Intrinsic Functions
Intrinsic functions are functions that can be used within blueprints. Depending on the function, evaluation occurs on deployment creation or in runtime. During deployment creation, the “runtime only evaluation” flag can be set, which makes all functions be evaluated on-demand in runtime.
For example, the get_input intrinsic function is used to retrieve an input defined within the blueprint.
Intrinsic functions make blueprints dynamic, enabling the retrieval and setting of data structures in different parts of the blueprint.
get_secret
get_secret is used for referencing secrets described in the secrets API. get_secret can be used in node properties, outputs, node/relationship operation inputs, and runtime-properties of node instances. The function is evaluated at runtime.
Example:
node_templates:
host:
type: cloudify.nodes.Compute
properties:
ip: { get_secret: ip }
cloudify_agent:
key: { get_secret: agent_key }
user: { get_secret: user }
interfaces:
test_interface:
test_operation:
implementation: central_deployment_agent
inputs:
operation_input: { get_secret: operation_input }
outputs:
webserver_url:
description: Web server url
value: { concat: ['http://', { get_secret: ip }, ':', { get_secret: webserver_port }] }In this example, get_secret is used for completing several of the host node’s properties, as well as an operation input. In addition, it is used twice in the concatenated webserver_url output.
get_input
get_input is used for referencing inputs described in the inputs section of the blueprint. get_input can be used in node properties, outputs, and node/relationship operation inputs. The function is evaluated on deployment creation by default (unless the “runtime only evaluation” flag is set).
Example:
inputs:
webserver_port:
description: The HTTP web server port
default: 8080
vm_info:
description: The HTTP web server port
default:
key_name: 'my-openstack-key-name'
node_templates:
...
vm:
type: cloudify.openstack.nodes.Server
properties:
server:
image_name: { get_input: image_name }
key_name: { get_input: [ vm_info, key_name ] }
...
http_web_server:
type: cloudify.nodes.WebServer
properties:
port: { get_input: webserver_port }
relationships:
- type: cloudify.relationships.contained_in
target: vm
outputs:
webserver_port:
description: Web server port
value: { get_input: webserver_port }
vm_key_name:
description: Web server port
value: { get_input: [ vm_info, key_name ] }In the example, get_input is used for supplying the http_web_server node’s port property and the vm node’s key_name property. If on deployment creation the webserver_port input is not specified, get_input returns the default value of the webserver_port input.
Similarly, if the vm_info input is not specified, get_input returns the default value of the vm_info input.
get_capability
get_capability is used for referencing capabilities defined in other
deployments, as described in the capabilities
section of the blueprint.
get_capability can be used in node properties, outputs, and node/relationship operation inputs.
The function is evaluated at runtime. This means that the results of the
evaluation may differ according to their original values in the defining deployment.
Example:
First, we need to create a deployment that defines capabilities:
inputs:
some_input: some_value
node_types:
test_type:
derived_from: cloudify.nodes.Root
properties:
key:
default: default_value
dummy_type:
derived_from: cloudify.nodes.Root
properties:
input_property: { get_input: some_input }
node_templates:
node1:
type: test_type
node2:
type: test_type
properties:
key: override_value
dummy_node:
type: dummy_type
capabilities:
node_1_key:
value: { get_attribute: [ node1, key ]}
node_2_key:
value: { get_attribute: [ node2, key ]}
complex_capability:
value:
level_1:
level_2:
level_3: [ value_1, value_2 ]
key_1: value_3
key_2: value_4
input_capability:
value: { get_attribute: [ dummy_node, input_property ]We should note several things here:
capabilitiescan have complex values, with multiple layers (seecomplex_capability).- Other intrinsic functions can be used to define capabilities. Note that only
functions that are evaluated at runtime are allowed, so only
get_attribute,get_secretandconcatwill work, whileget_propertyandget_inputwill not. (unless the “runtime only evalution” flag is set).get_propertycan easily be replaced byget_attribute, so this isn’t really a limitation, however, if its is desirable to pass inputs as capabilities, a dummy node instance can be created, and thenget_attributecan be deployed to retrieve it (seeinput_capability)
Let’s assume now that a deployment with the ID shared was created from
the above blueprint. Let’s now create a second deployment to utilize the
get_capability intrinsic function:
node_types:
test_type:
derived_from: cloudify.nodes.Root
properties:
key:
default: { get_capability: [ shared, node_1_key ] }
node_templates:
node1:
type: test_type
node2:
type: test_type
properties:
key: { get_capability: [ shared, node_2_key ] }
outputs:
complex_output:
value: { get_capability: [ shared, complex_capability ] }
nested_complex_output:
value: { get_capability: [ shared, complex_capability, level_1, level_2, level_3, 0 ] }Here we can see how get_capability is used - the input to the function
is a list with at least 2 values: the ID of the deployment, the name of the
capability and optionally nested attributed/list indices, as defined in the shared blueprint.
Note that both the deployment ID and the capability name can be provided
using other intrinsic functions (e.g. get_input or get_secret). So, in case
the deployment ID is not known in advance, we could do something like this:
outputs:
some_output:
value: { get_capability: [ { get_secret: shared_deployment_id }, complex_capability ] }get_environment_capability
get_environment_capability is an alias for using { get_capabilities: [ {get_label: csys-obj-parent,0}, CAPABILITY_NAME]}
where we can get the environment capabilities of the environment that blueprint is referencing.
get_environment_capability can be used in node properties, outputs, and node/relationship operation inputs.
The function is evaluated at runtime. This means that the results of the
evaluation may differ according to their original values in the defining deployment.
Example:
First, we need to create a deployment that defines capabilities:
inputs:
some_input: some_value
node_types:
test_type:
derived_from: cloudify.nodes.Root
properties:
key:
default: default_value
dummy_type:
derived_from: cloudify.nodes.Root
properties:
input_property: { get_input: some_input }
node_templates:
node1:
type: test_type
node2:
type: test_type
properties:
key: override_value
dummy_node:
type: dummy_type
capabilities:
node_1_key:
value: { get_attribute: [ node1, key ]}
node_2_key:
value: { get_attribute: [ node2, key ]}
complex_capability:
value:
level_1:
level_2:
level_3: [ value_1, value_2 ]
key_1: value_3
key_2: value_4
input_capability:
value: { get_attribute: [ dummy_node, input_property ]Let’s assume now that a deployment with the ID shared was created from
the above blueprint. Let’s now create a second deployment to utilize the
get_environment_capability intrinsic function and we need to make sure
that deployment has csys-obj-parent label that matches name of
the first deployment (environment) shared.
labels:
csys-obj-parent:
values:
- shared
node_types:
test_type:
derived_from: cloudify.nodes.Root
properties:
key:
default: { get_capability: [ shared, node_1_key ] }
node_templates:
node1:
type: test_type
node2:
type: test_type
properties:
key: { get_capability: [ shared, node_2_key ] }
outputs:
complex_output:
value: { get_environment_capability: complex_capability }
nested_complex_output:
value: { get_environment_capability: [ complex_capability, level_1, level_2, level_3, 0 ] }get_property
get_property is used for referencing node properties within a blueprint. get_property can be used in node properties, outputs, and node/relationship operation inputs. The function is evaluated on deployment creation by default (unless the “runtime only evaluation” flag is set).
Usage and Examples
get_property in node properties and interface operation inputs
node_templates:
security_group:
type: cloudify.openstack.nodes.SecurityGroup
properties:
rules:
- remote_ip_prefix: 0.0.0.0/0
port: { get_property: [web_server, port] }
web_server:
type: cloudify.nodes.WebServer
properties:
port: 80
interfaces:
cloudify.interfaces.lifecycle
create:
...
configure:
implementation: some_plugin.tasks.configure
inputs:
port: { get_property: [SELF, port] }In the example, get_property is used for specifying a security group’s rule port as the web_server node’s port. In addition, get_property is used for passing the web_server’s port property as an input to the configure operation. The keyword SELF is used for specifying that the referenced property belongs to the current node. In this case, using web_server instead of SELF provides the same outcome.
get_property in relationship interface operation inputs:
node_templates:
db_server:
type: cloudify.nodes.DBMS
properties:
endpoint: 10.0.0.1:3376
web_server:
type: cloudify.nodes.WebServer
properties:
port: 8080
relationships:
- target: db_server
type: cloudify.relationships.connected_to
source_interfaces:
cloudify.interfaces.relationship_lifecycle:
preconfigure:
implementation: some_plugin.tasks.my_preconfigure
inputs:
db_endpoint: { get_property: [TARGET, endpoint] }
webserver_port: { get_property: [SOURCE, port] }In this example, get_property is used to reference the source and target nodes’ properties. The SOURCE and TARGET keywords can only be used in a relationship interface.
get_property in outputs:
node_templates:
web_server
type: cloudify.nodes.WebServer
properties:
port: 80
outputs:
web_server_id:
description: Web server port
value: { get_property: [web_server, port] }get_property Nested Properties and Complex Structures
It is possible to reference nested properties within dictionaries/hashes and lists in any nesting level. To access a property within a list, the index of the item must be specified. To access values in a dictionary/hash, a key must be specified.
node_templates:
vm:
type: cloudify.nodes.Compute
properties:
ip_addresses:
- 192.168.0.7
- 15.67.45.29
web_server:
type: cloudify.nodes.WebServer
properties:
endpoint:
type: http
port: 80
relationships:
- target: vm
type: cloudify.relationships.contained_in
source_interfaces:
cloudify.interfaces.relationship_lifecycle:
preconfigure:
implementation: some_plugin.tasks.my_preconfigure
inputs:
public_ip: { get_property: [TARGET, ip_addresses, 1] }
endpoint_type: { get_property: [SOURCE, endpoint, type] }get_attribute
get_attribute is used to reference runtime-properties of different node-instances from within a blueprint.
Usage and Examples
get_attribute in outputs
For this example, assume a webserver_id runtime property has been set on the web_server instance.
node_templates:
web_server
type: cloudify.nodes.WebServer
outputs:
web_server_id:
description: Web server ID
value: { get_attribute: [web_server, webserver_id] }In the example, the web_server_id deployment output is configured to reference the web_server runtime property webserver_id. Each time the deployment outputs are evaluated, the reference is replaced with its current value.
get_attribute in Node Interface Operation Inputs
For this example, assume a connection_url runtime property has been set on the db_server instance and a requested_version runtime property has been set on the web_server instance.
node_templates:
db_server:
type: cloudify.nodes.DBMS
web_server:
type: cloudify.nodes.WebServer
interfaces:
cloudify.interfaces.lifecycle
create:
...
configure:
implementation: some_plugin.tasks.configure
inputs:
db_connection_url: { get_attribute: [db_server, connection_url] }
webserver_version: { get_attribute: [SELF, requested_version] }In the example, each time the configure operation of web_server instances is invoked, the inputs db_connection_url and webserver_version are evaluated. The db_connection_url input evaluates to the db_server runtime property connection_url, and the webserver_version evaluates to the web_server runtime property requested_version. SELF is used to reference run-time properties of the current node instance in webserver_version.
get_attribute in Relationship Interface Operation Inputs
For this example, assume a connection_url runtime property has been set on the db_server instance and a requested_version runtime property has been set on the web_server instance.
node_templates:
db_server:
type: cloudify.nodes.DBMS
web_server:
type: cloudify.nodes.WebServer
relationships:
- target: db_server
type: cloudify.relationships.connected_to
source_interfaces:
cloudify.interfaces.relationship_lifecycle:
preconfigure:
implementation: some_plugin.tasks.my_preconfigure
inputs:
db_connection_url: { get_attribute: [TARGET, connection_url] }
webserver_version: { get_attribute: [SOURCE, requested_version] }In the example, each time the preconfigure relationship operation is invoked, the inputs db_connection_url and webserver_version are evaluated. The db_connection_url input evaluates to the db_server runtime property connection_url. The webserver_version evaluates to the web_server runtime property requested_version. SOURCE and TARGET are used to reference the relationship source and target node instances respectively.
get_attribute Nested Properties and Complex Structures
Attribute access may be nested and is not restricted to top-level properties. In this example, assume a webserver_spec runtime property has been set on the web_server instance with this value:
{
"requested_version": "11.2",
"alternative_versions": ["11.3", "12.0"],
"endpoints": {
"endpoint_1": {
"description": "An endpoint of the web server",
"url": "/endpoint1"
},
"endpoint_2": {
"description": "Another endpoint of the web server",
"url": "/endpoint2"
}
}
}With this value in place, nested properties can be accessed as follows:
outputs:
alt_version1:
# evaluates to "12.0"
value: { get_attribute: [web_server, webserver_spec, alternative_version, 1] }
enpoint_2_url:
# evaluates to "/endpoint2"
value: { get_attribute: [web_server, webserver_spec, endpoints, endpoint_2, url] }
partial_spec:
value:
version: { get_attribute: [web_server, webserver_spec, requested_version] }
alt_versions:
version1: { get_attribute: [web_server, webserver_spec, alternative_versions, 0] }
version2: { get_attribute: [web_server, webserver_spec, alternative_versions, 1] }Notice that nested properties can be either a key name in the case of a map, or an index in case of a list. Also note in partial_spec that get_attribute can be used in complex data structures and not only in a flat key/value manner.
get_attribute to get Node Instance ID
Use get_attribute to retrieve the ID of a node instance:
{ get_attribute: [node, node_instance_id] }node can be SELF, SOURCE, TARGET or node name according to the context in the blueprint.
get_attribute Between Members of Shared Scaling Groups
In general, get_attribute cannot be used with an explicit reference (i.e. specifying a node name directly) when more than one node instance matching the specified node exists.
If however, the referenced node shares a scaling group with the referencing node, the ambiguity may be resolved.
Resolving the ambiguity for get_attribute usages in the blueprint outputs is not supported.
Following is a more detailed explanation, followed by an example.
The term referencing node depends on where in the blueprint, get_attribute is used. If it is used in a node operation’s inputs (e.g. cloudify.interfaces.lifecycle.start), referencing node is the node template under which the operation is defined. If get_attribute is used in a relationship operation’s inputs (e.g. cloudify.interfaces.relationship_lifecycle.establish), referencing node is actually referencing nodes, which are the source and target nodes in the relationship operation. Both can be used as a referencing node, and the first to resolve the ambiguity is used.
Consider the case in which A is the referencing node and B the referenced node. If A and B belong to a scaling group, and that scaling group’s instances contain only one instance of B, get_attribute resolves to using that B’s instance when evaluating the get_attribute.
For example:
node_templates:
db_server:
type: cloudify.nodes.DBMS
web_server:
type: cloudify.nodes.WebServer
interfaces:
cloudify.interfaces.lifecycle
configure:
implementation: some_plugin.tasks.configure
inputs:
# Here, the referencing node is the web_server and the referenced
# node is the db_server
db_connection_url: { get_attribute: [db_server, connection_url] }
relationships:
- target: db_server
type: cloudify.relationships.connected_to
source_interfaces:
cloudify.interfaces.relationship_lifecycle:
preconfigure:
implementation: some_plugin.tasks.my_preconfigure
inputs:
# Here, the referencing nodes are web_server and db_server and the
# referenced node is db_server (a node can reference itself)
db_connection_url: { get_attribute: [db_server, connection_url] }
groups:
db_and_webserver:
members: [db_server, web_server]
policies:
scaling_policy1:
type: cloudify.policies.scaling
properties:
default_instances: 2
targets: [db_and_webserver]The blueprint example defines an application with one scaling group db_and_webserver that initially has two instances. Each group instance contains one db_server node instance and one web_server node instance. Both usages of get_attribute will correctly resolve to the node instance that is together with the referencing node instance in the same scaling group instance.
If a node template is contained in another node template (for example, a Webserver contained in a VM), and the containing node template is a member in a scaling group, the contained node instance is implicilty a member of the same scaling group.
Using this, you can define a scaling group containing one node (for example, a compute node).
All nodes transitively contained in that compute node can reference each other using an explicit get_attribute (reference by node name), even if the compute node has several instances (if the compute node is scaled using its scaling group and not directly). This is possible because they all implicitly belong to the same scaling group instance (that of the compute node instance containing them).
Notes, Restrictions and Limitations
- If an attribute is not found in the inspected node instance runtime properties, the scan resorts to the matching node properties. If the attribute is also not found in the node properties,
nullis returned. SELFmay only be used in interface operation inputs.SOURCEandTARGETmay only be used in relationship interface operation inputs.
When using get_attribute with an explicit reference, that is, a node’s name { get_attribute: [ web_server, webserver_spec ] } and not an implicit reference such as { get_attribute: [ SELF, webserver_spec ] } the following limitation exists.
If, at the time of evaluation, more than one node instance with that name exists and the ambiguity cannot be resolved as described in the previous section, an error is returned.
This limitation has significant implications when using get_attribute in node/relationship operation inputs, because it means the operation cannot be executed.
get_attributes_list
get_attributes_list is used to reference runtime-properties of all node instances of a target node from within a blueprint.
Usage and Examples
get_attributes_list general behaviour
get_attributes_list behaviour is the same as get_attribute in most respects- e.g. with regards to evaluation always resulting in the current values and the behaviour with nested structures.
The behaviour differs in that get_attributes_list will always return a list of the target attribute for all node instances belonging to the target node. Therefore, it is usable with nodes with multiple instances without needing to be part of a scaling group.
Notes, Restrictions and Limitations
These are identical to the get_attribute function with the exception that there is no limitation regarding a target node’s instance count.
If any node instances are missing the requested attribute, a null will be added to the list for that node instance (unless the node itself has the property per the lookup rules noted under get_attribute).
If there are no node instances an empty list will be returned.
List ordering should not be considered deterministic.
Example
For this example, assume an ip runtime property has been set on each web_server instance.
node_templates:
web_server
type: cloudify.nodes.WebServer
instances:
deploy: 3
outputs:
web_server_ips:
description: Web server IPs
value: { get_attributes_list: [web_server, ip] }Before the web servers have had their IPs set, the web_server_ips output will return [null, null, null].
If two of the web servers have had their IPs set, the web_server_ips output will be ["192.0.2.2", "192.0.2.1", null] (assuming those IPs were set in the runtime properties).
When all three have had their IPs set, the web_server_ips output will be ["192.0.2.2", "192.0.2.1", "192.0.2.3"] (assuming those IPs were set in the runtime properties).
get_attributes_dict
get_attributes_dict is used to reference multiple runtime-properties of all node instances of a target node from within a blueprint.
Usage and Examples
get_attributes_dict general behaviour
get_attributes_dict behaviour is the same as get_attribute in most respects- e.g. with regards to evaluation always resulting in the current values and the behaviour with nested structures.
The behaviour differs in that get_attributes_dict will always return a dictionary of the target attributes for all node instances belonging to the target node. Therefore, it is usable with nodes with multiple instances without needing to be part of a scaling group.
The dictionary is keyed on node instance ID, with each of those entries having a value of a dict with keys of the attributes being sought and values of those attributes for the relevant node instance.
If a nested attribute is requested, the key for the results for that attribute will be formed by joining the nested attribute name together with dots. For example, if you request [myattrib, nest1, nest2] then the key will be myattrib.nest1.nest2. If this name collides with another requested attribute name an error will be raised.
The order of the returned data should not be considered deterministic.
See the example at the end of this section for more details.
Notes, Restrictions and Limitations
These are identical to the get_attribute function with the exception that there is no limitation regarding a target node’s instance count.
If any node instances are missing any of the requested attribute, a null will be added as the value of that attribute for that node instance (unless the node itself has the property per the lookup rules noted under get_attribute).
If there are no node instances an empty dict will be returned.
Example
For this example, assume an ip runtime property has been set on each web_server instance, as a dict with a v4 key in it, as well as a separate url attribute.
Also, assume the webserver node instance IDs are web_server_abcde1, web_server_abcde2, web_server_abcde3.
node_templates:
web_server
type: cloudify.nodes.WebServer
instances:
deploy: 3
outputs:
web_server_details:
description: Web server details
value: { get_attributes_dict: [web_server, [ip, v4], url] }Before the web servers have had their IPs set, the web_server_details output will return {"web_server_abcde1": {"ip.v4": null, "url": null}, "web_server_abcde3": {"ip.v4": null, "url": null}, "web_server_abcde2": {"ip.v4": null, "url": null}.
If two of the web servers have had their IPs set, and one has its url set the web_server_details output will be {"web_server_abcde1": {"ip.v4": "192.0.2.5", "url": null}, "web_server_abcde3": {"ip.v4": "192.0.2.54", "url": "/api"}, "web_server_abcde2": {"ip.v4": null, "url": null} (assuming those IPs and urls were set in the runtime properties).
When all three have had their IPs and urls set, the web_server_details output will be {"web_server_abcde1": {"ip.v4": "192.0.2.5", "url": "/api"}, "web_server_abcde3": {"ip.v4": "192.0.2.54", "url": "/api"}, "web_server_abcde2": {"ip.v4": "192.0.2.120", "url": "/api"} (assuming those IPs and urls were set in the runtime properties).
get_label
get_label is used for referencing labels assigned to the deployment generated from the blueprint.
Labels can be provided while creating the deployment, or in the labels section of the blueprint.
get_label can be used in node properties, outputs,
node/relationship operation inputs, and runtime-properties of node instances.
The function is evaluated at runtime.
The get_label function can be used in one of the two ways:
* { get_label: <label_key> }: This function returns a list of all values associated with the specified key, sorted by their creation time and alphabetical order.
* { get_label: [<label_key>, <values_list_index>] }: This function first gathers all values associated with the specified key,
sorts them by their creation time and alphabetical order, and then returns the value in the specified index.
Note: The creation time of all labels created during the deployment creation, whether provided in the labels section of the blueprint or
as part of the deployment parameters, is the same. The order of the values in the labels section does not matter.
In the example below, we assume the user created a deployment with the name shared, that has the capability node_1_key1.
Example:
labels:
csys-obj-parent:
values:
- shared
environment:
values:
- aws
node_types:
test_type:
derived_from: cloudify.nodes.Root
properties:
key:
default: default_key
node_templates:
node1:
type: test_type
properties:
key: { get_capability: [ { get_label: [csys-obj-parent, 0] }, node_1_key ] }
outputs:
environment_output:
value: { get_label: [environment, 0] }get_sys
The get_sys is used to retrieve the following tenant’s and deployment’s properties. * tenant’s name * deployment’s id, owner user name and the id of the blueprint the deployment is created from.
Syntax
One of following properties can be retrieved:
get_sys: [tenant, name],get_sys: [deployment, id],get_sys: [deployment, owner],get_sys: [deployment, blueprint].
string_find
Used to find the lowest index in the string where substring is found. Return -1 if substring is
not found.
Syntax
string_find: [haystack, needle] is basically an equivalent of Python’s haystack.find(needle). Return the lowest index in the string where substring sub is found within the slice s[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 if sub is not found.
Example
node_templates:
node1:
type: test_type
properties:
some_number: { string_find: [ 'Lorem ipsum dolor sit amet', 'dolor' ] }some_number property will become 12.
string_replace
Used to replace all occurrences of a substring with another string.
Syntax
string_replace: [haystack, needle, replacement] is an equivalent of Python’s
haystack.replace(needle, replacement).
string_replace: [haystack, needle, replacement, count] is basically an equivalent of Python’s
haystack.replace(needle, replacement, count).
Example
Convert a full path to relative path by removing only the first slash Change the domain from local to an external
node_templates:
node1:
type: test_type
properties:
path: { string_replace: [ '/app/profile', '/', '' , 1] }
fqdn: { string_replace: [ 'host.local', '.local', '.example.com' ] }path property will become 'app/profile'.
fqdn property will become 'host.example.com'.
string_split
Used to split a string using a delimiter string. In case a third argument is provided, it defines an index of that array, which will be returned.
Syntax
string_split: [input, sep] is an equivalent of Python’s input.split(sep).
string_split: [input, sep, index] is Python’s input.split(sep)[index].
Example
Convert space separated string into a lists Get the host portion out of a full domain name
node_templates:
node1:
type: test_type
properties:
users_array: { string_split: [ 'John Anna Dana Fred', ' ' ] }
hostname: { string_split: [ 'host1.example.com', '.', 0 ] }users_array property will become a list ['John', 'Anna', 'Dana', 'Fred'],
hostname property will become string 'host1'.
string_lower
Modify a string such as it has the cased characters converted to lowercase.
Syntax
string_lower: input is basically an equivalent of Python’s input.lower().
Example
node_templates:
node1:
type: test_type
properties:
some_string: { string_lower: 'Lorem ipsum dolor sit AMET' }some_string property will become 'lorem ipsum dolor sit amet'.
string_upper
Modify a string such as it has the cased characters converted to uppercase.
Syntax
string_upper: input is basically an equivalent of Python’s input.upper().
Example
node_templates:
node1:
type: test_type
properties:
some_string: { string_upper: 'Lorem ipsum dolor sit AMET' }some_string property will become 'LOREM IPSUM DOLOR SIT AMET'.
concat
concat is used for concatenating strings in different sections of a blueprint. concat can be used in node properties, outputs, and node/relationship operation inputs. The function is evaluated once on deployment creation, which replaces get_input and get_property usages. It is also evaluated on every operation execution and outputs evaluation, to replace usages of get_attribute.
Example
node_templates:
...
http_web_server:
type: cloudify.nodes.WebServer
properties:
port: 8080
# This will evaluate to 'http://localhost:8080' during deployment creation
local_endpoint: { concat: ['http://localhost:', { get_property: [SELF, port] }] }
interfaces:
cloudify.interfaces.lifecycle:
configure: scripts/configure.sh
start:
implementation: scripts/start.sh
inputs:
process:
env:
port: { get_input: webserver_port }
# This will evaluate to 'http://192.168.12.12:8080' before the 'start'
# operation execution, assuming `the_vm` private ip address is 192.168.12.12
internal_endpoint: { concat: ['http://', { get_attribute: [the_vm, ip] },
':', { get_property: [SELF, port] }] }
stop: scripts/stop.sh
outputs:
external_endpoint:
description: Web server external endpoint
# This will evaluate to 'http://15.16.17.18:8080' every time outputs are evaluated
# assuming `the_floating_ip` address is 15.16.17.18
value: { concat: ['http://', { get_attribute: [the_foating_ip, floating_ip_address] },
':', { get_property: [http_web_server, port] }] }merge
merge is used to merge dictionaries. It is similar to contact with respect to when it can be used, and when
it is evaluated.
It accepts a list of dictionaries (each one may be static, or dynamically interpreted using other intrinsic functions), and returns a dictionary that contains a merge of these dictionaries.
If a particular key exists in more than one of the provided dictionaries, the last one prevails.
Example
node_templates:
...
repository:
type: example.types.Repository
properties:
resource_config:
key1: value1
key2: value2
interfaces:
cloudify.interfaces.lifecycle:
start:
implementation: scripts/start.py
inputs: { merge: [ { get_property: [ SELF, resource_config], { key3: value3 } } ] }In runtime, the scripts/start.py script will receive the following inputs:
key1: value1
key2: value2
key3: value3Intrinsic Functions as arguments of other Intrinsic Functions
Intrinsic Functions can be passed as arguments of other Intrinsic Functions. For example, you may write this in your blueprint:
node_templates:
...
http_web_server:
type: cloudify.nodes.Compute
properties:
# The parser will first evaluate the result of the inner `get_input` and
# then using it's result, will evaluate the outter get_input.
# If the input available_ports = [8000, 8080] and web_server_port_no = 0,
# then http_web_server.port = 8000.
port: { get_input: [ available_ports, { get_input: web_server_port_no } ] }
...The arguments of a static function (e.g. get_input, get_property) may not contain any runtime function (e.g. get_attribute, get_secret).
You may also note that function concat for example is neither static or runtime, therefore it may be passed as an argument to a static function as long as
it doesn’t contain runtime functions.
For example this is OK: ✓
node_templates:
…
outputs:
some_output:
value:
{ get_input:
{ concat: [ { get_property: [ server1, protocol_prefix ] },
{ get_property: [ server1, preset_ip_addr ] } ] }}
…
This is not OK (a runtime function get_attribute within a static function get_input): ✘
node_templates:
…
outputs:
some_output:
value:
{ get_input:
{ concat: [ { get_property: [ server1, protocol_prefix ] },
{ get_attribute: [ server1, ip_addr ] } ] }}
…
