send maintenance_window.hour even if it's zero, since that's a valid value

[modular-magician]

/cc @danawillow

[gburiola]

Hey @paddycarver / @danawillow , will this fix an issue like the one describe below?

1. settings.maintenance_window is NOT defined on terraform code

2. Apply creates the database_instance correctly

3. Second run of apply shows the following diff:

   ~ google_sql_database_instance.NAME
       settings.0.maintenance_window.#: "0" => "1"
   

Trying to apply the diff above fails with:

* google_sql_database_instance.NAME: Error, failed to update instance NAME: googleapi: 
  Error 400: This operation isn"t valid for this instance., invalidOperation

That is probably because the PUT request contains an empty maintenanceWindow:

plugin.terraform-provider-google_v1.20.0_x4: ---[ REQUEST ]---------------------------------------
plugin.terraform-provider-google_v1.20.0_x4: PUT /sql/v1beta4/projects/PROJECT/instances/NAME?alt=json&prettyPrint=false HTTP/1.1
plugin.terraform-provider-google_v1.20.0_x4: Host: www.googleapis.com
plugin.terraform-provider-google_v1.20.0_x4: User-Agent: google-api-go-client/0.5 Terraform/0.11.7 (+https://www.terraform.io) terraform-provider-google/1.20.0
plugin.terraform-provider-google_v1.20.0_x4: Content-Length: 2773
plugin.terraform-provider-google_v1.20.0_x4: Content-Type: application/json
plugin.terraform-provider-google_v1.20.0_x4: Accept-Encoding: gzip
plugin.terraform-provider-google_v1.20.0_x4:
plugin.terraform-provider-google_v1.20.0_x4: {
plugin.terraform-provider-google_v1.20.0_x4:  "backendType": "SECOND_GEN",
plugin.terraform-provider-google_v1.20.0_x4:  "connectionName": "PROJECT:europe-west2:NAME",
plugin.terraform-provider-google_v1.20.0_x4:  "databaseVersion": "MYSQL_5_7",
plugin.terraform-provider-google_v1.20.0_x4:  "instanceType": "CLOUD_SQL_INSTANCE",
plugin.terraform-provider-google_v1.20.0_x4:  "settings": {
<REMOVED A FEW LINES>
plugin.terraform-provider-google_v1.20.0_x4:   "locationPreference": {},
plugin.terraform-provider-google_v1.20.0_x4:   "maintenanceWindow": {},
plugin.terraform-provider-google_v1.20.0_x4:   "pricingPlan": "PER_USE",
plugin.terraform-provider-google_v1.20.0_x4:   "replicationType": "SYNCHRONOUS",
plugin.terraform-provider-google_v1.20.0_x4:   "settingsVersion": "1",
plugin.terraform-provider-google_v1.20.0_x4:   "tier": "db-n1-standard-1"


plugin.terraform-provider-google_v1.20.0_x4: ---[ RESPONSE ]--------------------------------------
plugin.terraform-provider-google_v1.20.0_x4: HTTP/2.0 400 Bad Request
plugin.terraform-provider-google_v1.20.0_x4: Alt-Svc: quic=":443"; ma=2592000; v="44,43,39,35"
plugin.terraform-provider-google_v1.20.0_x4: Cache-Control: private, max-age=0
plugin.terraform-provider-google_v1.20.0_x4: Content-Type: application/json; charset=UTF-8
plugin.terraform-provider-google_v1.20.0_x4: Date: Tue, 18 Dec 2018 17:44:23 GMT
plugin.terraform-provider-google_v1.20.0_x4: Expires: Tue, 18 Dec 2018 17:44:23 GMT
plugin.terraform-provider-google_v1.20.0_x4: Server: GSE
plugin.terraform-provider-google_v1.20.0_x4: Vary: Origin
plugin.terraform-provider-google_v1.20.0_x4: Vary: X-Origin
plugin.terraform-provider-google_v1.20.0_x4: X-Content-Type-Options: nosniff
plugin.terraform-provider-google_v1.20.0_x4: X-Frame-Options: SAMEORIGIN
plugin.terraform-provider-google_v1.20.0_x4: X-Xss-Protection: 1; mode=block
plugin.terraform-provider-google_v1.20.0_x4:
plugin.terraform-provider-google_v1.20.0_x4: {
plugin.terraform-provider-google_v1.20.0_x4:  "error": {
plugin.terraform-provider-google_v1.20.0_x4:   "errors": [
plugin.terraform-provider-google_v1.20.0_x4:    {
plugin.terraform-provider-google_v1.20.0_x4:     "domain": "global",
plugin.terraform-provider-google_v1.20.0_x4:     "reason": "invalidOperation",
plugin.terraform-provider-google_v1.20.0_x4:     "message": "This operation isn\"t valid for this instance."
plugin.terraform-provider-google_v1.20.0_x4:    }
plugin.terraform-provider-google_v1.20.0_x4:   ],
plugin.terraform-provider-google_v1.20.0_x4:   "code": 400,
plugin.terraform-provider-google_v1.20.0_x4:   "message": "This operation isn\"t valid for this instance."
plugin.terraform-provider-google_v1.20.0_x4:  }
plugin.terraform-provider-google_v1.20.0_x4: }

[danawillow]

Hmm, just glancing at it that looks different to me. Can you file a new issue for that?

[gburiola]

Thanks Dana.

I've opened #2716

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. If you feel I made an error 🤖 🙉 , please reach out to my human friends 👉 hashibot-feedback@hashicorp.com. Thanks!