sdk.watcher.watcher

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Watcher.Watcher class

Watches a matcher function, and trigger whenever it changes from matching to not.

Signature:

export declare class Watcher<T> 

Remarks

Whenever wait resolves, it runs match, and triggers enter with the match result, or leave without, then wait again.

By default, wait is a function that resolves on every page navigation or mutation.

Example

async function step(ctx: Context) {
  const spec = {
    wait(): Promise<void> {
      return new Promise((resolve, reject) => {
        setTimeout(() => { reject() }, 5000)
      })
    },
    async match() {
      return await ctx.page.waitForSelector('#input:focus');
    },
    async enter(match): Promise<void> {
      return await match.evaluate(el => {
        alert(`you have just focused ${el.id}`);
      });
    },
    leave(match): Promise<void> {
      return new Promise(resolve => {
        alert(`you are left the input so gonna be redirected to google, just in case`);
        ctx.page.goto('https://google.com');
        resolve();
      })
    }
  };
 const watcher = new Watcher(ctx, spec);
 await watcher.start();
}

Constructors

Constructor	Modifiers	Description
(constructor)(ctx, spec)		Constructs a new instance of the Watcher class

Properties

Property	Modifiers	Type	Description
lastMatch?		T	(Optional)

Methods

Method	Modifiers	Description
getLastMatch()		Returns the last stored match, if any.
isMatching()		Checks if matcher is matching.
isRunning()		Checks if matcher is running.
start()		Starts the watcher
stop()		Stops the watcher.