add support for dataclass serialisation

noodles/draw_workflow/draw_workflow.py

@@ -19,16 +19,26 @@ def _format_arg_list(a, v):
 
     s = "({0}{1})"
     for i in a[:-1]:
+        if isinstance(i, float):
+            istr = "{:.6}".format(i)
+        else:
+            istr = str(i)
+
         s = s.format(
-            _sugar(str(i))
+            _sugar(istr)
             if i is not Parameter.empty
             else "\u2014", ", {0}{1}")
 
     if v:
         return s.format("\u2026", "")
 
+    if isinstance(a[-1], float):
+        istr = "{:.6}".format(a[-1])
+    else:
+        istr = str(a[-1])
+
     return s.format(
-        _sugar(str(a[-1]))
+        _sugar(istr)
         if a[-1] is not Parameter.empty
         else "\u2014", "")
 

noodles/serial/__init__.py

@@ -1,10 +1,15 @@
-# from .numpy import registry as numpy
+try:
+    from .numpy import registry as numpy
+except ImportError:
+    numpy = None
+
 from .pickle import registry as pickle
 from .base import registry as base
 from .as_dict import AsDict
 from .namedtuple import registry as namedtuple
 from .registry import (Registry, Serialiser, RefObject)
 from .reasonable import (Reasonable)
 from .path import SerPath
+
 __all__ = ['pickle', 'base', 'Registry', 'Serialiser', 'SerPath',
-           'RefObject', 'AsDict', 'namedtuple', 'Reasonable']
+           'RefObject', 'AsDict', 'namedtuple', 'Reasonable', 'numpy']

noodles/serial/base.py

@@ -3,6 +3,15 @@
 from pathlib import Path
 import base64
 
+try:
+    import dataclasses
+    from .dataclass import SerDataClass
+except ImportError:
+    use_dataclasses = False
+    SerDataClass = None
+else:
+    use_dataclasses = True
+
 from ..interface import (Fail, PromisedObject, Quote)
 from ..lib import (object_name, look_up, importable, unwrap, is_unwrapped)
 from ..workflow import (Workflow, NodeData, FunctionNode, ArgumentAddress,
@@ -208,6 +217,10 @@ def _noodles_hook(obj):
     if '__member_of__' in dir(obj) and obj.__member_of__:
         return '<method>'
 
+    if use_dataclasses and \
+            dataclasses.is_dataclass(obj) and not isinstance(obj, type):
+        return '<dataclass>'
+
     if importable(obj):
         return '<importable>'
 
@@ -259,7 +272,8 @@ def registry():
             '<boundmethod>': SerBoundMethod(),
             '<importable>': SerImportable(),
             '<automagic>': SerAuto(),
-            '<unwrapped>': SerUnwrapped()
+            '<unwrapped>': SerUnwrapped(),
+            '<dataclass>': SerDataClass()
         },
         hook_fn=_noodles_hook,
         default=SerUnknown(),

noodles/serial/dataclass.py

@@ -0,0 +1,13 @@
+import dataclasses
+from .registry import Serialiser
+
+
+class SerDataClass(Serialiser):
+    def __init__(self):
+        super(SerDataClass, self).__init__('<dataclass>')
+
+    def encode(self, obj, make_rec):
+        return make_rec(obj.__dict__)
+
+    def decode(self, cls, data):
+        return cls(**data)