feat(application) update CRUD function for application resource

This commit includes several updates to the resource CRUD functions in the Juju provider. The changes include:

- Added error handling for application not found in `handleApplicationNotFoundError` function.
- Added storage conintes to Create and Read functions
- Modifier retry process to read application changes, to be able to wait
  for storage creation

docs/resources/application.md

@@ -78,6 +78,7 @@ resource "juju_application" "placement_example" {
 		  latest revision.
 	    * If the charm revision or channel are not updated, then no changes will take 
 		  place (juju does not have an "un-attach" command for resources).
+- `storage` (Attributes Set) Configure storage constraints for the juju application. (see [below for nested schema](#nestedatt--storage))
 - `trust` (Boolean) Set the trust for the application.
 - `units` (Number) The number of application units to deploy for the charm.
 
@@ -122,6 +123,20 @@ Optional:
 - `endpoints` (String) Expose only the ports that charms have opened for this comma-delimited list of endpoints
 - `spaces` (String) A comma-delimited list of spaces that should be able to access the application ports once exposed.
 
+
+<a id="nestedatt--storage"></a>
+### Nested Schema for `storage`
+
+Required:
+
+- `label` (String) The specific storage option defined in the charm.
+- `size` (String) The size of each volume. E.g. 100G
+
+Optional:
+
+- `count` (Number) The number of volumes.
+- `pool` (String) Name the storage pool to use. E.g. ebs on aws.
+
 ## Import
 
 Import is supported using the following syntax:

docs/resources/machine.md

@@ -32,7 +32,7 @@ resource "juju_machine" "this_machine" {
 
 - `base` (String) The operating system to install on the new machine(s). E.g. [email protected].
 - `constraints` (String) Machine constraints that overwrite those available from 'juju get-model-constraints' and provider's defaults.
-- `disks` (String) Storage constraints for disks to attach to the machine(s).
+- `disks` (String) StorageContraints constraints for disks to attach to the machine(s).
 - `name` (String) A name for the machine resource in Terraform.
 - `placement` (String) Additional information about how to allocate the machine in the cloud.
 - `private_key_file` (String) The file path to read the private key from.

go.mod

@@ -11,6 +11,7 @@ require (
 )
 
 require (
+	github.com/dustin/go-humanize v1.0.1
 	github.com/hashicorp/terraform-plugin-framework v1.7.0
 	github.com/hashicorp/terraform-plugin-framework-validators v0.12.0
 	github.com/hashicorp/terraform-plugin-go v0.23.0
@@ -26,6 +27,7 @@ require (
 	github.com/juju/names/v5 v5.0.0
 	github.com/juju/retry v1.0.0
 	github.com/juju/utils/v3 v3.1.1
+	github.com/juju/utils/v4 v4.0.2
 	github.com/juju/version/v2 v2.0.1
 	github.com/rs/zerolog v1.32.0
 	github.com/stretchr/testify v1.9.0
@@ -70,7 +72,6 @@ require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/distribution/reference v0.5.0 // indirect
 	github.com/docker/distribution v2.8.3+incompatible // indirect
-	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/emicklei/go-restful/v3 v3.11.0 // indirect
 	github.com/fatih/color v1.16.0 // indirect
 	github.com/go-logr/logr v1.4.1 // indirect
@@ -125,6 +126,7 @@ require (
 	github.com/juju/idmclient/v2 v2.0.0 // indirect
 	github.com/juju/jsonschema v1.0.0 // indirect
 	github.com/juju/loggo v1.0.0 // indirect
+	github.com/juju/loggo/v2 v2.0.0 // indirect
 	github.com/juju/lru v1.0.0 // indirect
 	github.com/juju/lumberjack/v2 v2.0.2 // indirect
 	github.com/juju/mgo/v3 v3.0.4 // indirect

go.sum

@@ -360,6 +360,8 @@ github.com/juju/juju v0.0.0-20240415234708-a7538882134d h1:yK8L5+7fJvzsNkjUkkEps
 github.com/juju/juju v0.0.0-20240415234708-a7538882134d/go.mod h1:8W1iXQ/tGftslRzNF/1U8mVZFjtqc0zZKygwuIcmbPI=
 github.com/juju/loggo v1.0.0 h1:Y6ZMQOGR9Aj3BGkiWx7HBbIx6zNwNkxhVNOHU2i1bl0=
 github.com/juju/loggo v1.0.0/go.mod h1:NIXFioti1SmKAlKNuUwbMenNdef59IF52+ZzuOmHYkg=
+github.com/juju/loggo/v2 v2.0.0 h1:PzyVIn+NgoZ22QUtPgKF/lh+6SnaCOEXhcP+sE4FhOk=
+github.com/juju/loggo/v2 v2.0.0/go.mod h1:647d6WvXBLj5lvka2qBvccr7vMIvF2KFkEH+0ZuFOUM=
 github.com/juju/lru v1.0.0 h1:FP8mBNF3jBnKwGO5PtsR+8iIegx8DREfhRhpcGpYcn4=
 github.com/juju/lru v1.0.0/go.mod h1:YauKGp6PAhOQyGuTOkiFdXVP1jR3vLkp/FI71GcpYcQ=
 github.com/juju/lumberjack/v2 v2.0.2 h1:FlxrR62Vb7FfN7jwpSBqqereyq5bBQUF0LqOhZ2VGeI=
@@ -402,14 +404,16 @@ github.com/juju/rpcreflect v1.2.0/go.mod h1:yWSyMkWOwQGqUVxvboHn1c3CuCQrQ5LgV//8
 github.com/juju/schema v1.0.0/go.mod h1:Y+ThzXpUJ0E7NYYocAbuvJ7vTivXfrof/IfRPq/0abI=
 github.com/juju/schema v1.2.0 h1:+XywM0pYzuhGebQiK1aR4Bj7Q7nLV5MihcOgq6dLLxs=
 github.com/juju/schema v1.2.0/go.mod h1:VdljuJLc45loM79LYm4yKKmPJwK1bPKRekvMVlfywU0=
-github.com/juju/testing v1.1.0 h1:+WWez0vCu6dtnpLIzfuuo3bN3x62LBIyMDCfvMYP+Qg=
-github.com/juju/testing v1.1.0/go.mod h1:1XQGptw6JWFvRWb3ewilUdTBG0oGcoI2kdX9Z1VEzhU=
+github.com/juju/testing v1.2.0 h1:Q0wxjaxx4XPVEN+SgzxKr3d82pjmSBcuM3WndAU391c=
+github.com/juju/testing v1.2.0/go.mod h1:lqZVzNwBKAbylGZidK77ts6kIdoOkmD52+4m0ysetPo=
 github.com/juju/txn/v3 v3.0.2 h1:ibKhRlQmslPj88QfxND8hX4Sv6rTRKOb+HSp/ti1sEg=
 github.com/juju/txn/v3 v3.0.2/go.mod h1:DlFlqNZkgzE4NolIxhSvYOok/heIOjhXLx3Z5oUTyy4=
 github.com/juju/usso v1.0.1 h1:zyQhSUJnhFZdPqVAmPeqXYlnYXv+i0Cp1Ii+aziMXGs=
 github.com/juju/usso v1.0.1/go.mod h1:3cvBcGVmWXyHhrBHBQtpNBzca/JRg4S5XH88Hj/NsYA=
 github.com/juju/utils/v3 v3.1.1 h1:shEMr/4Wkw0YCOPz5IFOYkLv1ec50pzRi59TRl0qQ/0=
 github.com/juju/utils/v3 v3.1.1/go.mod h1:nAj3sHtdYfAkvnkqttTy3Xzm2HzkD9Hfgnc+upOW2Z8=
+github.com/juju/utils/v4 v4.0.2 h1:lh1cPruYCPLWBLuZpaAP18cc+3j9X/JsLExjwQ/+NxQ=
+github.com/juju/utils/v4 v4.0.2/go.mod h1:j5wVHbRzw2LF85mb3H46cPPXBkyw5k4laDL6cOW55LY=
 github.com/juju/version/v2 v2.0.1 h1:4psP9XDv8qIbSdv3llCmcmBXe+wvm57BvYp2sG/i6zc=
 github.com/juju/version/v2 v2.0.1/go.mod h1:OK+DKO9ve3fFCVUZGT8ZbUWU2TnZh914S6gMhiM2hXg=
 github.com/juju/webbrowser v1.0.0 h1:JLdmbFtCGY6Qf2jmS6bVaenJFGIFkdF1/BjUm76af78=

internal/juju/applications.go

@@ -41,6 +41,7 @@ import (
 	"github.com/juju/juju/core/network"
 	"github.com/juju/juju/environs/config"
 	"github.com/juju/juju/rpc/params"
+	jujustorage "github.com/juju/juju/storage"
 	jujuversion "github.com/juju/juju/version"
 	"github.com/juju/names/v5"
 	"github.com/juju/retry"
@@ -59,6 +60,17 @@ func (ae *applicationNotFoundError) Error() string {
 	return fmt.Sprintf("application %s not found", ae.appName)
 }
 
+var StorageNotFoundError = &storageNotFoundError{}
+
+// StorageNotFoundError
+type storageNotFoundError struct {
+	storageName string
+}
+
+func (se *storageNotFoundError) Error() string {
+	return fmt.Sprintf("storage %s not found", se.storageName)
+}
+
 type applicationsClient struct {
 	SharedClient
 	controllerVersion version.Number
@@ -125,21 +137,22 @@ func ConfigEntryToString(input interface{}) string {
 }
 
 type CreateApplicationInput struct {
-	ApplicationName  string
-	ModelName        string
-	CharmName        string
-	CharmChannel     string
-	CharmBase        string
-	CharmSeries      string
-	CharmRevision    int
-	Units            int
-	Trust            bool
-	Expose           map[string]interface{}
-	Config           map[string]string
-	Placement        string
-	Constraints      constraints.Value
-	EndpointBindings map[string]string
-	Resources        map[string]int
+	ApplicationName   string
+	ModelName         string
+	CharmName         string
+	CharmChannel      string
+	CharmBase         string
+	CharmSeries       string
+	CharmRevision     int
+	Units             int
+	Trust             bool
+	Expose            map[string]interface{}
+	Config            map[string]string
+	Placement         string
+	Constraints       constraints.Value
+	EndpointBindings  map[string]string
+	Resources         map[string]int
+	StorageContraints map[string]jujustorage.Constraints
 }
 
 // validateAndTransform returns transformedCreateApplicationInput which
@@ -156,6 +169,7 @@ func (input CreateApplicationInput) validateAndTransform(conn api.Connection) (p
 	parsed.trust = input.Trust
 	parsed.units = input.Units
 	parsed.resources = input.Resources
+	parsed.storage = input.StorageContraints
 
 	appName := input.ApplicationName
 	if appName == "" {
@@ -241,6 +255,7 @@ type transformedCreateApplicationInput struct {
 	trust            bool
 	endpointBindings map[string]string
 	resources        map[string]int
+	storage          map[string]jujustorage.Constraints
 }
 
 type CreateApplicationResponse struct {
@@ -266,6 +281,7 @@ type ReadApplicationResponse struct {
 	Principal        bool
 	Placement        string
 	EndpointBindings map[string]string
+	Storage          map[string]jujustorage.Constraints
 	Resources        map[string]int
 }
 
@@ -364,6 +380,7 @@ func (c applicationsClient) deployFromRepository(applicationAPIClient *apiapplic
 		Revision:         &transformedInput.charmRevision,
 		Trust:            transformedInput.trust,
 		Resources:        resources,
+		Storage:          transformedInput.storage,
 	})
 	return errors.Join(errs...)
 }
@@ -734,7 +751,7 @@ func (c applicationsClient) ReadApplicationWithRetryOnNotFound(ctx context.Conte
 		Func: func() error {
 			var err error
 			output, err = c.ReadApplication(input)
-			if errors.As(err, &ApplicationNotFoundError) {
+			if errors.As(err, &ApplicationNotFoundError) || errors.As(err, &StorageNotFoundError) {
 				return err
 			} else if err != nil {
 				// Log the error to the terraform Diagnostics to be
@@ -759,6 +776,18 @@ func (c applicationsClient) ReadApplicationWithRetryOnNotFound(ctx context.Conte
 			if len(machines) != output.Units {
 				return fmt.Errorf("ReadApplicationWithRetryOnNotFound: need %d machines, have %d", output.Units, len(machines))
 			}
+
+			// NOTE: Application can always have storages. However, they
+			// will not be listed right after the application is created. So
+			// we need to wait for the storages to be ready. And we need to
+			// check if all storage contraints have pool equal "" and size equal 0
+			// to drop the error.
+			for _, storage := range output.Storage {
+				if storage.Pool == "" || storage.Size == 0 {
+					return fmt.Errorf("ReadApplicationWithRetryOnNotFound: no storages found in output")
+				}
+			}
+
 			// NOTE: An IAAS subordinate should also have machines. However, they
 			// will not be listed until after the relation has been created.
 			// Those happen with the integration resource which will not be
@@ -785,6 +814,47 @@ func (c applicationsClient) ReadApplicationWithRetryOnNotFound(ctx context.Conte
 	return output, retryErr
 }
 
+func transformToStorageConstraints(
+	storageDetailsSlice []params.StorageDetails,
+	filesystemDetailsSlice []params.FilesystemDetails,
+	volumeDetailsSlice []params.VolumeDetails,
+) map[string]jujustorage.Constraints {
+	storage := make(map[string]jujustorage.Constraints)
+	for _, storageDetails := range storageDetailsSlice {
+		// switch base on storage kind
+		switch storageDetails.Kind.String() {
+		case "filesystem":
+			for _, fd := range filesystemDetailsSlice {
+				if fd.Storage.StorageTag == storageDetails.StorageTag {
+					// Cut 'storage-' prefix from the storage tag and `-NUMBER` suffix
+					storageLabel := getStorageLabel(storageDetails)
+					storage[storageLabel] = jujustorage.Constraints{
+						Pool:  fd.Info.Pool,
+						Size:  fd.Info.Size,
+						Count: 1,
+					}
+				}
+			}
+		case "block":
+			for _, vd := range volumeDetailsSlice {
+				if vd.Storage.StorageTag == storageDetails.StorageTag {
+					storageLabel := getStorageLabel(storageDetails)
+					storage[storageLabel] = jujustorage.Constraints{
+						Pool:  vd.Info.Pool,
+						Size:  vd.Info.Size,
+						Count: 1,
+					}
+				}
+			}
+		}
+	}
+	return storage
+}
+
+func getStorageLabel(storageDetails params.StorageDetails) string {
+	return strings.TrimSuffix(strings.TrimPrefix(storageDetails.StorageTag, "storage-"), "-0")
+}
+
 func (c applicationsClient) ReadApplication(input *ReadApplicationInput) (*ReadApplicationResponse, error) {
 	conn, err := c.GetConnection(&input.ModelName)
 	if err != nil {
@@ -816,9 +886,17 @@ func (c applicationsClient) ReadApplication(input *ReadApplicationInput) (*ReadA
 	appInfo := apps[0].Result
 
 	// TODO: Investigate why we're getting the full status here when
-	// application status is needed.
-	status, err := clientAPIClient.Status(nil)
+	// application status is needed. include storage.
+	status, err := clientAPIClient.Status(&apiclient.StatusArgs{
+		Patterns:       []string{},
+		IncludeStorage: true,
+	})
 	if err != nil {
+		if strings.Contains(err.Error(), "filesystem for storage instance") {
+			// Retry if we get this error. It means the storage is not ready yet.
+			return nil, &storageNotFoundError{input.AppName}
+		}
+		c.Errorf(err, "failed to get status")
 		return nil, err
 	}
 	var appStatus params.ApplicationStatus
@@ -827,6 +905,22 @@ func (c applicationsClient) ReadApplication(input *ReadApplicationInput) (*ReadA
 		return nil, fmt.Errorf("no status returned for application: %s", input.AppName)
 	}
 
+	//// Print Full status
+	//c.Tracef("Full status", map[string]interface{}{"status": status})
+	//
+	//// Get storage info from the full status.
+	//for _, sst := range status.StorageContraints {
+	//	c.Tracef("StorageContraints status", map[string]interface{}{"storage": sst.StorageTag, "kind": sst.Kind})
+	//}
+	//for _, fst := range status.Filesystems {
+	//	c.Tracef("Filesystem status", map[string]interface{}{"storage": fst.StorageContraints.StorageTag, "pool": fst.Info.Pool, "size": fst.Info.Size})
+	//}
+	storages := transformToStorageConstraints(status.Storage, status.Filesystems, status.Volumes)
+	// Print storage to console
+	for k, v := range storages {
+		c.Tracef("StorageContraints constraints", map[string]interface{}{"storage": k, "constraints": v})
+	}
+
 	allocatedMachines := set.NewStrings()
 	for _, v := range appStatus.Units {
 		if v.Machine != "" {
@@ -993,6 +1087,7 @@ func (c applicationsClient) ReadApplication(input *ReadApplicationInput) (*ReadA
 		Principal:        appInfo.Principal,
 		Placement:        placement,
 		EndpointBindings: endpointBindings,
+		Storage:          storages,
 		Resources:        resourceRevisions,
 	}