Make vttestserver docker image work with vtctldclient

[GuptaManan100]

Description

While suggesting a way to create a new database in vttestserver with the managed mode, it was noticed that the docker image of vttestserver didn't actually support running any vtctldclient commands.

On further investigation it was found that this was happening because the bind address provided to vtcombo was hard-coded to 127.0.0.1 which meant that in a docker environment it would never accept any requests coming from the outside even if port-forwarding was used. Therefore, this PR made the changes to configure this value from vttestserver as a flag and augmented the docker image to use a new environment variable VTCOMBO_BIND_HOST to pass in the correct value.

After making these changes, we are able to run vtctld commands issued through the vtctldclient against a docker image running vttestserver. Moreover, we also able to access the vtcombo status page.

For example, if we run -

docker run --name=vttestserver \                      
-p 33577:33577 \
-p 33575:33575 \
-p 33574:33574 \
-e PORT=33574 \
-e KEYSPACES=test,unsharded \
-e NUM_SHARDS=2,1 \
-e MYSQL_MAX_CONNECTIONS=70000 \
-e MYSQL_BIND_HOST=0.0.0.0 \
-e VTCOMBO_BIND_HOST=0.0.0.0 \
--health-cmd="mysqladmin ping -h127.0.0.1 -P33577" \
--health-interval=5s \
--health-timeout=2s \
--health-retries=5 \
vitess/vttestserver:mysql80

We can connect to vtgate using the command mysql --host 127.0.0.1 --port 33577 --user "root". We can verify that we have two databases running -

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| test               |
| unsharded          |
| information_schema |
| mysql              |
| sys                |
| performance_schema |
+--------------------+
6 rows in set (0.01 sec)

We can also see the keyspaces by running the vtctldclient command like so -

vtctldclient --server 127.0.0.1:33575 GetKeyspaces              
[
  {
    "name": "test",
    "keyspace": {
      "sidecar_db_name": "_vt"
    }
  },
  {
    "name": "unsharded",
    "keyspace": {
      "sidecar_db_name": "_vt"
    }
  }
]

Then we can create a new database in the vtgate mysql shell -

mysql> create database fk_test;
Query OK, 1 row affected (5.25 sec)

We can verify that the new keyspace is created like so -

vtctldclient --server 127.0.0.1:33575 GetKeyspaces
[
  {
    "name": "fk_test",
    "keyspace": {
      "sidecar_db_name": "_vt"
    }
  },
  {
    "name": "test",
    "keyspace": {
      "sidecar_db_name": "_vt"
    }
  },
  {
    "name": "unsharded",
    "keyspace": {
      "sidecar_db_name": "_vt"
    }
  }
]

We can now create a local vschema file like so -

{
    "sidecar_db_name": "_vt",
    "foreignKeyMode": "managed",
    "tables": {
    }
}

We then use the vtctldclient to apply this vschema to the new keyspace -

vtctldclient --server 127.0.0.1:33575 ApplyVSchema --vschema-file vschema_fk_test.json fk_test 
New VSchema object:
{
  "sharded": false,
  "vindexes": {},
  "tables": {},
  "require_explicit_routing": false,
  "foreign_key_mode": "managed"
}
If this is not what you expected, check the input data (as JSON parsing will skip unexpected fields).

Finally, we can verify that the foreign key mode has been successfully changed by running the following query in vtgate mysql shell -

mysql> show vschema keyspaces;
+-----------+---------+-------------+---------+
| Keyspace  | Sharded | Foreign Key | Comment |
+-----------+---------+-------------+---------+
| test      | true    | unmanaged   |         |
| unsharded | false   | unmanaged   |         |
| fk_test   | false   | managed     |         |
+-----------+---------+-------------+---------+
3 rows in set (0.01 sec)

We can also access the /debug/status page from vtcombo by visiting the site http://localhost:33574/debug/status -

Tests to verify that vtctldclient works have also been added and ensured that they indeed work - PASS: TestVtctldCommands/vttestserver-e2etest/mysql80 (6.54s)

Related Issue(s)

• Fixes Feature Request: Allow new databases/keyspaces to run in foreignKeyMode=managed by default (in vttestserver) #14661

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on the CI
• Documentation was added or is not required - Update vttestserver docker image docs to show how it can work with vtctldclient website#1646

Deployment Notes

[vitess-bot]

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