01_get_2020_block_groups.R

library(tidyverse)
setwd('2020shp/')

get_block_group_shp <- function(fl_name, state_folder, state_fips) {
  fl.name.zip <- paste0(fl_name, '.zip')
  download.file(paste0('https://www2.census.gov/geo/tiger/TIGER2020PL/STATE/', state_folder, "/",
                       state_fips, "/", fl.name.zip),
                destfile=fl.name.zip)
  unzip(fl.name.zip)
  unlink(fl.name.zip)
  fl.name.shp <- paste0(fl_name, '.shp')
  d.tmp <- sf::read_sf(fl.name.shp) %>% sf::st_transform(5072)
  unlink(list.files(pattern = fl_name))
  return(d.tmp)
}

states <-
  tigris::states() %>%
  sf::st_drop_geometry() %>%
  arrange(STATEFP) %>%
  select(STATEFP, NAME) %>%
  mutate(state_folder = paste0(STATEFP, "_", toupper(NAME)),
         state_folder = stringr::str_replace_all(state_folder, " ", "_"),
         fl_name = paste0('tl_2020_', STATEFP, '_bg20')) %>%
  filter(as.numeric(STATEFP) < 57)

block_group_shp <- pmap(list(states$fl_name, states$state_folder, states$STATEFP),
                        possibly(get_block_group_shp, NA_real_))
#block_group_shp[[6]] <- get_block_group_shp(states$fl_name[6], states$state_folder[6], states$STATEFP[6])
names(block_group_shp) <- states$NAME

block_group_shp_all <- block_group_shp[[1]]

for (i in 2:length(block_group_shp)) {
  block_group_shp_all <- rbind(block_group_shp_all, block_group_shp[[i]])
}

blk_grps_sf_2020 <- block_group_shp_all %>%
  dplyr::select(census_block_group_id_2020 = GEOID20,
                geometry) %>%
  mutate(census_block_group_id_2020 = as.character(census_block_group_id_2020))

saveRDS(blk_grps_sf_2020, "block_groups_2020_5072.rds")