// ScrapeArticle fetches and parses the article.
// article should be provided as a *Article.
func ScrapeArticle(article Article) error {
cookies := NewCookieJar()
client := &http.Client{Jar: cookies}
// build request
req, err := http.NewRequest("GET", article.GetLink(), nil) //create http request
err = buildArticleHeader(req)
if err != nil {
log.Error("could not build article request:", err)
return err
}
//send http request
resp, err := client.Do(req)
if err != nil {
log.Error("error sending article request:", err)
return err
}
defer resp.Body.Close()
// TODO: check resp.Header to see if X-Article-Template is [full]
// parse request
parser := html.NewTokenizer(resp.Body)
err = article.DoParse(parser) //parse the html body
if err != nil {
log.Error("error building article request:", err)
return err
}
return nil
}
// UpdateRSS finds articles currently in the RSS feed.
// Clears old articles out of RSS feed before getting new ones.
// rss should be passed as an *RSS
func UpdateRSS(rss RSS) error {
// clear out old articles so we don't double add
rss.GetChannel().ClearArticles()
// send request
resp, err := http.Get(rss.GetLink())
if err != nil {
// TODO: error checking here
log.Error("error getting RSS:", err)
return err
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Error("error reading RSS body:", err)
// TODO: error handling
return err
}
err = xml.Unmarshal(body, rss)
if err != nil {
log.Error("could not build RSS obj from rss request:", err)
return err
}
return nil
}
// Run runs the client in an infinite loop
func (c *Client) Run() {
ticker := time.NewTicker(time.Duration(10) * time.Second)
c.ignoreBad = make(map[string]struct{})
defer c.printBad()
for {
// wait for the next itr
<-ticker.C
// go get the article
req, err := Get(c.IP)
if err != nil {
log.Error(err)
continue // go around to the next iteration
}
// don't reply to empty requests
if netScraper.IsEmptyRequest(req) {
log.Info("got empty request")
continue
}
if _, contains := c.ignoreBad[req.URL]; contains {
log.Warn("got bad article:", req.URL)
continue
}
log.Info("got article", req.URL)
// for now only use the NYT
article := scraper.NYTArticle{}
article.Link = req.URL
err = scraper.ScrapeArticle(&article)
if err != nil {
c.ignoreBad[req.URL] = struct{}{} // add to ignore
log.Error("could not scrape article", req.URL, ":", err)
continue
}
if len(article.GetData()) == 0 {
c.ignoreBad[req.URL] = struct{}{} // add to ignore
log.Error("bad article body for url:", req.URL)
continue
}
// send article back up
result := netScraper.Response{URL: req.URL, Data: article.Data, Error: netScraper.ResponseOk}
err = Post(c.IP, result)
if err != nil {
time.Sleep(time.Duration(10) * time.Second) // sleep incase the WIFI is just down
err = Post(c.IP, result)
if err != nil {
log.Error(err)
}
}
}
}
// Get the server for an article to scrape.
func Get(target string) (netScraper.Request, error) {
c := &http.Client{}
// get next work unit
resp, err := c.Get(target)
if err != nil {
return netScraper.EmptyRequest(), err
}
defer resp.Body.Close()
if resp.StatusCode != 200 {
log.Error("oh nose, did not get OK status:", resp.StatusCode)
}
js, err := ioutil.ReadAll(resp.Body)
toDo := netScraper.Request{}
err = json.Unmarshal(js, &toDo)
if err != nil {
return netScraper.EmptyRequest(), err
}
return toDo, err
}
// handles scraped articles
// TODO: think about where this should be
func handleScrapedArticle(article scraper.Article) {
if err := scraper.CheckFile(article.GetData()); err != nil {
log.Warn("when checking article", article.GetTitle(), "got err:", err)
}
if err := storeArticle(article); err != nil {
log.Error("failed to write article", article.GetTitle(), ":", err)
return
}
}
// helper to push article updates
func (j Jefe) updateStatus(name string, status int) {
// note that exposed methods need to protect access
if j.openRequests[name] == nil {
// if not in open requests
return
}
select {
case j.openRequests[name] <- status:
default:
// this is a big issue because the signal chan should not be blocking
log.Error("could not send status for article", name)
}
}
func (task *SchedulableRSS) Run(scheduler *scheduler.Scheduler) {
err := scraper.UpdateRSS(task.rss)
if err != nil {
log.Error("error updating rss stories:", err)
// requeue
task.start = time.Now()
task.rss.GetChannel().ClearArticles()
go scheduler.Add(task)
return
}
// mark all articles as not in list
for key := range task.oldArticles {
task.oldArticles[key] = false
}
// schedule any new articles
// an article is new if it wasn't in the last RSS ping
delay := 60 // TODO: create legitimate task delays
for i := 0; i < task.rss.GetChannel().GetNumArticles(); i++ {
article := task.rss.GetChannel().GetArticle(i)
if _, inOld := task.oldArticles[article.GetLink()]; !inOld {
toSchedule := CreateSchedulableArticle(article, delay, task.j)
delay += 600
go scheduler.Add(toSchedule)
}
// add or update what we found
task.oldArticles[article.GetLink()] = true
}
// remove any articles not in the set
for key, inList := range task.oldArticles {
if !inList {
delete(task.oldArticles, key)
}
}
// reschedule this task
if task.IsLoopable() && scheduler.IsRunning() {
task.start = time.Now()
task.rss.GetChannel().ClearArticles()
go scheduler.Add(task)
}
}
func (task rssMonitor) didChange() (bool, error) {
err := scraper.UpdateRSS(task.rss)
if err != nil {
log.Error("error reading rss:", err)
return false, err
}
// mark all articles as not in list
for key := range task.oldArticles {
task.oldArticles[key] = false
}
// an article is new if it wasn't in the last RSS ping
found := false
for i := 0; i < task.rss.GetChannel().GetNumArticles(); i++ {
article := task.rss.GetChannel().GetArticle(i)
if _, inOld := task.oldArticles[article.GetLink()]; !inOld {
found = true
}
// add or update what we found
task.oldArticles[article.GetLink()] = true
}
// remove any articles not in the set
for key, inList := range task.oldArticles {
if !inList {
delete(task.oldArticles, key)
}
}
if found {
log.Info("found new article")
}
task.rss.GetChannel().ClearArticles()
return found, nil
}