Templating

Template in OpenAF uses the HandleBars javascript library which has very good documentation. Nevertheless here is a collection of tricks that might be useful and most used helpers.

Name	Expression	Description
Escaping content	`{{{text}}}`	Without three braces HandleBars will replace ‘&’ with the HTML escape sequence as well as other characters.
Escaping expression	`\{{something}}`	To escape a HandleBars expression just add ´\´ before the first character
Accessing an element of an array	`{{lst.[0]}}`	Accessing a position of a provided array.
Accessing an object property with symbols	`{{obj.[something else].[item-name]}}`	To access any object property with a space or other symbols use ‘[]’.
Accessing a property from a different level	`{{#each list}}Name = {{name}}, Company = {{../company}}\n{{/each}}`	Consider the following map = `{ company: "myC", list: [ { name: "john", name: "anne" } ]}`. You can access “parent” levels as if they were a folder hierarchy (e.g. concatenating “../” as needed)
Using helpers within helpers	`{{$f '%20s' ($env 'LANG')}}`	The first helper ‘$env’ will run retrieving the current value for the environment variable ‘LANG’ and the result is used by the second helper, ‘$f’, that will format the resulting string in a right-justified line with 20 characters long (‘%20s’)

OpenAF helpers

In some cases it might be necessary to load them using ow.loadTemplate().addOpenAFHelpers()before using them.

Helper	Example	Description
$$	`{{$$ aProperty aDefaultValue}}`	Outputs the value of aProperty or, if not defined, returns the defaultValue.
$debug	`{{$debug __flags}}`	The same as stringifyInLine for the provided argument.
$stringify	`{{{$stringify __flags}}}`	Given a map will output the stringify version of it.
$stringifyInLine	`{{{$stringifyInLine __flags}}}`	Given a map will output the stringify version without new-lines.
$toYAML	`{{$toYAML __flags}}`	Given a map will output the YAML version of it.
$env	`{{$env 'PATH'}}`	Given an environment variable will output the corresponding value.
$escape	`{{{$escape aString}}}`	Given a string value will return the escaped version of it.
$f	`[{{$f '%20s' aString}}]`	Performs a $f operation with the provider parameter for the provided aString.
$ft	`[{{$ft '%20s' aString}}]`	Performs a $ft operation with the provider parameter for the provided aString.
$path	`{{$path '@' anArray}}`	Executes the function $path over the provided element.
$toSLON	`{{$toSLON aMap}}`	Given a map will output the SLON version of it.
$get	`{{$get 'res'}}`	Performs the equivalent operation to OpenAF’s $get.
$getObj	`{{$getObj 'res' 'elements'}}`	Performs the equivalent operation to OpenAF’s $get and applies the function $path using the second parameter.
$dateDiff	`{{$dateDiff aDate 'days'}}`	Given aDate will output the time difference (using the third optional argument (seconds (default), minutes, hours, days, months, weeks or years))
$switch, $case, $default	`{{#$switch value}}{{#$case 'a'}}value a{{/$case}}{{$default 'no value'}}{{/$switch}}`	Implements a switch function with case and default helpers.

Conditional helpers

In some cases it might be necessary to load them using ow.loadTemplate().addConditionalHelpers()before using them.

The conditional helpers included mimic the ones provided by Assemble for comparison

Helper	Example
`{{#isnt}}`	`{{#isnt number 5}}Kiss my shiny metal ass!{{else}}Never mind :({{/isnt}}`
`{{#and}}`	`{{#and great magnificent}}Kiss my shiny metal ass!{{else}}Never mind :({{/and}}`
`{{#contains}}`	`{{#contains truth "best"}}Absolutely true.{{else}}This is a lie.{{/contains}}`
`{{#gt}}`	`{{#gt number 8}}Kiss my shiny metal ass!{{else}}Never mind :({{/gt}}`
`{{#gte}}`	`{{#gte number 8}}Kiss my shiny metal ass!{{else}}Never mind :({{/gte}}`
`{{#if_gt}}`	`{{#if_gt x compare=y}} ... {{/if_gt}}`
`{{#if_gteq}}`	`{{#if_gteq x compare=y}} ... {{/if_gteq}}`
`{{#is}}`	`{{#is x compare=y}} ... {{/is}}`
`{{#ifeq}}`	`{{#ifeq x compare=y}} ... {{/ifeq}}`
`{{#compare}}`	`{{#compare [leftvalue ] [operator ] [rightvalue ]}}foo{{else }}bar{{/compare }}`
`{{#lt}}`	`{{#lt number 3}} ... {{else}} {{/lt}}`
`{{#lte}}`	`{{#lte number 3}} ... {{else}} {{/lte}}`
`{{#or}}`	`{{#or great magnificent}}Kiss my shiny metal ass!{{else}}Never mind :({{/or}}`
`{{#unless_eq}}`	`{{#unless_eq x compare=y}} ... {{/unless_eq}}`
`{{#unless_gt}}`	`{{#unless_gt x compare=y}} ... {{/unless_gt}}`
`{{#unless_gteq}}`	`{{#unless_gteq x compare=y}} ... {{/unless_gteq}}`
`{{#unless_lt}}`	`{{#unless_lt x compare=y}} ... {{/unless_lt}}`
`{{#unless_lteq}}`	`{{#unless_lteq x compare=y}} ... {{/unless_lteq}}`

Format helpers

In some cases it might be necessary to load them using ow.loadTemplate().addFormatHelpers()before using them.

The format helpers are all the ow.format.* functions available. For example:

templify("")
// 9.77 MB
templify("")
// 1111011

Adding a helper

Example of adding a simple template helper:

ow.template.addHelper("publicip", (aIP, aElement) => $$(ow.loadNet().getPublicIP(aIP)).get(aElement) )

templify("{{ip}} is in {{publicip ip 'country'}}", { ip: "1.1.1.1" })
// 1.1.1.1 is in Australia