Wrangler Operating System

Wrangler is an operating system written in KRL for picos. Wrangler provides developers a way to programmatically and easily manage picos.

To use Wrangler as a module, add "use module io.picolabs.wrangler alias wrangler" in your meta block.

Functions

For all functions, enter the parameters in the order listed.

children

Returns an array of the children of the pico. Has optional parameter "name" which returns just the attributes for the child with the specific name if it exists, otherwise it returns attributes on every child if not provided. It gives attributes:

parent_eci: The ECI from the picoto the respective child

name: The child pico's name

id: The id of the child pico

eci: The main wrangler ECI for the child pico

children = wrangler:children()
/*
[
  {
    "parent_eci": "CyrmdG4PkiVYRUo2K69k2E",
    "name": "Section CS462-1 Pico",
    "id": "cjh6pbzun005zvde06bwy2pci",
    "eci": "JfcEBxEK5WDKA69Bvach4Y"
  },
  {
    "parent_eci": "Tg5ULPBYByJjsEoKpfsbQ2",
    "name": "Section CS462-2 Pico",
    "id": "cjh6pc28r0067vde04qd23t6o",
    "eci": "56S414r4Uq4kGx6Xi1qmSs"
  }
]
*/

myself

Returns a map giving basic meta information about the pico. This information includes the pico's ID, ECI, and name.

id: The ID of the pico

eci: The main wrangler ECI of the pico

name: The name of the pico

myself_result = wrangler:myself()
/*
{
  "id": "cjhtji2op009hpkrq35bcpodh",
  "eci": "4bUS9W4HY5S1YfsAM9Ygw5",
  "name": "Front Porch"
}
*/

skyQuery

A user friendly way to make an HTTP request between picos. It provides cleanup and returns the error if the returned HTTP status was not 200.

It is mainly used to programmatically call functions inside of other picos from inside a rule. However, do not have a pico query itself, or have two picos query each other simultaneously. See Accessing a Function Shared by Another Pico for more information.

pre {
	eci = event:attr("eci")
	wellknown = wrangler:skyQuery( eci , "io.picolabs.subscription", "wellKnown_Rx")
}
if wellknown{"error"}.isnull() then
	noop()
always {
	ent:savedWellknown := wellknown;
}
/*
Query the the function wellKnown_Rx() in the ruleset "io.picolabs.subscription" through the pico ECI given in the event attribute "eci".
*/

pre {
  eci = eci_to_other_pico;
  args = {"arg1": val1, "arg2": val2};
  answer = Wrangler:skyQuery(eci,"my.ruleset.id","myFunction",args);
}
if answer{"error"}.isnull() then noop();
fired {
  // process using answer
}

Defactions

Events/Rules

When a rule raises an event in the postlude, it will also pass along all the attributes it received (including any attributes not used in that event) in addition to any new information that may be relevant to other rules.

Bolded attributes are required.

Ruleset Events

installRulesets

(Domain: wrangler, Type: install_rulesets_requested)

Installs the given rulesets in the pico that receives this event.

eventAttrs:

Directives Returned:

send_directive("rulesets installed", { "rids": /* An array of rids that were installed*/ });

Raised Events:

{
"rids": /* An array of rids that were installed*/
}

Sent Events:

None

Pico Events

createChild

(Domain: wrangler, Type: child_creation or new_child_request)

Creates a new child for this pico with optional arguments for the child's name, and rulesets to install on it upon creation.