I am trying to scrape data from an interactive map (looking to get crime data for a county). I am using R (rvest) and trying to use phantomjs too. I'm new to web scraping so I am not really understanding how all the elements work together (trying to get there).
The problem I believe I am having is that after I run the phantomjs and upload the html using R's rvest package, I end up with more scripts and no clear data in the html. My code is below.
writeLines("var url = 'http://www.google.com';
var page = new WebPage();
var fs = require('fs');
page.open(url, function (status) {
just_wait();
});
function just_wait() {
setTimeout(function() {
fs.write('cool.html', page.content, 'w');
phantom.exit();
}, 2500);
}
", con = "scrape.js")
A function that takes in the url that I want to scrape
s_scrape <- function(url = "https://gis.adacounty.id.gov/apps/crimemapper/",
js_path = "scrape.js",
phantompath = "/Users/alihoop/Documents/phantomjs/bin/phantomjs"){
# this section will replace the url in scrape.js to whatever you want
lines <- readLines(js_path)
lines[1] <- paste0("var url ='", url ,"';")
writeLines(lines, js_path)
command = paste(phantompath, js_path, sep = " ")
system(command)
}
Execute the js_scrape() function and get a html file saved as "cool.html"
js_scrape()
Where I am not understanding what to do next is the below R code:
map_data <- read_html('cool.html') %>%
html_nodes('script')
The output I get in the HTML via phantomjs is just scripts again. Looking for help on how to proceed when faced (in my mind) is javascript nested in javascript scripts(?)
Thank you!