Moldova

Moldova is a lightweight template interpreter, used to generate random values that plug into the template, as defined by a series of custom tokens.

It understands the tokens as defined further down in the document.

Moldova comes both as a library you can import, as well as a binary executable that you can run, which will output results to STDOUT.

The intended use is via the binary executable.

Works great with the Slammer

Moldova was originally designed as input to a database load testing tool, called the Slammer. It's primary purpose was to generate INSERT and SELECT statements, which were then loaded into the Slammer. If you're looking for a good tool to test the throughput and latency of database operations at scale, checkout the Slammer.

And if you're interested in using them together, checkout the Moldovan Slammer, a quick helper repo to demonstrate using them together

Moldova command

To use the command, first install

go install github.com/StabbyCutyou/moldova/cmd/moldova

The command accepts 2 arguments:

• n - How many templates to render to STDOUT. The default is 1, and it cannot be less than 1.
• t - The template to render

Example

moldova -t "INSERT INTO floof VALUES ('{guid}','{guid:ordinal:0}','{country}',{int:min:-2000|max:0},{int:min:100|max:1000},{float:min:-1000.0|max:-540.0},{int:min:1|max:40},'{now}','{now:ordinal:0}','{country:case:up}',NULL,-3)" -n 100

This would provide sample output like the following:

...
INSERT INTO floof VALUES ('791add99-43df-44c8-8251-6f7af7a014df','791add99-43df-44c8-8251-6f7af7a014df','MU',-1540,392,-624.529332,39,'2016-01-24 23:42:49','2016-01-24 23:42:49','UN',NULL,-3)
INSERT INTO floof VALUES ('0ab4cc33-6689-404f-a801-4fd431ca3f30','0ab4cc33-6689-404f-a801-4fd431ca3f30','PL',-1707,112,-550.333145,1,'2016-01-24 23:42:49','2016-01-24 23:42:49','SS',NULL,-3)
INSERT INTO floof VALUES ('a3f4151a-a304-4190-a3df-7fd97ce58588','a3f4151a-a304-4190-a3df-7fd97ce58588','CM',-1755,569,-961.122173,25,'2016-01-24 23:42:49','2016-01-24 23:42:49','NE',NULL,-3)

Tokens

Tokens are represented by special values placed inside of { } characters.

Each token follows this pattern:

{command:argument_name:value|argument_name:value|...|...}

Each token defines it's own set of arguments, which are outlined below. If you're provided multiple arguments, the key-value pairs of argument names to values are delimited by a | pipe character. These can be provided in any order, so long as they are valid arguments.

It is only necessary to provide a | when you have further arguments to provide. For example:

• {int}
• {int:min:10}
• {int:min:10|max:50}
• {int:min:10|max:50|ordinal:0}

{guid}

Options

• ordinal : integer >= 0

Description

Moldova will replace any instance of {guid} with a GUID/UUID

If you provide the ordinal: option, for the current line of text being generated, you can have Moldova insert an existing value, rather than a new one. For example:

"{guid} - {guid:ordinal:0}"

In this example, both guids will be replaced with the same value. This is a way to back-reference existing generated values, for when you need something repeated.

{now}

Options

• format : string, either "simple", "simpletz", or a golang date format string
• ordinal : integer >= 0
• zone: A timezone to represent the time in. You can use any value accepted here

Description

Moldova will replace any instance of {now} with a string representation of Golangs time.Now() function, formatted per the provided date format. There are 2 built in formats, for convenience, that are compatible with many databases.

• simple - "2006-01-02 15:04:05"
• simpletz - "2006-01-02 15:04:05 -0700"

Additionally, you can provide your own format string.

{now} also supports the ordinal: option

{time}

Options

• min : integer < max, unix epoch value
• max : integer > min, unix epoch value
• format : string, either "simple", "simpletz", or a golang date format string
• ordinal : integer >= 0
• zone: A timezone to represent the time in. You can use any value accepted here

Description

Moldova will replace any instance of {time} with a string representation of a random time, between min and max in terms of Unix Epoch values. The defaults are between 0, and roughly Now (determined at runtime) There are 2 built in formats, for convenience, that are compatible with many databases.

• simple - "2006-01-02 15:04:05"
• simpletz - "2006-01-02 15:04:05 -0700"

Additionally, you can provide your own format string.

{time} also supports the ordinal: option

{int}

Options

• min : integer < max
• max : integer > min
• ordinal : integer >= 0

Description

Moldova will replace any instance of {int} with a random int value, optionally between the range provided. The defaults, if not provided, are 0 to 100.

{int} also supports ordinal: option

{float}

Options

• min : integer < max
• max : integer > min
• ordinal : integer >= 0

Description

Moldova will replace any instance of {float} with a random Float64, optionally between the range provided. The defaults, if not provided, are 0.0 to 100.0

{float} also supports ordinal: option

{unicode}

Options

• length : integer >= 1
• case : "up" or "down"
• ordinal : integer >= 0

Description

Moldova will replace any instance of {unicode} with a randomly generated set of unicode characters, of a length specified by :number. The default value is 2.

{unicode} also takes the :case argument, which is either 'up' or 'down', like so

{unicode:case:up} {unicode:case:down}

{unicode} also supports ordinal: option

Only a certain subset of unicode character ranges are supported by default, as defined in the moldova/data/unicode.go file.

{ascii}

Options

• length : integer >= 1
• case : "up" or "down"
• ordinal : integer >= 0

Description

Moldova will replace any instance of {ascii} with a randomly generated set of ASCII characters, of a length specified by :number. The default value is 2.

{ascii} also takes the :case argument, which is either 'up' or 'down', like so

{ascii:case:up} {ascii:case:down}

{ascii} also supports ordinal: option

{firstname}

Options

• language : any string value
• case : "up" or "down"
• ordinal : integer >= 0

Description

Moldova will replace any instance of {firstname} with a randomly generated first name, from the list defined in data/names.go

{firstname} takes a :langage argument, which can be any of the supported language strings in data/names.go. If the chosen name does not have an entry for the selected language, the configured default will be used in it's place. For exmaple:

{firstname:language:romanian}

{firstname} also takes the :case argument, which is either 'up' or 'down', like so

{firstname:case:up} {firstname:case:down}

{firstname} also supports :ordinal option

Only a certain subset of unicode character ranges are supported by default, as defined in the moldova/data/unicode.go file.

{lastname}

Options

• language : any string value
• case : "up" or "down"
• ordinal : integer >= 0

Description

Moldova will replace any instance of {firstname} with a randomly generated first name, from the list defined in data/names.go

{lastname} takes a :langage argument, which can be any of the supported language strings in data/names.go. If the chosen name does not have an entry for the selected language, the configured default will be used in it's place. For example:

{lastname:language:romanian}

{lastname} also takes the :case argument, which is either 'up' or 'down', like so

{lastname:case:up} {lastname:case:down}

{lastname} also supports :ordinal option

Only a certain subset of unicode character ranges are supported by default, as defined in the moldova/data/unicode.go file.

{country}

Options

• case : "up" or "down"
• ordinal : integer >= 0

Description

Moldova will replace any instance of {country} with an ISO 3166-1 alpha-2 country code.

{country} supports the same case: argument as {unicode}. The default value is "up"

{country} also supports the ordinal: argument.

Roadmap

I'll continue to add support for more random value categories. There are also hooks to support ascii-only string generation, but as of yet it is not implemented.

Add proper support for escaping control characters, so they are not interpreted as part of a token. These characters are {, }, :, and |.

License

Apache v2 - See LICENSE