HTTP server

Description
The x3270 family supports an HTTP server. Scripts can send REST requests to the emulator via HTTP to modify the emulator or query its state.

A global HTTP server is configured via the httpd resource or the -httpd command-line option. The Script action also creates a new instance of the HTTP server for each child script to use.

For experimentation, the HTTP server can be used from an ordinary web browser. Just point a browser at the root (e.g., ) and appropriate directories will be displayed.

Note that on all platforms, lines of output from the HTTP server are separated by CR/LF sequences.

Namespace
These URLs assume that the server is set up to listen on the IPv4 loopback address, port 8080.
 * An interactive form for submitting actions to the emulator.
 * An interactive form for submitting actions to the emulator.


 * The current screen image.
 * The current screen image.


 * REST API with results returned as JSON.
 * REST API with results returned as JSON.


 * REST API with results returned as HTML.
 * REST API with results returned as HTML.


 * REST API with results returned as plain text.
 * REST API with results returned as plain text.


 * REST API with results returned as plain text, beginning with the status line.
 * REST API with results returned as plain text, beginning with the status line.

Note that when an action and parameters are passed as part of a URL, the  character must be escaped as , so it is not mistaken for the delimiter for query parameters.

REST API Examples
Requests use the HTTP GET verb. Simply add the action and parameters to the desired URL. For example, to perform the Query action with the Proxies query, with the response in HTML, use this URL: http://127.0.0.1:8080/3270/rest/html/Query(Proxies)

JSON
HTTP GET: http://127.0.0.1:8080/3270/rest/json/Query(Proxies) Result: { "status": "L U U N N 4 24 80 0 0 0x0 0.000", "result": [ "passthru no-username 3514", "http username 3128", "telnet no-username", "socks4 username 1080", "socks4a username 1080", "socks5 username 1080", "socks5d username 1080" ] }

HTML
HTTP GET: http://127.0.0.1:8080/3270/rest/html/Query(Proxies) Result: &lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"> &lt;html> &lt;head> &lt;title>Success&lt;/title> &lt;/head> &lt;body> &lt;h1>Success&lt;/h1> &lt;h2>Status&lt;/h2> &lt;pre>L U U N N 4 24 80 0 0 0x0 0.000&lt;/pre> &lt;h2>Result&lt;/h2> &lt;pre>passthru no-username 3514 http username 3128 telnet no-username socks4 username 1080 socks4a username 1080 socks5 username 1080 socks5d username 1080 &lt;/pre> &lt;hr> &lt;i>wc3270 v4.0alpha2 Sat Dec 28 05:26:41 UTC 2019 pdm - &lt;a href="http://x3270.bgp.nu/">x3270.bgp.nu&lt;/a>&lt;/i> &lt;/body> &lt;/html>

Plain text with status line
HTTP GET: http://127.0.0.1:8080/3270/rest/stext/Query(Proxies) Result: L U U N N 4 24 80 0 0 0x0 0.000 passthru no-username 3514 http username 3128 telnet no-username socks4 username 1080 socks4a username 1080 socks5 username 1080 socks5d username 1080

Plain text
HTTP GET: http://127.0.0.1:8080/3270/rest/text/Query(Proxies) Result: passthru no-username 3514 http username 3128 telnet no-username socks4 username 1080 socks4a username 1080 socks5 username 1080 socks5d username 1080

Version history
JSON support was added to x3270 4.0 in 2020.