Functions Overview
Functions are built-in operations that execute inside the Cloud Workflow engine using RightScale Cloud Workflow Language (RCL). They provide various helpers to address needs like retrieving the current time, generating random numbers, sorting collections and arrays, etc. Functions may operate on values and/or on reference collections and return values and/or reference collections. Arguments passed to functions are read-only. For example, the sort()
function will return the result of the sort rather than modify the argument. Functions use the lower_case()
notation.
Collections Management
The first category of functions relate to managing resource collections and arrays of values.
find
Syntax
find($type, $name or $hash[, $revision])
Description
This function is syntactic sugar around the resource type get()
action. It is the equivalent of calling the get()
action with the given filters and returning the first resource that matches. Filters are specified with a hash or with a string and optional integer. If a string is specified then it is equivalent to a having a hash with a key name and the associated value (i.e. by default filter on name). If a integer is specified then is it equivalent to having a hash with a key revision. So:
@servers = find("servers", "default")
@servers = find("servers", { name: "default" })
are equivalent to:
@servers = first(rs.servers.get(filter: ["name==default"]))
and
@server_template = find("server_templates", "MySQL Database Manager", 137)
@server_template = find("server_templates", { name: "MySQL Database Manager", revision: 137 })
are equivalent to:
@server_template = first(rs.server_templates.get(filter: ["name==MySQL Database Manager","revision==137"]))
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string | yes | none | Resource type, e.g. servers , deployments , etc. |
2 | string or hash | yes | none | Resource name or filters |
3 | string or integer | no | none | Resource revision, if resource is versioned. Not specifying a value for versioned resources returns all resources with the given type and name. |
Result
A resource collection containing the first resource matching the given filter if any.
size
Syntax
size($array, $hash, $string or @collection)
Description
This function simply returns the size of the resource collection or array of values given as argument.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values or hash of values or string | yes | none |
Result
An integer representing the size of the given array, hash, string or collection.
first and last
Syntax
first($array or @collection)
and last($array or @collection)
Description
These functions simply retrieve the first or last element of a resource collection or array of values.
Note: For resource collections, the result is a resource collection itself, consisting of a single resource. However, for an array of values, the result is a single value.
Arguments
The only argument is the collection from which the first or last element should be extracted.
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values | yes | none |
Result
A resource collection if the argument is a resource collection or a value if the argument is an array of values.
Examples
$one = first([1, 2, 3]) # $one == 1
@servers = rs.deployments.get(filter: ["name==default"]).servers()
@first = first(@servers) # size(@first) == 1
sort
Syntax
sort($array or @collection[, $field][, $order])
Description
The sort()
function allows sorting resource collections and arrays of values. If sorting an array of values, then all values must be of the same type and the array must not contain null
. The ordering follows the same logic as the comparison operators:
- Numbers and datetime use the natural order (think of datetime in terms of seconds since the epoch for comparison)
- Strings and arrays follow the lexicographical order
- true > false
Hashes cannot be compared directly, instead the sort()
function accepts an argument to specify recursively which key should be used for sorting. That same argument can be used on resource collections to specify which field should be used for sorting. If the field ends up being a hash, then recursively what key of the hash should be used. By default, sorting resource collections is done using the name
field.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values | yes | none | collection to be sorted |
2 | string | only if collection is an array of hashes | name for resource collections |
name of resource field used to order resource collections or name of key of hash to be used to order for array of hashes the definition is recursive, each key being separated with the character / |
3 | asc or desc |
no | asc |
Sorting order (ascendant or descendant) |
Result
The result type is the same as the first argument: a resource collection or an array of values.
Examples
Sorting a resource collection by name:
@servers = rs.deployments.get(filter: "name==default").servers()
@sorted_servers = sort(@servers)
Sorting a collection of instances by their user data descending:
@instances = rs.deployments.get(filter: "name==default").server().current_instance()
@sorted_instances = sort(@instances, "settings/user_data", "desc")
Sorting an array of hashes (using a key called timestamp in this example):
$data = [{ "value": 42, "timestamp": d"1/1/2012 12:32" },
{ "value": 43, "timestamp": d"1/1/2012 16:31" }]
$sorted_data = sort($data, "timestamp")
contains
Syntax
contains?($array or @collection, elements)
Description
This function checks whether all the elements of a given collection or a specific value are contained in another given collection. The elements may be in different order and they may appear a different number of times, but as long as all elements appear at least once, then the function returns true
, otherwise it returns false
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values | yes | none | Container being tested |
2 | resource collection or array of values | yes | none | Elements that must be in container for function to return true |
Result
true
if all elements are contained in given collection, false
otherwise.
Examples
$array = [1, 2, 3, 4]
contains?($array, [1]) == true
contains?($array, [5]) == false
contains?($array, [2, 1, 3, 3]) == true
contains?($array, [1, 2, 3, 5]) == false
@servers = rs.deployments.get(filter: "name==default").servers()
@server = rs.get(href: "servers/123") # Assume this server belongs to a deployment named 'default'
contains?(@servers, @server) == true
empty
Syntax
empty?($array or @collection)
Description
Returns true
if the given collection (resource collection or array of values) is empty, false
otherwise.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values | yes | none |
Result
true
if given collection is empty, false
otherwise.
any
Syntax
any?($array[, $value_or_regexp])
Description
This function checks for the existence of an element in an array of JSON values. When only an array is given then returns true
if the array contains a value that is neither null
nor false
. When both an array and a value are provided then returns true
if the array contains at least once the given value. If the value is a regular expression, it will return true
if there is a least one value that is a string and that matches the regexp. The syntax used to write a regular expressions is /regexp/
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | array of values | yes | none | |
2 | value or regular expression | no | none |
Result
true
or false
.
Examples
$array_of_false = [false, false, null]
any?($array_of_false) == false # All elements are null or false, result is false
$array = [1, 2, 3, "a", "b", "cde"]
any?($array) == true # Array contains values that are not either false or null, result is true
any?($array, 1) == true # Array contains the value 1
any?($array, "cd") == false # Array does not contain value "cd"
any?($array, "/cd/") == true # Value "cde" matches regular expression "cd"
all
Syntax
all?($array[, $value_or_regexp])
Description
This function checks whether all elements of an array have a given value. When only an array is provided, then it returns true
if the array does not contain a value that is either null
or false
. When both an array and a value is provided, then it returns true
if the array values all match the given value. If the value is a regular expression, it will return true
if all the values in the array are all strings that match the regular expression. It returns true
if the array is empty.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | array of values | yes | none | |
2 | value or regular expression | no | none |
Result
true
or false
.
Examples
$array_with_one_false = [1, 2, false]
all?($array_with_one_false) == false # One element is null or false, result is false
$array = [1, 2, 3, "a", "b", "cde"]
all?($array) == true # Array contains no null or false, result is true
all?($array, 1) == false # Not all values are one
all?($array, "/cd/") == false # Not all values are strings that match regular expression "cd"
select
Syntax
select($array or @collection, $hash)
Description
This function extracts the elements of a resource collection or of an array of hashes that have fields or values with a given value. The name of the field or hash key that should be selected for comparison correspond to the keys of the hash given as second argument. The values of that hash are the values that the resource fields or hash entries must be selected. If the resource field or hash values are strings, then the selector hash value can represent regular expressions.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values | yes | none | Container being tested |
2 | hash | yes | none | Resource field names associated with value that should be filtered on or Hash key name associated with value that should be filtered on |
Result
A resource collection composed of resources that have fields with the given values or an array of hashes that have the given values for given keys.
Examples
@servers = rs.deployments.get(filter: "name==default").servers()
@app_servers = select(@servers, { "name": "/app/" }) # @app_servers contains servers whose name match
# the regular expression "app" (i.e. contain the string "app")
$hashes = [{ "key": "value1" }, { "key": "value2" }]
$hashes_with_value1 = select($hashes, { "key": "value1" }) # $hashes_with_value1 contains hashes whose values
# stored in key "key" is "value1"
unique
Syntax
unique($array or @collection)
Description
This function traverses the given collection and returns a new collection made of all the unique elements. Two resources are considered identical if they have the same href
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or array of values | yes | none | Container to be traversed and whose unique elements should be extracted |
Result
A collection composed of the distinct elements in the initial collection. The types of the elements is preserved (so the result is a resource collection or an array of values depending on the argument).
Examples
@servers = rs.deployments.get(filter: "name==default").servers()
@duplicated_servers = @servers + @servers
@unique_servers = unique(@duplicated_servers)
assert @servers == @unique_servers
Resource Management
The following functions help you to work with cloud resources. They are helper functions that encapsulate logic to help create and delete resources in a pre-defined way, saving you from having to implement the logic in your code.
provision
Syntax
provision(@declaration)
Description
This function provisions the resource passed in as a resource declaration. A resource declaration is a description of what a resource ought to be and consists of a hash which defines the resource namespace
, type
and fields
which characterize the resource.
The general behavior is that this function creates the resource and waits until it is in a usable state -- what exactly that means for each resource is a bit different. The following table lists the behavior of the provision function for each RightScale resource.
Resource | Behavior | Failure Behavior |
---|---|---|
Server | Create the Server Launch the Server Wait for the Server to become operational |
Terminate the Server Wait for the Server to terminate Delete the Server |
ServerArray | Create the ServerArray Enable the ServerArray Launch the ServerArray Wait for at least the min_count number of instances to become operational |
Terminate all instances in the ServerArray Wait for all instances to terminate Delete the ServerArray |
Instance | Create the Instance Launch the Instance Wait for the Instance to become running |
Terminate the Instance Wait for the Instance to terminate Delete the Instance |
IPAddress | Create the IPAddress | N/A |
IPAddressBinding | Create the IPAddressBinding | N/A |
Volume | Create the Volume Wait for the volume to become available |
Delete the Volume |
VolumeSnapshot | Create the VolumeSnapshot | N/A |
VolumeAttachment | Create the VolumeAttachment | N/A |
delete
Syntax
delete(@resource)
Description
This function cleans up and deletes the specified resource. Generally speaking, this function will take care to trigger the resource to be decommissioned and then remove the resource altogether -- the specific actions for each resource are a bit different. The following table lists the behavior of the delete function for each RightScale resource.
Resource | Behavior |
---|---|
Server | Terminate the Server Wait for the Server to terminate Delete the Server resource |
ServerArray | Disable the ServerArray Terminate all instances in the ServerArray Wait for all instances to terminate Delete the ServerArray |
Instance | Terminate the Instance Wait for the Instance to terminate Delete the Instance |
IPAddress | Delete the IPAddress |
IPAddressBinding | Delete the IPAddressBinding |
Volume | Delete the Volume |
VolumeSnapshot | Delete the VolumeSnapshot |
VolumeAttachment | Delete the VolumeAttachment |
Boolean Logic
The following set of functions all evaluate to true
or false
. They provide an alternate notation to using operators that may lend itself better when writing declarative code (e.g. when defining the fields of a declaration).
equals
Syntax
equals?($left or @left, $right or @right)
Description
This function checks whether both arguments are equals, it is equivalent to doing left == right
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or value | yes | none | |
2 | resource collection or value | yes | none |
Result
true
or false
.
Examples
$a = 1
$b = 2
$c = 1
equals?($a, $b) == false
equals?($a, $c) == true
switch
Syntax
switch($condition, @true_exp or $true_exp, @false_exp or $false_exp)
Description
This function evaluates the condition and returns either the true expression or false expression based on the value of $condition.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | value | yes | none | |
2 | resource collection or value | yes | none | |
3 | resource collection or value | yes | none |
Note: Both true expression and false expression should be of the same type.
Result
true expression or false expression
Examples
$anything_but_null = "foobar"
$false_or_null = null
switch($anything_but_null, $var1, $var2) == $var1
switch($false_or_null, @ec2, @google) == @google
logic_and and logic_or
Syntax
logic_and($left, $right)
and logic_or($left, $right)
Description
These functions apply the logical and or logical or operators respectively to their arguments. They are equivalent to $left && $right
and $left || $right
respectively.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | value | yes | none | |
2 | value | yes | none |
Result
true
or false
.
Examples
$anything_but_null = "foobar"
logic_and($anything_but_null, false) == false
logic_and($anything_but_null, true) == true
logic_and($anything_but_null, null) == false
logic_and(null, null) == false
logic_or($anything_but_null, false) == true
logic_or($anything_but_null, true) == true
logic_or($anything_but_null, null) == true
logic_or(null, null) == false
logic_not
Syntax
logic_not($value)
Description
Applies the logical not operator.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | value | yes | none |
Result
true
or false
.
Examples
logic_not(true) == false
logic_not(false) == true
$any_value_but_null = "foobar"
logic_not($any_value_but_null) == false
logic_not(null) == true
Data Conversion
The following set of functions are used to convert values from one type to another.
to_s
Syntax
to_s($value)
Description
Convert value to string. The semantic for each type is summarized in the following table:
Type | Result | Example |
---|---|---|
string | no change | to_s("foo") == "foo" |
number | string representation of number | to_s(1) == "1" |
boolean | string representation of boolean | to_s(true) == "true" |
datetime | string representation of datetime | to_s(d"1/1/2012 6:59 PM") == "d\"2012/01/01 18:59\"" |
null | string null |
to_s(null) == "null" |
array | JSON representation of an array | to_s([1, 2, "3"]) == "[1,2,\"3\"]" |
hash | JSON representation of a hash | to_s({ "one": 1, "two": 2, "three": 3 }) == "{\"one\":1,\"two\":2,\"three\":3}" |
to_n
Syntax
to_n($value)
Description
Convert a value to a number. The only types that can be converted to numbers are strings, booleans, and datetimes. Attempting to convert a value of a different type (e.g. an array) will result in an error.
Type | Result | Example |
---|---|---|
string | corresponding number or 0 if string does not represent a number | to_n("1.23123") == 1.23123 to_n("foo") == 0 |
number | no change | to_n(1) == 1 |
boolean | 1 for true, 0 for false | to_n(true) == 1 |
datetime | number of seconds since the epoch | to_n(d"2012/01/26 1:49:35") == 1327542575 |
null | 0 | to_n(null) == 0 |
to_b
Syntax
to_b($value)
Description
Convert value to boolean. The only types that can be converted to booleans are strings and numbers. Attempting to convert a value of a different type (e.g. an array) will result in an error.
Type | Result | Example |
---|---|---|
string | true if string is true, false otherwise |
to_b("true") == true to_b("foo") == false |
number | true if non 0, false otherwise |
to_b(42) == true to_b(0) == false |
boolean | no change | to_b(true) == true |
to_d
Syntax
to_d($value)
Description
Convert value to datetime. The only types that can be converted to datetimes are strings and numbers. Attempting to convert a value of a different type (e.g. an array) will result in an error. The accepted syntax for strings representing datetime is:
year/month/day [h:m[:s]] [AM|PM]
Trying to coerce a string that does not match this syntax to a datetime value results in an error.
Type | Result | Example |
---|---|---|
string | Corresponding datetime if syntax is correct, error otherwise | to_d("1/1/2012") == d"1/1/2012" |
number | datetime with corresponding unix timestamp | to_d(42) == d"1/1/1970 00:00:42" |
datetime | no change |
to_a
Syntax
to_a($value)
Description
Convert hash to array of pairs or a range to an array. Converting a value of type other than hash or range will result in an error.
Type | Result | Example |
---|---|---|
hash | Corresponding array of pairs, ordering is random | to_a({ "one": 1, "two": 2, "three": 3 }) == [ ["two", 2], ["one", 1], ["three", 3] ] |
range | Array of the given range | to_a([1..3]) == [1, 2, 3] |
to_object
Syntax
to_object(@declaration or @collection)
Description
Convert given resource declaration or resource collection into a JSON object. Especially useful to convert a declaration into an object, manipulate that object and assign it back to a declaration so that e.g. provision()
may be called on it.
Type | Result | Example |
---|---|---|
collection or declaration | JSON object containing declaration or collection fields. Note that objects created from declarations may be assigned back to a reference | $data = to_object(@servers) |
to_json
Syntax
to_json($value)
Description
Convert a value into a JSON string.
Type | Result | Example |
---|---|---|
any | JSON string | to_json({ "one": 1, "two": 2, "three": 3 }) == '{"one":1,"two":2,"three":3}' |
from_json
Syntax
from_json($value)
Description
Convert a string value into a RCL value.
Type | Result | Example |
---|---|---|
string | RCL value | from_json('{"one":1,"two":2,"three":3}') == { "one": 1, "two": 2, "three": 3 } |
strftime
Syntax
strftime($date, $format_string)
Description
Converts the given datetime to a string using the format/directives provided.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | datetime value | yes | none | |
2 | string value | yes | none | Use any of the directives specified below when creating the string |
The directive consists of a percent (%) character, zero or more flags, optional minimum field width, and a conversion specifier as follows:
%<flags><width><conversion>
Flags:
-
don't pad a numerical output_
use spaces for padding0
use zeros for padding^
upcase the result string#
change case
The minimum field width specifies the minimum width.
Format directives:
Date (Year, Month, Day)
Directive | Description |
---|---|
%Y |
Year with century if provided, will pad result at least 4 digits. -0001 , 0000 , 1995 , 2009 , 14292 , etc. |
%C |
year / 100 (rounded down such as 20 in 2009 ) |
%y |
year % 100 (00..99) |
%m |
Month of the year, zero-padded (01..12) |
%_m |
blank-padded ( 1..12) |
%-m |
no-padded (1..12) |
%B |
The full month name (January ) |
%^B |
uppercased (JANUARY ) |
%b |
The abbreviated month name (Jan ) |
%^b |
uppercased (JAN ) |
%h |
Equivalent to %b |
%d |
Day of the month, zero-padded (01..31) |
%-d |
no-padded (1..31) |
%e |
Day of the month, blank-padded ( 1..31) |
%j |
Day of the year (001..366) |
Time (Hour, Minute, Second, Subsecond)
Directive | Description |
---|---|
%H |
Hour of the day, 24-hour clock, zero-padded (00..23) |
%k |
Hour of the day, 24-hour clock, blank-padded ( 0..23) |
%I |
Hour of the day, 12-hour clock, zero-padded (01..12) |
%l |
Hour of the day, 12-hour clock, blank-padded ( 1..12) |
%P |
Meridian indicator, lowercase (am or pm ) |
%p |
Meridian indicator, uppercase (AM or PM ) |
%M |
Minute of the hour (00..59) |
%S |
Second of the minute (00..60) |
%L |
Millisecond of the second (000..999). The digits under millisecond are truncated to not produce 1000 . |
%N |
Fractional seconds digits, default is 9 digits (nanosecond) |
%3N |
millisecond (3 digits) |
%6N |
microsecond (6 digits) |
%9N |
nanosecond (9 digits) |
%12N |
picosecond (12 digits) |
%15N |
femtosecond (15 digits) |
%18N |
attosecond (18 digits) |
%21N |
zeptosecond (21 digits) |
%24N |
yoctosecond (24 digits). The digits under the specified length are truncated to avoid carry up. |
Weekday
Directive | Description |
---|---|
%A |
The full weekday name (Sunday ) |
%^A |
uppercased (SUNDAY ) |
%a |
The abbreviated name (Sun ) |
%^a |
uppercased (SUN ) |
%u |
Day of the week (Monday is 1, 1..7) |
%w |
Day of the week (Sunday is 0, 0..6) |
ISO 8601 week-based year and week number
The first week of YYYY starts with a Monday and includes YYYY-01-04. The days in the year before the first week are in the last week of the previous year.
Directive | Description |
---|---|
%G |
The week-based year |
%g |
The last 2 digits of the week-based year (00..99) |
%V |
Week number of the week-based year (01..53) |
Week number
The first week of YYYY that starts with a Sunday or Monday (according to %U
or %W
). The days in the year before the first week are in week 0.
Directive | Description |
---|---|
%U |
Week number of the year. The week starts with Sunday. (00..53) |
%W |
Week number of the year. The week starts with Monday. (00..53) |
Seconds since the Epoch
Directive | Description |
---|---|
%s |
Number of seconds since 1970-01-01 00:00:00 UTC. |
Literal string
Directive | Description |
---|---|
%n |
Newline character (\n ) |
%t |
Tab character (\t ) |
%% |
Literal % character |
Combination
Directive | Description |
---|---|
%c |
date and time (%a %b %e %T %Y ) |
%D |
Date (%m/%d/%y ) |
%F |
The ISO 8601 date format (%Y-%m-%d ) |
%v |
VMS date (%e-%^b-%4Y ) |
%x |
Same as %D |
%X |
Same as %T |
%r |
12-hour time (%I:%M:%S %p ) |
%R |
24-hour time (%H:%M ) |
%T |
24-hour time (%H:%M:%S ) |
Example
# Format the current date for CM API 1.5
$time = now()
$api_time = strftime($time, "%Y/%m/%d %H:%M:%S +0000")
Process Information
task_name
Syntax
task_name()
Description
Returns the global name of the current task. See Cloud Workflow Processes for information on tasks.
Arguments
None.
Result
A string that represents the global name of the current task.
Examples
concurrent do
sub task_name: "launch_app" do
@servers = rs.tags.by_tag(resource_type: "servers", tags: ["app:name=foo" ])
@arrays = rs.tags.by_tag(resource_type: "server_arrays", tags: [ "app:name=foo" ])
concurrent do
sub task_name: "launch_servers" do
@servers.launch()
$name = task_name() # $name == "launch_app/launch_servers"
end
sub task_name: "launch_arrays" do
@arrays.launch()
$name = task_name() # $name == "launch_app/launch_arrays"
end
end
end
sub task_name: "notify" do
# ... do things
end
end
tasks
Syntax
tasks()
Description
Arguments
None
Result
Returns a hash of task status keyed by global task name. Valid values for a task status are: completed
, aborted
, canceled
, paused
, or running
.
task_label
Syntax
task_label($label)
Description
Sets the label of the current task. This label is displayed in the Self-Service UI to End Users when an operation is running.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string | yes | none |
Result
The new label string.
task_status
Syntax
task_status($task_name)
Description
Returns the status of the given task. The task name can be relative or absolute (relative match is tried first then absolute if there is no task with a relative name matching the argument).
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | strings | yes | none | Name of task whose status should be returned |
Result
completed
, aborted
, canceled
, paused
or running
. Returns null
for non-existent tasks.
Data Introspection
type
Syntax
type(object)
Description
Returns the name of the type of the given argument. This function is mainly meant to help developing and debugging processes. If the object is a value then the possible type names are: string
, number
, boolean
, datetime
, null
, array
or hash
. If the object is a resource collection then the returned name consist of <namespace>.<resource type>
. If the object is a declaration, then function will return declaration
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or value or declaration | yes | none | Object for which type should be retrieved |
Result
A string representation of the object type.
Examples
@servers = rs.deployments.get(filter: "name==default").servers()
$type_name = type(@servers) # rs.servers
inspect
Syntax
inspect(object)
Description
The inspect()
function returns a human readable representation of the object given as argument. This function is meant as a debugging aid.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource collection or value | yes | none |
Result
String representation of the given object.
Examples
@servers = rs.deployments.get(filter: "name==default").servers()
log_info(inspect(@servers))
String Manipulation
capitalize
Syntax
capitalize($string)
Description
Returns a string with first letter of string
capitalized (if it is the first character) and the rest lower-case.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = "hello"
capitalize($string) == "Hello"
$string = "HeLlO"
capitalize($string) == "Hello"
downcase
Syntax
downcase($string)
Description
Returns a string with all ASCII letters in string
changed to lower-case.
See also: capitalize, upcase
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = "HELLO"
downcase($string) == "hello"
$string = "HeLlO"
downcase($string) == "hello"
gsub
Syntax
gsub($string, $pattern, $replace)
See also: sub
Description
Returns a string with the all occurrences of pattern
substituted for the replace
argument. The pattern is typically a regular expression, but can be a string.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value or regex | yes | none | |
3 | string value | yes | none |
Result
String.
Examples
$string = "hello there howard"
gsub($string, "howard", "tom") == "hello there tom"
gsub($string, /e./, "!") == "h!lo th!!howard"
include?
Syntax
include?($string, $other_str)
Description
Returns true if string
contains other_str
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value | yes | none |
Result
Boolean.
Examples
$string = "hello"
include?($string, "el") == true
include?($string, "yo") == false
index
Syntax
index($string, $substr[, $offset])
Description
Returns the index of the first occurrence of substr
in string
. Returns null
if not found. If the offset
parameter is present, it specifies the position in string
to begin the search (can be a negative number which will be relative to the end of the string).
See also: rindex
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value or regex | yes | none | |
3 | number | no | 0 |
Result
Number or null.
Examples
$string = "hello 123"
index($string, "he") == 0
index($string, "he", 2) == null
index($string, "23") == 7
index($string, /[1-9]/) == 6
insert
Syntax
insert($string, $index, $insertion_string)
Description
Returns a string with insertion_string
inserted before the character at the given index
of string
. Negative indices count from the end of string
, and insert after the given character. If a positive index
is given past the end of string
, insertion_string
will be inserted at the end. If a negative index
is given past the beginning of string
, insertion_string
will be inserted at the beginning.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | number | yes | none | The position at which to insert the new string |
3 | string value | yes | none | The string value to insert |
Result
String.
Examples
$string = "hello"
insert($string, 0, "oh ") == "oh hello"
insert($string, -1, " there") == "hello there"
insert($string, 4, "llooo") == "helllloooo"
join
Syntax
join($array[, $separator])
Description
Join elements of array into a single string using given separator if any.
See also: split
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value | no | "" | Empty string by default |
Result
String.
Examples
$values = ["some", "dash", "delimited", "string"]
join($values, "-") == "some-dash-delimited-string"
join($values) == "somedashdelimitedstring"
lines
Syntax
lines($string[, $separator])
Description
Returns an array of lines in string
split using the supplied separator
($/ by default).
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value | no | $/ |
Result
Array
Examples
$string = "hello\nthere"
lines($string) == ["hello\n","there"]
lines($string, "e") == ["he", "llo\nthe", "re"]
ljust
Syntax
ljust($string, $padded_length[, $padding_value])
See also: rjust
Description
If padded_length
is greater than the length of string
, returns a string of length padded_length
with string
left justified and padded with padding_value
; otherwise, returns string
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | number | yes | none | |
3 | string value | no | " " |
Result
String.
Examples
$string = "hello"
ljust($string, 10) == "hello "
ljust($string, 3) == "hello"
ljust($string, "10", "end") == "helloenden"
lstrip
Syntax
lstrip($string)
Description
Returns a string with leading whitespace removed from string
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = " hello"
lstrip($string) == "hello"
pluralize
Syntax
pluralize($string)
Description
Returns the plural form of the word in the string. Currently only supports the English locale.
See also: singularize
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$singular_type = "cloud"
pluralize($singular_type) == "clouds"
pluralize("ip_address") == "ip_addresses"
reverse
Syntax
reverse($string)
Description
Returns a string with the characters from string
in reverse order.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = "hello"
reverse($string) == "olleh"
rindex
Syntax
rindex($string, $substr[, $offset])
Description
Returns the index of the last occurrence of substr
in string
. Returns null
if not found. If the offset
parameter is present, it specifies the position in string
to end the search — characters beyond this point will not be considered (can be a negative number which will be relative to the end of the string).
See also: index
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value or regex | yes | none | |
3 | number | no | none |
Result
Number or null.
Examples
$string = "hello 123 123"
rindex($string, "3") == 12
rindex($string, "3", 11) == 8
rindex($string, /1./) == 10
rindex($string, "4") == null
rjust
Syntax
rjust($string, $padded_length[, $padding_value])
Description
If padded_length
is greater than the length of string
, returns a string of length padded_length
with string
right justified and padded with padding_value
; otherwise, returns string
.
See also: ljust
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | number | yes | none | |
3 | string value | no | " " |
Result
String.
Examples
$string = "hello"
rjust($string, 10) == " hello"
rjust($string, 3) == "hello"
rjust($string, "10", "end") == "endenhello"
rstrip
Syntax
rstrip($string)
Description
Returns a string with trailing whitespace removed from string
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = "hello "
rstrip($string) == "hello"
singularize
Syntax
singularize($string)
Description
The reverse of pluralize, returns the singular form of a word in a string. Currently only supports the English locale.
See also: pluralize
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$plural_type = "clouds"
singularize($plural_type) == "cloud"
singularize("ip_addresses") == "ip_address"
split
Syntax
split($string, $separator_or_regexp)
Description
Split given string around matches of the given separator or regular expression.
See also: join
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | String value | yes | none | |
2 | String value or regex | yes | none |
Result
Array of strings.
Examples
$text = "some-dash-delimited--string--"
$values = split($text, "/-+/") # ["some", "dash", "delimited", "string"]
strip
Syntax
strip($string)
Description
Returns a string with leading and trailing whitespace removed from string
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = " hello "
lstrip($string) == "hello"
sub
Syntax
sub($string, $pattern, $replace)
Description
Returns a string with the first occurrences of pattern
substituted for the replace
argument. The pattern is typically a regular expression, but can be a string.
See also: gsub
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none | |
2 | string value or regex | yes | none | |
3 | string value | yes | none |
Result
String.
Examples
$string = "hello there howard"
sub($string, "howard", "tom") == "hello there tom"
sub($string, /e./, "!") == "h!lo there howard"
upcase
Syntax
upcase($string)
Description
Returns a string with all ASCII letters in string
converted to upper-case.
See also: capitalize, downcase
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string value | yes | none |
Result
String.
Examples
$string = "hello"
upcase($string) == "HELLO"
$string = "HeLlO"
upcase($string) == "HELLO"
HTTP-HTTPS Functions
This set of functions provides the ability to call HTTP/HTTPS endpoints from within Cloud Workflow. There is one function for each of the well-known HTTP verbs (get
, post
, head
, put
, patch
, delete
, options
, and trace
). The functions take all request attributes as parameters and return the response in a hash value with the keys code
, headers
, cookies
, and body
(each containing their respective response attributes).
There is also a generic function called http_request
which takes the verb as a parameter for any type of HTTP/HTTPS call.
General Information
Making Requests
When using these functions, there is some specific behavior that is of interest:
- If a body is given for the request and the corresponding value is not a string then the functions will encode the value in JSON.
- The verb-specific functions take a single
url
argument that includes the scheme, host, href, and query strings. - The generic
http_request
function takes individual arguments (host
,https
,href
,query_strings
) to form the url.
Common Parameters for HTTP-HTTPS functions
The following parameters are available for all verb-specific and generic HTTP functions.
Name | Possible Values | Required | Description | Example | Default |
---|---|---|---|---|---|
headers | hash of string -> string values | no | HTTP request headers, the keys are the classical content-type (or content_type ), accepts , etc. Passing lowercase with underscore instead of dash is OK, the implementation normalizes to standard HTTP header names behind the scenes. |
{ "X-Api-Version": "1.0" } |
|
body | string (or any value if content-type is JSON) | no | The request body. When unspecified and the method is one of those that expect a body, will default to "" (empty string). A body can be given for methods that don't require it (GET, HEAD) and it will probably get discarded by the server. | ||
raw_response | boolean | no | The default is false . When false (default) and the response is application/json(or an extension of it), the response body will contain the parsed value (not the JSON string). In case of XML content (and unless raw_response is set to true ), the XML is turned into a JSON-compatible data structure (a representation of the XML tree). |
true |
false |
basic_auth | an object with keys username and password |
no | Specifies a pair (username, password) for the basic authentication of this request. | { "username": "foo", "password": "bar" } |
|
cookies | Array of cookie objects | no | An array of cookies to send to the server. Only name and value are allowed. |
[ { "name": "zz", "value": "yy" } ] |
|
noredirect | boolean | no | The default is false . By default the http method will follow any redirection. Infinite loops are detected and raise an error. |
true |
false |
insecure | boolean | no | The default is false . By default the http method will verify SSL certificates. When set to true , the check is not done. |
true |
false |
signature | an object with keys type , access_key , and secret_key |
no | Used for signing requests for AWS. The type should be aws . The access_key and secret_key fields specify the AWS credentials to use for signing the request. If the access_key or secret_key fields are not provided, the default AWS credentials (AWS_ACCESS_KEY_ID or AWS_SECRET_ACCESS_KEY ) for the account will be used. Note: when using the default keys, the user launching the CAT must have adminrole on the account in order to read credential values. |
{ "type": "aws", "access_key": "myaccesskey", "secret_key": "mysecretkey" } |
HTTP-HTTPS Function Responses
The return value of every HTTP/S function is a hash with the following elements:
Name | Type | Description | Example |
---|---|---|---|
code | number | The response code. Eg: 200 | 200 |
headers | hash | The headers from the http response | { "Connection": "keep-alive", "Content-Encoding": "gzip" } |
cookies | array of objects | The cookies received in the response | For a cookie received as string, zz=yy; Domain=.foo.com; path=/; secure, it will be parsed as follows: [ { "name": "zz", "value": "yy", "path": "/", "domain": ".foo.com","expires": <DateTime formatted value>, "secure": true }] |
body | string if raw_response was set to true (or it was set to false but could not be parsed as an object) object if raw_response was set to false (which is by default) and the content type was xml or json |
The body of the response |
http_get, http_post, http_head, http_put, http_patch, http_delete, http_options, http_trace
Syntax
http_get($params), http_post($params), http_head($params), http_put($params), http_patch($params), http_delete($params), http_options($params), http_trace($params)
Description
The verb-specific functions have the following parameters, in addition to the Common Parameters
listed above. The return value from these functions is documented above in HTTP Function Responses
.
Name | Possible Values | Required | Description | Example | Default |
---|---|---|---|---|---|
url | string | yes | The url for the request including the scheme (http/https), host, href, as well as query strings. | https://www.googleapis.com/drive/v2... |
http_request
Syntax
http_request($params)
Description
The general function has the following parameters, in addition to the Common Parameters
listed above. The return value from these functions is documented above in HTTP Function Responses
.
Name | Possible Values | Required | Description | Example | Default |
---|---|---|---|---|---|
verb | string | yes | The HTTP verb (should be one of get, post, patch, put, delete, options, head) | get |
|
host | string | yes | The host of the external service | www.googleapis.com |
|
https | boolean | no | Whether to https/http | true |
false |
href | string | no | The href of the target resource relative to the host. | /drive/v2/files/123 |
"" |
query_strings | hash | no | Query-string values (what comes after a ?in the URL). Keys must be strings. Values are turned into strings (arrays and hashes are JSON encoded). All the values are escaped. |
{ "updateViewedDate": true } |
{} |
Miscellaneous
assert
Syntax
assert(expression)
Description
This function evaluates an assertion. It takes an expression that resolves to a value as an argument. If the expression does not resolve to a value, resolves to null
, or resolves to false
then an error is raised. In all other cases it does nothing.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | expression | yes | none | The expression that should return a value to assert |
Result
None.
now
Syntax
now()
Description
Returns the current time in a datetime value.
Arguments
None
Result
Date time value that represents the current time in UTC.
uuid
Syntax
uuid()
Description
Returns a string containing a Universally Unique IDentifier.
Arguments
None
Result
A string containing a UUID.
sleep
Syntax
sleep($duration)
Description
Makes the current task sleep for the time expressed in duration. A duration consists of numbers suffixed with s (seconds), m (minutes), h (hours) or d (days). Each element of the duration is additive (so 2m30s means 2 minutes plus 30 seconds). If no suffix is specified then the number represents seconds.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | duration | yes | none |
Examples
sleep(60) # sleep one minute
sleep(1h) # sleep 60 minutes
sleep(2m30s) # sleep 150 seconds
Result
None.
sleep_until
Syntax
sleep_until(expression)
Description
This function takes an expression that resolves to a value as argument. If the expression does not resolve to a value, then an error is raised. Sleeps until the expression evaluates to a value that is neither null
nor false
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | expression | yes | none | The expression that should return a value that is neither null nor false for the wait to stop |
Result
None.
sleep_while
Syntax
sleep_while(expression)
Description
This function takes an expression that resolves to a value as argument. If the expression does not resolve to a value then an error is raised. Sleeps while the expression evaluates to a value that is neither null
nor false
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | expression | yes | none | the expression that is run |
Result
None.
keys
Syntax
keys($hash)
Description
Return an array made of all the keys of the provided hash.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | hash | yes | none | Hash for which keys should be retrieved |
Result
Array of strings representing all the keys of the provided hash.
values
Syntax
values($hash)
Description
Return an array made of all the values of the provided hash.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | hash | yes | none | Hash for which values should be retrieved |
Result
Array of strings representing all the values of the provided hash.
map
Syntax
map($mapping_name, $key_name, $value_name)
Description
Return the value of a two level hash given a key and value name. This function is syntactic sugar around the [] operator. It may provide a better notation when writing declarative code (e.g. in resource declarations). So doing map($hash, $key, $value)
is equivalent to $hash[$key][$value]
.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | hash | yes | none | Hash for which value should be retrieved |
2 | string | yes | none | Name of key |
3 | string | yes | none | Name of value |
Result
Hash value at given key and value name.
xpath
Syntax
xpath($xml_string, $xpath)
Description
Using a XPath string, extracts information out of an XML string.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | string | yes | none | XML string |
2 | string | yes | none | XPath string like //item[2]/name/text()or css:div.lipath |
The xpath argument can be passed a css:
prefix, in which case the path is a CSS path, not a XPath.
Result
Array of [XML] strings.
tag_value
Syntax
tag_value(@resource, $tag_prefix)
Description
Returns the value
part of a machine tag given the <namespace>:<predicate>
of the tag.
Arguments
Position | Possible Values | Required | Default Value | Comment |
---|---|---|---|---|
1 | resource | yes | none | |
2 | string | yes | none | <namespace>:<predicate> to find |
Result
String containing the value
part of the tag, if it is found. Otherwise, null