JANUS WEB SCREEN
Define Janus Legacy page characteristics
The JANUS WEB SCREEN command sets parameters that control the mapping of 3270 screens to HTML, for Janus Web Legacy Support and Janus Web Legacy XML Support.
Syntax
JANUS WEB portname SCREEN [method] url - [AUTOPF [ON | TEXT | LINK | OFF] ] - [BGCOLOR color] - [BRIGHT color] - [BROWSER [NOT] type [PRE | POST ver.rel]] [OR ...] - [CSS url] - [CSSINSP | NOCSSINSP | AUTOCSSINSP] - [CSSTITLECLASS class] - [CSSTITLEDIV | CSSTITLESPAN] - [EXITURL url] - [HEADJS url] - [HOVER color] - [HOVERBG color] - [KBGCOLOR color] - [KEYLOC where] - [KHOVER color] - [KHOVERBG color] - [KTEXT color] - [LEGBL | NOLEGBL] - [LEGCSS | NOLEGCSS] - [LEGJS | NOLEGJS] - [LEGREV | NOLEGREV] - [LEGUS | NOLEGUS] - [ONLOAD text] - [PREJS url] - [POSTJS url] - [SCREEN | NOSCREEN] - [SCREENREDIR | NOSCREENREDIR] - [SCREENURL | NOSCREENURL] - [STIMEOUT seconds] - [STIMEOUTURL url] - [TEXT color] - [TITLE title] - [UBGCOLOR color] - [UBRIGHT color] - [UTEXT color] - [XMLSCREEN | NOXMLSCREEN] - [XMLSCREENFIELD | NOXMLSCREENFIELD] - [XMLNULLSCANCEL | XMLNULLSSEND] - [XMLNULLSSTRIP | XMLNULLSBLANK] - [3270color HTMLcolor] - [3270key label]
The portname, method, and url settings are described under the JANUS WEB command.
Note: In addition, a JANUS WEB SCREEN command must include at least one of the parameters described in the individual subsections that follow.
AUTOPF setting
This parameter indicates whether Janus Web Legacy Support should look for PF key labels at the bottom of 3270 screens to use for labels for the buttons that correspond to 3270 PF keys.
Possible values for setting are:
| OFF | If AUTOPF is set to OFF (the default setting), PF keys are simply labelled PF1, PF2, etc. |
|---|---|
| TEXT | The AUTOPF TEXT setting causes Janus to label the keys with the text at the bottom of 3270 screens using a heuristic algorithm. For example, a line at the bottom of a 3270 screen that contained the following text would cause keys corresponding to PF1, PF3, PF7, and PF8 to be labelled "Help", "Quit", "Forward," and "backward", respectively:
1/Help 3/Quit 7/Forward 8/Backward |
| ON | The AUTOPF ON setting is the same as AUTOPF TEXT, except the function key precedes the text label. For example, PF3 - Quit is displayed rather than Quit. This can eliminate the confusion caused by help text that refers to function keys by name. For example, the text Hit PF3 to quit could be confusing to an end-user if PF3 does not appear in the button label. |
| LINK | The AUTOPF LINK setting is the same as AUTOPF TEXT, except the function key labels are turned into hyper-text links, so the end-user can simply click on the text to get the required function key. |
The algorithm for locating PF key labels is heuristic and might fail on occasion. In such cases, do either of these:
- Use explicit PF key mappings with either JANUS WEB SCREEN rules or using the $Web_Screen function.
- Contact Sirius Software technical support to determine the feasibility of enhancing the label detection algorithm.
No buttons are displayed for any PF keys for which no labels are found. AUTOPF ON or AUTOPF TEXT overrides any explicit function key labels set by JANUS WEB SCREEN PFxx commands. That is, these explicit settings are ignored when AUTOPF ON or AUTOPF TEXT is set. The explicit settings, however, become active if AUTOPF is set to OFF with a $Web_Screen function.
AUTOPF processing does not affect the label for the ENTER key button and the label, or presence, of the attention key button.
BGCOLOR color
This parameter sets the background color for the HTML forms that contain the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
color is not checked for validity. The specified value is simply placed literally after a <body bgcolor= tag in generated HTML.
The default background color is #300000, which is black with a very slight reddish tint.
BRIGHT color
This parameter sets the color for fields that are set to BRIGHT in the HTML forms containing the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
color is not checked for validity. The specified value is simply placed literally after a <font color=" tag in generated HTML.
If a BRIGHT color is not specified, bright fields are displayed the same as regular dim fields, the color of which is controlled by the TEXT parameter.
BROWSER [NOT] type [PRE | POST ver.rel]]
This parameter indicates that the JANUS WEB SCREEN rule only applies to browsers of a particular type. The browser "brands" recognized by Janus Web Server]] are:
| IE | Microsoft's Internet Explorer®. |
|---|---|
| NS | Netscape Communication Corporation's Netscape Navigator® which is a component of Netscape Communicator®. |
| OPERA | Opera Software ASA's Opera® |
Rules can be made to apply to all browsers of a particular brand:
JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER IE ...
Or, for all releases of a particular brand before a particular release:
JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER NS PRE 6 ...
Or, for all releases of a particular brand at or after a particular release:
JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER OPERA POST 5.1 ...
Or, for all browsers not of a particular brand:
JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER NOT NS ...
Or, for all browsers not of specific releases of a brand:
JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER NOT NS POST 6 ...
The PRE or POST version could simply be an integer like 4, 5, or 6, or it could a decimal value with a single decimal place like 5.1, 6.2, or 4.5. PRE is always exclusive, POST is always inclusive.
A set of conditions, one for each browser brand supported, can be combined with the OR keyword:
JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER NS POST 6 OR - NOT IE ... JANUS WEB WEBPORT SCREEN /MUMBLE/* BROWSER IE POST 4.5 OR - NS POST 6 OR - OPERA POST 5 ...
The BROWSER parameter is useful for specifying screen settings that are specific to a particular browser or set of browsers.
CSS url
This parameter indicates a URL that is to be used as an external stylesheet for Janus Web Server Legacy pages. This URL can be relative or absolute, though it should be kept in mind that a relative URL is relative to the path for the URL that brought up the legacy page. If the external style sheet is to be served from the same port as the legacy URL, http:// and the host name need not be included. The style sheet can also be served by a completely different server.
There is empirical evidence that at least some releases of Internet Explorer® do not cache style sheets that are specified in mixed case.
The CSS parameter causes Janus Web Server Legacy Support to produce very different HTML pages than it otherwise would, and all the JANUS WEB SCREEN parameters that set things like colors and hover effects are meaningless if CSS is specified.
Using an external stylesheet has many benefits:
- It reduces the size of the HTML sent for each screen.
- It allows much more flexibility in what can be customized.
- It uses a standard grammar (CSS) for specifying legacy page layouts rather than a Janus Web Server specific set of rules.
CSSINSP | NOCSSINSP | AUTOCSSINSP
This parameter overrides the default or explicit JANUS DEFINE setting of the CSSINSP/NOCSSINSP/AUTOCSSINSP parameter.
CSSTITLECLASS class
This parameter sets the class to be used for the title line when using an external style sheet. The default class for the title line is title.
The main reason to use CSSTITLECLASS is to change the appearance of the title line between applications or within an application (via $Web_Screen) as some sort of indicator to the end-user.
This parameter has no effect if an external style sheet is not being used.
CSSTITLEDIV or CSSTITLESPAN
This parameter overrides the default or explicit JANUS DEFINE setting of the CSSTITLEDIV/CSSTITLESPAN parameter.
EXITURL url
This parameter sets the URL to which the browser is re-directed if the 3270 session requests a line-mode (non-full-screen) input from the user (and hence has presumably exited).
Note: If no EXITURL is specified and the 3270 application exits to command mode, Janus Web Server simply returns an empty page, which can be quite confusing to the end-user.
HEADJS url, PREJS url, and POSTJS url
This option indicates a URL that contains JavaScript that is to be embedded in a Janus Web Legacy page via a <script src="..."> tag. The HEADJS JavaScript is embedded immediately before the <head> tag, the PREJS JavaScript is embedded immediately before the <pre> tag that starts the actual screen data, and the POSTJS JavaScript is embedded immediately after the tag that ends the screen data.
url can be a relative or absolute URL, though note that a relative URL will be relative to the path for the URL that brought up the legacy page.
If the JavaScript is to be served from the same port as the legacy URL, http:// and the host name need not be included. The JavaScript can also be served by a completely different server.
The HEADJS, PREJS, and POSTJS parameters make it possible to add information to a legacy screen such as navigation bars, graphics, or explanatory text without using frames, though one could even combine frames and PREJS and/or POSTJS. Typically, the HEADJS parameter specifies a JavaScript method that is invoked by a <body> onload attribute as set from the ONLOAD parameter. Such a JavaScript method could even be used to modify the HTML generated by Janus Web Legacy Support, though how this would be accomplished is beyond the scope of this reference.
HOVER color
This parameter sets the text color for input fields that displays either when the mouse moves over them or when they get focus via a tab key or some other means. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "color:" keyword for "input:hover" and "input:focus" elements in a <style> section.
If HOVER is not specified, no hover color is set.
HOVER can be useful in Janus Web Legacy pages, because by default borders are not displayed on input fields in the same way they are not displayed on a 3270 screen, so there is no end-user feedback indicating which areas are unprotected. HOVER provides such feedback.
Support for the hover action varies widely from browser to browser.
HOVERBG color
This parameter sets the background color for input fields that displays either when the mouse moves over them or when they get focus via a tab key or some other means. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "color:" keyword for "input:hover" and "input:focus" elements in a "<style>" section.
If HOVERBG is not specified, no hover background color is set.
HOVERBG can be useful in Janus Web Legacy pages, because by default borders are not displayed on input fields in the same way they are not displayed on a 3270 screen, so there is no end-user feedback indicating which areas are unprotected. HOVERBG provides such feedback.
Support for the hover action varies widely from browser to browser.
KBGCOLOR color
This parameter sets the background color for submit buttons (keys) in the HTML forms containing the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "background:" keyword for "input.key" elements in a "<style>" section — submit buttons are <input> fields with class="key" in Janus Web Legacy pages.
If KBGCOLOR is not specified, "#D0D0D0", a grey color, is used.
KEYLOC where
This parameter specifies the position of the PF key submit buttons on a legacy screen. Valid values for KEYLOC are TOP, BOTTOM, LEFT, RIGHT, and NONE.
If NONE is specified, no PF key submit buttons appear on legacy screens. Then, unless buttons are made available with a PREJS or POSTJS "wrapper" none will be available to end-users.
KHOVER color
This parameter sets the text color that submit buttons (keys) display when the mouse moves over them. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "color:" keyword for "input.key:hover" and "input.key:focus" elements in a "<style>" section — submit buttons are <input> fields with class="key" in Janus Web Legacy pages.
If KHOVER is not specified, no hover color is set.
Support for the hover action varies widely from browser to browser.
KHOVERBG color
This parameter sets the background color that submit buttons (keys) display when the mouse moves over them. color/var> can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "background:" keyword for "input:hover" and "input:focus" elements in a "<style>" section — submit buttons are <input> fields with class="key" in Janus Web Legacy pages.
If KHOVERBG is not specified, no hover background color is set.
Support for the hover action varies widely from browser to browser.
KTEXT color
This parameter sets the text color for submit buttons (keys) in the HTML forms containing the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "color:" keyword for "input.key" elements in a "<style>" section — submit buttons are <input> fields with class="key" in Janus Web Legacy pages.
If KTEXT is not specified, "#000000", black, is used.
LEGBL | NOLEGBL
This parameter overrides the default or explicit JANUS DEFINE setting of the LEGBL/NOLEGBL parameter.
LEGCSS | NOLEGCSS
This parameter overrides the default or explicit JANUS DEFINE setting of the LEGCSS/NOLEGCSS parameter.
LEGJS | NOLEGJS
This parameter overrides the default or explicit JANUS DEFINE setting of the LEGJS/NOLEGJS parameter.
LEGREV | NOLEGREV
This parameter overrides the default or explicit JANUS DEFINE setting of the LEGREV/NOLEGREV parameter.
LEGUS | NOLEGUS
This parameter overrides the default or explicit JANUS DEFINE setting of the LEGUS/NOLEGUS parameter.
ONLOAD text
This parameter indicates text that should be included in the onload attribute of the <body> tag in the HTML generated by Janus Web Legacy Support.
Typically, Janus Web Server generates an onload attribute to invoke a method to position the cursor. In such a case, the text specified in the ONLOAD parameter is placed after the cursor positioning method invocation. On occasion, the cursor cannot be positioned, so no onload attribute is be placed in the <body> tag. In such a case, if an ONLOAD parameter is in effect, an onload attribute is added to the <body> tag containing just the text after the ONLOAD tag.
Typically, the ONLOAD parameter is used to invoke a method defined in JavaScript and retrieved as a result of the HEADJS parameter.
SCREEN | NOSCREEN
This parameter overrides the default or explicit JANUS DEFINE setting of the SCREEN/NOSCREEN parameter.
SCREENREDIR | NOSCREENREDIR
This parameter overrides the default or explicit JANUS DEFINE setting of the SCREENREDIR/NOSCREENREDIR parameter.
SCREENURL | NOSCREENURL
This parameter overrides the default or explicit JANUS DEFINE setting of the SCREENURL parameter.
STIMEOUT seconds
This parameter sets the number of seconds of inactivity after which a Janus Web Legacy session is terminated. Since it is quite easy for an end-user to start a 3270 session in a browser and forget about it, a session timeout is essential to prevent all available SDAEMON threads from being used by forgotten 3270 sessions.
The default STIMEOUT for a URL is the port STIMEOUT setting, which is specified on the JANUS DEFINE command. The default STIMEOUT setting for a port is 900 (seconds), or 15 minutes.
STIMEOUTURL url
This parameter sets the URL to which the browser is re-directed if the 3270 session times out, or if it is terminated for some other reason, such as a BUMP or the cycling of an Online.
If no STIMEOUTURL is specified and the 3270 session is no longer available when the end-user submits the form associated with that session, Janus Web Server returns a standard HTML page that indicates that the session is no longer available and might have timed out. Unfortunately, because this is a generic page, this page contains no hypertext links that allow the user to restart the session or to get back to some standard home page. STIMEOUTURL allows a site to provide a customized timeout page that contains hypertext links to the appropriate pages.
TEXT color
This parameter sets the text color for the HTML forms that contains the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after a <body text= tag in generated HTML.
The default text color is #ffffd8, which is an off-white color.
The text color is only used for line-mode data, that is, data produced from Model 204 error messages, PRINT statements, or WRITE TERMINAL statements. The color of text in screens produced with READ SCREEN statements is controlled by the color settings in the screen definition and by the default color mappings or by the mappings set in the JANUS WEB SCREEN command.
TITLE title
This parameter sets the title for the HTML form that contains the mapped 3270 screens. If this is not set, Janus Web Server uses the title specified in the TITLE statement of the screen definition. If that TITLE statement is not present, Janus Web Server uses a default title of "Janus Web Full Screen".
UBGCOLOR color
This parameter sets the background color for input fields in the HTML forms that contain the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "background:" keyword for "input" elements in a "<style>" section.
If UBGCOLOR is not specified, the color specified for BGCOLOR is used. If the BGCOLOR color was not specified, #300000 (black with a very slight reddish tint) is used for both.
UBRIGHT color
This parameter sets the text color for input fields (the U stands for "Unprotected") in the HTML forms that contain the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "color:" keyword in a "style" attribute for <input> tags.
If UBRIGHT is not specified, the color specified for BRIGHT is used. If the BRIGHT color was not specified, the regular dim text color is used for both.
UTEXT color
This parameter sets the text color for input fields (the U stands for Unprotected) in the HTML forms that contain the 3270 screens. color can be a color name such as red, or it can be an RGB code such as #FF0000.
The color value is not checked for validity. The specified value is simply placed literally after the "color:" keyword for "input" elements in a <style> section.
If UTEXT is not specified, the color specified for TEXT is used. If the TEXT color was not specified, #FFFFD8
(slightly off-white) is used for both.
XMLSCREEN | NOXMLSCREEN
This parameter overrides the default or explicit JANUS DEFINE setting of the XMLSCREEN/NOXMLSCREEN parameters.
XMLSCREENFIELD | NOXMLSCREENFIELD
This parameter overrides the default or explicit JANUS DEFINE setting of the XMLSCREENFIELD/NOXMLSCREENFIELD parameters.
XMLNULLSCANCEL | XMLNULLSSEND
This parameter overrides the default or explicit JANUS DEFINE setting of the XMLNULLSCANCEL/XMLNULLSSEND parameters.
XMLNULLSSTRIP | XMLNULLSBLANK
This parameter overrides the explicit JANUS DEFINE setting of the XMLNULLSSTRIP or XMLNULLSBLANK parameter.
3270color HTMLcolor
This parameter sets the mapping of 3270 colors to HTML colors for the HTML forms that contain the 3270 screens.
3270color can be BLUE, RED, PINK, GREEN, TURQUOISE, TURQ (a synonym for TURQUOISE), YELLOW, or WHITE. HTMLcolor can be a color name such as red, or it can be an RGB code such as #FF0000.
The HTMLcolor value is not checked for validity. The specified value is simply placed literally after a <font color= tag in generated HTML.
The default color mappings are:
| 3270 color | HTML color |
|---|---|
| Blue | #00FFFF |
| Green | #00C000 |
| Pink | #FF80FF |
| Red | #FF0000 |
| Turquoise | #00C0C0 |
| White | #FFFFFF |
| Yellow | #FFFF00 |
The color mappings are also applied to the text in input fields.
3270key label
This parameter sets the label for the HTML buttons associated with 3270 keys. Valid 3270 keys are PF1 through PF24, ENTER, ATTENTION, and ATTN (a synonym for ATTENTION). Excepting the ENTER key and ATTENTION key settings, these labels are ignored if AUTOPF is set to ON or TEXT.
If a label contains blanks, it must be enclosed in single-quotes.
The default labels are PF1 through PF24 for the PF keys, and Enter for the ENTER key.
No attention button is available on a mapped 3270 screen unless the ATTENTION or ATTN parameter is set.
Examples
It's easy to configure a Janus Web Legacy application so the generated HTML looks nice and conforms to your expectations and in-house look-and-feel. Typically you associate a 3270-based application with a URL using a JANUS WEB ON rule, then specify screen characteristics for the APSY that is launched by that command. The following ON rule and SCREEN rule create and customize a Janus Web Legacy application:
JANUS WEB myport ON /SIRSCAN CMD SIRSCAN JANUS WEB JANWEBS SCREEN /SIR* - EXITURL 'https://sirius-software.com/goodbye_visitor.html' - EXITKEY 'Exit Subsystem' - AUTOPF ON - BGCOLOR '#ffff99' - TEXT '#000000' - BLUE '#000066' - GREEN '#006600' - PINK '#ff80ff' - RED '#ff0000' - TURQUOISE '#0033ff' - WHITE '#0000ff' - YELLOW '#ffff00'