Interface Context

Context provides a tiny layer for passing data between callbacks.

For example, the Crawler.onHTML callback function puts data into the context.

c.onHTML("a[href]", (e) => {
  // ...
  e.request.ctx.put("page_href", e.request.url);
  e.request.ctx.put("link_text", e.text);
  //...

The Crawler.onResponse callback function reads the data previously put by the Crawler.onHTML callback from the context.

c.onResponse((r) => {
  const page_href = r.request.ctx.get("page_href");
  // ...

interface Context {
    get(key: string): string;
    getAny(key: string): unknown;
    put(key: string, value: unknown): void;
}

Methods

get(key: string): string
Retrieves a string value from Context. Get returns an empty string if key not found.
Parameters
- key: string
  key to get
Returns string

getAny(key: string): unknown
Retrieves a value from Context. GetAny returns null if key not found.
Parameters
- key: string
  key to get
Returns unknown