narrowbotR

narrowbotR (pronounced "narrow-boater") is a Mastodon bot written in R that publishes information about the UK canal network. This bot is inspired by Matt Dray's londonmapbot which randomly posts a location in the rough vicinity of London every 30 minutes. This bot seeks to do something similar: posting a random location on the UK canal network at a regular interval. It is a work in progress. At present it only publishes information about the English and Welsh canal network.

The bot also used to run on Twitter, but as of 15 April 2023 I have decommissioned the Twitter bot due to changes in Twitter's Terms of Service.

The bot works as follows:

• The data from Canal and River Trust's open data feeds has been downloaded and aggregated into a single file, only the point-based data at this stage, let's call each item in this data a "feature"
• A feature at random will be selected from the dataset
• A search of publicly available photos on Flickr, licensed for sharing, in the vicinity of the feature's position is made
• The photo metadata is scored and the top-scoring photo selected
• If there are only a small number of photos returned then an aerial photo of the location sourced from Mapbox will be used
• A post is constructed to provide the feature's name, the feature's type, an open-street map link to the location, and citation of the author a link to the Flickr page of the photo if a Flickr photo is being used.
• If the flickr photo has tags then these are re-used to add to the standard hashtags included in the post
• The tweet is then posted using a custom version of the rtoot::post_toot() function that has been extended to embed location data in the tweet's metadata.
• The feature dataset is created only occasionally and stored in data/all_points.RDS for efficiency

You can read a more detailed explanation of how the bot works in this blog post.

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Dev notes

To do:

• Create twitter account
• Get twitter developer credentials
• Investigate CRT open data
• Write database build functions
• Write database maintenance functions
• Build database of CRT data
• Investigate Flickr API for geotagged photos
• Write tweet functions
• Write GitHub automation
• Future: investigate data for Scottish/Irish canals

Need to decide on a maintenance schedule for updating the database

For testing purposes use the following lat/long pairs (these are popular features that should have nearby photos):

• list(long = -2.03219634864333, lat = 51.3520732144106): Lock 29, Devizes Lock (bottom of Caen Hill flight)
• list(long = -1.18474539433226, lat = 52.2845877855651): Braunston Tunnel West Portal
• list(long = -3.08780897790795, lat = 52.9704074998854): Pontcysyllte aqueduct