git ssb

1
const pull = require('pull-stream')
2
const sort = require('ssb-sort')
3
const isPoll = require('../../isPoll')
4
const isPosition = require('../../isPosition')
5
const { ERROR_POSITION_TYPE } = require('../../types')
6
const results = require('../../position/sync/chooseOneResults')
7
8
module.exports = function (server) {
9
  return function get (key, cb) {
10
    server.get(key, (err, value) => {
11
      if (err) return cb(err)
12
13
      var poll = { key, value }
14
      if (!isPoll(poll)) return cb(new Error('scuttle-poll could not fetch, key provided was not a valid poll key'))
15
16
      pull(
17
        createBacklinkStream(key),
18
        pull.collect((err, msgs) => {
19
          if (err) return cb(err)
20
21
          cb(null, decoratedPoll(poll, msgs))
22
        })
23
      )
24
    })
25
  }
26
27
  function createBacklinkStream (key) {
28
    var filterQuery = {
29
      $filter: {
30
        dest: key
31
      }
32
    }
33
34
    return server.backlinks.read({
35
      query: [filterQuery],
36
      index: 'DTA' // use asserted timestamps
37
    })
38
  }
39
}
40
41
function decoratedPoll (rawPoll, msgs = []) {
42
  const { author, content: { title, body } } = rawPoll.value
43
44
  const poll = Object.assign({}, rawPoll, {
45
    author,
46
    title,
47
    body,
48
49
    positions: [],
50
    results: {},
51
    errors: []
52
53
    // publishPosition:  TODO ? add pre-filled helper functions to the poll?
54
  })
55
56
  // TODO add missingContext warnings to each msg
57
  msgs = sort(msgs)
58
59
  // filter position message into 'positions' and 'errors'
60
  const type = poll.value.content.pollDetails.type
61
  msgs
62
    .filter(msg => msg.value.content.root === poll.key)
63
    .forEach(position => {
64
      if (isPosition[type](position)) {
65
        // TODO validator checks right position shape, but needs to add e.g. acceptible position ranges based on poll
66
        poll.positions.push(position)
67
        return
68
      }
69
70
      if (isPosition(position)) {
71
        poll.errors.push({
72
          type: ERROR_POSITION_TYPE,
73
          message: `Position responses need to be off the ${type} type for this poll`,
74
          position
75
        })
76
      }
77
    })
78
79
  poll.results = results({ poll, positions: poll.positions })
80
81
  return poll
82
}
83