refactor: add automatic camelCase mashumaro aliases for `snake_case…

…` attrs (#26)

This commit adds automatic mashumaro camel case aliases for all fields
in our models. This will make them more scalable and less error-prone.

.changes/unreleased/Under the Hood-20240628-164812.yaml

@@ -0,0 +1,3 @@
+kind: Under the Hood
+body: Changed how field aliases to make it easier to define new models
+time: 2024-06-28T16:48:12.280623+02:00

dbtsl/models/__init__.py

@@ -4,10 +4,13 @@
 generated code from our GraphQL schema.
 """
 
+from .base import BaseModel
 from .dimension import Dimension, DimensionType
 from .measure import AggregationType, Measure
 from .metric import Metric, MetricType
 
+BaseModel._apply_aliases()
+
 __all__ = [
     "Dimension",
     "DimensionType",

dbtsl/models/base.py

@@ -0,0 +1,32 @@
+from dataclasses import fields, is_dataclass
+from types import MappingProxyType
+
+from mashumaro import DataClassDictMixin, field_options
+from mashumaro.config import BaseConfig
+
+
+def snake_case_to_camel_case(s: str) -> str:
+    """Convert a snake_case_string into a camelCaseString."""
+    tokens = s.split("_")
+    return tokens[0] + "".join(t.title() for t in tokens[1:])
+
+
+class BaseModel(DataClassDictMixin):
+    """Base class for all serializable models.
+
+    Adds some functionality like automatically creating camelCase aliases.
+    """
+
+    class Config(BaseConfig):  # noqa: D106
+        lazy_compilation = True
+
+    @classmethod
+    def _apply_aliases(cls) -> None:
+        """Apply camelCase aliases to all subclasses."""
+        for subclass in cls.__subclasses__():
+            assert is_dataclass(subclass), "Subclass of BaseModel must be dataclass"
+
+            for field in fields(subclass):
+                camel_name = snake_case_to_camel_case(field.name)
+                if field.name != camel_name:
+                    field.metadata = MappingProxyType(field_options(alias=camel_name))

dbtsl/models/dimension.py

@@ -1,7 +1,7 @@
 from dataclasses import dataclass
 from enum import Enum
 
-from mashumaro import DataClassDictMixin
+from dbtsl.models.base import BaseModel
 
 
 class DimensionType(str, Enum):
@@ -12,7 +12,7 @@ class DimensionType(str, Enum):
 
 
 @dataclass(frozen=True)
-class Dimension(DataClassDictMixin):
+class Dimension(BaseModel):
     """A metric dimension."""
 
     name: str

dbtsl/models/measure.py

@@ -1,8 +1,8 @@
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from enum import Enum
 from typing import Optional
 
-from mashumaro import DataClassDictMixin, field_options
+from dbtsl.models.base import BaseModel
 
 
 class AggregationType(str, Enum):
@@ -20,10 +20,10 @@ class AggregationType(str, Enum):
 
 
 @dataclass(frozen=True)
-class Measure(DataClassDictMixin):
+class Measure(BaseModel):
     """A measure."""
 
     name: str
-    agg_time_dimension: Optional[str] = field(metadata=field_options(alias="aggTimeDimension"))
+    agg_time_dimension: Optional[str]
     agg: AggregationType
     expr: str

dbtsl/models/metric.py

@@ -1,10 +1,7 @@
 from dataclasses import dataclass
 from enum import Enum
 
-from mashumaro import DataClassDictMixin
-
-# TODO @serramatutu: replace this file with codegen from GraphQL API
-# See: https://strawberry.rocks/docs/codegen/query-codegen
+from dbtsl.models.base import BaseModel
 
 
 class MetricType(str, Enum):
@@ -28,7 +25,7 @@ def missing(cls, _: str) -> "MetricType":
 
 
 @dataclass(frozen=True)
-class Metric(DataClassDictMixin):
+class Metric(BaseModel):
     """A metric."""
 
     name: str

dbtsl/models/query.py

@@ -1,11 +1,12 @@
 import base64
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from enum import Enum
 from functools import cached_property
 from typing import NewType, Optional
 
 import pyarrow as pa
-from mashumaro import DataClassDictMixin, field_options
+
+from dbtsl.models.base import BaseModel
 
 QueryId = NewType("QueryId", str)
 
@@ -21,15 +22,15 @@ class QueryStatus(str, Enum):
 
 
 @dataclass(frozen=True)
-class QueryResult(DataClassDictMixin):
+class QueryResult(BaseModel):
     """A query result containing its status, SQL and error/results."""
 
-    query_id: QueryId = field(metadata=field_options(alias="queryId"))
+    query_id: QueryId
     status: QueryStatus
     sql: Optional[str]
     error: Optional[str]
-    total_pages: Optional[int] = field(metadata=field_options(alias="totalPages"))
-    arrow_result: Optional[str] = field(metadata=field_options(alias="arrowResult"))
+    total_pages: Optional[int]
+    arrow_result: Optional[str]
 
     @cached_property
     def result_table(self) -> pa.Table:

tests/test_models.py

@@ -0,0 +1,32 @@
+from dataclasses import dataclass
+
+from mashumaro.codecs.basic import decode
+
+from dbtsl.models.base import BaseModel
+from dbtsl.models.base import snake_case_to_camel_case as stc
+
+
+def test_snake_case_to_camel_case() -> None:
+    assert stc("hello") == "hello"
+    assert stc("hello_world") == "helloWorld"
+    assert stc("Hello_world") == "HelloWorld"
+    assert stc("hello world") == "hello world"
+    assert stc("helloWorld") == "helloWorld"
+
+
+def test_base_model_auto_alias() -> None:
+    @dataclass
+    class SubModel(BaseModel):
+        hello_world: str
+
+    BaseModel._apply_aliases()
+
+    data = {
+        "helloWorld": "asdf",
+    }
+
+    model = SubModel.from_dict(data)
+    assert model.hello_world == "asdf"
+
+    codec_model = decode(data, SubModel)
+    assert codec_model.hello_world == "asdf"