Webpage Retriever

This node can be used to retrieve webpages by issuing HTTP GET requests and parsing the requested HTML webpages. For parsing, jsoup is used as library which implements the WHATWG HTML5 specification. The parsed HTML will be cleaned by removing comments and, optionally, replacing relative URLs by absolute ones.

By default, the output table will contain a column with the parsed HTML converted into XHTML. However, you can specify to get the parsed HTML as string output instead.

The node allows you to either send a request to a fixed URL (which is specified in the dialog) or to a list of URLs provided by an optional input table. Every URL will result in one request which in turn will result in one row in the output table. You can define custom request headers in the dialog.

The node supports several authentication methods, e.g. BASIC and DIGEST. Other authentication methods may be provided by additional extensions.

Cookies can be send to the server via the Request Header tab by setting the "Cookie" header. In order to receive cookies, set the "Extract cookies" option. Any cookies sent by the server are then extracted and appended as a List Cell in the output.

Input ports

1. Type: Table
   Table
   Optional data table containing the variable parameters of the requests.

Output ports

1. Type: Table
   Webpage Retriever results
   Data table containing the parsed HTML either as string or as XHTML and optionally the cookies as list of strings.

External resources

• KNIME E-Learning Course: Sending a GET Request to a REST service