WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
License for the specific language governing permissions and limitations
under the License.
-
+==================
Built in functions
==================
All of these functions (except *Ref*) start with *Fn::*.
-
+---
Ref
---
Return the value of the named parameter or Resource.
Parameters
~~~~~~~~~~
-**Name**: the name of the Resource or Parameter.
+name : String
+ The name of the Resource or Parameter.
Usage
~~~~~
{Ref: my_server}
-Returns
-~~~~~~~
-::
-
- instance-0003
+Returns ``instance-0003``
+----------
Fn::Base64
----------
This returns the Base64 representation of the input string.
Parameters
~~~~~~~~~~
-**String**: the string to convert.
+value : String
+ The string to convert.
Usage
~~~~~
{Base64: "convert this string please."}
-Returns
-~~~~~~~
-Base64 of the input string.
+Returns the Base64 of the input string.
+-------------
Fn::FindInMap
-------------
-returns the value corresponding to keys into a two-level map declared in the Mappings section.
+Returns the value corresponding to keys into a two-level map declared in the
+Mappings section.
Parameters
~~~~~~~~~~
-**MapName**: The logical name of a mapping declared in the Mappings section that contains the keys and values.
+map_name : String
+ The logical name of a mapping declared in the Mappings section that
+ contains the keys and values.
-**TopLevelKey**: The top-level key name. It's value is a list of key-value pairs.
+top_level_key : String
+ The top-level key name. It's value is a list of key-value pairs.
-**SecondLevelKey**: The second-level key name, which is set to one of the keys from the list assigned to TopLevelKey.
+second_level_key : String
+ The second-level key name, which is set to one of the keys from the list
+ assigned to top_level_key.
Usage
~~~~~
::
+
Mapping:
MyContacts:
jone: {phone: 337, email: a@b.com}
{"Fn::FindInMap": ["MyContacts", "jim", "phone" ] }
-Returns
-~~~~~~~
-
-In the case above it will return **908**
+Returns ``908``
+----------
Fn::GetAtt
----------
Returns an attribute of a Resource within the template.
Parameters
~~~~~~~~~~
-**Resource**: the name of the Resource.
+resource : String
+ The name of the Resource.
-**Attribute**: the name of the attribute.
+attribute : String
+ The name of the attribute.
Usage
~~~~~
{Fn::GetAtt: [my_server, PublicIp]}
-Returns
-~~~~~~~
-In the case above it would return an Ipaddress like **10.0.0.2**
+Returns an IP address such as ``10.0.0.2``
+----------
Fn::GetAZs
----------
Return the Availablity Zones within the given region.
Parameters
~~~~~~~~~~
-region: the name of the region.
+region : String
+ The name of the region.
Usage
~~~~~
{Fn::GetAZs: ""}
-Returns
-~~~~~~~
-This returns what nova returns from availablity_zones.list()
+Returns the list provided by ``nova availability-zone-list``
+--------
Fn::Join
--------
Like python join, it joins a list of strings with the given delimiter.
Parameters
~~~~~~~~~~
-**delimiter**: a string to join the list with.
+delimiter : String
+ The string to join the list with.
-**list**: a list of strings
+list : list
+ The list to join.
Usage
~~~~~
{Fn::Join: [",", ["beer", "wine", "more beer"]]}
-Returns
-~~~~~~~
-
-The above example would return "beer, wine, more beer".
+Returns ``beer, wine, more beer``
+----------
Fn::Select
----------
Select an item from a list.
-*Heat extension: Select an item from a dict*
+*Heat extension: Select an item from a map*
Parameters
~~~~~~~~~~
-Selector: the number of item in the list or the name of the item in
-the dict.
+selector : string or integer
+ The number of item in the list or the name of the item in
+the map.
+collection : map or list
+ The collection to select the item from.
Usage
~~~~~
+For a list lookup:
::
- (for a list lookup)
+
{ "Fn::Select" : [ "2", [ "apples", "grapes", "mangoes" ] ] }
- returns "mangoes"
+Returns ``mangoes``
+
+For a map lookup:
+::
- (for a dict lookup)
{ "Fn::Select" : [ "red", {"red": "a", "flu": "b"} ] }
- returns "a"
+Returns ``a``
+---------
Fn::Split
---------
This is the reverse of Join. Convert a string into a list based on the
Parameters
~~~~~~~~~~
-**delimiter**: a string.
+delimiter : string
+ Matching string to split on.
-**string**: the string to split.
+string : String
+ The string to split.
Usage
~~~~~
::
{ "Fn::Split" : [ ",", "str1,str2,str3,str4"]}
- returns
- {["str1", "str2", "str3", "str4"]}
+Returns ``{["str1", "str2", "str3", "str4"]}``
+
+-----------
Fn::Replace
-----------
Find an replace one string with another.
Parameters
~~~~~~~~~~
-**subsitutions**: a map of subsitutions.
-
-**string**: the string to do the substitutions in.
+subsitutions : map
+ A map of subsitutions.
+string: String
+ The string to do the substitutions in.
Usage
~~~~~
returns
"foo is bar"
-
+------------------
Fn::ResourceFacade
------------------
When writing a Template Resource:
Parameters
~~~~~~~~~~
-Attribute Name: one of Metadata, DeletionPolicy or UpdatePolicy.
+attribute_name : String
+ One of ``Metadata``, ``DeletionPolicy`` or ``UpdatePolicy``.
Usage
~~~~~
::
+
{'Fn::ResourceFacade': 'Metadata'}
{'Fn::ResourceFacade': 'DeletionPolicy'}
{'Fn::ResourceFacade': 'UpdatePolicy'}
Example
~~~~~~~
-Here is a top level template (top.yaml)
+Here is a top level template ``top.yaml``
::
+
resources:
my_server:
type: OS::Compute::Server
some: more stuff
-Here is a resource template (my_actual_server.yaml)
-
+Here is a resource template ``my_actual_server.yaml``
::
+
resources:
_actual_server_:
type: OS::Compute::Server
- metadata: {Fn:ResourceFacade metadata}
-
-my environment (env.yaml)
+ metadata: {'Fn::ResourceFacade': Metadata}
+The environment file ``env.yaml``
::
+
resource_registry:
resources:
my_server:
To use it
::
+
heat stack-create -f top.yaml -e env.yaml
-What happened is the metadata in top.yaml (key: value, some: more
-stuff) gets passed into the resource template via the **Fn::ResourceFacade**
+What happened is the metadata in ``top.yaml`` (key: value, some: more
+stuff) gets passed into the resource template via the `Fn::ResourceFacade`_
function.
Code Review / openstack-build / heat-build.git / commitdiff