Files: d9b6113bb6b82443c2fb8a9a9b1afa58b1206f67 / portManager.js
2240 bytesRaw
1 | const Port = require('./port.js') |
2 | const ENTRY = Symbol('entry') |
3 | |
4 | // decides which message to go first |
5 | function messageArbiter (pairA, pairB) { |
6 | const portA = pairA[1] |
7 | const portB = pairB[1] |
8 | const a = portA.peek() |
9 | const b = portB.peek() |
10 | |
11 | if (!a) { |
12 | return pairB |
13 | } else if (!b) { |
14 | return pairA |
15 | } |
16 | |
17 | if (a._fromPortTicks !== b._fromPortTicks) { |
18 | return a._fromPortTicks < b._fromPortTicks ? pairA : pairB |
19 | } else if (a.priority !== b.priority) { |
20 | // decide by priority |
21 | return a.priority > b.priority ? pairA : pairB |
22 | } else if (portA.name === ENTRY) { |
23 | return pairA |
24 | } else { |
25 | return portA.name < portB.name ? pairA : pairB |
26 | } |
27 | } |
28 | |
29 | module.exports = class PortManager { |
30 | constructor (opts) { |
31 | Object.assign(this, opts) |
32 | this._portMap = new Map() |
33 | } |
34 | |
35 | async start () { |
36 | // skip the root, since it doesn't have a parent |
37 | if (this.parentPort !== undefined) { |
38 | this._portMap.set(this.parentPort, new Port(ENTRY)) |
39 | } |
40 | // map ports to thier id's |
41 | this.ports = await this.hypervisor.graph.get(this.state, 'ports') |
42 | Object.keys(this.ports).map(name => { |
43 | const port = this.ports[name] |
44 | this._mapPort(name, port) |
45 | }) |
46 | } |
47 | |
48 | _mapPort (name, portRef) { |
49 | const port = new Port(name) |
50 | this._portMap.set(portRef, port) |
51 | } |
52 | |
53 | queue (message) { |
54 | this._portMap.get(message.fromPort).queue(message) |
55 | } |
56 | |
57 | set (name, port) { |
58 | this.ports[name] = port |
59 | return this._mapPort(name, port) |
60 | } |
61 | |
62 | get (key) { |
63 | return this.ports[key] |
64 | } |
65 | |
66 | // waits till all ports have reached a threshold tick count |
67 | wait (threshold, fromPort) { |
68 | // find the ports that have a smaller tick count then the threshold tick count |
69 | const unkownPorts = [...this._portMap].filter(([portRef, port]) => { |
70 | return port.ticks < threshold && fromPort !== portRef |
71 | }) |
72 | |
73 | const promises = unkownPorts.map(async ([portRef, port]) => { |
74 | // update the port's tick count |
75 | port.ticks = await this.hypervisor.wait(portRef, threshold, this.entryPort) |
76 | }) |
77 | return Promise.all(promises) |
78 | } |
79 | |
80 | async getNextMessage () { |
81 | await this.wait(this.kernel.ticks, this.entryPort) |
82 | const portMap = [...this._portMap].reduce(messageArbiter) |
83 | return portMap[1].shift() |
84 | } |
85 | } |
86 |
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