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DOCSP-46812 - Distribute Type Hints (mongodb#167)
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source/aggregation/aggregation-tutorials/filtered-subset.txt

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@@ -90,9 +90,7 @@ Tutorial
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Next, add a :manual:`$sort
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</reference/operator/aggregation/sort>` stage that sorts the
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documents in descending order by the ``dateofbirth`` field to
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list the youngest people first. Because Python dictionaries don't maintain the
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order of their elements, use a ``SON``or ``OrderedDict`` object
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instead:
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list the youngest people first:
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.. literalinclude:: /includes/aggregation/filtered-subset.py
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:language: python

source/connect/mongoclient.txt

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@@ -119,7 +119,7 @@ constructor accepts. All parameters are optional.
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:wikipedia:`round-robin DNS <Round-robin_DNS>` addresses.
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**Data type:** ``Union[str, Sequence[str]]``
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**Default value:** ``"localhost"``
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| **Default value:** ``"localhost"``
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* - ``port``
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- The port number {+mdb-server+} is running on.
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instead of using this parameter.
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**Data type:** ``int``
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**Default value:** ``27017``
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| **Default value:** ``27017``
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* - ``document_class``
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- The default class that the client uses to decode BSON documents returned by queries.
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This parameter supports the ``bson.raw_bson.RawBSONDocument`` type, as well as
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subclasses of the ``collections.abc.Mapping`` type, such as ``bson.son.SON``.
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This parameter accepts the following types:
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If you specify ``bson.son.SON`` as the document class, you must also specify types
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for the key and value.
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- ``bson.raw_bson.RawBSONDocument``. To learn more about the ``RawBSONDocument`` class,
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see :ref:`pymongo-bson-raw`.
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- A subclass of the ``collections.abc.Mapping`` type, such as ``OrderedDict``.
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Depending on the strictness of your type-checking rules, you might also need to
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specify types for the key and value, as shown in the following example:
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.. code-block:: python
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client = MongoClient(document_class=OrderedDict[str, int])
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- A subclass of the ``TypedDict`` type. To pass a ``TypedDict`` subclass for this
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parameter, you must also include the class in a type hint for your ``MongoClient``
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object, as shown in the following example:
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.. code-block:: python
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client: MongoClient[MyTypedDict] = MongoClient()
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.. include:: /includes/type-hints/typeddict-availability.rst
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**Data type:** ``Type[_DocumentType]``
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**Default:** ``dict``
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* - ``tz_aware``
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- If this parameter is ``True``, the client treats ``datetime`` values as aware.
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Do not copy an instance of the ``MongoClient`` class from the parent process to a child
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process.
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Type Hints
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.. _pymongo-type-hints-client:
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Type Hints
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----------
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If you're using Python v3.5 or later, you can add type hints to your Python code.
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.. include:: /includes/type-hints/intro.rst
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The following code example shows how to declare a type hint for a ``MongoClient``
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object:
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To use type hints in your {+driver-short+} application, you must add a type annotation to your
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``MongoClient`` object, as shown in the following example:
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.. code-block:: python
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client: MongoClient = MongoClient()
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In the previous example, the code doesn't specify a type for the documents that the
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``MongoClient`` object will work with. To specify a document type,
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include the ``Dict[str, Any]`` type when you
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create the ``MongoClient`` object, as shown in the following example:
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For more accurate type information, you can include the generic document type
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``Dict[str, Any]`` in your type annotation. This data type matches all documents in MongoDB.
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The following example shows how to include this data type in your type annotation:
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.. code-block:: python
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from typing import Any, Dict
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client: MongoClient[Dict[str, Any]] = MongoClient()
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If all the documents that you are working with correspond to a single custom type, you
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can specify the custom type as a type hint for your ``MongoClient`` object. This
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provides more accurate type information than the generic ``Dict[str, Any]`` type.
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The following example shows how to specify the ``Movie`` type as a type hint for a
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``MongoClient`` object:
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.. code-block:: python
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from typing import TypedDict
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class Movie(TypedDict):
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name: str
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year: int
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client: MongoClient[Movie] = MongoClient()
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Troubleshooting
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---------------
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multithreaded contexts with ``fork()``, see `Issue 6721 <http://bugs.python.org/issue6721>`__
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in the Python Issue Tracker.
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.. include:: /includes/type-hints/troubleshooting-client-type.rst
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.. include:: /includes/type-hints/troubleshooting-incompatible-type.rst
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API Documentation
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-----------------

source/data-formats/bson.txt

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{"address": {"street": "Pizza St", "zipcode": "10003"}, "coord": [-73.982419, 41.579505], "cuisine": "Pizza", "name": "Mongo's Pizza"}
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.. _pymongo-bson-raw:
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Work with Raw BSON Data
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-----------------------
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source/databases-collections.txt

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@@ -302,9 +302,79 @@ To learn more about supported retryable read operations, see :manual:`Retryable
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in the {+mdb-server+} manual. To learn more about supported retryable write
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operations, see :manual:`Retryable Writes </core/retryable-writes/>` in the {+mdb-server+} manual.
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.. _pymongo-databases-collection-type-hints:
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Type Hints
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----------
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.. include:: /includes/type-hints/intro.rst
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.. note:: TypedDict in Python 3.7 and Earlier
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.. include:: /includes/type-hints/typeddict-availability.rst
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Database
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~~~~~~~~
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If all documents in a database match a well-defined schema, you can specify a type hint
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that uses a Python class to represent the documents' structure. By including this class
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in the type hint for your ``Database`` object, you can ensure that all documents you
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store or retrieve have the required structure. This provides more accurate type
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checking and code completion than the default ``Dict[str, Any]`` type.
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First, define a class to represent a document from the database. The class must inherit
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from the ``TypedDict`` class and must contain the same fields as the documents in the
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database. After you define your class, include its name as the generic type for the
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``Database`` type hint.
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The following example defines a ``Movie`` class and uses it as the
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generic type for a ``Database`` type hint:
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.. code-block:: python
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:emphasize-lines: 5-7, 10
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from typing import TypedDict
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from pymongo import MongoClient
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from pymongo.database import Database
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class Movie(TypedDict):
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name: str
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year: int
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client: MongoClient = MongoClient()
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database: Database[Movie] = client["test_database"]
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Collection
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~~~~~~~~~~
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Adding a generic type to a ``Collection`` type hint is similar to adding a generic type
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to a ``Database`` type hint. First, define a class that inherits from the ``TypedDict`` class
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and represents the structure of the
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documents in the collection. Then, include the class name as the generic type for the
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``Collection`` type hint, as shown in the following example:
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.. code-block:: python
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:emphasize-lines: 5-7,11
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from typing import TypedDict
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from pymongo import MongoClient
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from pymongo.collection import Collection
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class Movie(TypedDict):
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name: str
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year: int
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client: MongoClient = MongoClient()
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database = client["test_database"]
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collection: Collection[Movie] = database["test_collection"]
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Troubleshooting
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---------------
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.. include:: /includes/type-hints/troubleshooting-client-type.rst
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.. include:: /includes/type-hints/troubleshooting-incompatible-type.rst
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.. include:: /includes/troubleshooting/read-write-options.rst
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API Documentation

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