Variables
HarborClient supports dynamic variables — Postman-compatible placeholders whose values are generated fresh each time a request is sent. Use them in {{$name}} syntax in:
- Request URLs
- Headers and query params
- Request body
- Auth fields
Dynamic variable names are case-sensitive and include the leading $. Each placeholder resolves to a new value on every send. The set is backed by @faker-js/faker for randomized sample data.
Static vs dynamic variables
Collection and environment variables use {{key}} syntax without a $ prefix. You define the key and value yourself in collection or environment settings.
Dynamic variables use {{$name}} syntax. HarborClient generates the value at send time — you do not store it in a variable table.
Static variables take precedence. If you define a collection or environment variable with the same key as a dynamic variable (for example $randomInt), the static value is used instead. See Environments for merge order and precedence.
Using dynamic variables in scripts
In pre- and post-request scripts, use hc.request.variables.replaceIn() to resolve placeholders in a string. See Request scripts for the full API.
javascript
hc.request.url = hc.request.variables.replaceIn('https://api.example.com/users/{{$guid}}');
console.log(hc.request.variables.replaceIn('Email: {{$randomEmail}}'));Variable filters
After HarborClient resolves a {{key}} (or {{$dynamic}}) value, you can pipe it through Twig-style filters to transform the string in place—without a pre-request script:
{{name|upper}}
{{name|trim|upper}}
{{ q | urlencode }}Filters apply left to right. Spaces around the key and pipes are optional. In the request editor, typing | inside {{ }} autocompletes registered filter names.
Unknown filter names leave the original {{…}} token unchanged in the outgoing request. Filters take the piped string only—argument support is reserved for later. The same pipeline runs at send time and in hc.request.variables.replaceIn().
| Filter | Description | Example |
|---|---|---|
upper | Uppercases the entire string. | hello → HELLO |
lower | Lowercases the entire string. | HELLO → hello |
capitalize | Uppercases the first character and lowercases the rest. | hELLO → Hello |
trim | Removes leading and trailing whitespace. | " hello " → hello |
urlencode | Percent-encodes the value (same idea as encodeURIComponent). | a b&c → a%20b%26c |
length | Returns the string length as a decimal string. | hello → 5 |
striptags | Removes HTML tags, leaving the text content. | <p>hello</p> → hello |
round | Rounds a numeric string to the nearest integer. Non-numeric values pass through unchanged. | 3.7 → 4 |
Dynamic variable reference
Common
| Variable | Description |
|---|---|
{{$guid}} | A uuid-v4 style guid |
{{$timestamp}} | The current UNIX timestamp in seconds |
{{$isoTimestamp}} | The current ISO timestamp at zero UTC |
{{$randomUUID}} | A random 36-character UUID |
Text, numbers, and colors
| Variable | Description |
|---|---|
{{$randomAlphaNumeric}} | A random alpha-numeric character |
{{$randomBoolean}} | A random boolean value |
{{$randomInt}} | A random integer between 0 and 1000 |
{{$randomColor}} | A random color name |
{{$randomHexColor}} | A random hex color value |
{{$randomAbbreviation}} | A random abbreviation |
Internet and IP addresses
| Variable | Description |
|---|---|
{{$randomIP}} | A random IPv4 address |
{{$randomIPV6}} | A random IPv6 address |
{{$randomMACAddress}} | A random MAC address |
{{$randomPassword}} | A random 15-character alpha-numeric password |
{{$randomLocale}} | A random two-letter language code (ISO 639-1) |
{{$randomUserAgent}} | A random user agent string |
{{$randomProtocol}} | A random internet protocol |
{{$randomSemver}} | A random semantic version number |
Names
| Variable | Description |
|---|---|
{{$randomFirstName}} | A random first name |
{{$randomLastName}} | A random last name |
{{$randomFullName}} | A random first and last name |
{{$randomNamePrefix}} | A random name prefix |
{{$randomNameSuffix}} | A random name suffix |
Profession
| Variable | Description |
|---|---|
{{$randomJobArea}} | A random job area |
{{$randomJobDescriptor}} | A random job descriptor |
{{$randomJobTitle}} | A random job title |
{{$randomJobType}} | A random job type |
Phone, address, and location
| Variable | Description |
|---|---|
{{$randomPhoneNumber}} | A random ten-digit phone number |
{{$randomPhoneNumberExt}} | A random phone number with extension |
{{$randomCity}} | A random city name |
{{$randomStreetName}} | A random street name |
{{$randomStreetAddress}} | A random street address |
{{$randomCountry}} | A random country name |
{{$randomCountryCode}} | A random two-letter country code (ISO 3166-1 alpha-2) |
{{$randomLatitude}} | A random latitude coordinate |
{{$randomLongitude}} | A random longitude coordinate |
Images
| Variable | Description |
|---|---|
{{$randomAvatarImage}} | A random avatar image URL |
{{$randomImageUrl}} | A URL of a random image |
{{$randomAbstractImage}} | A URL of a random abstract image |
{{$randomAnimalsImage}} | A URL of a random animal image |
{{$randomBusinessImage}} | A URL of a random stock business image |
{{$randomCatsImage}} | A URL of a random cat image |
{{$randomCityImage}} | A URL of a random city image |
{{$randomFoodImage}} | A URL of a random food image |
{{$randomNightlifeImage}} | A URL of a random nightlife image |
{{$randomFashionImage}} | A URL of a random fashion image |
{{$randomPeopleImage}} | A URL of a random image of a person |
{{$randomNatureImage}} | A URL of a random nature image |
{{$randomSportsImage}} | A URL of a random sports image |
{{$randomTransportImage}} | A URL of a random transportation image |
{{$randomImageDataUri}} | A random image data URI |
Finance
| Variable | Description |
|---|---|
{{$randomBankAccount}} | A random 8-digit bank account number |
{{$randomBankAccountName}} | A random bank account name |
{{$randomCreditCardMask}} | A random masked credit card number (last four digits) |
{{$randomBankAccountBic}} | A random BIC (Bank Identifier Code) |
{{$randomBankAccountIban}} | A random IBAN (International Bank Account Number) |
{{$randomTransactionType}} | A random transaction type |
{{$randomCurrencyCode}} | A random 3-letter currency code (ISO-4217) |
{{$randomCurrencyName}} | A random currency name |
{{$randomCurrencySymbol}} | A random currency symbol |
{{$randomBitcoin}} | A random bitcoin address |
Business
| Variable | Description |
|---|---|
{{$randomCompanyName}} | A random company name |
{{$randomCompanySuffix}} | A random company suffix |
{{$randomBs}} | A random phrase of business-speak |
{{$randomBsAdjective}} | A random business-speak adjective |
{{$randomBsBuzz}} | A random business-speak buzzword |
{{$randomBsNoun}} | A random business-speak noun |
Catchphrases
| Variable | Description |
|---|---|
{{$randomCatchPhrase}} | A random catchphrase |
{{$randomCatchPhraseAdjective}} | A random catchphrase adjective |
{{$randomCatchPhraseDescriptor}} | A random catchphrase descriptor |
{{$randomCatchPhraseNoun}} | A random catchphrase noun |
Databases
| Variable | Description |
|---|---|
{{$randomDatabaseColumn}} | A random database column name |
{{$randomDatabaseType}} | A random database type |
{{$randomDatabaseCollation}} | A random database collation |
{{$randomDatabaseEngine}} | A random database engine |
Dates
| Variable | Description |
|---|---|
{{$randomDateFuture}} | A random future datetime |
{{$randomDatePast}} | A random past datetime |
{{$randomDateRecent}} | A random recent datetime |
{{$randomWeekday}} | A random weekday name |
{{$randomMonth}} | A random month name |
Domains, emails, and usernames
| Variable | Description |
|---|---|
{{$randomDomainName}} | A random domain name |
{{$randomDomainSuffix}} | A random domain suffix |
{{$randomDomainWord}} | A random unqualified domain name |
{{$randomEmail}} | A random email address |
{{$randomExampleEmail}} | A random email address from an example domain |
{{$randomUserName}} | A random username |
{{$randomUrl}} | A random URL |
Files and directories
| Variable | Description |
|---|---|
{{$randomFileName}} | A random file name |
{{$randomFileType}} | A random file type |
{{$randomFileExt}} | A random file extension |
{{$randomCommonFileName}} | A random common file name |
{{$randomCommonFileType}} | A random common file type |
{{$randomCommonFileExt}} | A random common file extension |
{{$randomFilePath}} | A random file path |
{{$randomDirectoryPath}} | A random directory path |
{{$randomMimeType}} | A random MIME type |
Stores
| Variable | Description |
|---|---|
{{$randomPrice}} | A random price between 0.00 and 1000.00 |
{{$randomProduct}} | A random product name |
{{$randomProductAdjective}} | A random product adjective |
{{$randomProductMaterial}} | A random product material |
{{$randomProductName}} | A random product name with adjective and material |
{{$randomDepartment}} | A random commerce category |
Grammar
| Variable | Description |
|---|---|
{{$randomNoun}} | A random noun |
{{$randomVerb}} | A random verb |
{{$randomIngverb}} | A random verb ending in -ing |
{{$randomAdjective}} | A random adjective |
{{$randomWord}} | A random word |
{{$randomWords}} | Some random words |
{{$randomPhrase}} | A random phrase |
Lorem ipsum
| Variable | Description |
|---|---|
{{$randomLoremWord}} | A random word of lorem ipsum text |
{{$randomLoremWords}} | Some random words of lorem ipsum text |
{{$randomLoremSentence}} | A random sentence of lorem ipsum text |
{{$randomLoremSentences}} | A random 2 to 6 sentences of lorem ipsum text |
{{$randomLoremParagraph}} | A random paragraph of lorem ipsum text |
{{$randomLoremParagraphs}} | Three random paragraphs of lorem ipsum text |
{{$randomLoremText}} | A random amount of lorem ipsum text |
{{$randomLoremSlug}} | A random lorem ipsum URL slug |
{{$randomLoremLines}} | 1 to 5 random lines of lorem ipsum text |
Notes
- Values are generated when the request runs, not when you type the placeholder.
- Unknown
{{$name}}tokens that are not in this list are left unchanged in the outgoing request. - Image URL variables return placeholder image URLs suitable for mock requests.