test data generation tool

[kortemik]

Description
create command with ability to generate data over multiple batches and possibly infinite amount of it.

Use case or motivation behind the feature request
| makeresults is inferior to teragrep testing requirements. it can not generate sequence of data and it can not generate data over multiple batches. this means that a separate command with such functionality would make possible more rigorous testing and demoing of the product.

Related issues

Additional context

[kortemik]

| teragrep exec datagen [count=] [batchsize=] [loop=] [timestart=]

generates sequence of events, starting from _raw=0 _time=0 (1970) if count not specified, amount is infinite, batchsize defaults to 25, loop restarts the sequence from 0 again same for _time. timestart takes epoch and secifies the 0 point of time.

[elliVM]

adding option for named columns would be useful for testing commands that expect columns that are not present in the default schema.
a column "tokens" values between 10-1000 for example would be: fields=[tokens:random(10-1000)] etc.

[kortemik]

adding option for named columns would be useful for testing commands that expect columns that are not present in the default schema. a column "tokens" values between 10-1000 for example would be: fields=[tokens:random(10-1000)] etc.

i think we could run | eval tokens=random() to allow such