Blocks

Extract HTML

The extract HTML step: scrape values out of an HTML document with CSS selectors — text, markup, or attributes, single or every match.

Parse an HTML string and pull values out with CSS selectors — the scraping companion to web request.

Config

The extract HTML step in the Inspector The HTML source expression plus one row per value to extract.

  • HTML source — an expression returning the HTML string — usually the upstream web request's body: payload["body"].

  • Extractions — one row per value: a field name, a CSS selector, and a return mode:

    • text — the element's visible text
    • html — its markup
    • attribute — an attribute value (also set which one, e.g. href)

    Add return_array: true on a row to collect every match as a list instead of the first.

Output

One key per extraction:

{ "title": "Acme quarterly report",
  "links": ["https://…", "https://…"] }

Missing matches are null (single) or [] (with return_array).

Patterns

  • Page scrape — web request → extract HTML (title, price, availability) → branch on the value.
  • Link harvest — extract every a with attribute: href + return_array → loop over the URLs → fetch each.

Gotchas

  • Selectors run against the HTML the server sent — JavaScript-rendered content isn't there. If the value only appears after scripts run, look for the site's JSON API (often visible in the page source) and use web request directly.
  • Sites change their markup without notice — prefer stable anchors (ids, data-* attributes) over brittle positional selectors, and expect null when the page shifts.
‹ Merge If / else ›