fixup! doc: do not document user.meta-data key

doc/rtd/explanation/instancedata.rst

@@ -13,11 +13,9 @@ Instance metadata
 What is ``instance-data?``
 ==========================
 
-Each cloud provider presents unique configuration metadata to a launched cloud
-instance. ``Cloud-init`` crawls this metadata and then caches and exposes this
-information as a standardised and versioned JSON object known as
-``instance-data``. This ``instance-data`` may then be queried or later used
-by ``cloud-init`` in templated configuration and scripts.
+``instance-data`` is a JSON object which contains instance-specific variables
+in a standardized format. These variables may be used in ``cloud-init``
+templated cloud-init configurations.
 
 An example of a small subset of instance-data on a launched EC2 instance:
 
@@ -42,10 +40,9 @@ An example of a small subset of instance-data on a launched EC2 instance:
 Discovery
 =========
 
-One way to easily explore which ``instance-data`` variables are available on
-your machine is to use the :ref:`cloud-init query<cli_query>` tool.
-Warnings or exceptions will be raised on invalid ``instance-data`` keys,
-paths or invalid syntax.
+``instance-data`` can be inspected on a launched instance using
+:ref:`cloud-init query<cli_query>`. Warnings or exceptions will be raised
+on invalid ``instance-data`` keys, paths, or invalid syntax.
 
 The :command:`query` command also publishes ``userdata`` and ``vendordata``
 keys to the root user which will contain the decoded user and vendor data

doc/rtd/reference/datasources/lxd.rst

@@ -37,14 +37,27 @@ launched container, use either LXD profiles or
 one of the following keys:
 
 - ``cloud-init.vendor-data``: YAML which overrides any metadata values.
-- ``cloud-init.network-config``: YAML representing either :ref:`network_config_v1` or
-  :ref:`network_config_v2` format.
-- ``cloud-init.user-data``: YAML which takes precedence and overrides both metadata
-  and vendor data values.
-- ``user.any-key``: Custom user configuration key and value pairs, which can be
-  passed to ``cloud-init``. Those keys/values will be present in instance-data
-  which can be used by both `#template: jinja` #cloud-config templates and
-  the :command:`cloud-init query` command.
+- ``cloud-init.network-config``: YAML representing either
+  :ref:`network_config_v1` or :ref:`network_config_v2` format.
+- ``cloud-init.user-data``: YAML which takes precedence and overrides both
+  metadata and vendor data values.
+- ``user.<any-key>``: Keys prefixed with ``user.`` are included in
+  :ref:`instance data<instance_metadata>`. under ``ds.config.user.``. These
+  key-value pairs are used in :ref:`jinja templates<user_data_formats-jinja>`
+  and may be inspected on a launched instance using
+  ``cloud-init query ds.config``.
+
+.. note::
+
+    Periods (.) and hyphens (-) in Jinja2 have special meaning. Keys which contain a
+    period or hyphen cannot use dot notation to access nested values. To support dot
+    notation, cloud-init provides an alias by converting each hyphen (-) and period (.)
+    character to an underscore (_). This means that an instance launched with
+    ``-c user.special-key=1FE321`` can be queried using standard jinja notation,
+    ``cloud-init query --format "{{ds.config['user.special-key']}}"`` or may use the alias
+    notation ``cloud-init query --format "{{ds.config.user_special_key}}"`` or
+    ``cloud-init query ds.config.user_special_key``.
+
 
 Configuration
 =============