How can I POST a simple HTML form in R?

Question

I\'m relatively new to R programming and I\'m trying to put some of the stuff I\'m learning in the Johns Hopkins Data Science track to practical use. Specifically, I would

Answer 1

I know this is an old question, but adding the

style='POST'

parameter to postForm does the trick as well.

Answer 2

Well, it appears to work with the httr library.

library(httr)

url <- "https://www.treasurydirect.gov/GA-FI/FedInvest/selectSecurityPriceDate.htm"

fd <- list(
    submit = "Show Prices",
    priceDate.year  = 2014,
    priceDate.month = 12,
    priceDate.day   = 15
)

resp<-POST(url, body=fd, encode="form")
content(resp)

The rvest library is really just a wrapper to httr. It looks like it doesn't do a good job of interpreting absolute URLs without the server name. So if you look at

f1$url
# [1] /GA-FI/FedInvest/selectSecurityPriceDate.htm

you see that it just has the path and not the server name. This appears to be confusing httr. If you do

f1 <- set_values(f0[[2]], priceDate.year=2014, priceDate.month=12, priceDate.day=15)
f1$url <- url
test <- submit_form(s, f1)

that seems to work. Perhaps it's a big that should be reported to rvest. (Tested on rvest_0.1.0)