cheatsheet.md

ServiceNow UI Developer cheat sheet

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Utility URLs

URL	Purpose
/stats.do	Quick stats
/cache.do	Clear your instance cache
/cancel_my_transaction	Cancel your currently running transaction
/cache_inspect.do	Inspect the content of various system caches
/$restapi.do	Rest API explorer

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Common directories

Path	Description
/ui.html	Static files accessible from /
/ui.jtemplates	Jelly templates
/ui.jforms	Jelly forms accessible from /
/ui.jtemplates/doctype	Doctype Jelly template overrides
/ui.jforms/doctype	Doctype Jelly form overrides

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URL resolution

1. Virtual host provider
2. Static content
3. Processor
   1. Processor table
      1. Parameter - incident.do?PARAMETER
      2. Path - PATH.do
      3. Extension - incident.EXTENSION
   2. Or a com.glide.processors extension point declared in plugin.xml
4. UI Page?
5. Jelly Form?
6. Table?
7. Table with list suffix?
8. Search suffix?
9. Update suffix?
10. ☹️ not_found.xml

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Direct UI page (no page template)

• Jelly forms with $ prefix
  • $my_form.xml => /$my_form.do
• ?sysparm_direct=true
  • $my_ui_page.do?sysparm_direct=true
• UI Pages marked direct

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Accessing URL Parameters

• RP.getParameterValue(String param)
• ${sysparm_*} (Parameter must start with sysparm_)

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Front end scripting

Selector	Usage
$(id)	prototypeJS getElementById()
$$(cssRule)	prototypeJS css selector
$j(selector)	jQuery

Common client scripting APIs

API	Description
GlideAjax	Access a service side script include
GlideURL	Create and parse urls
GlideModalForm	Display a form in a modal
g_form	GlideForm shortcut for interacting with a form
g_user	GlideUser shortcut to the current user

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Jelly scripting

Syntax	Phase
${ ... }	Phase 1
$[ ... ]	Phase 2

JEXL vs JavaScript

JEXL expressions are not JavaScript and Jelly variables are not Rhino variables. You cannot mix them.

JEXL lets you access Rhino scriptable methods and fields like gs.log() and gr.next().

JEXL methods

Method	Usage	Description
size()	${ size(jvar) }	for String, counts length for Map, counts keys for List, counts elements
empty()	${ empty(jvar) }	True if: - null, empty string - a zero length collection - a map with no keys - an empty array
.startsWith()	${ jvar.startsWith("hello") }	returns bool
.endsWith()	${ jvar.endsWith("world") }	returns bool

Jexl helpers

${AND} => &&
${LT} => <
${GT} => >
$[SP] => &nbsp;

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Jelly Escaping

JEXL output is automatically escaped. Use these prefixes to manually control how output is escaped. Refer to GlideExpressionWrapper for more detail.

	${HTML,JS:gr.getDisplayValue('short_description')}

Prefix	When to use
HTML	HTML escaping
JS	JavaScript escaping
JS_STRING	Escape a string containing JavaScript
NS	Escapes script tags for XSS prevention
JS_XML	Escaping for XML used as a javascript string
URL	For URLs
NLBR	Newline to <br/>
WBR	Insert <shy; in long sequences the browser would not break
LINK	Convert patterns looking like hyperlinks to actual ones <a>
HTMLSAN	Sanitizes suspicious HTML with JellyXMLSanitizer
NG	sanitizes against angular expressions
NOESC	Disables escaping for the specified string
SAFE	No JavaScript interpolation protection

HTML
	& => &
  	< => &lt;
  	> => &gt;

JS
	' => \'
  	" => \"
  	CR => blank
  	NL => \n  (the string "\n" so that javascript interprets it as a NL)
  	<script...> => &lt;script...&gt;
  	</script> => &lt;/script...&gt;
  if phase 1:
  	&  =>  &amp;
  	<  =>  \\u003C

JS_STRING
	Same as JS escaping except that less than (<) is not escaped.

NS
	Note: this is only done if glide.ui.escape_text is false.
	<script...> => &lt;script...&gt;
	</script> => &lt;/script...&gt;

JS_XML
	' => \'
  	CR => blank
  	NL => \n  (the string "\n" so that javascript interprets it as a NL)
  	<script...> => &lt;script...&gt;
  	</script> => &lt;/script...&gt;
  	< => \\u003C
  	> => \\u003E
  
  	if phase 1:
  	& => &amp;

URL
	http://localhost:8080/nav_to.do?uri=sys_ui_page.do?sys_id=zzz => http%3A%2F%2Flocalhost%3A8080%2Fnav_to.do%3Furi%3Dsys_ui_page.do%3Fsys_id%3Dzzz

NLBR
	"This\n<strong>is</strong>\na\ntest" => This<br></br>&lt;strong&gt;is&lt;/strong&gt;<br></br>a<br></br>test

WBR
	Word break, insert &lt;shy; in long sequences the browser would not break

LINK
	Convert patterns looking like hyperlinks to actual ones <a>

HTMLSAN
	Sanitizes suspicious HTML with JellyXMLSanitizer.

NG
	Sanitizes against angular expressions
	{{ => {​\\u200b{

NOESC
	No escaping

SAFE
	No JavaScript interpolation protection

Manually Sanitize output

SNC.GlideHTMLSanitizer.sanitizeWithConfig("HTMLSanitizerConfig","Your text here")

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Jelly Tags

Tag	Description
<j:if test="">...</j:if>	Execute block if test is: - a Boolean and true OR - a String and = "true", "yes", "on", or "1"
<j:while test="">...</j:while>	Repeat block until test is false
<j:set var="" value="" defaultValue="" />	Set var to value or defaultValue if value is empty
<g:set_if var="" test="" true="" false="" />	Set var to expression in true or false depending on result of test
<j:choose><j:when test=""/><j:otherwise/></j:choose>	Combination of a switch statement and if/else if statement, uses the first when block where test is true, otherwise defines the default case
<g:inline template="" />	Insert a jTemplate or UI Macro at this position with access to surrounding Jelly context
<g:insert template="" />	Similar to g:inline but can't access Jelly variables from the surrounding context
<g:evaluate var="" jelly="" copyToPhase2="">...</g:evaluate>	Evaluate code block in Rhino and assign result to var jelly = true to access jelly variables inside script copyToPhase2 = true to make var available in phase 2 context
<g:evaluate var="" expression=""/>	Same as above except self closing usage. Evaluate expression in Rhino and assign result to var
<g:no_escape>...</g:no_escape>	Disables automatic output escaping of all contained ${} expressions
<g:breakpoint var="" />	Dumps all of the current jelly variables to the debug ouput Or a single variable if specified with var

If Tag:

<j:if test="${jvar_ref}">...do something</j:if>

While tag:

<j:while test="${jexl_expression}"></j:while>

Set tag:

<j:set var="jvar_your_variable" value="${jexl_expression}" defaultValue="anything" />

Set_if tag:

<g:set_if var="jvar_your_var" test="${jexl_expression}" true="anything" false="anything" />

Choose tag:

<j:choose>
	<j:when test="${jexl_expression}">Anything</j:when>
	<j:when test="${!jexl_expression}">Anything</j:when>
	<j:when test="${jvar == 'hello'}">World</j:when>
	<j:otherwise>The default case</j:otherwise>
</j:choose>

Insert tag:

<g:insert template="some_template.xml" />

Inline tag

<g:inline template="some_template.xml" />

Evaluate tag:

<g:evaluate var="jvar_result">
	Math.random();
</g:evaluate>

jvar_result will contain the result of the evaluate tag. var = The last line of code in the evaluate block.

<g:evaluate var="jvar_result" expression="Math.random() * 100;" />

A single line usage of evaluate. Evaluates the contents of expression.

<g:evaluate var="jvar_result" expression="new Date()" object="true" />

To treat the returned evaluation as an object, set object="true". Use when returning anything other than string or int.

<g:evaluate var="jvar_msg" expression="'the cup is ' + jelly.sysparm_cup;" jelly="true" />

To use Jelly variables inside your Rhino script, set jelly="true". Any jelly variable will be accessible on the jelly object inside the code block.

<g:evaluate var="jvar_result" expression="new Date().getMinutes()" copyToPhase2="true" />

To use the result of the expression in phase 2 like this $[jvar_result], set copyToPhase2="true".

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Common System Properties

Property name	Description
glide.ui.template.trace	true = Display jelly template tracing output in log full = Include full template path in tracing output false = Disable template tracing
glide.ui.js_includes	true = Bundle JS includes into a few large files false = Load JS files separately (useful for debugging)
glide.ui.session_timeout	Session timeout in minutes
glide.ui.i18n_test	true = Adds a prefix to each translated message and field false = Off
glide.sys.date_format	Customize the system default date format
glide.sys.time_format	Customize the system default time format

Session Properties vs Database Properties

To change a property for just the current user session use:

GlideProperties.set('key', 'value');

To change a system property for everyone, and modify the sys_property table use:

gs.setProperty('key', 'value'); // You must have maint role to do this

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Common Glide Server globals

Variable	Description
action	Action handler (only available if running in a UI action)
current	Current record as GlideRecord
previous	The current record prior to any updates being applied
g_scratchpad	This object is serialized and passed to the client at the end of the transaction
gs	GlideSystem
RP	RenderProperties
ref	The table name of the current record

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Common Glide Server Scripting APIs

• JSUtil
• GlideRecord
• GlideUser (gs.getUser())
• GlideSession (gs.getSession())
• GlideProperties

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GlideSystem (gs) server scripting APIs

API	Description
.addInfoMessage(String)	Display an info message on the client.
.addErrorMessage(String)	Display an error message on the client.
.getMessage(String	Array)
.getProperty(String key, Object default)	Get a system property value or use default if not found.
.nil(Object)	Returns true if the object is null, undefined or an empty string.
.base64Encode(String)	Returns a base64 encoded string.
.base64Decode(String)	Returns an ASCII string from a base64 encoded string.
.info(String message, Object, Object, Object...)	Writes a message to the system log
.print(String)	Prints a message to the debug console
.getSession()	Returns the current glide session.
.getUser()	Returns the GlideUser of the current user.
.getUserName()	Returns the name of the current user.
.urlEncode(String)	Returns a UTF-8 encoded string.
.urlDecode(String)	Returns an ASCII string from a UTF-8 encoded string.

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