New .add_memory_database() method, closes #1247

datasette/app.py

@@ -390,6 +390,9 @@ def add_database(self, db, name=None):
         self.databases[name] = db
         return db
 
+    def add_memory_database(self, memory_name):
+        return self.add_database(Database(self, memory_name=memory_name))
+
     def remove_database(self, name):
         self.databases.pop(name)
 

docs/internals.rst

@@ -273,7 +273,25 @@ The ``db`` parameter should be an instance of the ``datasette.database.Database`
 
 This will add a mutable database and serve it at ``/my-new-database``.
 
-To create a shared in-memory database named ``statistics``, use the following:
+``.add_database()`` returns the Database instance, with its name set as the ``database.name`` attribute. Any time you are working with a newly added database you should use the return value of ``.add_database()``, for example:
+
+.. code-block:: python
+
+    db = datasette.add_database(Database(datasette, memory_name="statistics"))
+    await db.execute_write("CREATE TABLE foo(id integer primary key)", block=True)
+
+.. _datasette_add_memory_database:
+
+.add_memory_database(name)
+--------------------------
+
+Adds a shared in-memory database with the specified name:
+
+.. code-block:: python
+
+    datasette.add_memory_database("statistics")
+
+This is a shortcut for the following:
 
 .. code-block:: python
 
@@ -284,14 +302,7 @@ To create a shared in-memory database named ``statistics``, use the following:
         memory_name="statistics"
     ))
 
-This database will be served at ``/statistics``.
-
-``.add_database()`` returns the Database instance, with its name set as the ``database.name`` attribute. Any time you are working with a newly added database you should use the return value of ``.add_database()``, for example:
-
-.. code-block:: python
-
-    db = datasette.add_database(Database(datasette, memory_name="statistics"))
-    await db.execute_write("CREATE TABLE foo(id integer primary key)", block=True)
+Using either of these pattern will result in the in-memory database being served at ``/statistics``.
 
 .. _datasette_remove_database:
 

tests/test_internals_database.py

@@ -479,9 +479,9 @@ async def test_attached_databases(app_client_two_attached_databases_crossdb_enab
 async def test_database_memory_name(app_client):
     ds = app_client.ds
     foo1 = ds.add_database(Database(ds, memory_name="foo"))
-    foo2 = ds.add_database(Database(ds, memory_name="foo"))
+    foo2 = ds.add_memory_database("foo")
     bar1 = ds.add_database(Database(ds, memory_name="bar"))
-    bar2 = ds.add_database(Database(ds, memory_name="bar"))
+    bar2 = ds.add_memory_database("bar")
     for db in (foo1, foo2, bar1, bar2):
         table_names = await db.table_names()
         assert table_names == []