def test_parse_csv(input_value, kwargs, expected_result, error):
if not error:
if kwargs:
result = parse_csv(input_value, **kwargs)
else:
result = parse_csv(input_value)
print(result)
assert isinstance(result, dict)
assert checkers.are_dicts_equivalent(result, expected_result)
else:
with pytest.raises(error):
if kwargs:
result = parse_csv(input_value, **kwargs)
else:
result = parse_csv(input_value)
def from_csv(cls,
serialized,
tablename,
metadata,
primary_key,
column_kwargs=None,
skip_nested=True,
default_to_str=False,
type_mapping=None,
delimiter='|',
wrap_all_strings=False,
null_text='None',
wrapper_character="'",
double_wrapper_character_when_nested=False,
escape_character="\\",
line_terminator='\r\n',
**kwargs):
"""Generate a :class:`Table` object from a
:term:`CSV <Comma-Separated Value (CSV)>` string.
.. versionadded: 0.3.0
:param serialized: The CSV data whose column headers will be treated as column
names, while value data types will determine :term:`model attribute` data
types.
.. note::
If a Path-like object, will read the file contents from a file that is assumed
to include a header row. If a :class:`str <python:str>` and has more than
one record (line), will assume the first line is a header row. If a
:class:`list <python:list>`, will assume the first item is the header row.
:type serialized: :class:`str <python:str>` / Path-like object /
:class:`list <python:list>`
:param tablename: The name of the SQL table to which the model corresponds.
:type tablename: :class:`str <python:str>`
:param metadata: a :class:`MetaData <sqlalchemy:sqlalchemy.schema.MetaData>`
object which will contain this table. The metadata is used as a point of
association of this table with other tables which are referenced via foreign
key. It also may be used to associate this table with a particular
:class:`Connectable <sqlalchemy:sqlalchemy.engine.Connectable>`.
:type metadata: :class:`MetaData <sqlalchemy:sqlalchemy.schema.MetaData>`
:param primary_key: The name of the column/key that should be used as the table's
primary key.
:type primary_key: :class:`str <python:str>`
:param column_kwargs: An optional dictionary whose keys correspond to
column/key, and whose values are themselves dictionaries with keyword
arguments that will be passed ot the applicable :class:`Column`
constructor. Defaults to :obj:`None <python:None>`.
:type column_kwargs: :class:`dict <python:dict>` / :obj:`None <python:None>`
:param skip_nested: If ``True`` then any keys in ``serialized`` that
feature nested items (e.g. iterables, :class:`dict <python:dict>` objects,
etc.) will be ignored. If ``False``, will treat nested items as
:class:`str <python:str>`. Defaults to ``True``.
:type skip_nested: :class:`bool <python:bool>`
:param default_to_str: If ``True``, will automatically set a key/column whose
value type cannot be determined to ``str``
(:class:`Text <sqlalchemy:sqlalchemy.types.Text>`). If ``False``, will
use the value type's ``__name__`` attribute and attempt to find a mapping.
Defaults to ``False``.
:type default_to_str: :class:`bool <python:bool>`
:param type_mapping: Determines how value types in ``serialized`` map to
SQL column data types. To add a new mapping or override a default, set a
key to the name of the value type in Python, and set the value to a
:doc:`SQLAlchemy Data Type <sqlalchemy:core/types>`. The following are the
default mappings applied:
.. list-table::
:widths: 30 30
:header-rows: 1
* - Python Literal
- SQL Column Type
* - ``bool``
- :class:`Boolean <sqlalchemy:sqlalchemy.types.Boolean>`
* - ``str``
- :class:`Text <sqlalchemy:sqlalchemy.types.Text>`
* - ``int``
- :class:`Integer <sqlalchemy:sqlalchemy.types.Integer>`
* - ``float``
- :class:`Float <sqlalchemy:sqlalchemy.types.Float>`
* - ``date``
- :class:`Date <sqlalchemy:sqlalchemy.types.Date>`
* - ``datetime``
- :class:`DateTime <sqlalchemy:sqlalchemy.types.DateTime>`
* - ``time``
- :class:`Time <sqlalchemy:sqlalchemy.types.Time>`
:type type_mapping: :class:`dict <python:dict>` with type names as keys and
column data types as values.
:param delimiter: The delimiter used between columns. Defaults to ``|``.
:type delimiter: :class:`str <python:str>`
:param wrapper_character: The string used to wrap string values when
wrapping is applied. Defaults to ``'``.
:type wrapper_character: :class:`str <python:str>`
:param null_text: The string used to indicate an empty value if empty
values are wrapped. Defaults to `None`.
:type null_text: :class:`str <python:str>`
:param kwargs: Any additional keyword arguments will be passed to the
:class:`Table` constructor. For a full list of options, please see
:class:`sqlalchemy.schema.Table <sqlalchemy:sqlalchemy.schema.Table>`.
:returns: A :class:`Table` object.
:rtype: :class:`Table`
:raises DeserializationError: if ``serialized`` is not a valid
:class:`str <python:str>`
:raises UnsupportedValueTypeError: when a value in ``serialized`` does not
have a corresponding key in ``type_mapping``
:raises ValueError: if ``tablename`` is empty
:raises ValueError: if ``primary_key`` is empty
:raises CSVStructureError: if there are less than 2 (two) rows in ``serialized``
or if column headers are not valid Python variable names
"""
# pylint: disable=line-too-long,invalid-name,too-many-arguments
if not checkers.is_file(serialized):
serialized = read_csv_data(serialized, single_record=False)
from_csv = parse_csv(serialized,
delimiter=delimiter,
wrap_all_strings=wrap_all_strings,
null_text=null_text,
wrapper_character=wrapper_character,
double_wrapper_character_when_nested=
double_wrapper_character_when_nested,
escape_character=escape_character,
line_terminator=line_terminator)
table = cls.from_dict(from_csv,
tablename,
metadata,
primary_key,
column_kwargs=column_kwargs,
skip_nested=skip_nested,
default_to_str=default_to_str,
type_mapping=type_mapping,
**kwargs)
return table
def generate_model_from_csv(serialized,
tablename,
primary_key,
cls = BaseModel,
serialization_config = None,
skip_nested = True,
default_to_str = False,
type_mapping = None,
base_model_attrs = None,
delimiter = '|',
wrap_all_strings = False,
null_text = 'None',
wrapper_character = "'",
double_wrapper_character_when_nested = False,
escape_character = "\\",
line_terminator = '\r\n',
**kwargs):
"""Generate a :term:`model class` from a serialized
:term:`CSV <Comma-Separated Value (CSV)>` string.
.. versionadded: 0.3.0
.. note::
This function *cannot* programmatically create
:term:`relationships <relationship>`, :term:`hybrid properties <hybrid property>`,
or :term:`association proxies <association proxy>`.
:param serialized: The CSV data whose column headers will be treated as column
names, while value data types will determine :term:`model attribute` data
types.
.. note::
If a Path-like object, will read the file contents from a file that is assumed
to include a header row. If a :class:`str <python:str>` and has more than
one record (line), will assume the first line is a header row. If a
:class:`list <python:list>`, will assume the first item is the header row.
:type serialized: :class:`str <python:str>` / Path-like object /
:class:`list <python:list>`
:param tablename: The name of the SQL table to which the model corresponds.
:type tablename: :class:`str <python:str>`
:param primary_key: The name of the column/key that should be used as the table's
primary key.
:type primary_key: :class:`str <python:str>`
:param cls: The base class to use when generating a new :term:`model class`.
Defaults to :class:`BaseModel` to provide serialization/de-serialization
support.
If a :class:`tuple <python:tuple>` of classes, will include :class:`BaseModel`
in that list of classes to mixin serialization/de-serialization support.
If not :obj:`None <python:None>` and not a :class:`tuple <python:tuple>`, will mixin
:class:`BaseModel` with the value passed to provide
serialization/de-serialization support.
:type cls: :obj:`None <python:None>` / :class:`tuple <python:tuple>` of
classes / class object
:param serialization_config: Collection of
:class:`AttributeConfiguration <sqlathanor.attributes.AttributeConfiguration>`
that determine the generated model's
:term:`serialization`/:term:`de-serialization`
:ref:`configuration <configuration>`. If :obj:`None <python:None>`, will
support serialization and de-serialization across all keys in
``serialized_dict``. Defaults to :obj:`None <python:None>`.
:type serialization_config: Iterable of
:class:`AttributeConfiguration <sqlathanor.attributes.AttributeConfiguration>`
or coercable :class:`dict <python:dict>` objects / :obj:`None <python:None>`
:param skip_nested: If ``True`` then any keys in ``serialized_json`` that
feature nested items (e.g. iterables, JSON objects, etc.) will be ignored.
If ``False``, will treat serialized items as :class:`str <python:str>`.
Defaults to ``True``.
:type skip_nested: :class:`bool <python:bool>`
:param default_to_str: If ``True``, will automatically set a key/column whose
value type cannot be determined to ``str``
(:class:`Text <sqlalchemy:sqlalchemy.types.Text>`). If ``False``, will
use the value type's ``__name__`` attribute and attempt to find a mapping.
Defaults to ``False``.
:type default_to_str: :class:`bool <python:bool>`
:param type_mapping: Determines how value types in ``serialized`` map to
SQL column data types. To add a new mapping or override a default, set a
key to the name of the value type in Python, and set the value to a
:doc:`SQLAlchemy Data Type <sqlalchemy:core/types>`. The following are the
default mappings applied:
.. list-table::
:widths: 30 30
:header-rows: 1
* - Python Literal
- SQL Column Type
* - ``bool``
- :class:`Boolean <sqlalchemy:sqlalchemy.types.Boolean>`
* - ``str``
- :class:`Text <sqlalchemy:sqlalchemy.types.Text>`
* - ``int``
- :class:`Integer <sqlalchemy:sqlalchemy.types.Integer>`
* - ``float``
- :class:`Float <sqlalchemy:sqlalchemy.types.Float>`
* - ``date``
- :class:`Date <sqlalchemy:sqlalchemy.types.Date>`
* - ``datetime``
- :class:`DateTime <sqlalchemy:sqlalchemy.types.DateTime>`
* - ``time``
- :class:`Time <sqlalchemy:sqlalchemy.types.Time>`
:type type_mapping: :class:`dict <python:dict>` with type names as keys and
column data types as values.
:param base_model_attrs: Optional :class:`dict <python:dict>` of special
attributes that will be applied to the generated
:class:`BaseModel <sqlathanor.declarative.BaseModel>` (e.g.
``__table_args__``). Keys will correspond to the attribute name, while the
value is the value that will be applied. Defaults to :obj:`None <python:None>`.
:type base_model_attrs: :class:`dict <python:dict>` / :obj:`None <python:None>`
:param delimiter: The delimiter used between columns. Defaults to ``|``.
:type delimiter: :class:`str <python:str>`
:param wrapper_character: The string used to wrap string values when
wrapping is applied. Defaults to ``'``.
:type wrapper_character: :class:`str <python:str>`
:param null_text: The string used to indicate an empty value if empty
values are wrapped. Defaults to `None`.
:type null_text: :class:`str <python:str>`
:param kwargs: Any additional keyword arguments will be passed to
:func:`declarative_base() <sqlathanor.declarative.declarative_base>` when
generating the programmatic :class:`BaseModel <sqlathanor.declarative.BaseModel>`.
:returns: :term:`Model class` whose structure matches ``serialized``.
:rtype: :class:`BaseModel`
:raises UnsupportedValueTypeError: when a value in ``serialized`` does not
have a corresponding key in ``type_mapping``
:raises ValueError: if ``tablename`` is empty
:raises DeserializationError: if ``serialized`` is not a valid
:class:`str <python:str>`
:raises CSVStructureError: if there are less than 2 (two) rows in ``serialized``
or if column headers are not valid Python variable names
"""
# pylint: disable=line-too-long,too-many-arguments
if not checkers.is_file(serialized):
serialized = read_csv_data(serialized, single_record = False)
from_csv = parse_csv(serialized,
delimiter = delimiter,
wrap_all_strings = wrap_all_strings,
null_text = null_text,
wrapper_character = wrapper_character,
double_wrapper_character_when_nested = double_wrapper_character_when_nested,
escape_character = escape_character,
line_terminator = line_terminator)
generated_model = generate_model_from_dict(from_csv,
tablename,
primary_key,
cls = cls,
serialization_config = serialization_config,
skip_nested = skip_nested,
default_to_str = default_to_str,
type_mapping = type_mapping,
base_model_attrs = base_model_attrs,
**kwargs)
return generated_model