Files: 4dbb2a6693e61517c65a6eb549c9f0d8acf437b7 / state / obs.js
2600 bytesRaw
1 | var PullObv = require('pull-obv') |
2 | var threadReduce = require('ssb-reduce-stream') |
3 | var pull = require('pull-stream') |
4 | var Next = require('pull-next') |
5 | |
6 | var nest = require('depnest') |
7 | |
8 | function isObject (o) { |
9 | return 'object' === typeof o |
10 | } |
11 | |
12 | exports.gives = nest('state.obs.threads', true) |
13 | |
14 | exports.needs = nest({ |
15 | 'message.sync.unbox': 'first', |
16 | 'sbot.pull.log': 'first' |
17 | }) |
18 | |
19 | exports.create = function (api) { |
20 | var threadsObs |
21 | |
22 | function createStateObs (threadReduce, createStream, initial) { |
23 | var lastTimestamp = initial ? initial.last : Date.now() |
24 | var firstTimestamp = initial ? initial.first || Date.now() : Date.now() |
25 | |
26 | function unbox () { |
27 | return pull( |
28 | pull.map(function (data) { |
29 | // lastTimestamp = data.timestamp |
30 | if(isObject(data.value.content)) return data |
31 | return api.message.sync.unbox(data) |
32 | }), |
33 | pull.filter(Boolean) |
34 | ) |
35 | } |
36 | |
37 | var threadsObs = PullObv( |
38 | threadReduce, |
39 | pull( |
40 | Next(function () { |
41 | return createStream({reverse: true, limit: 500, lt: lastTimestamp}) |
42 | }), |
43 | pull.through(function (data) { |
44 | lastTimestamp = data.timestamp |
45 | }), |
46 | unbox() |
47 | ), |
48 | //value recovered from localStorage |
49 | initial |
50 | ) |
51 | |
52 | //stream live messages. this *should* work. |
53 | //there is no back pressure on new events |
54 | //only a show more on the top (currently) |
55 | pull( |
56 | Next(function () { |
57 | return createStream({limit: 500, gt: firstTimestamp, live: true}) |
58 | }), |
59 | pull.drain(function (data) { |
60 | if(data.sync) return |
61 | firstTimestamp = data.timestamp |
62 | threadsObs.set(threadReduce(threadsObs.value, data)) |
63 | }) |
64 | ) |
65 | |
66 | return threadsObs |
67 | } |
68 | |
69 | |
70 | return nest('state.obs.threads', function buildThreadObs() { |
71 | if(threadsObs) return threadsObs |
72 | |
73 | // var initial |
74 | // try { initial = JSON.parse(localStorage.threadsState) } |
75 | // catch (_) { } |
76 | // |
77 | |
78 | initial = {} |
79 | |
80 | threadsObs = createStateObs(threadReduce, api.sbot.pull.log, initial) |
81 | |
82 | threadsObs(function (threadsState) { |
83 | if(threadsState.ended && threadsState.ended !== true) |
84 | console.error('threadObs error:', threadsState.ended) |
85 | }) |
86 | |
87 | // var timer |
88 | // //keep localStorage up to date |
89 | // threadsObs(function (threadsState) { |
90 | // if(timer) return |
91 | // timer = setTimeout(function () { |
92 | // timer = null |
93 | // threadsState.last = lastTimestamp |
94 | // console.log('save state') |
95 | // localStorage.threadsState = JSON.stringify(threadsState) |
96 | // }, 1000) |
97 | // }) |
98 | // |
99 | |
100 | return threadsObs |
101 | }) |
102 | } |
103 | |
104 | |
105 | |
106 | |
107 |
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