R script to query UK Gov petitions and extract NI data

plot_ni_parliamentaries.R

library(httr)
library(magrittr)
library(jsonlite)


# The `constituencies.data` endpoint does not provide the 'party' element for some reason now!
# Here is a manual mapping of constitency to party
PARTY_CONSTITUENCY = list(
  "Belfast East" = "Democratic Unionist Party",
  "Belfast North" = "Democratic Unionist Party",
  "Belfast South" = "Democratic Unionist Party",
  "Belfast West" = "Sinn Fein",
  "East Antrim" = "Democratic Unionist Party",
  "East Londonderry" = "Democratic Unionist Party",
  "Fermanagh and South Tyrone" = "Sinn Fein",
  "Foyle" = "Sinn Fein",
  "Lagan Valley" = "Democratic Unionist Party",
  "Mid Ulster" = "Sinn Fein",
  "Newry and Armagh" = "Sinn Fein",
  "North Antrim" = "Democratic Unionist Party",
  "North Down" = "Independent",
  "South Antrim" = "Democratic Unionist Party",
  "South Down" = "Sinn Fein",
  "Strangford" = "Democratic Unionist Party",
  "Upper Bann" = "Democratic Unionist Party",
  "West Tyrone" = "Sinn Fein")


petition.data <- "https://petition.parliament.uk/petitions/241584.json" %>%
  httr::GET() %>%
  httr::content(as = "text") %>%
  jsonlite::fromJSON()

signituresByConstituency <- petition.data[["data"]][["attributes"]][["signatures_by_constituency"]]

constituencies.data <- "https://petition.parliament.uk/constituencies.json" %>%
  httr::GET() %>%
  httr::content(as = "text") %>%
  jsonlite::fromJSON()

population.data <- "https://petitionmap.unboxedconsulting.com/json/mps/population_ons.json" %>%
  httr::GET() %>%
  httr::content(as = "text") %>%
  jsonlite::fromJSON()

ni.constituencies.data <- list()
for (i in 1:(signituresByConstituency %>% nrow())) {
  id <- signituresByConstituency$ons_code[i]
  constituencies.data[[id]]$signature_count <- signituresByConstituency$signature_count[i]
  constituencies.data[[id]]$population <- population.data[[id]]$population
  constituencies.data[[id]]$proportion <- (signituresByConstituency$signature_count[i]/population.data[[id]]$population) * 100
  if (substr(id, 1, 1) == "N") {
    ni.constituencies.data[[id]] <- constituencies.data[[id]]
  }
}

population <- proportion <- signature_count <- 
  ons_code <- constituency <- party <- mp <- c()
for (i in 1:(ni.constituencies.data %>% length())) {
  proportion %<>% append(ni.constituencies.data[[i]]$proportion)
  population %<>% append(ni.constituencies.data[[i]]$population)
  signature_count %<>% append(ni.constituencies.data[[i]]$signature_count)
  ons_code %<>% append(ni.constituencies.data[[i]]$ons_code)
  constituency %<>% append(ni.constituencies.data[[i]]$constituency)
  party %<>% append(PARTY_CONSTITUENCY[ni.constituencies.data[[i]]$constituency][[1]])
  mp %<>% append(ni.constituencies.data[[i]]$mp)
}

df <- data.frame(
  population = population,
  proportion = proportion,
  signature_count = signature_count,
  ons_code = ons_code,
  constituency = constituency,
  party = party,
  mp = mp,
  stringsAsFactors = FALSE)

totalNICount <- sum(df$signature_count)
totalPetitionCount <- petition.data[["data"]][["attributes"]][["signature_count"]]

df <- df[order(-proportion), ][1:10, ]
df$constituency <- factor(df$constituency, levels = df$constituency)

setColours <- setNames(
  c("#D32F2F", "#BDBDBD", "#43A047"), 
  sort(unique(df$party)))

df %>%
  ggplot() +
  geom_bar(
    mapping = aes(
      y = proportion, 
      x = constituency, 
      fill = party), 
    stat = "identity") + 
  scale_fill_manual(values = setColours) +
  labs(title = "NI constituencies voting to Revoke") +
  ylab("Proportion of constituents (%)") +
  xlab("") +
  theme_minimal() +
  theme(
    legend.position = "bottom", 
    legend.title = element_blank(), 
    axis.text.x = element_text(
      angle = 90, 
      hjust = 1))