git ssb

1
'use strict'
2
var pull = require('pull-stream')
3
var FlumeViewLevel = require('flumeview-level')
4
var pullCat = require('pull-cat')
5
var HLRU = require('hashlru')
6
var extend = require('xtend')
7
var normalizeChannel = require('ssb-ref').normalizeChannel
8
var Defer = require('pull-defer')
9
10
// HACK: pull it out of patchcore
11
var getRoot = require('patchcore/message/sync/root').create().message.sync.root
12
var getTimestamp = require('patchcore/message/sync/timestamp').create().message.sync.timestamp
13
14
module.exports = function (ssb, config) {
15
  var create = FlumeViewLevel(2, function (msg, seq) {
16
    var result = [
17
      [getTimestamp(msg), getRoot(msg) || msg.key]
18
    ]
19
    return result
20
  })
21
22
  var index = ssb._flumeUse('patchwork-roots', create)
23
24
  // cache mostly just to avoid reading the same roots over and over again
25
  // not really big enough for multiple refresh cycles
26
  var cache = HLRU(100)
27
28
  return {
29
    latest: function ({ids = [ssb.id]}) {
30
      var stream = Defer.source()
31
      getFilter((err, filter) => {
32
        if (err) return stream.abort(err)
33
        stream.resolve(pull(
34
          index.read({old: false}),
35
36
          // BUMP FILTER
37
          pull.filter(item => {
38
            if (filter && item.value && item.value) {
39
              var filterResult = filter(ids, item.value)
40
              if (filterResult) {
41
                item.value.filterResult = filterResult
42
                return true
43
              }
44
            }
45
          }),
46
47
          // LOOKUP AND ADD ROOTS
48
          LookupRoots(),
49
50
          // FILTER ROOTS
51
          pull.filter(item => {
52
            var root = item.root || item
53
            var isPrivate = root.value && typeof root.value.content === 'string'
54
55
            if (filter && root && root.value && !isPrivate) {
56
              var filterResult = filter(ids, root)
57
              if (checkReplyForcesDisplay(item) || shouldShow(filterResult)) {
58
                root.filterResult = filterResult
59
                return true
60
              }
61
            }
62
          })
63
        ))
64
      })
65
      return stream
66
    },
67
68
    read: function ({ids = [ssb.id], reverse, limit, lt, gt}) {
69
      var opts = {reverse, old: true}
70
71
      // handle markers passed in to lt / gt
72
      if (lt && typeof lt.timestamp === 'number') lt = lt.timestamp
73
      if (gt && typeof gt.timestamp === 'number') gt = gt.timestamp
74
      if (typeof lt === 'number') opts.lt = [lt]
75
      if (typeof gt === 'number') opts.gt = [gt]
76
77
      var seen = new Set()
78
      var included = new Set()
79
      var marker = {marker: true, timestamp: null}
80
81
      var stream = Defer.source()
82
83
      getFilter((err, filter) => {
84
        if (err) return stream.abort(err)
85
        stream.resolve(pull(
86
          // READ ROOTS INDEX
87
          index.read(opts),
88
89
          // BUMP FILTER
90
          pull.filter(item => {
91
            // keep track of latest timestamp
92
            marker.timestamp = item.key[0]
93
94
            if (filter && item.value && item.value) {
95
              var filterResult = filter(ids, item.value)
96
              if (filterResult) {
97
                item.value.filterResult = filterResult
98
                return true
99
              }
100
            }
101
          }),
102
103
          // LOOKUP AND ADD ROOTS
104
          LookupRoots(),
105
106
          // FILTER ROOTS
107
          pull.filter(item => {
108
            var root = item.root || item
109
            var isPrivate = root.value && typeof root.value.content === 'string'
110
111
            // skip this item if it has already been included
112
            if (!included.has(root.key) && filter && root && root.value && !isPrivate) {
113
              if (checkReplyForcesDisplay(item)) { // include this item if it has matching tags or the author is you
114
                // update filter result so that we can display the correct bump message
115
                root.filterResult = extend(item.filterResult, {forced: true})
116
                included.add(root.key)
117
                return true
118
              } else if (!seen.has(root.key)) {
119
                seen.add(root.key)
120
                var filterResult = filter(ids, root)
121
                if (shouldShow(filterResult)) {
122
                  root.filterResult = filterResult
123
                  included.add(root.key)
124
                  return true
125
                }
126
              }
127
            }
128
          }),
129
130
          // MAP ROOT ITEMS
131
          pull.map(item => {
132
            var root = item.root || item
133
            return root
134
          })
135
        ))
136
      })
137
138
      // TRUNCATE
139
      if (typeof limit === 'number') {
140
        var count = 0
141
        return pullCat([
142
          pull(
143
            stream,
144
            pull.take(limit),
145
            pull.through(() => {
146
              count += 1
147
            })
148
          ),
149
150
          // send truncated marker for resuming search
151
          pull(
152
            pull.values([marker]),
153
            pull.filter(() => count === limit)
154
          )
155
        ])
156
      } else {
157
        return stream
158
      }
159
    }
160
  }
161
162
  function shouldShow (filterResult) {
163
    return !!filterResult
164
  }
165
166
  function getThruCache (key, cb) {
167
    if (cache.has(key)) {
168
      cb(null, cache.get(key))
169
    } else {
170
      ssb.get(key, (_, value) => {
171
        var msg = {key, value}
172
        if (msg.value) {
173
          cache.set(key, msg)
174
        }
175
        cb(null, msg)
176
      })
177
    }
178
  }
179
180
  function getFilter (cb) {
181
    // TODO: rewrite contacts stream
182
    ssb.friends.get((err, friends) => {
183
      if (err) return cb(err)
184
      ssb.patchwork.getSubscriptions((err, subscriptions) => {
185
        if (err) return cb(err)
186
        cb(null, function (ids, msg) {
187
          var type = msg.value.content.type
188
          if (type === 'vote') return false // filter out likes
189
          var hasChannel = !!msg.value.content.channel
190
          var matchesChannel = (type !== 'channel' && checkChannel(subscriptions, ids, msg.value.content.channel))
191
          var matchingTags = getMatchingTags(subscriptions, ids, msg.value.content.mentions)
192
          var isYours = ids.includes(msg.value.author)
193
          var mentionsYou = getMentionsYou(ids, msg.value.content.mentions)
194
195
          var following = checkFollowing(friends, ids, msg.value.author)
196
          if (isYours || matchesChannel || matchingTags.length || following || mentionsYou) {
197
            return {
198
              matchingTags, matchesChannel, isYours, following, mentionsYou, hasChannel
199
            }
200
          }
201
        })
202
      })
203
    })
204
  }
205
206
  function LookupRoots () {
207
    return pull.asyncMap((item, cb) => {
208
      var msg = item.value
209
      var key = item.key[1]
210
      if (key === msg.key) {
211
        // already a root
212
        return cb(null, msg)
213
      }
214
      getThruCache(key, (_, value) => {
215
        cb(null, extend(msg, {
216
          root: value
217
        }))
218
      })
219
    })
220
  }
221
}
222
223
function getMatchingTags (lookup, ids, mentions) {
224
  if (Array.isArray(mentions)) {
225
    return mentions.reduce((result, mention) => {
226
      if (mention && typeof mention.link === 'string' && mention.link.startsWith('#')) {
227
        if (checkChannel(lookup, ids, mention.link.slice(1))) {
228
          result.push(normalizeChannel(mention.link.slice(1)))
229
        }
230
      }
231
      return result
232
    }, [])
233
  }
234
  return []
235
}
236
237
function getMentionsYou (ids, mentions) {
238
  if (Array.isArray(mentions)) {
239
    return mentions.some((mention) => {
240
      if (mention && typeof mention.link === 'string') {
241
        return ids.includes(mention.link)
242
      }
243
    })
244
  }
245
}
246
247
function checkReplyForcesDisplay (item) {
248
  var filterResult = item.filterResult || {}
249
  var matchesTags = filterResult.matchingTags && !!filterResult.matchingTags.length
250
  return matchesTags || filterResult.isYours
251
}
252
253
function checkFollowing (lookup, ids, target) {
254
  // TODO: rewrite contacts index (for some reason the order is different)
255
  if (!lookup) return false
256
  // HACK: only lookup the first ID until a method is added to ssb-friends to
257
  // correctly identify latest info
258
  var value = ids.slice(0, 1).map(id => lookup[id] && lookup[id][target])
259
  return value && value[0]
260
}
261
262
function checkChannel (lookup, ids, channel) {
263
  if (!lookup) return false
264
  channel = normalizeChannel(channel)
265
  if (channel) {
266
    var value = mostRecentValue(ids.map(id => lookup[`${id}:${channel}`]))
267
    return value && value[1]
268
  }
269
}
270
271
function mostRecentValue (values, timestampIndex = 0) {
272
  var mostRecent = null
273
  values.forEach(value => {
274
    if (value && (!mostRecent || mostRecent[timestampIndex] < value[timestampIndex])) {
275
      mostRecent = value
276
    }
277
  })
278
  return mostRecent
279
}
280