conewsy.go

package main

import (
    "os"
    "fmt"
    "sync"

    "github.com/caser/gophernews"
    "github.com/jzelinskie/geddit"
)

var redditSession *geddit.LoginSession
var hackerNewsClient *gophernews.Client

func init() {
    hackerNewsClient = gophernews.NewClient()

    // todo: switch to OAuth2 method
    // see https://github.com/jzelinskie/geddit/blob/master/example_test.go
    var err error
    redditSession, err = geddit.NewLoginSession("redditUsername", "redditPassword", "customUserAgent")

    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }
}

type Story struct {
    title string
    url string
    author string
    source string
}

func getHnStoryDetails(id int, c chan<- Story, wg *sync.WaitGroup) {
    defer wg.Done()
    story, err := hackerNewsClient.GetStory(id)
    if err != nil {
        return
    }
    newStory := Story{
        title: story.Title,
        url: story.URL,
        author: story.By,
        source: "HackerNews",
    }
    c <- newStory
}

func newHnStories(c chan<- Story) {
    defer close(c)
    changes, err := hackerNewsClient.GetChanges()
    if err != nil {
        fmt.Println(err)
        return
    }

    var wg sync.WaitGroup
    for _, id := range changes.Items {
        wg.Add(1)
        go getHnStoryDetails(id, c, &wg)
    }

    wg.Wait()
}

func newRedditStories(c chan<- Story) {
    defer close(c)
    sort := geddit.PopularitySort(geddit.NewSubmissions)
    var listingOptions geddit.ListingOptions
    submissions, err := redditSession.SubredditSubmissions("programming", sort, listingOptions)
    if err != nil {
        fmt.Println(err)
        return
    }

    for _, s := range submissions {
        newStory := Story {
            title: s.Title,
            url: s.URL,
            author: s.Author,
            source: "Reddit /r/programming",
        }

        c <- newStory
    }
}

func outputToConsole(c <-chan Story) {
    for s := range c {
        fmt.Printf("%s: %s \nby %s on %s\n\n", s.title, s.url, s.author, s.source)
    }
}

func outputToFile(c <-chan Story, file *os.File) {
    for s := range c {
        fmt.Fprintf(file, "%s: %s \nby %s on %s\n\n", s.title, s.url, s.author, s.source)
    }
}

func main() {
    fromHn := make(chan Story, 8)
    fromReddit := make(chan Story, 8)
    toFile := make(chan Story, 8)
    toConsole := make(chan Story, 8)

    go newHnStories(fromHn)
    go newRedditStories(fromReddit)

    file, err := os.Create("codata/stories.txt")
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    go outputToConsole(toConsole)
    go outputToFile(toFile, file)

    hnOpen := true
    redditOpen := true

    for hnOpen || redditOpen {
        select {
        case story, open:= <- fromHn:
            if open {
                toFile <-story
                toConsole <-story
            } else {
                hnOpen = false
            }
        case story, open := <- fromReddit:
            if open {
                toFile <-story
                toConsole <-story
            } else {
                redditOpen = false
            }
        }
    }
}