benchmark for cattrs (#513)

* benchmark for attr

* update HISTORY.rst

* * added benchmark using cattr
* add env "ATTRS=1" to benchmark runner to only compare again the two
  and save results in separate csv
* added section to docs/index

* nits

* re-run benchmark with cython pydantic; merge results back to main benchmarks results table

* pin pydantic to top of benchmark report

* remove attrs, fix cattrs

* update benchmarks output

* add change

benchmarks/requirements.txt

@@ -4,3 +4,5 @@ django               # pyup: ignore
 djangorestframework  # pyup: ignore
 #marshmallow          # pyup: ignore
 toastedmarshmallow   # pyup: ignore
+attr                 # pyup: ignore
+cattrs               # pyup: ignore

benchmarks/run.py

@@ -33,6 +33,11 @@ try:
 except Exception:
     TestToastedMarshmallow = None
 
+try:
+    from test_cattr import TestCAttr
+except Exception:
+    TestCAttr = None
+
 PUNCTUATION = ' \t\n!"#$%&\'()*+,-./'
 LETTERS = string.ascii_letters
 UNICODE = '\xa0\xad¡¢£¤¥¦§¨©ª«¬ ®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ'
@@ -42,7 +47,7 @@ random = random.SystemRandom()
 # in order of performance for csv
 other_tests = [
     t for t in
-    [TestToastedMarshmallow, TestMarshmallow, TestTrafaret, TestDRF]
+    [TestCAttr, TestToastedMarshmallow, TestMarshmallow, TestTrafaret, TestDRF]
     if t is not None
 ]
 

benchmarks/test_cattr.py

@@ -0,0 +1,101 @@
+from datetime import datetime
+from typing import List, Optional
+
+import attr
+import cattr
+from dateutil.parser import parse
+
+
+class TestCAttr:
+    package = 'cattr'
+    version = attr.__version__
+
+    def __init__(self, allow_extra):
+        # cf. https://github.com/Tinche/cattrs/issues/26 why at least structure_str is needed
+        def structure_str(s, _):
+            if not isinstance(s, str):
+                raise ValueError()
+            return s
+
+        def structure_int(i, _):
+            if not isinstance(i, int):
+                raise ValueError()
+            return i
+
+        class PositiveInt(int):
+            ...
+
+        def structure_posint(i, x):
+            i = PositiveInt(i)
+            if not isinstance(i, PositiveInt):
+                raise ValueError()
+            if i <= 0:
+                raise ValueError()
+            return i
+
+        cattr.register_structure_hook(datetime, lambda isostring, _: parse(isostring))
+        cattr.register_structure_hook(str, structure_str)
+        cattr.register_structure_hook(int, structure_int)
+        cattr.register_structure_hook(PositiveInt, structure_posint)
+
+        def str_len_val(max_len: int, min_len: int = 0, required: bool = False):
+            # validate the max len of a string and optionally its min len and whether None is
+            # an acceptable value
+            def _check_str_len(self, attribute, value):
+                if value is None:
+                    if required:
+                        raise ValueError("")
+                    else:
+                        return
+                if len(value) > max_len:
+                    raise ValueError("")
+                if min_len and len(value) < min_len:
+                    raise ValueError("")
+
+            return _check_str_len
+
+        def pos_int(self, attribute, value):
+            # Validate that value is a positive >0 integer; None is allowed
+            if value is None:
+                return
+            if value <= 0:
+                raise ValueError("")
+
+        @attr.s(auto_attribs=True, frozen=True, kw_only=True)
+        class Skill:
+            subject: str
+            subject_id: int
+            category: str
+            qual_level: str
+            qual_level_id: int
+            qual_level_ranking: float = 0
+
+        @attr.s(auto_attribs=True, frozen=True, kw_only=True)
+        class Location:
+            latitude: float = None
+            longitude: float = None
+
+        @attr.s(auto_attribs=True, frozen=True, kw_only=True)
+        class Model:
+            id: int
+            sort_index: float
+            client_name: str = attr.ib(validator=str_len_val(255))
+            # client_email: EmailStr = None
+            client_phone: Optional[str] = attr.ib(default=None, validator=str_len_val(255))
+            location: Optional[Location] = None
+
+            contractor: Optional[PositiveInt]
+            upstream_http_referrer: Optional[str] = attr.ib(default=None, validator=str_len_val(1023))
+            grecaptcha_response: str = attr.ib(validator=str_len_val(1000, 20, required=True))
+            last_updated: Optional[datetime] = None
+            skills: List[Skill] = []
+
+        self.model = Model
+
+    def validate(self, data):
+        try:
+            return True, cattr.structure(data, self.model)
+        except ValueError as e:
+            return False, str(e)
+        except TypeError as e:
+            return False, str(e)

changes/513-sebastianmika.md

@@ -0,0 +1 @@
+Add benchmarks for `cattrs`

docs/.benchmarks_table.md

@@ -2,8 +2,9 @@
 
 Package | Version | Relative Performance | Mean validation time
 --- | --- | --- | ---
-pydantic | `1.0b1` |  | 46.5μs
-marshmallow | `2.15.1` | 2.9x slower | 136.1μs
-trafaret | `1.2.0` | 3.3x slower | 154.2μs
-toasted-marshmallow | `2.15.2post1` | 3.4x slower | 159.4μs
-django-restful-framework | `3.10.3` | 12.4x slower | 577.0μs
+pydantic | `1.1` |  | 46.1μs
+cattr | `19.3.0` | 1.3x slower | 62.1μs
+marshmallow | `2.15.1` | 2.9x slower | 132.7μs
+toasted-marshmallow | `2.15.2post1` | 2.9x slower | 134.1μs
+trafaret | `2.0.0` | 3.3x slower | 153.5μs
+django-restful-framework | `3.10.3` | 12.7x slower | 586.1μs