CloudMigrations: Query Grafana Migration Status for status while the snapshot is in the cloud (#90314)

* implement querying gms for snapshot status

* add some documentation

* provide snapshot resources after snapshot is created

* add rate limiting to backend

* fix compilation error

* fix typo

* add unit tests

* finish merge

* lint

* swagger gen

* more testing

* remove duplicate test

* address a couple PR comments

* update switch statement to a map

* add timeouts to gms client through the http client

* remove extra whitespace

* put method back where it was so the PR is less confusing

* fix tests

* add todo

* fix final unit test

pkg/services/cloudmigration/model.go

@@ -55,25 +55,24 @@ type CloudMigrationSnapshot struct {
 type SnapshotStatus string
 
 const (
-	SnapshotStatusInitializing      = "initializing"
-	SnapshotStatusCreating          = "creating"
-	SnapshotStatusPendingUpload     = "pending_upload"
-	SnapshotStatusUploading         = "uploading"
-	SnapshotStatusPendingProcessing = "pending_processing"
-	SnapshotStatusProcessing        = "processing"
-	SnapshotStatusFinished          = "finished"
-	SnapshotStatusError             = "error"
-	SnapshotStatusUnknown           = "unknown"
+	SnapshotStatusCreating          SnapshotStatus = "creating"
+	SnapshotStatusPendingUpload     SnapshotStatus = "pending_upload"
+	SnapshotStatusUploading         SnapshotStatus = "uploading"
+	SnapshotStatusPendingProcessing SnapshotStatus = "pending_processing"
+	SnapshotStatusProcessing        SnapshotStatus = "processing"
+	SnapshotStatusFinished          SnapshotStatus = "finished"
+	SnapshotStatusCanceled          SnapshotStatus = "canceled"
+	SnapshotStatusError             SnapshotStatus = "error"
 )
 
 type CloudMigrationResource struct {
 	ID  int64  `xorm:"pk autoincr 'id'"`
 	UID string `xorm:"uid"`
 
-	Type   MigrateDataType `xorm:"resource_type"`
-	RefID  string          `xorm:"resource_uid"`
-	Status ItemStatus      `xorm:"status"`
-	Error  string          `xorm:"error_string"`
+	Type   MigrateDataType `xorm:"resource_type" json:"type"`
+	RefID  string          `xorm:"resource_uid" json:"refId"`
+	Status ItemStatus      `xorm:"status" json:"status"`
+	Error  string          `xorm:"error_string" json:"error"`
 
 	SnapshotUID string `xorm:"snapshot_uid"`
 }
@@ -212,3 +211,20 @@ type StartSnapshotResponse struct {
 	UploadURL            string `json:"uploadURL"`
 	EncryptionKey        string `json:"encryptionKey"`
 }
+
+// Based on Grafana Migration Service DTOs
+type GetSnapshotStatusResponse struct {
+	State   SnapshotState            `json:"state"`
+	Results []CloudMigrationResource `json:"results"`
+}
+
+type SnapshotState string
+
+const (
+	SnapshotStateInitialized SnapshotState = "INITIALIZED"
+	SnapshotStateProcessing  SnapshotState = "PROCESSING"
+	SnapshotStateFinished    SnapshotState = "FINISHED"
+	SnapshotStateCanceled    SnapshotState = "CANCELED"
+	SnapshotStateError       SnapshotState = "ERROR"
+	SnapshotStateUnknown     SnapshotState = "UNKNOWN"
+)