When to Use

Use this skill when:

• Creating or modifying .hbs template files

• Adding new Handlebars helpers or partials

• Debugging template rendering issues

• Understanding existing template patterns in Aurora CLI

• Working with dynamic code generation

Critical Patterns

Aurora CLI Template Engine Setup

The template engine is configured in src/@cliter/utils/template-engine.ts :

• Uses handlebars library with handlebars-helpers addon (189+ built-in helpers)

• Custom helpers are registered in src/@cliter/handlebars/helpers/

• Partials are registered in src/@cliter/handlebars/partials/

• Templates are in src/templates/ (back/, front/, pipeline/)

Important: Aurora CLI includes ALL helpers from the handlebars-helpers package automatically. These 189+ helpers are available in every template without any additional configuration.

Helper Registration Pattern

// src/@cliter/handlebars/helpers/my-helper.ts import * as handlebars from 'handlebars';

handlebars.registerHelper('myHelper', function(param1: string, param2: any, options) { // options.data.root contains all template data // options.fn(this) executes block content // options.inverse(this) executes else block return result; });

Partial Registration Pattern

// src/@cliter/handlebars/partials/my-partial.ts import * as handlebars from 'handlebars';

handlebars.registerPartial('myPartial', {{#each items}} {{ this.name }} {{/each}});

Handlebars Syntax Guide

Basic Expressions

{{! Comment - not rendered }} {{ variable }} {{! Simple output }} {{{ rawHtml }}} {{! Unescaped HTML }} {{ helper param1 param2 }} {{! Helper call }} {{ object.property }} {{! Property access }} {{ ../parentContext }} {{! Parent context access }}

Whitespace Control

{{expression}} {{! Trim whitespace before }} {{expression}} {{! Trim whitespace after }} {{expression}} {{! Trim both sides }}

Block Helpers

{{#if condition}} content if true {{else}} content if false {{/if}}

{{#each array}} {{@index}} - {{@first}} - {{@last}} - {{this}} {{/each}}

{{#unless condition}} content if false {{/unless}}

{{#with object}} {{property}} {{! Access object.property }} {{/with}}

Custom Block Helpers (Aurora CLI)

{{#loops 10}} {{@index}} {{@first}} {{@last}} {{/loops}}

{{#eq value1 value2}} content if equal {{/eq}}

{{#unlessEq value1 value2}} content if not equal {{/unlessEq}}

Aurora CLI Helper Categories

String Transformation Helpers

Helper Description Example

toCamelCase

Convert to camelCase {{ toCamelCase "my_name" }} → myName

toPascalCase

Convert to PascalCase {{ toPascalCase "my_name" }} → MyName

toKebabCase

Convert to kebab-case {{ toKebabCase "myName" }} → my-name

toSnakeCase

Convert to snake_case {{ toSnakeCase "myName" }} → my_name

sumStrings

Concatenate strings {{ sumStrings "Hello" " " "World" }}

singleLine

Remove line breaks {{ singleLine multiLineText }}

Variable Management Helpers

{{! Set a variable in root context }} {{ setVar 'myVar' 'value' }} {{ setVar 'myVar' (someHelper param) }}

{{! Use the variable }} {{ myVar }}

Array/Object Helpers

{{! Create an array }} {{ setVar 'items' (array 'item1' 'item2' 'item3') }}

{{! Create an object }} {{ setVar 'obj' (object key1='value1' key2='value2') }}

{{! Push to array }} {{ push myArray (object name='newItem') }}

{{! Check if has items }} {{#if (hasItems myArray)}} has items {{/if}}

Conditional Helpers

{{! Ternary operator }} {{ ternary condition 'trueValue' 'falseValue' }}

{{! Check if undefined }} {{#if (isUndefined variable)}} is undefined {{/if}}

{{! Not in array }} {{#if (notInArray item array)}} not in array {{/if}}

Property Filter Helpers

Most property helpers filter schema.aggregateProperties :

{{! Get properties without timestamps }} {{#each (getWithoutTimestampsProperties schema.aggregateProperties)}} {{ name }} {{/each}}

{{! Get enum properties }} {{#each (getEnumProperties schema.aggregateProperties)}} {{ name }}: {{ type }} {{/each}}

{{! Get relationship properties }} {{#each (getWithRelationshipOneToOneProperties schema.aggregateProperties)}} {{ relationship.aggregateName }} {{/each}}

Import Manager Helper

{{! Initialize imports array }} {{ setVar 'importsArray' ( array (object items=(array 'Injectable') path='@nestjs/common') (object items='MyClass' path='./my-class') ) ~}}

{{! Add more imports dynamically }} {{ push importsArray (object items='AnotherClass' path='./another') ~}}

{{! Render all imports }} {{{ importManager (object imports=importsArray) }}}

ID Generation Helpers

{{ uuid 'fieldName' }} {{! Generate deterministic UUID }} {{ nanoid 'fieldName' }} {{! Generate NanoID }} {{ randomIntegerDigits 5 }} {{! Random integer with N digits }} {{ randomDecimalDigits 2 3 }} {{! Random decimal (int.dec) }}

Handlebars-Helpers Package (Built-in)

Aurora CLI includes all 189+ helpers from the handlebars-helpers package. These are available automatically in all templates.

String Helpers (36 helpers)

{{ append "hello" " world" }} {{! "hello world" }} {{ camelcase "foo bar" }} {{! "fooBar" }} {{ capitalize "hello" }} {{! "Hello" }} {{ capitalizeAll "hello world" }} {{! "Hello World" }} {{ dashcase "fooBar" }} {{! "foo-bar" }} {{ dotcase "fooBar" }} {{! "foo.bar" }} {{ ellipsis "long text..." 10 }} {{! "long te..." }} {{ hyphenate "foo bar" }} {{! "foo-bar" }} {{ lowercase "HELLO" }} {{! "hello" }} {{ pascalcase "foo bar" }} {{! "FooBar" }} {{ pathcase "fooBar" }} {{! "foo/bar" }} {{ prepend "world" "hello " }} {{! "hello world" }} {{ remove "foobar" "bar" }} {{! "foo" }} {{ replace "foobar" "bar" "baz" }} {{! "foobaz" }} {{ reverse "abc" }} {{! "cba" }} {{ sentence "hello. world" }} {{! "Hello. World" }} {{ snakecase "fooBar" }} {{! "foo_bar" }} {{ split "a,b,c" "," }} {{! ["a","b","c"] }} {{ startsWith "hello" "he" }} {{! true }} {{ titleize "hello world" }} {{! "Hello World" }} {{ trim " hello " }} {{! "hello" }} {{ truncate "long text" 5 }} {{! "long..." }} {{ truncateWords "a b c d" 2 }} {{! "a b..." }} {{ uppercase "hello" }} {{! "HELLO" }} {{ center "text" 10 }} {{! Centers with spaces }} {{#isString value}}is string{{/isString}}

Array Helpers (28 helpers)

{{ after myArray 2 }} {{! Items after index 2 }} {{ arrayify value }} {{! Converts to array }} {{ before myArray 3 }} {{! First 3 items }} {{ first myArray }} {{! First item }} {{ first myArray 3 }} {{! First 3 items }} {{ last myArray }} {{! Last item }} {{ last myArray 2 }} {{! Last 2 items }} {{ length myArray }} {{! Array length }} {{ join myArray ", " }} {{! "a, b, c" }} {{ reverse myArray }} {{! Reversed array }} {{ sort myArray }} {{! Sorted array }} {{ sortBy myArray "name" }} {{! Sort by property }} {{ unique myArray }} {{! Remove duplicates }} {{ itemAt myArray 2 }} {{! Item at index 2 }} {{ pluck users "name" }} {{! Extract "name" from objects }} {{#inArray "a" myArray}}found{{/inArray}} {{#isArray value}}is array{{/isArray}} {{#equalsLength myArray 5}}has 5{{/equalsLength}}

{{#forEach myArray}} {{@index}} {{@first}} {{@last}} {{this}} {{/forEach}}

{{#eachIndex myArray}} {{item}} at {{index}} {{/eachIndex}}

{{#filter myArray}}{{/filter}} {{#map myArray}}{{/map}} {{#some myArray}}{{/some}} {{#withFirst myArray}}{{this}}{{/withFirst}} {{#withLast myArray 2}}{{this}}{{/withLast}} {{#withGroup myArray 3}}{{this}}{{/withGroup}} {{#withSort myArray "name"}}{{this}}{{/withSort}}

Comparison Helpers (24 helpers)

{{#and value1 value2}}both truthy{{/and}} {{#or value1 value2}}at least one truthy{{/or}} {{#not value}}falsey{{/not}} {{#eq a b}}equal{{/eq}} {{#is a b}}loosely equal{{/is}} {{#isnt a b}}not equal{{/isnt}} {{#gt a b}}greater than{{/gt}} {{#gte a b}}greater or equal{{/gte}} {{#lt a b}}less than{{/lt}} {{#lte a b}}less or equal{{/lte}} {{#compare a ">" b}}comparison{{/compare}} {{#contains collection value}}found{{/contains}} {{#has value pattern}}matches{{/has}} {{#ifEven num}}even{{/ifEven}} {{#ifOdd num}}odd{{/ifOdd}} {{#ifNth 10 2}}every 2nd{{/ifNth}} {{#isTruthy value}}truthy{{/isTruthy}} {{#isFalsey value}}falsey{{/isFalsey}} {{#neither a b}}both falsey{{/neither}} {{ default value "fallback" }} {{! Returns fallback if undefined }} {{#unlessEq a b}}not equal{{/unlessEq}} {{#unlessGt a b}}not greater{{/unlessGt}} {{#unlessLt a b}}not less{{/unlessLt}}

Math Helpers (16 helpers)

{{ abs -5 }} {{! 5 }} {{ add 1 2 }} {{! 3 }} {{ subtract 5 2 }} {{! 3 }} {{ multiply 3 4 }} {{! 12 }} {{ divide 10 2 }} {{! 5 }} {{ modulo 10 3 }} {{! 1 }} {{ ceil 4.3 }} {{! 5 }} {{ floor 4.7 }} {{! 4 }} {{ round 4.5 }} {{! 5 }} {{ avg myNumbers }} {{! Average of array }} {{ sum myNumbers }} {{! Sum of array }} {{ random 1 100 }} {{! Random between 1-100 }} {{ plus 1 2 }} {{! Alias for add }} {{ minus 5 2 }} {{! Alias for subtract }} {{ times 3 4 }} {{! Alias for multiply }} {{ remainder 10 3 }} {{! Alias for modulo }}

Number Helpers (9 helpers)

{{ bytes 1024 }} {{! "1 KB" }} {{ addCommas 1000000 }} {{! "1,000,000" }} {{ phoneNumber "1234567890" }} {{! "(123) 456-7890" }} {{ toAbbr 1000000 }} {{! "1m" }} {{ toExponential 12345 2 }} {{! "1.23e+4" }} {{ toFixed 3.14159 2 }} {{! "3.14" }} {{ toFloat "3.14" }} {{! 3.14 }} {{ toInt "42" }} {{! 42 }} {{ toPrecision 3.14159 3 }} {{! "3.14" }}

Object Helpers (14 helpers)

{{ get object "nested.path" }} {{! Get nested value }} {{ getObject object "key" }} {{! Get key-value pair }} {{ JSONstringify object }} {{! JSON string }} {{ JSONparse jsonString }} {{! Parse JSON }} {{ stringify value }} {{! String representation }} {{#hasOwn object "key"}}has key{{/hasOwn}} {{#isObject value}}is object{{/isObject}} {{#forIn object}}{{@key}}: {{this}}{{/forIn}} {{#forOwn object}}{{@key}}: {{this}}{{/forOwn}} {{#extend obj1 obj2}}{{/extend}} {{#merge obj1 obj2}}{{/merge}} {{#pick context "a" "b"}}{{/pick}} {{ toPath "a" "b" "c" }} {{! "a.b.c" }}

URL Helpers (9 helpers)

{{ encodeURI "hello world" }} {{! "hello%20world" }} {{ decodeURI "hello%20world" }} {{! "hello world" }} {{ escape value }} {{! URL escaped }} {{ urlResolve base path }} {{! Resolved URL }} {{ urlParse url }} {{! Parsed URL object }} {{ stripQuerystring url }} {{! URL without query }} {{ stripProtocol url }} {{! URL without protocol }} {{ url_encode value }} {{! Alias for encodeURI }} {{ url_decode value }} {{! Alias for decodeURI }}

Date Helpers (3 helpers)

{{ year }} {{! Current year }} {{ date }} {{! Current date }} {{ moment date "YYYY-MM-DD" }} {{! Format with moment.js }}

Path Helpers (8 helpers)

{{ basename "/a/b/file.txt" }} {{! "file.txt" }} {{ dirname "/a/b/file.txt" }} {{! "/a/b" }} {{ extname "file.txt" }} {{! ".txt" }} {{ stem "file.txt" }} {{! "file" }} {{ resolve "a" "b" "c" }} {{! Absolute path }} {{ relative "/a/b" "/a/c" }} {{! "../c" }} {{ segments path 0 2 }} {{! Path segments range }} {{ absolute path 1 }} {{! Directory segment }}

Collection Helpers (2 helpers)

{{#isEmpty collection}}empty{{/isEmpty}} {{#iterate collection}}{{this}}{{/iterate}}

Inflection Helpers (2 helpers)

{{ inflect count "item" "items" }} {{! Pluralization }} {{ ordinalize 1 }} {{! "1st" }} {{ ordinalize 22 }} {{! "22nd" }}

Regex Helpers (2 helpers)

{{ toRegex "pattern" "gi" }} {{! Creates RegExp }} {{#test "hello" "ell"}}matches{{/test}}

HTML Helpers (7 helpers)

{{ sanitize "<b>text</b>" }} {{! "text" }} {{{ ul myArray }}} {{! <ul><li>...</li></ul> }} {{{ ol myArray }}} {{! <ol><li>...</li></ol> }} {{{ css "styles.css" }}} {{! <link rel="stylesheet"...> }} {{{ js "script.js" }}} {{! <script src="..."></script> }} {{ attr attributes }} {{! Stringifies HTML attributes }} {{ thumbnailImage image }} {{! Figure with thumbnail }}

Markdown Helpers (2 helpers)

{{{ markdown "bold" }}} {{! <strong>bold</strong> }} {{{ md "./file.md" }}} {{! Rendered markdown file }}

Misc Helpers (5 helpers)

{{ typeOf value }} {{! "string", "array", etc. }} {{ noop }} {{! Renders block without processing }} {{ option "key" }} {{! Get value from options }} {{#withHash key="value"}}{{key}}{{/withHash}} {{ frame }} {{! Frame-related helper }}

Logging Helpers (11 helpers)

{{ log "message" }} {{! Console log }} {{ info "info message" }} {{! Info level }} {{ warn "warning" }} {{! Warning level }} {{ error "error" }} {{! Error level }} {{ success "done" }} {{! Success message }} {{ ok "ok" }} {{! Ok message }} {{ danger "danger" }} {{! Danger message }} {{ bold "text" }} {{! Bold formatting }} {{ _debug value }} {{! Debug output }} {{ _inspect value }} {{! Inspect value }}

Full Reference: See references/handlebars-helpers-reference.md for complete documentation.

Decision Tree

Need string transformation? → toCamelCase, toPascalCase, toKebabCase, toSnakeCase (Aurora) → camelcase, pascalcase, snakecase, dashcase (handlebars-helpers) Need to store temporary data? → setVar Need to build arrays/objects? → array, object, push Need conditional rendering? → if, unless, eq, unlessEq, ternary, and, or, not, compare Need to iterate? → each, loops, forEach, eachIndex, forIn, forOwn Need to filter properties? → get*Properties helpers (Aurora custom) Need to manage imports? → importManager with importsArray Need unique IDs? → uuid, nanoid Need math operations? → add, subtract, multiply, divide, ceil, floor, round Need string manipulation? → trim, split, replace, truncate, append, prepend Need array operations? → first, last, sort, unique, filter, map, join Need object access? → get, hasOwn, forIn, forOwn Need URL handling? → encodeURI, decodeURI, urlParse, stripQuerystring Need path operations? → basename, dirname, extname, resolve

Code Examples

Example 1: Creating a New Helper

// src/@cliter/handlebars/helpers/is-required-property.ts import * as handlebars from 'handlebars'; import { Property } from '../../types';

handlebars.registerHelper('isRequiredProperty', function( property: Property, ) { return !property.nullable && !property.hasOwnProperty('defaultValue'); });

Example 2: Using Multiple Helpers in Template

{{! Generate TypeScript interface }} export interface {{ toPascalCase schema.moduleName }}Input { {{#each (getWithoutTimestampsProperties schema.aggregateProperties)}} {{ toCamelCase name }}{{#if nullable}}?{{/if}}: {{ getDtoTypeProperty this ../config }}; {{/each}} }

Example 3: Complex Import Management

{{ setVar 'importsArray' ( array (object items=(array 'Injectable' 'Inject') path='@nestjs/common') ) ~}} {{#each (getEnumProperties schema.aggregateProperties)}} {{ push ../importsArray (object items=(toPascalCase name) path='@api/graphql') ~}} {{/each}} {{{ importManager (object imports=importsArray) }}}

Example 4: Conditional Blocks with Context

{{#each (getDtoProperties schema.aggregateProperties)}} {{#if (isAllowProperty ../schema.moduleName this)}} {{#eq type ../propertyType.ENUM}} // Handle enum type {{ toPascalCase ../schema.moduleName }}{{ toPascalCase name }} {{else}} // Handle other types {{ getDtoTypeProperty this ../config }} {{/eq}} {{/if}} {{/each}}

Commands

Build after adding helpers

yarn build

Find all helpers

ls src/@cliter/handlebars/helpers/

Find helper usage in templates

grep -r "helperName" src/templates/

Test template rendering

yarn test

Common Mistakes to Avoid

Missing whitespace control: Use ~ to trim unwanted whitespace

{{! Bad - adds extra lines }} {{#if condition}} content {{/if}}

{{! Good - clean output }} {{#if condition}} content {{/if}}

Wrong context access: Use ../ to access parent context in loops

{{#each items}} {{ ../schema.moduleName }} {{! Access parent, not current item }} {{/each}}

Forgetting to register helper: Add import in src/@cliter/handlebars/helpers/index.ts

Using {{ instead of {{{ : For HTML/code output, use triple braces to avoid escaping

Resources

• Templates: See assets/ for helper and partial templates

• Aurora Helpers: See references/helpers-reference.md for Aurora CLI custom helpers

• Built-in Helpers: See references/handlebars-helpers-reference.md for handlebars-helpers package

• GitHub: https://github.com/helpers/handlebars-helpers