Extends CloudSql with replicaConfiguration

[mcbenjemaa]

Signed-off-by: Mohamed Chiheb mc.benjemaa@gmail.com

Description of your changes

In order to be able to provision CloudSql failOver replicas, provider GCP CloudSql instance must include replicaConfiguration

In this PR:

• I've added support for replicaConfiguration

• Added support for replicaConfiguration.mysqlReplicaConfiguration with ability to hide sensitive data (Explained below)

Failover replica

To create a failover replica you must have a master replica either created manually or provisioned using crossplane.

Specify those values:

  forProvider:
    masterInstanceName: <projectId>:<masterIntanceName>
    replicaConfiguration:
      failoverTarget: true

If you, provisioned the master instance using crossplane, you need to update the master:

  forProvider:
     failoverReplica:
        name: "<replicaName>"

Sensitive Data

I have the feeling that the fields under replicaConfiguration.mysqlReplicaConfiguration are sensitive:

Thus, I made this concept of fetching those fields from a provided secret:

example:

  forProvider:
    replicaConfiguration:
      failoverTarget: false
      mysqlReplicaConfiguration:
        secretRef:         # secretRef that contain data
          name: cloudsql-replica-creds
          namespace: default
        usernameKey: "username"  # a reference key from the specified secret above
        passwordKey: "password"    # a reference key from the specified secret above

what do you think about this config?

WIP

Still WIP

TBD

Fixes # ?

related #388

I have:

• Read and followed Crossplane's contribution process.
• Run make reviewable test to ensure this PR is ready for review.

How has this code been tested

Tested on a GCP account.

[turkenh]

Instead of putting all configurations in a secret and receiving which parameter represented by which key, I would suggest to have separate fields for sensitive ones. For example:

PasswordSecretRef *v1.SecretKeySelector `json:"passwordSecretRef,omitempty" tf:"-"`

This would still allow us to keep all information in a single secret but would be more explicit and flexible, for example, client cert key can be in secret A but ca cert can be in secret B.

And we can keep non sensitive ones, e.g. username, simply in spec. For public keys, I am a bit unsure though, since even it is not sensitive, I believe would be hard to maintain in the spec.

[mcbenjemaa]

Definitely that's great.
But, I'm wondering about controller implementation.

This will end up checking each secretRef provided and fetch it accordingly,
thinking about, in each reconciliation loop, the controller will fetch those secrets as user provided.
Isn't a bit noisy... (for controller perspective, as this will be implemented in the Observe())

[turkenh]

Yeah, that's a good point.

However, controller runtime's caching would help with this and we won't (really) fetch those secrets (or that secret, if all put into 1 with different keys) in each reconcile from API Server.

[turkenh]

Suggested change

	SslCipher *string `json:"sslCipher,omitempty"`
	SSLCipher *string `json:"sslCipher,omitempty"`

[turkenh]

Suggested change

	CaCertificateKey *string `json:"caCertificateKey,omitempty"`
	CACertificateKey *string `json:"caCertificateKey,omitempty"`

[turkenh]

Is there a possibility that other database types could be supported in the future? Asking because on terraform side no dedicated parameter for Mysql, rather there is only a note that replica_configuration is only valid for mysql:
https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/sql_database_instance#ca_certificate

[turkenh]

Suggested change

	MysqlReplicaConfiguration *MySqlReplicaConfiguration `json:"mysqlReplicaConfiguration,omitempty"`
	MySQLReplicaConfiguration *MySQLReplicaConfiguration `json:"mySQLReplicaConfiguration,omitempty"`

[turkenh]

As mentioned in the previous comment, by convention, the following API is preferable since it is more explicit and flexible:

Suggested change

	mysqlReplicaConfiguration:
	secretRef:
	name: cloudsql-replica-creds
	namespace: default
	usernameKey: "username"
	passwordKey: "password"
	mysqlReplicaConfiguration:
	username: admin
	passwordSecretRef:
	name: cloudsql-replica-creds
	namespace: default
	key: password
	caCertificateSecretRef:
	name: cloudsql-replica-certs
	namespace: default
	key: ca.crt
	clientCertificateSecretRef:
	name: cloudsql-replica-certs
	namespace: default
	key: tls.crt
	clientKeyCertificateSecretRef:
	name: cloudsql-replica-certs
	namespace: default
	key: tls.key

[mcbenjemaa]

sorry for the delay! I will try to adapt the changes soon.