Lift and Escalator API: Difference between revisions

Revision as of 14:24, 8 September 2023

Network Rail's Lift and Escalator API contains details of the status of lifts and escalators at many locations in Great Britain. The official documentation is quite sparse, hence this article was created by Peter in order to document the API unofficially.

Signing up

Authentication isn't necessary for V1 GraphQL functionality that has been migrated to V2, however it is probably worth your while to show how many people are using the API. Authentication is necessary for the V2 REST endpoints, and allows slightly deeper GraphQL queries.

Register for an account on the Lift and Escalator API portal. Once you've verified your email address, you can navigate to the "products" tab. Click on "Developer" in the list on this page, then create a new subscription with a name of your choosing. Now, navigate to "Profile", you should be able to see your keys.

Access

Despite the wording of the supplied documentation, it's not necessary to exchange your subscription key for an API key for REST requests, you can simply pass the subscription key in the x-lne-api-key HTTP header.

The GraphQL endpoint does not necessarily require authentication, as outlined in the above section.

Data elements (V1)

The following data elements are held within the API:

Field	Description
uprn	Unique asset identifier (not a UPRN)
sensorId	A four-digit sensor identifier for the Electronic Monitoring Unit (EMU), left-padded with zeroes if required.
blockId	An identifier for the location of the asset within a station
blockTitle	The name of the location within the station
station	Name of the station at which this asset is located
location	Name of the location within the station at which this asset is located
lat	Latitude in (WGS84)
long	Longitude (WGS84)
postcode	Postcode of the station in which this asset is located
route	Network Rail Route in which this asset is located
territory	Network Rail Region in which this asset is located
toc	Set to 'Managed Stations' for Network Rail Managed Stations, otherwise the name of the train operator
branch	Unknown, but possibly the branch of the lift or escalator maintainer's organisation where
type	Type of asset, e.g. Lift or Escalator
status	Current status of the asset
isolated	Indicates whether the asset is powered down or disconnected
engineerOnSite	Indicates if an engineer has logged in to the sensor and is servicing the asset
independant	(note the misspelling) Indicates if the lift is on Independent Service by use of a car preference key
updatedTime	Date and time when the status was last updated

Data elements (V2)

Asset

Field	Description
id	Unique identifier (of asset?)
description	e.g. "Colonnade Lift", "Lift 3,Platform 20"
displayName	e.g. "Lift to Colonnade ", "Lift, Platform 20"
sensorId	A four-digit sensor identifier for the Electronic Monitoring Unit (EMU), left-padded with zeroes if required.
blockId	An identifier for the location of the asset within a station
crs	CRS code of the station at which this asset is located
location	Name of the location within the station at which this asset is located (e.g. "Colonnade Lift", "Platform 20")
type	Type of asset, e.g. Lift or Escalator
status	(Relation) Current status of the asset

Status

Field	Description
sensorId	ID of sensor
isolated	Indicates whether the asset is powered down or disconnected
engineerOnSite	Indicates if an engineer has logged in to the sensor and is servicing the asset
independent	(note that this is now not misspelled), indicates if the lift is in independent service mode.
asset	(Relation) Asset to which this status relates

Making a GraphQL request

All requests are through the API endpoint (https://nr-lift-and-escalator.azure-api.net/graphql/v2). Requests must be made via an HTTP POST request, navigating to this URL in a web browser will make an HTTP GET request, which will result in the following error:

{"path":"$","error":"resource does not exist","code":"not-found"}

The API uses GraphQL, which allows complex queries to be submitted in an HTTP POST request. A query is just a JSON data structure with some fields to filter on, and other fields to return.

Simple requests

All assets at a station (V1)

To return the status of all lifts and escalators at a particular station, such as Edinburgh Waverley:

query MyQuery {
  status(where: {station: {_eq: "Edinburgh Waverley"}}) {
    blockTitle
    branch
    engineerOnSite
    independant
    isolated
    lat
    location
    long
    postCode
    route
    sensorId
    station
    status
    territory
    toc
    type
    updatedTime
    uprn
    blockId
  }
}

All assets at all stations (V2)

query {
	assets {
		blockId
		crs
		description
		displayName
		id
		location
		sensorId
		status {
			engineerOnSite
			independent
			isolated
			sensorId
			status
		}
		type
	}
}

Stream of updates

It is supposedly possible to make an API request and receive a stream of updates using the @live directive on the GraphQL query, but does not seem to work on this API.

Room for improvement

There is some room for improvement on the API:

Null entries - some fields are set to "#N/A", and some are set to null
Unmapped sensors - there are instances (such as sensorId 3104) where no data has been filled in about the asset at all
No escalators - some escalators are included but fall fully within the problem above, all have null locational data
Incorrect references to territories - the term 'territory' was in use during Railtrack days, but is no longer used - Region and Routes are the current terminology
Out-of-date TOC information - sensor 4052 refers to London Midland, sensor 3082 refers to East Coast, and 6148 to Arriva Trains Wales - none of whom currently operate franchises
Lack of machine-interpretable data - sensor 5006 is described as 'Wolverhampton Stn Lift/Escalator 05', in location 'Passenger Lift Platform 4', whereas sensor 8127, 'Imperial Wharf Stn Lift/Escalator 01' is in location 'Platform 1' - these are not easy to parse and necessarily link to a particular platform
Non-passenger assets - 1032 and 4034 are lifts situated in the South Wales and Thames Valley signalling centres, respectively. 1041 is "Mepham Street Goods No. 2" at London Waterloo, and 5054 will take you to "Red Star Parcels" in Milton Keynes

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 == Data elements (V2) ==
 === Asset ===
-Fields
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