Transport for London has temporarily suspended access to London Underground live data feed as a result of overwhelming demand from applications that pull train departure and arrival times from the service, as well as station and line status information.
The feed, which only went live for use by third-party developers on 15 June, saw a huge increase in traffic, jumping from around 180,000 hits per week to more than 10 million, according to Transport for London (TfL). The London Datastore, responsible for handling the API requests from software developers, sent out an alert on its blog on Thursday saying the service had been suspended .
"Owing to overwhelming demand by apps that use the service, the London Underground feed has had to be temporarily suspended. We hope to restore the service as soon as possible, but this may take some days," wrote The London Datastore's Lisa Price.
Access to TfL's London Underground data was opened up on 1 June, with the express aim of allowing developers to independently create mobile apps for commercial purposes. The service was still unavailable on Monday. Despite having had to suspend access to its dataset, TfL is taking the overwhelming demand as a positive sign.
"We are really encouraged that the feed to our Tube departure information is so popular, and TfL is doing everything to restore it as soon as possible, but this may take some time. We're sorry for the temporary disruption to this API Beta feed, and we will provide an update as soon as we have further information", said Steve Townsend, director of information management for London Underground, in a statement on Friday.
The demand for up-to-the-minute London Underground data comes from various mobile apps, which allow users to plan their daily commute down to the second by keeping an eye on a trains' live progress.
Access to the data provides developers with minute-by-minute updates on virtually all trains running on the London Underground network, including live arrival and departure data, as well as station and line updates.
Mobile app developers are not the only ones to be hit by the withdrawal of the data feed. Several websites that use the API to plot live train progress have also been derailed by the decision. The sites affected include Matthew Somerville's live train map for the London Underground, which was one of the first of its kind to go live when the data was publicly released. The site is live, but is showing no train data.
In comments on the London Datastore blog post, developers made suggestions as to how TfL could improve the data service in order to avoid it being overtaken by demand in the future.
"I'm really not surprised if it got overloaded. It seemed to be designed to handle personalised requests, eg from someone occasionally wanting info about a single station, and needing all the textual descriptions each time," wrote commenter Drew.