Google Spanner: How to list databases?-CodePudding

Using C#, I am trying to list the available databases on a Google Spanner Instance. There seems little to no decent documentation that actually explains how to use the Google.Spanner Nuget libs.

From what I can tell there are a few libraries to use. The first is the main SpannerClient which gives you a client to execute sql queries on a given database. I have this working fine. However in order to present the list of available databases to my users, I'd like to get the list of available databases. I have found the package Google.Cloud.Spanner.Admin.Instance.V1; but almost no docs to explain how to use. So I've been coding in the dark, so far I've written the following test code:

var credentials = GoogleCredential.FromJson(_apiKey);
var client = new InstanceAdminClientBuilder();
client.Credential = credentials;

var clientInst = client.Build();
ListInstancesRequest listInstanceRequest = new ListInstancesRequest();
listInstanceRequest.Parent = _projectId;
var res = clientInst.ListInstances(listInstanceRequest);

I get an :

"InvalidArgument - Invalid ListInstances request."

which suggests I've not done it right but I can't find any decent docs.

So any help welcome!!

CodePudding user response：

Listing instances isn't the same as listing databases. If you want to list databases, you should use the Google.Cloud.Spanner.Admin.Database.V1 package, with DatabaseAdminClient.

Next, the Parent property in any list operation should be the full resource name, e.g. projects/my_project_id rather than just the project ID. Normally the best way of approaching this is to use the generated resource name types.

So for example:

var client = DatabaseAdminClient.Create();
var instanceName = new InstanceName(projectId, instanceId);
var databases = client.ListDatabases(instanceName);
foreach (var database in databases)
{
    Console.WriteLine(database.Name);
}

If you want to list the instances for the project, you'd use:

var client = InstanceAdminClient.Create();
var projectName = new ProjectName(projectId);
var instances = client.ListInstances(projectName);
foreach (var instance in instances)
{
    Console.WriteLine(instance.Name);
}