add an alternative constructor from_anystr() in HttpRequestBody

docs/advanced/additional-requests.rst

@@ -47,7 +47,7 @@ a generic HTTP Request: :class:`~.HttpRequest`. Here's an example:
                 "Page": page_num,
                 "ProductID": product_id,
             }
-        ).encode("utf-8"),
+        ),
     )
 
     print(request.url)     # https://www.api.example.com/product-pagination/
@@ -73,9 +73,12 @@ There are a few things to take note here:
 
     * ``body`` is represented by the :class:`~.HttpRequestBody` class which is
       simply a subclass of the ``bytes`` class. Using the ``body`` param of
-      :class:`~.HttpRequest` needs to have an input argument in ``bytes``. In our
-      code example, we've converted it from ``str`` to ``bytes`` using the ``encode()``
-      string method.
+      :class:`~.HttpRequest` supports converting it from ``str`` to ``bytes``
+      using **utf-8** as the default encoding.
+
+        * Note that the :meth:`~.HttpRequestBody.from_anystr` alternative constructor
+          for :class:`~.HttpRequestBody` can also be used to support instantiation of
+          ``str`` to ``bytes`` using any type of encoding (`default is` **utf-8**).
 
 Most of the time though, what you'll be defining would be ``GET`` requests. Thus,
 it's perfectly fine to define them as:
@@ -211,7 +214,7 @@ Thus, additional requests inside the Page Object are typically needed for it:
                         "Page": 2,
                         "ProductID": item["product_id"],
                     }
-                ).encode("utf-8"),
+                ),
             )
             item["related_product_ids"].extend(self.parse_related_product_ids(response))
             return item
@@ -293,7 +296,7 @@ list of :class:`~.HttpRequest` to be executed in batch using the
                         "Page": page_num,
                         "ProductID": item["product_id"],
                     }
-                ).encode("utf-8"),
+                ),
             )
 
         @staticmethod

tests/test_requests.py

@@ -37,9 +37,9 @@ def test_http_request_body_bytes_api():
     assert b"ent" in http_body
 
 
-def test_http_request_body_str_api():
-    with pytest.raises(TypeError):
-        HttpRequestBody("string content")
+def test_http_request_body_from_anystr():
+    http_body = HttpRequestBody.from_anystr("originally string")
+    assert http_body == b"originally string"
 
 
 def test_http_request_bytes_body():
@@ -49,8 +49,8 @@ def test_http_request_bytes_body():
 
 
 def test_http_request_body_conversion_str():
-    with pytest.raises(TypeError):
-        HttpRequest("http://example.com", body="content")
+    request = HttpRequest("http://example.com", body="content")
+    assert request.body == b"content"
 
 
 def test_http_request_body_validation_None():

web_poet/requests.py

@@ -42,7 +42,17 @@ class RequestBackendError(Exception):
 class HttpRequestBody(bytes):
     """A container for holding the raw HTTP request body in bytes format."""
 
-    pass
+    @classmethod
+    def from_anystr(
+        cls: Type[T_body], value: AnyStr, encoding: str = "utf-8"
+    ) -> T_body:
+        """An alternative constructor to handle both ``str`` and ``bytes`` types
+        of input argument.
+        """
+
+        if isinstance(value, str):
+            return cls(value, encoding=encoding)
+        return cls(value)
 
 
 class HttpRequestHeaders(CIMultiDict):
@@ -93,7 +103,7 @@ class HttpRequest:
         factory=HttpRequestHeaders, converter=HttpRequestHeaders
     )
     body: HttpRequestBody = attrs.field(
-        factory=HttpRequestBody, converter=HttpRequestBody
+        factory=HttpRequestBody, converter=HttpRequestBody.from_anystr  # type: ignore
     )