8c2af7466f4015f300b51841db11bcd2505ebf20

src/llamafactory/data/template.py

@@ -239,11 +239,9 @@ class Template:
         Returns the jinja template.
         """
         prefix = self._convert_slots_to_jinja(self.format_prefix.apply(), tokenizer)
-        system_message = self._convert_slots_to_jinja(
-            self.format_system.apply(), tokenizer, placeholder="system_message"
-        )
-        user_message = self._convert_slots_to_jinja(self.format_user.apply(), tokenizer)
-        assistant_message = self._convert_slots_to_jinja(self.format_assistant.apply(), tokenizer)
+        system = self._convert_slots_to_jinja(self.format_system.apply(), tokenizer, placeholder="system_message")
+        user = self._convert_slots_to_jinja(self.format_user.apply(), tokenizer)
+        assistant = self._convert_slots_to_jinja(self.format_assistant.apply(), tokenizer)
         jinja_template = ""
         if prefix:
             jinja_template += "{{ " + prefix + " }}"
@@ -254,13 +252,13 @@ class Template:
         jinja_template += (
             "{% if messages[0]['role'] == 'system' %}{% set loop_messages = messages[1:] %}"
             "{% set system_message = messages[0]['content'] %}{% else %}{% set loop_messages = messages %}{% endif %}"
-            "{% if system_message is defined %}{{ " + system_message + " }}{% endif %}"
+            "{% if system_message is defined %}{{ " + system + " }}{% endif %}"
             "{% for message in loop_messages %}"
             "{% set content = message['content'] %}"
             "{% if message['role'] == 'user' %}"
-            "{{ " + user_message + " }}"
+            "{{ " + user + " }}"
             "{% elif message['role'] == 'assistant' %}"
-            "{{ " + assistant_message + " }}"
+            "{{ " + assistant + " }}"
             "{% endif %}"
             "{% endfor %}"
         )
@@ -276,6 +274,64 @@ class Template:
             except ValueError as e:
                 logger.info_rank0(f"Cannot add this chat template to tokenizer: {e}.")
 
+    @staticmethod
+    def _convert_slots_to_ollama(
+        slots: "SLOTS", tokenizer: "PreTrainedTokenizer", placeholder: str = "content"
+    ) -> str:
+        r"""
+        Converts slots to ollama template.
+        """
+        slot_items = []
+        for slot in slots:
+            if isinstance(slot, str):
+                slot_pieces = slot.split("{{content}}")
+                if slot_pieces[0]:
+                    slot_items.append(slot_pieces[0])
+                if len(slot_pieces) > 1:
+                    slot_items.append("{{ " + placeholder + " }}")
+                    if slot_pieces[1]:
+                        slot_items.append(slot_pieces[1])
+            elif isinstance(slot, set):  # do not use {{ eos_token }} since it may be replaced
+                if "bos_token" in slot and tokenizer.bos_token_id is not None:
+                    slot_items.append(tokenizer.bos_token)
+                elif "eos_token" in slot and tokenizer.eos_token_id is not None:
+                    slot_items.append(tokenizer.eos_token)
+            elif isinstance(slot, dict):
+                raise ValueError("Dict is not supported.")
+
+        return "".join(slot_items)
+
+    def _get_ollama_template(self, tokenizer: "PreTrainedTokenizer") -> str:
+        r"""
+        Returns the ollama template.
+        """
+        prefix = self._convert_slots_to_ollama(self.format_prefix.apply(), tokenizer)
+        system = self._convert_slots_to_ollama(self.format_system.apply(), tokenizer, placeholder=".System")
+        user = self._convert_slots_to_ollama(self.format_user.apply(), tokenizer, placeholder=".Content")
+        assistant = self._convert_slots_to_ollama(self.format_assistant.apply(), tokenizer, placeholder=".Content")
+        return (
+            f"{prefix}{{{{ if .System }}}}{system}{{{{ end }}}}"
+            f"""{{{{ range .Messages }}}}{{{{ if eq .Role "user" }}}}{user}"""
+            f"""{{{{ else if eq .Role "assistant" }}}}{assistant}{{{{ end }}}}{{{{ end }}}}"""
+        )
+
+    def get_ollama_modelfile(self, tokenizer: "PreTrainedTokenizer") -> str:
+        r"""
+        Returns the ollama modelfile.
+
+        TODO: support function calling.
+        """
+        modelfile = f'FROM .\n\nTEMPLATE """{self._get_ollama_template(tokenizer)}"""\n\n'
+
+        if self.default_system:
+            modelfile += f'SYSTEM system "{self.default_system}"\n\n'
+
+        for stop_token_id in self.get_stop_token_ids(tokenizer):
+            modelfile += f'PARAMETER stop "{tokenizer.convert_ids_to_tokens(stop_token_id)}"\n'
+
+        modelfile += "PARAMETER num_ctx 4096\n"
+        return modelfile
+
 
 @dataclass
 class Llama2Template(Template):
@@ -1020,7 +1076,7 @@ _register_template(
 )
 
 
-# copied from chatml template
+# copied from minicpm_v template
 _register_template(
     name="minicpm_o",
     format_user=StringFormatter(slots=["<|im_start|>user\n{{content}}<|im_end|>\n<|im_start|>assistant\n"]),