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Async-Awaitifying Pico-Go

Rationale

There is a signficant maintenance overhead with the inherited Pymakr code-base. It's very, very heavily callback-based and callbacks can traverse multiple levels of code.

Making changes, especially those which should rightly be asynchronous, is really hard work and it's too tempting to write synchronous code to avoid the pain of refactoring and adding extra layers of callback spaghetti.

If the goal is to evolve Pico-Go and keep it first class, we can't be hampered with this legacy.

Approach

A three-phase approach will be used: the first is all about laying async-await groundwork and the second is about switching to it.

Work is now complete!

Phase 1

  • For each method(cb) , add a methodAsync() ;
  • Make method(cb) call methodAsync() (using then and catch) instead of doing the work directly. For example:
  send(msg, cb) {
    this.sendAsync(msg, cb != undefined)
      .then(() => {
        if (cb) cb();
      })
      .catch(err => {
        if (cb) cb(err);
      });
  }

  async sendAsync(msg, drain = true) {
    let data = Buffer.from(msg, 'binary');
    await this.sendRawAsync(data, drain);
  }

This should ensure that nothing breaks even though things are still a work-in-progress.

Phase 2

  • Systematically replace callback-based methods with their async equivalents;
  • Remove callback-based methods;
  • Rename async methods so they lose their Async suffix.

Phase 3

  • Audit of synchronous code that should really be asynchronous.
  • Code changes to support findings.

Additional Goals

Additionally, and throughout both phases, the opportunity will be taken to normalise the code, e.g.:

  • using import instead of a mixture if that and require;
  • enforcing the use of trailing semi-colons;
  • using let and const instead of var;
  • using single quotes consistently for strings;
  • Using PascalCase for classes and camelCase for variables and methods, instead of stuff_like_this;
  • generally beautifying code to give consistent presentation.

Progress

Work is now complete!

.
├── board
│   ├── authorize.js              [Phase 3 Complete]
│   ├── project-status.js         [Phase 3 Complete]
│   ├── pyboard.js                [Phase 3 Complete]
│   ├── runner.js                 [Phase 3 Complete]
│   ├── shell.js                  [Phase 3 Complete]
│   └── sync.js                   [Phase 3 Complete]
├── connections
│   ├── telnet
│   │   ├── format.js             [No work required]
│   │   ├── telnetcli.js          [No work required]
│   │   └── util-telnet.js        [No work required]
│   ├── pyserial.js               [Phase 3 Complete]
│   ├── pysocket.js               [Phase 3 Complete]
│   └── pytelnet.js               [Phase 3 Complete]
├── helpers
│   ├── logger.js                 [Phase 3 Complete]
│   └── utils.js                  [Phase 3 Complete]
├── main
│   ├── api-wrapper.js            [Phase 3 Complete]
│   ├── panel-view.js             [Phase 3 Complete]
│   ├── settings-wrapper.js       [Phase 3 Complete]
│   └── terminal.js               [Phase 3 Complete]
├── stubs
│   └── stubs-manager.js          [Phase 3 Complete]
├── activator.js                  [Phase 3 Complete]
├── config.js                     [Phase 3 Complete]
└── pymakr.js                     [Phase 3 Complete]