mysqlctl does not find mysql_install_db in generic tarballs

[morgo]

Overview of the Issue

In a generic tarball, mysql_install_db will be located in the scripts/ directory:

morgo@ryzen:~/Downloads$ tar --gzip --list --verbose --file=mysql-5.6.44-linux-glibc2.12-x86_64.tar.gz  | grep mysql_install_db
-rw-r--r-- pb2user/common   14339 2019-03-15 01:55 mysql-5.6.44-linux-glibc2.12-x86_64/man/man1/mysql_install_db.1
-rwxr-xr-x pb2user/common   34558 2019-03-15 09:37 mysql-5.6.44-linux-glibc2.12-x86_64/scripts/mysql_install_db

In ./go/vt/mysqlctl/mysqld.go the binary is searched for with binaryPath:

  cmdPath, err := binaryPath(mysqlRoot, "mysql_install_db")
  if err != nil {
    return err
  }
  if _, _, err = execCmd(cmdPath, args, nil, mysqlRoot, nil); err != nil {
    log.Errorf("mysql_install_db failed: %v", err)
    return err
  }

This function lists a set of subdirs to search, of which scripts should be included:

// binaryPath does a limited path lookup for a command,
// searching only within sbin and bin in the given root.
func binaryPath(root, binary string) (string, error) {
  subdirs := []string{"sbin", "bin", "libexec"}
  for _, subdir := range subdirs {
    binPath := path.Join(root, subdir, binary)
    if _, err := os.Stat(binPath); err == nil {
      return binPath, nil
    }
  }
  return "", fmt.Errorf("%s not found in any of %s/{%s}",
    binary, root, strings.Join(subdirs, ","))
}

Reproduction Steps

Steps to reproduce this issue, example:

source ./dev.env

pgrep -f -l '(vtdataroot|VTDATAROOT)' # list Vitess processes
pkill -f '(vtdataroot|VTDATAROOT)' # kill Vitess processes

sleep 1

for process in `pgrep -f '(vtdataroot|VTDATAROOT)'`; do
 kill -9 $process
done;

export VT_MYSQL_ROOT=/usr/local/mysql
export VTDATAROOT=/tmp/vtdataroot
rm -rf /tmp/vtdataroot

cd examples/local/
./101_initial_cluster.sh

Errors with:

Starting MySQL for tablet zone1-0000000102...
E0702 11:48:24.391879   22619 mysqlctl.go:254] failed init mysql: mysql_install_db not found in any of /usr/local/mysql/{sbin,bin,libexec}
E0702 11:48:24.392027   22618 mysqlctl.go:254] failed init mysql: mysql_install_db not found in any of /usr/local/mysql/{sbin,bin,libexec}
E0702 11:48:24.392044   22620 mysqlctl.go:254] failed init mysql: mysql_install_db not found in any of /usr/local/mysql/{sbin,bin,libexec}

It's an easy fix:

morgo@ryzen:~/go/src/github.com/vitessio/src/vitess.io/vitess$ git diff ./go/vt/mysqlctl/mysqld.go
diff --git a/go/vt/mysqlctl/mysqld.go b/go/vt/mysqlctl/mysqld.go
index 029586d1c..c4f9e5380 100644
--- a/go/vt/mysqlctl/mysqld.go
+++ b/go/vt/mysqlctl/mysqld.go
@@ -453,7 +453,7 @@ func execCmd(name string, args, env []string, dir string, input io.Reader) (cmd
 // binaryPath does a limited path lookup for a command,
 // searching only within sbin and bin in the given root.
 func binaryPath(root, binary string) (string, error) {
-       subdirs := []string{"sbin", "bin", "libexec"}
+       subdirs := []string{"sbin", "bin", "libexec", "scripts"}
        for _, subdir := range subdirs {
                binPath := path.Join(root, subdir, binary)
                if _, err := os.Stat(binPath); err == nil {

Version

Built from master.

[morgo]

I discovered today this patch is also required for generic mariadb tarballs:

morgo@ryzen:~/Downloads$ tar --gzip --list --verbose --file=mariadb-10.0.38-linux-systemd-x86_64.tar.gz | grep mysql_install_db
-rw-r--r-- dbart/my       8488 2019-01-29 11:39 mariadb-10.0.38-linux-systemd-x86_64/man/man1/mysql_install_db.1
-rwxr-xr-x dbart/my      17025 2019-01-29 12:27 mariadb-10.0.38-linux-systemd-x86_64/scripts/mysql_install_db
morgo@ryzen:~/Downloads$ tar --gzip --list --verbose --file=mariadb-10.1.40-linux-systemd-x86_64.tar.gz | grep mysql_install_db
-rw-r--r-- dbart/my       8800 2019-05-07 14:49 mariadb-10.1.40-linux-systemd-x86_64/man/man1/mysql_install_db.1
-rwxr-xr-x dbart/my      19383 2019-05-07 15:38 mariadb-10.1.40-linux-systemd-x86_64/scripts/mysql_install_db
morgo@ryzen:~/Downloads$ tar --gzip --list --verbose --file=mariadb-10.2.25-linux-systemd-x86_64.tar.gz | grep mysql_install_db
-rw-r--r-- dbart/my       8800 2019-06-14 12:29 mariadb-10.2.25-linux-systemd-x86_64/man/man1/mysql_install_db.1
-rwxr-xr-x dbart/my      19257 2019-06-14 15:27 mariadb-10.2.25-linux-systemd-x86_64/scripts/mysql_install_db
morgo@ryzen:~/Downloads$ tar --gzip --list --verbose --file=mariadb-10.3.16-linux-x86_64.tar.gz | grep mysql_install_db
-rwxr-xr-x dbart/my      19458 2019-06-14 16:59 mariadb-10.3.16-linux-x86_64/scripts/mysql_install_db
-rw-r--r-- dbart/my       8800 2019-06-14 16:25 mariadb-10.3.16-linux-x86_64/man/man1/mysql_install_db.1