Rvest scraping google news with different number of rows

Question

I am using Rvest to scrape google news.
However, I encounter missing values in element "Time" from time to time on different keywords. Since the values are missing, it will end up having "different number of rows error" for the data frame of scraping result.
Is there anyway to fill-in NA for these missing values?

Below is the example of the code I am using.

html_dat <- read_html(paste0("https://news.google.com/search?q=",Search,"&hl=en-US&gl=US&ceid=US%3Aen"))

  dat <- data.frame(Link = html_dat %>%
                  html_nodes('.VDXfz') %>% 
                  html_attr('href')) %>% 
  mutate(Link = gsub("./articles/","https://news.google.com/articles/",Link))

  news_dat <- data.frame(
   Title = html_dat %>%
   html_nodes('.DY5T1d') %>% 
   html_text(),
   Link = dat$Link,
   Description =  html_dat %>%
   html_nodes('.Rai5ob') %>% 
   html_text(),
   Time =  html_dat %>%
   html_nodes('.WW6dff') %>%
   html_text() 
 )    

Answer 1

Without knowing the exact page you were looking at I tried the first Google news page.

In the Rvest page, html_node (without the s) will always return a value even it is NA. Therefore in order to keep the vectors the same length, one needed to find the common parent node for all of the desired data nodes. Then parse the desired information from each one of those nodes.

Assuming the Title node is most complete, go up 1 level with xml_parent() and attempt to retrieving the same number of description nodes, this didn't work. Then tried 2 levels up using xml_parent() %>% xml_parent(), this seems to work.

library(rvest)

url <-"https://news.google.com/topstories?hl=en-US&gl=US&ceid=US:en"
html_dat <- read_html(url)

Title = html_dat %>%  html_nodes('.DY5T1d') %>%   html_text()

# Link = dat$Link
Link = html_dat %>%  html_nodes('.VDXfz') %>%   html_attr('href') 
Link <-  gsub("./articles/", "https://news.google.com/articles/",Link)

#Find the common parent node 
#(this was trial and error) Tried the parent then the grandparent
Titlenodes <- html_dat %>%  html_nodes('.DY5T1d') %>% xml_parent()  %>% xml_parent() 
Description =  Titlenodes %>%  html_node('.Rai5ob') %>%  html_text()
Time =  Titlenodes %>%  html_node('.WW6dff') %>%   html_text() 
 
answer <- data.frame(Title, Time, Description, Link)