implement #29

dataclass_rest/boundmethod.py

@@ -1,3 +1,5 @@
+import copy
+
 from abc import ABC, abstractmethod
 from inspect import getcallargs
 from logging import getLogger
@@ -30,7 +32,15 @@ def _apply_args(self, *args, **kwargs) -> Dict:
         )
 
     def _get_url(self, args) -> str:
-        return self.method_spec.url_template.format(**args)
+        args = copy.copy(args)
+
+        if not self.method_spec.url_template_func_pop_args:
+            return self.method_spec.url_template_func(**args)
+
+        for arg in self.method_spec.url_template_func_pop_args:
+            args.pop(arg)
+
+        return self.method_spec.url_template_func(**args)
 
     def _get_body(self, args) -> Any:
         python_body = args.get(self.method_spec.body_param_name)

dataclass_rest/methodspec.py

@@ -1,11 +1,13 @@
-from typing import Any, Dict, Type, Callable, List
+from typing import Any, Dict, Type, Callable, List, Optional
 
 
 class MethodSpec:
     def __init__(
             self,
             func: Callable,
-            url_template: str,
+            url_template: Optional[str],
+            url_template_func: Optional[Callable[..., str]],
+            url_template_func_pop_args: Optional[List[str]],
             http_method: str,
             response_type: Type,
             body_param_name: str,
@@ -17,6 +19,8 @@ def __init__(
     ):
         self.func = func
         self.url_template = url_template
+        self.url_template_func = url_template_func
+        self.url_template_func_pop_args = url_template_func_pop_args
         self.http_method = http_method
         self.response_type = response_type
         self.body_param_name = body_param_name

dataclass_rest/parse_func.py

@@ -1,16 +1,21 @@
 import string
 from inspect import getfullargspec, FullArgSpec, isclass
-from typing import Callable, List, Sequence, Any, Type, TypedDict, Dict
+from typing import Callable, List, Sequence, Any, Type, TypedDict, Dict, Union, Optional
 
 from .http_request import File
 from .methodspec import MethodSpec
 
 DEFAULT_BODY_PARAM = "body"
 
 
-def get_url_params(url_template: str) -> List[str]:
-    parsed_format = string.Formatter().parse(url_template)
-    return [x[1] for x in parsed_format]
+def get_url_params(url_template: Union[str, Callable[..., str]], arg_spec: Optional[FullArgSpec] = None) -> List[str]:
+    is_string = isinstance(url_template, str)
+
+    if is_string:
+        parsed_format = string.Formatter().parse(url_template)
+        return [x[1] for x in parsed_format]
+    else:
+        return arg_spec.args
 
 
 def create_query_params_type(
@@ -54,19 +59,42 @@ def get_file_params(spec):
 def parse_func(
         func: Callable,
         method: str,
-        url_template: str,
+        url_template: Union[str, Callable[..., str]],
         additional_params: Dict[str, Any],
         is_json_request: bool,
         body_param_name: str,
 ) -> MethodSpec:
     spec = getfullargspec(func)
-    url_params = get_url_params(url_template)
     file_params = get_file_params(spec)
+
+    is_string_url_template = isinstance(url_template, str)
+    url_template_func = url_template.format if is_string_url_template else url_template
+
+    try:
+        url_template_func_arg_spec = getfullargspec(url_template_func)
+
+        url_template_func_args = set(url_template_func_arg_spec.args)
+        diff_kwargs = set(spec.kwonlyargs).difference(url_template_func_args)
+        diff_args = set(spec.args).difference(url_template_func_args)
+
+        url_template_func_pop_args = diff_args.union(diff_kwargs)
+    except TypeError as _exc:
+        url_template_func_arg_spec = None
+        url_template_func_pop_args = None
+
+    if is_string_url_template:
+        url_params = get_url_params(url_template)
+    else:
+        url_params = get_url_params(url_template_func, url_template_func_arg_spec)
+
     skipped_params = url_params + file_params + [body_param_name]
+
     return MethodSpec(
         func=func,
         http_method=method,
-        url_template=url_template,
+        url_template=url_template if is_string_url_template else None,
+        url_template_func=url_template_func,
+        url_template_func_pop_args=url_template_func_pop_args,
         query_params_type=create_query_params_type(spec, func, skipped_params),
         body_type=create_body_type(spec, body_param_name),
         response_type=create_response_type(spec),

dataclass_rest/rest.py

@@ -1,13 +1,13 @@
 from functools import partial
-from typing import Any, Dict, Optional, Callable
+from typing import Any, Dict, Optional, Callable, Union
 
 from .boundmethod import BoundMethod
 from .method import Method
 from .parse_func import parse_func, DEFAULT_BODY_PARAM
 
 
 def rest(
-        url_template: str,
+        url_template: Union[str, Callable[..., str]],
         *,
         method: str,
         body_name: str = DEFAULT_BODY_PARAM,