Recursively download data - Tidyverse way

Thinking of trying my hand at participating in this week's #TidyTuesday exercise.

I'll take this in small steps and hopefully get to the end.

Here is an approach to get the data into Rstudio!

setwd("~/Dropbox/pandora/My-Projects/repos/diary/writing/")

# credit: https://github.com/WSJ/measles-data
# [Tom Mock on Twitter: "The @R4DScommunity welcomes you to week 9 of #TidyTuesday! We're exploring Measles vaccination!! 📁 https://t.co/sElb4fcv3u 📰 https://t.co/69BCOyRJm2 #r4ds #tidyverse #rstats #dataviz https://t.co/Klj5yeUm26" / Twitter](https://twitter.com/thomas_mock/status/1232034689281601536)
library(data.table)

# Data for each individual school
url_all <- "https://github.com/WSJ/measles-data/blob/master/all-measles-rates.csv?raw=true"
dt_all <- fread(url_all)

# More generalized data by state counties or state school districts
url_state_overview <- "https://github.com/WSJ/measles-data/raw/master/state-overviews.csv"
dt_state_overview <- fread(url_state_overview)


# Same data as all-measles-rates, but seperated by state
# example here
url_state_arizona <- "https://github.com/WSJ/measles-data/raw/master/individual-states/arizona.csv"
dt_state_arizona <- fread(url_state_arizona)

# need to learn to use tidyverse
library(tidyverse)

df_all <- as_tibble(dt_all)

# get state data as filters on df_all
df_all %>% 
select(state) %>% 
distinct() %>% 
 .$state %>% 
walk(., ~ assign(paste0("df_",tolower(.x)), df_all %>% filter(state==.x), envir=.GlobalEnv))


# lets actually download the state data! ... straight from github
# WSJ provided it in a folder organized by state name
get_state_measles_data <- function(state) {
    tryCatch({
      print(glue("downloading data for ... {state}"))

      # supressing message ... silent .. https://github.com/tidyverse/readr/issues/530
      d <- read_csv(glue("https://github.com/WSJ/measles-data/raw/master/individual-states/{state}.csv"), col_types = cols())
      assign(glue("df_{state}"), d, envir=.GlobalEnv) 
    },
    error = function(error) {
      print(glue("error while downloading data for ... {state}"))
    })
}

# get the states
df_all %>% 
select(state) %>% 
distinct() %>% 
mutate(state = tolower(state)) %>% 
.$state -> states


library(glue)
glue("# of states: {NROW(states)}")

walk(states, get_state_measles_data)

# working with lists in tidy: [jennybc/repurrrsive: Recursive lists to use in teaching and examples, because there is no iris data for lists.](https://github.com/jennybc/repurrrsive)