.. Pipeline Import documentation

Import steps
============

.. module:: xmm.pipeline.steps

Steps required to import data from various sources in different formats.

ReadStep
~~~~~~~~

.. autoclass:: ReadStep

.. seealso:: :ref:`readers`

**Arguments:**

- `str` `load_class`: A Reader class or class name, see :ref:`readers`.
- dict `options`: Options to be passed down to the reader class.

**Added context:**

- str `mode`: Will be set to ``'import'``
- dict `read`
   - type `reader`: Will be set to the reader class.
   - dict `options`: The options supplied to the reader class.

ImportStep
~~~~~~~~~~

.. autoclass:: ImportStep

.. seealso:: :ref:`loaders`

**Arguments:**

- `str` `load_class`: A Loader class or class name, see :ref:`loaders`.
- `dict` `options`: Options to be passed down to the loader class.

**Added context:**

None.

ValueMapStep
~~~~~~~~~~~~

.. autoclass:: ValueMapStep
   :members: __init__

**Added context:**

None.

DbWriteStep
~~~~~~~~~~~

.. autoclass:: DbWriteStep
   :members: __init__

**Arguments:**

- `str` `id_field`: Will be removed from the import dataset and used as primary key to update existing instances.
- `str` `model`: Model name or class to save datasets as.
- `str`|`list` `primary_keys`: List of primary keys to use instead of a proper object ID.

**Added context:**

- `dict` `write`:
   - `type` `model`: Will be the model class used

RawDbWriteStep
~~~~~~~~~~~~~~

.. autoclass:: RawDbWriteStep
   :members: __init__

**Arguments:**

- `str` `collection_name`: Collection to import documents into.
- `str`|`list` `primary_keys`: When not empty, upsert are performed using values from these keys in each document.

**Added context:**

- `dict` `write`:
   - `type` `collection`: Equal to the ``collection_name`` option that was used.

DbDeleteStep
~~~~~~~~~~~~

.. autoclass:: DbDeleteStep
   :members: __init__

**Arguments:**

- `str` `model`: Model name or class to save datasets as.
- `str`|`list` `primary_keys`: List of keys to build the query.

**Added context:**

- `dict` `delete`:
   - `type` `model`: Will be the model class used

RawDbDeleteStep
~~~~~~~~~~~~~~~

.. autoclass:: RawDbDeleteStep
   :members: __init__

**Arguments:**

- `str` `collection_name`: Collection to delete documents from.
- `str`|`list` `primary_keys`: Set the query fields to select the documents to delete.

**Added context:**

- `dict` `delete`:
   - `type` `collection`: Equal to the ``collection_name`` option that was used.