feat: update sql server flex configuration for user and database (#46)

## Description

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At least please give us some description what you are trying to achieve and why your change is needed. -->

relates to #1234

## Checklist

- [ ] Issue was linked above
- [ ] Code format was applied: `make fmt`
- [ ] Examples were added / adjusted (see `examples/` directory)
- [x] Docs are up-to-date: `make generate-docs` (will be checked by CI)
- [ ] Unit tests got implemented or updated
- [ ] Acceptance tests got implemented or updated (see e.g. [here](f5f99d1709/stackit/internal/services/dns/dns_acc_test.go))
- [x] Unit tests are passing: `make test` (will be checked by CI)
- [x] No linter issues: `make lint` (will be checked by CI)

Reviewed-on: #46
Reviewed-by: Marcel_Henselin <marcel.henselin@stackit.cloud>
Co-authored-by: Andre Harms <andre.harms@stackit.cloud>
Co-committed-by: Andre Harms <andre.harms@stackit.cloud>

stackit/internal/services/sqlserverflexalpha/database/datasource.go

@@ -2,9 +2,12 @@ package sqlserverflexalpha
 
 import (
 	"context"
+	"fmt"
+	"net/http"
 
 	"github.com/hashicorp/terraform-plugin-framework/datasource"
 	"github.com/hashicorp/terraform-plugin-framework/datasource/schema"
+	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-framework/types"
 	"github.com/hashicorp/terraform-plugin-log/tflog"
 	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/pkg_gen/sqlserverflexalpha"
@@ -12,6 +15,7 @@ import (
 	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/core"
 	sqlserverflexalphaGen "tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/services/sqlserverflexalpha/database/datasources_gen"
 	sqlserverflexUtils "tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/services/sqlserverflexalpha/utils"
+	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/utils"
 )
 
 // dataSourceModel maps the data source schema data.
@@ -22,6 +26,7 @@ type dataSourceModel struct {
 
 var _ datasource.DataSource = (*databaseDataSource)(nil)
 
+// NewDatabaseDataSource creates a new database data source.
 func NewDatabaseDataSource() datasource.DataSource {
 	return &databaseDataSource{}
 }
@@ -31,6 +36,7 @@ type databaseDataSource struct {
 	providerData core.ProviderData
 }
 
+// Metadata returns the data source type name.
 func (d *databaseDataSource) Metadata(
 	_ context.Context,
 	req datasource.MetadataRequest,
@@ -39,6 +45,7 @@ func (d *databaseDataSource) Metadata(
 	resp.TypeName = req.ProviderTypeName + "_sqlserverflexalpha_database"
 }
 
+// Schema defines the data source schema.
 func (d *databaseDataSource) Schema(ctx context.Context, _ datasource.SchemaRequest, resp *datasource.SchemaResponse) {
 	s := sqlserverflexalphaGen.DatabaseDataSourceSchema(ctx)
 	s.Attributes["id"] = schema.StringAttribute{
@@ -67,24 +74,92 @@ func (d *databaseDataSource) Configure(
 		return
 	}
 	d.client = apiClient
-	tflog.Info(ctx, "SQL SERVER Flex database client configured")
+	tflog.Info(ctx, "SQL SERVER Flex alpha database client configured")
 }
 
+// Read retrieves the resource's state from the API.
 func (d *databaseDataSource) Read(ctx context.Context, req datasource.ReadRequest, resp *datasource.ReadResponse) {
-	var data dataSourceModel
-
-	// Read Terraform configuration data into the model
-	resp.Diagnostics.Append(req.Config.Get(ctx, &data)...)
 
+	var model dataSourceModel
+	diags := req.Config.Get(ctx, &model)
+	resp.Diagnostics.Append(diags...)
 	if resp.Diagnostics.HasError() {
 		return
 	}
 
-	// Todo: Read API call logic
+	ctx = core.InitProviderContext(ctx)
 
-	// Example data value setting
-	// data.Id = types.StringValue("example-id")
+	// Extract identifiers from the plan
+	projectId := model.ProjectId.ValueString()
+	instanceId := model.InstanceId.ValueString()
+	region := d.providerData.GetRegionWithOverride(model.Region)
+	databaseName := model.DatabaseName.ValueString()
 
-	// Save data into Terraform state
-	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
+	ctx = tflog.SetField(ctx, "project_id", projectId)
+	ctx = tflog.SetField(ctx, "instance_id", instanceId)
+	ctx = tflog.SetField(ctx, "region", region)
+	ctx = tflog.SetField(ctx, "database_name", databaseName)
+
+	// Fetch database from the API
+	databaseResp, err := d.client.GetDatabaseRequest(ctx, projectId, region, instanceId, databaseName).Execute()
+
+	if resp.Diagnostics.HasError() {
+		return
+	}
+	if err != nil {
+		handleReadError(ctx, &resp.Diagnostics, err, projectId, instanceId)
+		resp.State.RemoveResource(ctx)
+		return
+	}
+
+	ctx = core.LogResponse(ctx)
+
+	// Map response body to schema and populate Computed attribute values
+	err = mapFields(databaseResp, &model, region)
+	if err != nil {
+		core.LogAndAddError(
+			ctx,
+			&resp.Diagnostics,
+			"Error reading database",
+			fmt.Sprintf("Processing API payload: %v", err),
+		)
+		return
+	}
+
+	// Set refreshed state
+	diags = resp.State.Set(ctx, model)
+	resp.Diagnostics.Append(diags...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	tflog.Info(ctx, "SQL Server Flex alpha database read")
+}
+
+// handleReadError centralizes API error handling for the Read operation.
+func handleReadError(ctx context.Context, diags *diag.Diagnostics, err error, projectId, instanceId string) {
+	utils.LogError(
+		ctx,
+		diags,
+		err,
+		"Reading database",
+		fmt.Sprintf(
+			"Could not retrieve database for instance %q in project %q.",
+			instanceId,
+			projectId,
+		),
+		map[int]string{
+			http.StatusBadRequest: fmt.Sprintf(
+				"Invalid request parameters for project %q and instance %q.",
+				projectId,
+				instanceId,
+			),
+			http.StatusNotFound: fmt.Sprintf(
+				"Database, instance %q, or project %q not found.",
+				instanceId,
+				projectId,
+			),
+			http.StatusForbidden: fmt.Sprintf("Forbidden access to project %q.", projectId),
+		},
+	)
 }