Web scraping script

README.org

@@ -28,6 +28,7 @@ data using the R programming environment
 ** Web scraping
 
  * [[./script/scraping2.R][Web scraping example]]
+ * [[./script/web_scraping.R][Using 'rvest' for scraping]]
 
 ** Interesting packages
 

script/web_scraping.R

@@ -0,0 +1,71 @@
+#' ---
+#' title: "Web scraping"
+#' date: "2022-06-17"
+#' author: "Jose https://ajuda.multifarm.top"
+#' output:
+#'   html_document:
+#'    code_folding: show
+#'    toc: yes
+#'    toc_float:
+#'      smooth_scroll: true
+#'    df_print: paged
+#'    highlight: zenburn
+#' ---
+
+#' remove objects
+
+rm(list = ls())
+
+#' Libraries
+library(rvest)
+
+#' Data
+
+url <- 'https://www-remessaonline-com-br.cdn.ampproject.org/c/s/www.remessaonline.com.br/blog/agtech/amp/'
+
+#'------------------------------------------------------------------------------
+#'
+#' ## Scraping a url
+#'
+#' ------------------------------------------------------------------------------
+
+### Headings
+
+u <- read_html(url)
+
+class(u)
+
+str(u)
+
+u[[2]]
+
+html_elements(u, "h1")
+
+html_elements(u, "h2")
+
+html_nodes(u, "h3") |> html_text2() |> data.table::data.table()
+
+html_elements(u, "h4")
+
+html_elements(u, "h5")
+
+html_children(u)
+
+nodes <- paste0('h', c(1:6))
+
+?html_elements
+
+### Paragraphs
+
+pel <- html_elements(u, "p") |> html_text()
+
+peli <- as.list(pel)
+
+peli[[2]]
+
+### List elements
+
+html_nodes(u, "ul") |> html_text()
+
+html_nodes(u, "li") |> html_text()
+