git ssb

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/* ssb-about
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 * factored out of ssb-notifier
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 *
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 * TODO:
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 * - publish as own module
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 * - handle live updates and reconnecting
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 * - deprecate when ssb-names is used in scuttlebot
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 */
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var pull = require('pull-stream')
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var cat = require('pull-cat')
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module.exports = function (sbot, myId) {
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  var cache = {/* id: about */}
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  var callbacks = {/* id: [callback] */}
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  function getAbout(id, cb) {
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    if (id in cache)
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      return cb(null, cache[id])
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    if (id in callbacks)
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      return callbacks[id].push(cb)
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    var cbs = callbacks[id] = [cb]
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    getAboutFull(sbot, myId, id, function (err, about) {
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      var about = !err && (cache[id] = about)
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      while (cbs.length)
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        cbs.pop()(err, about)
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    })
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  }
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  getAbout.getName = function (id, cb) {
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    getAbout(id, function (err, about) {
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      cb(err, about && about.name)
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    })
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  }
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  getAbout.getImage = function (id, cb) {
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    getAbout(id, function (err, about) {
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      cb(err, about && about.image)
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    })
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  }
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  return getAbout
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}
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function truncate(str, len) {
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  str = String(str)
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  return str.length < len ? str : str.substr(0, len-1) + '…'
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}
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// Get About info (name and icon) for a feed.
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function getAboutFull(sbot, source, dest, cb) {
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  var name, image
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  pull(
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    cat([
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      // First get About info that we gave them.
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      sbot.links({
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        source: source,
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        dest: dest,
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        rel: 'about',
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        values: true,
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        reverse: true
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      }),
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      // If that isn't enough, then get About info that they gave themselves.
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      sbot.links({
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        source: dest,
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        dest: dest,
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        rel: 'about',
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        values: true,
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        reverse: true
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      }),
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    ]),
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    pull.filter(function (msg) {
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      return msg && msg.value.content && (!name || !image)
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    }),
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    pull.drain(function (msg) {
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      var c = msg.value.content
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      if (!name) {
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        name = c.name
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      }
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      if (!image) {
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        image = c.image ? c.image.link : c.image
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        // var imgLink = mlib.link(c.image, 'blob')
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        // image = imgLink && imgLink.link
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      }
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    }, function (err) {
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      if (err) return cb(err)
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      cb(null, {name: name || truncate(id, 8), image: image})
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    })
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  )
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}
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