DRILL-5126: Provide simplified, unified "cluster fixture" for test
Drill provides a robust selection of test frameworks that have evolved to satisfy the needs of a variety of test cases.
However, some do some of what a given test needs, while others to other parts. Also, the various frameworks make
assumptions (in the form of boot-time configuration) that differs from what some test may need, forcing the test
to start, then stop, then restart a Drillbit - an expensive operation.
Also, many ways exist to run queries, but they all do part of the job. Several ways exist to channge
runtime options.
This checkin shamelessly grabs the best parts from existing frameworks, adds a fluent builder facade
and provides a complete, versitie test framework for new tests. Old tests are unaffected by this
new code.
An adjustment was made to allow use of the existing TestBuilder mechanism. TestBuilder used to
depend on static members of BaseTestQuery. A "shim" allows the same code to work in the old
way for old tests, but with the new ClusterFixture for new tests.
Details are in the org.apache.drill.test.package-info.java file.
This commit modifies a single test case, TestSimpleExternalSort, to use the new framework.
More cases will follow once this framework itself is committed.
Also, the framework will eventually allow use of the extended mock data source
from SQL. However, that change must await checkin of the mock data source changes.
Includes a LogFixture that allows setting logger options per test to simplify debugging via tests.
Also includes a “summary listener” to run a query and return a summary of the
run. Handy to simply verify that a query runs and to time it.
Added an async query runner for tests that want to run multiple
concurrent queries.
closes #710
