from html

Extracts data from HTML files using CSS selectors.

Behavior:

This command converts HTML content into TSV format using three different modes:

1. Query Mode: For quick extraction of specific elements.
2. Table Mode: For automatically converting HTML tables (<table>).
3. Struct Mode: For extracting lists of objects into rows and columns.

Input:

• Reads from standard input if no input file is given or if the input file is ‘stdin’.
• Supports plain text HTML files.

Output:

• Writes to standard output by default.
• Use --outfile / -o to write to a file ([stdout] for screen).

Query Mode:

• Activated by the --query / -q flag.
• Syntax: selector [display_function]
• Selectors: Standard CSS selectors (e.g., div.content, #main a).
• Display Functions:
  • text{} or text(): Print the text content of the selected elements.
  • attr{name} or attr("name"): Print the value of the specified attribute.
  • If omitted, prints the full HTML of selected elements.
• Empty results are kept by default (prints blank lines for empty text or missing attributes).
• For advanced CSS selector reference, see: docs/selectors.md.

Table Mode:

• Activated by the --table flag.
• Extracts data from HTML <table> elements.
• Use --index N to select the N-th matched table (1-based). Implies --table.
• Use --table=<css> to target specific tables (e.g., div.result table).

Struct Mode (List Extraction):

• Activated by using --row and --col flags.
• Designed to extract repetitive structures (like cards, list items) into a TSV table.
• --row <selector>: Defines the container for each record (e.g., div.product, li).
• --col "Name:Selector [Function]": Defines a column in the output TSV.
  • Name: The column header name.
  • Selector: CSS selector relative to the row element.
  • Function: text{} (default) or attr{name}.
  • Example: --col "Link:a.title attr{href}"
  • Missing elements or attributes result in empty TSV cells.

Input:

• Reads from files or standard input.
• Use stdin or omit the file argument to read from standard input.

Output:

• By default, output is written to standard output.
• Use --outfile to write to a file instead.

Examples:

1. Extract all links (Query Mode) tva from html -q "a attr{href}" index.html

2. Extract the first table (Table Mode) tva from html --table data.html

3. Extract product list (Struct Mode) tva from html –row “div.product-card”
   –col “Title: h2.title text{}”
   –col “Price: .price”
   –col “URL: a.link attr{href}”
   products.html