[C++] Improve configurability of random data generation

[asfimport]

arrow::random::RandomArrayGenerator is useful for stress testing and benchmarking. Arrays of primitives can be generated with little boilerplate, however it is cumbersome to specify creation of nested arrays or record batches which are necessary for testing $n column operations such as group_by.

My ideal API for random generation takes only a FieldVector, a number of rows, and a seed as arguments. Other options (such as minimum, maximum, unique count, null probability, etc) are specified using field metadata so that they can be provided uniformly or granularly as necessary for a given test case:

auto random_batch = Generate({
  field("i32", int32()), // i32 may take any value between INT_MAX and INT_MIN
                         // and will be null with default probability 0.01
  field("f32", float32(), false), // f32 will be entirely valid
  field("probability", float64(), true, key_value_metadata({
    // custom random generation properties:
    {"min", "0.0"},
    {"max", "1.0"},
    {"null_probability", "0.0001"},
  }),
  field("list_i32", list(
    field("item", int32(), true, key_value_metadata({
      // custom random generation properties can also be specified for nested fields:
      {"min", "0"},
      {"max", "1"},
    })
  )),
}, num_rows, 0xdeadbeef);

Reporter: Ben Kietzman / @bkietz
Assignee: Ben Kietzman / @bkietz

Related issues:

• [C++] Improve configurability of RandomArrayGenerator::ArrayOf (supercedes)
• [C++] Add tests for RandomArrayGenerator (supercedes)

PRs and other links:

• GitHub Pull Request #9715

_{Note: This issue was originally created as ARROW-11745. Please see the migration documentation for further details.}

[asfimport]

Ben Kietzman / @bkietz:
Issue resolved by pull request 9715
#9715