Add warning against subapi instantiation in docs (#4335)

Author: AbrilRBS

common/subapi_instantiation_warning.inc

@@ -0,0 +1,4 @@
+.. warning::
+
+    Subapis **must not** be initialized by themselves. They are intended to be
+    accessed only through the main :ref:`ConanAPI <reference_python_api_conan_api>` attributes.

reference/extensions/python_api.rst

@@ -35,6 +35,8 @@ and the rest of the members are considered private and can change without notice
    python_api/RemoveAPI
    python_api/UploadAPI
 
+.. include:: ../../common/subapi_instantiation_warning.inc
+
 There are also some model classes that represent the data structures used in the API.
 Note that as with the API, only the **documented** public members are guaranteed to be stable,
 and the rest of the members are considered private and can change without notice.

reference/extensions/python_api/CommandAPI.rst

@@ -3,6 +3,8 @@ Command API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.command
 
 .. autoclass:: CommandAPI

reference/extensions/python_api/ConfigAPI.rst

@@ -3,6 +3,8 @@ Config API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.config
 
 .. autoclass:: ConfigAPI

reference/extensions/python_api/DownloadAPI.rst

@@ -3,6 +3,8 @@ Download API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.download
 
 .. autoclass:: DownloadAPI

reference/extensions/python_api/ExportAPI.rst

@@ -3,6 +3,8 @@ Export API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.export
 
 .. autoclass:: ExportAPI

reference/extensions/python_api/GraphAPI.rst

@@ -3,6 +3,8 @@ Graph API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.graph
 
 .. autoclass:: GraphAPI

reference/extensions/python_api/InstallAPI.rst

@@ -3,6 +3,8 @@ Install API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.install
 
 .. autoclass:: InstallAPI

reference/extensions/python_api/ListAPI.rst

@@ -3,6 +3,8 @@ List API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.list
 
 .. autoclass:: ListAPI

reference/extensions/python_api/NewAPI.rst

@@ -3,6 +3,8 @@ New API
 
 .. include:: ../../../common/experimental_warning.inc
 
+.. include:: ../../../common/subapi_instantiation_warning.inc
+
 .. currentmodule:: conan.api.subapi.new
 
 .. autoclass:: NewAPI