Skip to main content

Service control

A service is node-level machinery rather than something the user thinks of as a device, such as time and timezone. ESPRMNeoService and ESPRMNeoServiceParam work almost exactly like their device counterparts, with two differences worth knowing before you use them.

const time = node.services.find((s) => s.name === "Time");
const timezone = time?.params.find((p) => p.id === "TZ");

await timezone?.setValue("Asia/Kolkata");

How services differ from devices​

DeviceService
Reached throughnode.devicesnode.services
Parameter carriesdeviceNameserviceName
Primary parameterprimaryParamnone
Cached readsgetParams({ cache })always live

There is no primaryParam on a service, because a service has no single main control. And service.getParams() takes no options; it is always a live read.

Read service parameters​

const params = await time?.getParams();

getParams() returns Promise<ESPRMNeoServiceParam[]>, the same instances as service.params, with value updated. It fetches over the best available transport every time; there is no cached mode.

It throws if the parent node reference has been garbage-collected. Keep the node alive for as long as you hold a service.

Write a service parameter​

await timezone?.setValue("Asia/Kolkata");

setValue(value) returns Promise<ESPAPIResponse> and behaves exactly as it does on a device parameter, including the caveat that acceptance is not confirmation. See Device control.

You can also address a service through node.setParams(), which takes service names alongside device names in the same payload:

await node.setParams({
  Time: { TZ: "Asia/Kolkata" },
});

Identifying a service by type​

Names are firmware-chosen; types are stable. Match on type when you need a specific service rather than a specific name:

const time = node.services.find((s) => s.type === "esp.service.time");

A service's type comes straight from the node configuration the firmware publishes, so the set available to you depends on what that node runs.