Decouple rich binding support from the worker

Per discussion, the worker no longer includes support for rich bindings
by default.  The implementation have been moved to
azure-functions-python-library, and the runtime dependency on is has
been removed.

Author: elprans

azure/functions_worker/bindings/__init__.py

@@ -1,26 +1,14 @@
 from .context import Context
 from .meta import check_input_type_annotation
 from .meta import check_output_type_annotation
-from .meta import is_binding, is_trigger_binding
+from .meta import is_trigger_binding
 from .meta import from_incoming_proto, to_outgoing_proto
 from .out import Out
 
-# Import type implementations and converters
-# to get them registered and available:
-from . import blob  # NoQA
-from . import cosmosdb  # NoQA
-from . import eventgrid  # NoQA
-from . import eventhub  # NoQA
-from . import generic  # NoQA
-from . import http  # NoQA
-from . import queue  # NoQA
-from . import servicebus  # NoQA
-from . import timer  # NoQA
-
 
 __all__ = (
     'Out', 'Context',
-    'is_binding', 'is_trigger_binding',
+    'is_trigger_binding',
     'check_input_type_annotation', 'check_output_type_annotation',
     'from_incoming_proto', 'to_outgoing_proto',
 )

azure/functions_worker/bindings/blob.py

@@ -1,7 +1,4 @@
-from azure.functions import _abc as azf_abc
-
-
-class Context(azf_abc.Context):
+class Context:
 
     def __init__(self, func_name: str, func_dir: str,
                  invocation_id: str) -> None:

azure/functions_worker/bindings/context.py

@@ -0,0 +1,82 @@
+from .. import protos
+
+
+class Datum:
+    def __init__(self, value, type):
+        self.value = value
+        self.type = type
+
+    def __eq__(self, other):
+        if not isinstance(other, type(self)):
+            return False
+
+        return self.value == other.value and self.type == other.type
+
+    def __hash__(self):
+        return hash((type(self), (self.value, self.type)))
+
+    def __repr__(self):
+        val_repr = repr(self.value)
+        if len(val_repr) > 10:
+            val_repr = val_repr[:10] + '...'
+        return '<Datum {} {}>'.format(self.type, val_repr)
+
+    @classmethod
+    def from_typed_data(cls, td: protos.TypedData):
+        tt = td.WhichOneof('data')
+        if tt == 'http':
+            http = td.http
+            val = dict(
+                method=Datum(http.method, 'string'),
+                url=Datum(http.url, 'string'),
+                headers={
+                    k: Datum(v, 'string') for k, v in http.headers.items()
+                },
+                body=(
+                    Datum.from_typed_data(http.rawBody)
+                    or Datum(type='bytes', value=b'')
+                ),
+                params={
+                    k: Datum(v, 'string') for k, v in http.params.items()
+                },
+                query={
+                    k: Datum(v, 'string') for k, v in http.query.items()
+                },
+            )
+        elif tt == 'string':
+            val = td.string
+        elif tt == 'bytes':
+            val = td.bytes
+        elif tt == 'json':
+            val = td.json
+        elif tt is None:
+            return None
+        else:
+            raise NotImplementedError(
+                'unsupported TypeData kind: {!r}'.format(tt)
+            )
+
+        return cls(val, tt)
+
+
+def datum_as_proto(datum: Datum) -> protos.TypedData:
+    if datum.type == 'string':
+        return protos.TypedData(string=datum.value)
+    elif datum.type == 'bytes':
+        return protos.TypedData(bytes=datum.value)
+    elif datum.type == 'json':
+        return protos.TypedData(json=datum.value)
+    elif datum.type == 'http':
+        return protos.TypedData(http=protos.RpcHttp(
+            status_code=datum.value['status_code'].value,
+            headers={
+                k: v.value
+                for k, v in datum.value['headers'].items()
+            },
+            enable_content_negotiation=False,
+            body=datum_as_proto(datum.value['body']),
+        ))
+    else:
+        raise NotImplementedError(
+            'unexpected Datum type: {!r}'.format(datum.type)
+        )