The aim of this package is to aid you in crawling OJS archives, issues, articles, galleys, and search results, and retrieving/scraping metadata from articles. ojsr functions rely on OJS routing conventions to compose the URL for different scraping scenarios.
From CRAN:
install.packages('ojsr')
From Github:
install.packages('devtools')
::install_github("gastonbecerra/ojsr") devtools
get_issues_from_archive()
: scrapes
issues URLs from OJS issues archiveget_articles_from_issue()
: scrapes
articles URLs from the ToC of OJS issuesget_articles_from_search()
: scrapes
OJS search results for a given criteria to retrieve articles URLsget_galleys_from_article()
: scrapes
galleys URLs from OJS articlesget_html_meta_from_article()
: scrapes
metadata from OJS articles HTMLget_oai_meta_from_article()
: retrieves
OAI records for OJS articlesparse_base_url()
: parses URLs against
OJS routing conventions to retrieve the base URLparse_oai_url()
: parses URLs against
OJS routing conventions to retrieve the OAI protocol URLLet’s say we want to collect metadata from some journals to compare their top keywords. We have the journals’ names and URLs, and can use ojsr to scrap their issues, articles and metadata.
library(dplyr)
library(ojsr)
journals <- data.frame ( cbind(
name = c( "Revista Evaluar", "PSocial" ),
url = c( "https://revistas.unc.edu.ar/index.php/revaluar", "https://publicaciones.sociales.uba.ar/index.php/psicologiasocial")
), stringsAsFactors = FALSE )
# we are using the journal URL as input to retrieve the issues
issues <- ojsr::get_issues_from_archive(input_url = journals$url)
# we are using the issues URL we just scraped as an input to retrieve the articles
articles <- ojsr::get_articles_from_issue(input_url = issues$output_url)
# we are using the articles URL we just scraped as an input to retrieve the metadata
metadata <- ojsr::get_html_meta_from_article(input_url = articles$output_url)
# let's parse the base URLs from journals and metadata, so we can bind by journal
journals$base_url <- ojsr::parse_base_url(journals$url)
metadata$base_url <- ojsr::parse_base_url(metadata$input_url)
metadata %>% filter(meta_data_name=="citation_keywords") %>% # filtering only keywords
left_join(journals) %>% # include journal names
group_by(base_url, keyword = meta_data_content) %>% tally(sort=TRUE)