git ssb

1
const errors = require('./errors.json')
2
const nope = () => {}
3
4
module.exports = class Actor {
5
  /**
6
   * the Actor manages the varous message passing functions and provides
7
   * an interface for the containers to use
8
   * @param {Object} opts
9
   * @param {Object} opts.id - the UUID of the Actor
10
   * @param {Object} opts.state - the state of the container
11
   * @param {Object} opts.hypervisor - the instance of the hypervisor
12
   * @param {Object} opts.container - the container constuctor and argments
13
   */
14
  constructor (opts) {
15
    Object.assign(this, opts)
16
17
    this.ticks = 0
18
    this.running = false
19
    this.container = new this.Container(this)
20
    if (!this.hypervisor.meter) {
21
      this.incrementTicks = nope
22
    }
23
  }
24
25
  /**
26
   * Runs the shutdown routine for the actor
27
   */
28
  async shutdown () {
29
    await this.tree.set(this.id.id, [this.type, this.nonce])
30
    const state = await this.tree.get(this.id.id)
31
    return this.tree.graph.set(state.root, '2', this.storage)
32
  }
33
34
  /**
35
   * Runs the startup routine for the actor
36
   */
37
  startup () {
38
    return this.container.onStartup()
39
  }
40
41
  /**
42
   * run the Actor with a given message
43
   * @param {object} message - the message to run
44
   * @param {String} method - which method to run
45
   * @returns {Promise}
46
   */
47
  async runMessage (message) {
48
    if (message._fromTicks > this.ticks) {
49
      this.ticks = message._fromTicks
50
    }
51
    try {
52
      this.currentMessage = message
53
      await this.container.onMessage(message)
54
    } catch (e) {
55
      message.emit('execution:error', e)
56
    }
57
    message.emit('done', this)
58
  }
59
60
  /**
61
   * updates the number of ticks that the actor has run
62
   * @param {Number} count - the number of ticks to add
63
   */
64
  incrementTicks (count) {
65
    this.currentMessage.funcRef.gas -= count
66
    if (this.currentMessage.funcRef.gas < 0) {
67
      throw new Error(errors.OUT_OF_GAS)
68
    }
69
    this.ticks += count
70
  }
71
72
  /**
73
   * creates an actor
74
   * @param {Integer} type - the type id for the container
75
   * @param {Object} message - an intial [message](https://github.com/primea/js-primea-message) to send newly created actor
76
   */
77
  createActor (type, code) {
78
    const id = this._generateNextId()
79
    return this.hypervisor.createActor(type, code, id)
80
  }
81
82
  _generateNextId () {
83
    const id = {
84
      nonce: this.nonce,
85
      parent: this.id
86
    }
87
88
    this.nonce++
89
    return id
90
  }
91
92
  /**
93
   * sends a message to a given port
94
   * @param {Object} portRef - the port
95
   * @param {Message} message - the message
96
   */
97
  send (message) {
98
    message._fromTicks = this.ticks
99
    message._fromId = this.id
100
101
    this.hypervisor.scheduler.queue([message])
102
  }
103
}
104