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A Generator generates a value that will be used in a request. Most Generators produce a different value each time they are used to construct a request.

Generators may be specified for fields of a request in Generator Rules in the configuration, or used as functions in templates (e.g., see generator OneOfJSON). In either case, a Generator produces a single value of type boolean, number, string, object, or array.

In the web UI, Generators are configured in the API Settings, which in turn affects the Sift configuration for a test run.

Generator Parameters

Some generators require parameter values to be given. In the table below, the parameters are described as named function parameters, such as:

(min int, max int)

When using a Generator in a template (e.g., for OneOfJSON), the parameters are passed as function arguments, such as:

{{ IntRange 2 7 }}

where min=2 and max=7.

When using a Generator in a Generator Rule, parameters are expressed as key-value pairs. Use the parameter name as the key. For example:

  min: 2
  max: 7

Available Generators

Various kinds of Generators are available in Sift, as described in the following table.

Name Parameters Description
Boolean - Generates a true or false boolean value.
DateTime - Generates a timestamp for the current UTC time. The string is formatted according to Internet Date/Time Format defined in RFC 3339, Section 5.6 which is a profile of ISO8601.
IntRange (min int, max int) Generates an integer in a specified range.
IntConstant (value int) Generates a fixed integer every time.
OneOfJSON (options []string)
Chooses one random element from an array of strings that are each a text represention of a JSON element. A value is generated by parsing the chosen JSON element string into a boolean, number, string, object, or array value. The JSON element string may include template syntax to construct the element string. Within a template expression, other Generators may be called as functions to produce dynamic elements. Template expressions are wrapped inside of {{ }}.
For example, the JSON value {"name": {{ Regex "[a-z]{5}" }}, "quantity": {{ IntRange 4 9 }}} will generate an object with a key "name" that has a string value of five lower-case characters and a key "quantity" which has a number value between 4 and 9 (inclusive). The generated value used in a request may look like {"name": "afjix", "number": 8 }.
Regex (expr string) Generates a random string that matches a given regular expression.
ResourceReference (resource string) Generates an identifier that refers to a resource instance of the kind of specified in the resource parameter. This generator defines a dependency relationship between the operation that contains the field for which the generator is configured and another operation that can create or list the given kind of resource. This dependency relationship affects the sequences of operations that are generated, so that a valid resource identifier may first be obtained.
StringConstant (value string) Generates a fixed string every time.
Email - Generates an email address.
Username - Generates a username of 3-30 alphanumeric and underscore characters.
Password - Generates a password with at least one uppercase letter, one lowercase letter, one digit, one special character, and at least 9 characters in length.
URL - Generates a URL.
Domain - Generates a domain name.
IPv4 - Generates an IPv4 address.
IPv6 - Generates an IPv6 address.
MAC - Generates a MAC address.
DateISO8601 - Generates a random date in the ISO 8601 format (YYYY-MM-DD).
DateMMDDYYYY - Generates a random date in MM/DD/YYYY format.
DateDDMMYYYY - Generates a random date in DD/MM/YYYY format.
DateYYYYMMDD - Generates a random date in YYYY/MM/DD format.
TimestampISO8601 - Generates a random timestamp that includes a combined date and time in ISO 8601 format.
Time24Hour - Generates a random time in 24-hour format (hh:mm).
Time12Hour - Generates a random time in 12-hour format (hh:mm AM/PM).
UUID - Generates a UUID (version 1-5).
Base64 - Generates a Base64-encoded string.
Percentage - Generates a percentage value with optional decimal places.
Currency - Generates a currency value with optional decimal places.
CurrencyCode - Generates a three-letter currency code.
CreditCard - Generates a phony credit card number.
CVV - Generates a credit card CVV (3 or 4 digits).
SSN - Generates a random US Social Security Number (SSN).
UKNationalInsuranceNumber - Generates a random UK National Insurance Number.
CanadianSIN - Generates a random Canadian Social Insurance Number (SIN).
DUNS - Generates a random 9-digit DUNS number.
EIN - Generates a random U.S. Federal Tax Identification Number (EIN).
IBAN - Generates a random International Bank Account Number (IBAN).
ISBN - Generates a random International Standard Book Number (ISBN). Check digit may be incorrect.
ASIN - Generates an Amazon Standard Identification Number (ASIN).
VAT - Generates a random European Union VAT number
VIN - Validates a random Vehicle Identification Number (VIN)
LicensePlate - Generates a random license plate (alphanumeric, hyphen-separated, 1-10 characters)
Slug - Generates a URL slug (lowercase, alphanumeric, hyphen-separated).
FileExtension - Generates a random file extension (1-5 alphanumeric characters)
TwitterUsername - Generates a random Twitter username
YouTubeVideoID - Generates a random YouTube video ID.
GitHubRepository - Generates a random GitHub repository path
PhoneNumber - Generates a phone number with optional international prefix.
PhoneExtension - Generates a phone extension (1 to 5 digits).
StreetAddress - Generates a random street address.
CountryCode - Generates a two-letter country code.
PostalCodeUS - Generates a US ZIP code (5 or 9 digits).
PostalCodeCanada - Generates a Canadian postal code.
PostalCodeAustralia - Generates an Australian postal code.
PostalCodeIndia - Generates an Indian postal code.
PostalCodeBrazil - Generates a Brazilian postal code (CEP).
PostalCodeUK - Generates a UK postcode.
PostalCodeFrance - Generates a French postal code.
PostalCodeGermany - Generates a German postal code.
PostalCodeItaly - Generates an Italian postal code.
PostalCodeSpain - Generates a Spanish postal code.
Latitude - Generates a latitude coordinate.
Longitude - Generates a longitude coordinate.
MIMEType - Generates a random MIME type.
HTMLTag - Generates an HTML tag.
ColorHex - Generates a 3- or 6-digit hexadecimal color code.
ColorRGB - Generates an RGB color value.
ColorRGBA - Generates an RGBA color value.
ColorHSL - Generates an HSL color value.