E2e Tests

Vitess End-to-End Tests

What end-to-end tests do

End-to-end tests spin up real Vitess binaries (vtgate, vttablet, vtctld, mysqlctl, etcd, vtorc) and real MySQL instances on the local machine. They exercise the full production stack: topology, replication, query routing, cluster operations.

All end-to-end tests live under go/test/endtoend/. The cluster harness lives in go/test/endtoend/cluster/.

Building binaries

Tests invoke binaries from $VTROOT/bin/. If source code for the binaries has changed, rebuild before running tests. Rebuilding is not needed if only test code under go/test/endtoend/ has changed, since test code is compiled by go test at run time.

source build.env
NOVTADMINBUILD=1 make build

Always rebuild after code changes so tests run against up-to-date binaries.

Running tests

source build.env
go test -count=1 -timeout 10m -run ^TestName$ vitess.io/vitess/go/test/endtoend/<pkg>

Use -timeout generously. End-to-end tests start entire clusters (etcd, MySQL, vttablet, vtgate) and can take minutes. Default 10m is safe for most tests. -count=1 disables caching, which is essential since these tests have side effects.

To run a specific subtest:

go test -count=1 -timeout 10m -run ^TestParent/SubTest$ vitess.io/vitess/go/test/endtoend/<pkg>

VTDATAROOT

VTDATAROOT is where all runtime data lives during test execution: MySQL data directories, logs, socket files, backups, and tmp directories. source build.env sets it to $VTROOT/vtdataroot by default.

Each test cluster creates a subdirectory vtroot_<port>/ under VTDATAROOT and sets VTDATAROOT to that subdirectory for the duration of the test.

Layout

$VTDATAROOT/
  vtroot_<port>/              # per-test-cluster root
    vt_0000000100/            # per-tablet directory (tablet UID 100)
      mysql.sock              # MySQL socket
      mysql.pid
      ...
    tmp_<port>/               # log directory for this cluster
      vtgate-stderr.txt
      vttablet-stderr.txt
      mysqlctl-stderr.txt
      *.INFO, *.WARNING, *.ERROR   # glog files
    backups/                  # backup data

Reading logs

When a test fails, read logs from the tmp directory inside the cluster's VTDATAROOT:

$VTDATAROOT/vtroot_<port>/tmp_<port>/

Look for *-stderr.txt files and glog files (*.INFO, *.WARNING, *.ERROR).

Clear between runs

Stale data in VTDATAROOT causes test failures: port conflicts, leftover MySQL data, stale socket files. Clear it between runs:

rm -rf $VTDATAROOT/vtroot_*

Do this before re-running tests that failed, especially if the previous run did not tear down cleanly (crash, timeout, ctrl-c).

Test structure

Each end-to-end test package starts a cluster.LocalProcessCluster (topo, vtctld, MySQL, vttablets, vtgate) before tests run, and tears it down after. Individual Test* functions run queries or operations against the live cluster.

Debugging failures

1. Clear VTDATAROOT: rm -rf $VTDATAROOT/vtroot_*
2. Rebuild binaries: make build
3. Run the failing test with -v
4. On failure, read logs from $VTDATAROOT/vtroot_*/tmp_*/
5. Check *-stderr.txt files first for startup errors
6. Check glog *.ERROR and *.WARNING files for runtime errors