git ssb

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var pull = require('pull-stream')
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var multicb = require('multicb')
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var cat = require('pull-cat')
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var u = require('./util')
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module.exports = About
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function About(app, myId, follows) {
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  this.app = app
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  this.myId = myId
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  this.follows = follows
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}
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About.prototype.createAboutOpStream = function (id) {
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  return pull(
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    this.app.sbot.links({dest: id, rel: 'about', values: true, reverse: true, private: true, meta: false}),
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    this.app.unboxMessages(),
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    pull.map(function (msg) {
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      var c = msg.value.content
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      if (typeof c !== 'object' || c === null) return []
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      return Object.keys(c).filter(function (key) {
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        return key !== 'about'
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          && key !== 'type'
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          && key !== 'recps'
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          && key !== 'reason'
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      }).map(function (key) {
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        var value = c[key]
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        return {
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          id: msg.key,
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          author: msg.value.author,
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          timestamp: msg.value.timestamp,
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          prop: key,
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          value: value,
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          remove: value && value.remove,
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        }
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      })
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    }),
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    pull.flatten()
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  )
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}
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About.prototype.createAboutStreams = function (id) {
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  var ops = this.createAboutOpStream(id)
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  var scalars = {/* author: {prop: value} */}
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  var sets = {/* author: {prop: {link}} */}
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  var setsDone = multicb({pluck: 1, spread: true})
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  setsDone()(null, pull.values([]))
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  return {
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    scalars: pull(
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      ops,
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      pull.unique(function (op) {
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        return op.author + '-' + op.prop + '-'
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      }),
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      pull.filter(function (op) {
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        return !op.remove
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      })
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    ),
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    sets: u.readNext(setsDone)
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  }
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}
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function computeTopAbout(aboutByFeed) {
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  var propValueCounts = {/* prop: {value: count} */}
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  var topValues = {/* prop: value */}
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  var topValueCounts = {/* prop: count */}
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  for (var feed in aboutByFeed) {
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    var feedAbout = aboutByFeed[feed]
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    for (var prop in feedAbout) {
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      var value = feedAbout[prop]
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      var valueCounts = propValueCounts[prop] || (propValueCounts[prop] = {})
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      var count = (valueCounts[value] || 0) + 1
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      valueCounts[value] = count
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      if (count > (topValueCounts[prop] || 0)) {
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        topValueCounts[prop] = count
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        topValues[prop] = value
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      }
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    }
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  }
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  return topValues
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}
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About.prototype.get = function (dest, cb) {
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  var self = this
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  var myAbout = []
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  var aboutByFeed = {}
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  var aboutByFeedFollowed = {}
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  this.follows.getFollows(this.myId, function (err, follows) {
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    if (err) return cb(err)
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    pull(
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      cat([
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        dest[0] === '%' && self.app.pullGetMsg(dest),
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        self.app.sbot.links({
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          rel: 'about',
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          dest: dest,
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          values: true,
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          private: true,
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          meta: false
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        })
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      ]),
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      self.app.unboxMessages(),
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      pull.drain(function (msg) {
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        var author = msg.value.author
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        var c = msg.value.content
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        if (!c) return
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        if (msg.key === dest && c.type === 'about') {
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          // don't describe an about message with itself
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          return
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        }
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        var about = author === self.myId ? myAbout :
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          follows[author] ?
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            aboutByFeedFollowed[author] || (aboutByFeedFollowed[author] = {}) :
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            aboutByFeed[author] || (aboutByFeed[author] = {})
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        if (c.name) about.name = c.name
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        if (c.title) about.title = c.title
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        if (c.image) {
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          about.image = u.linkDest(c.image)
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          about.imageLink = u.toLink(c.image)
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        }
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        if (c.description) about.description = c.description
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        if (c.publicWebHosting) about.publicWebHosting = c.publicWebHosting
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      }, function (err) {
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        if (err) return cb(err)
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        var destAbout = aboutByFeedFollowed[dest] || aboutByFeed[dest]
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        // bias the author's choices by giving them an extra vote
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        if (destAbout) {
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          if (follows[dest]) aboutByFeedFollowed._author = destAbout
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          else aboutByFeed._author = destAbout
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        }
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        var about = {}
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        var followedAbout = computeTopAbout(aboutByFeedFollowed)
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        var topAbout = computeTopAbout(aboutByFeed)
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        for (var k in topAbout) about[k] = topAbout[k]
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        // prefer followed feeds' choices
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        for (var k in followedAbout) about[k] = followedAbout[k]
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        // if we follow the destination/author feed, prefer its choices
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        if (follows[dest]) for (var k in destAbout) about[k] = destAbout[k]
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        // always prefer own choices
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        for (var k in myAbout) about[k] = myAbout[k]
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        cb(null, about)
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      })
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    )
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  })
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}
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