feat(get): add code to get resource (#176)

Signed-off-by: Amit Bhatt <[email protected]>

Author: amitbhatt818

pkg/recipe/get.go

@@ -0,0 +1,126 @@
+/*
+Copyright 2020 The MayaData Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package recipe
+
+import (
+	"fmt"
+
+	"github.com/pkg/errors"
+	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	types "mayadata.io/d-operators/types/recipe"
+)
+
+// Gettable helps fetching desired state from the cluster
+type Gettable struct {
+	BaseRunner
+	Get *types.Get
+
+	result *types.GetResult
+	err    error
+}
+
+// GettableConfig helps in creating new instance of Gettable
+type GettableConfig struct {
+	BaseRunner
+	Get *types.Get
+}
+
+// NewGetter returns a new instance of Gettable
+func NewGetter(config GettableConfig) *Gettable {
+	return &Gettable{
+		BaseRunner: config.BaseRunner,
+		Get:        config.Get,
+		result:     &types.GetResult{},
+	}
+}
+
+func (g *Gettable) getCRD() (*types.GetResult, error) {
+	var crd *v1beta1.CustomResourceDefinition
+	err := UnstructToTyped(g.Get.State, &crd)
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"Failed to transform unstruct instance to crd equivalent",
+		)
+	}
+	// use crd client to get crds
+	obj, err := g.crdClient.
+		CustomResourceDefinitions().
+		Get(g.Get.State.GetName(), metav1.GetOptions{})
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"Failed to get crd %q",
+			g.Get.State.GetName(),
+		)
+	}
+	return &types.GetResult{
+		Phase: types.GetStatusPassed,
+		Message: fmt.Sprintf(
+			"Get CRD: Kind %s: APIVersion %s: Name %s",
+			crd.Spec.Names.Singular,
+			crd.Spec.Group+"/"+crd.Spec.Version,
+			g.Get.State.GetName(),
+		),
+		V1Beta1CRD: obj,
+	}, nil
+}
+
+func (g *Gettable) getResource() (*types.GetResult, error) {
+	var message = fmt.Sprintf(
+		"Get resource with %s / %s: GVK %s",
+		g.Get.State.GetNamespace(),
+		g.Get.State.GetName(),
+		g.Get.State.GroupVersionKind(),
+	)
+	client, err := g.GetClientForAPIVersionAndKind(
+		g.Get.State.GetAPIVersion(),
+		g.Get.State.GetKind(),
+	)
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"Failed to get resource client",
+		)
+	}
+	obj, err := client.
+		Namespace(g.Get.State.GetNamespace()).
+		Get(g.Get.State.GetName(), metav1.GetOptions{})
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"Failed to get resource",
+		)
+	}
+	return &types.GetResult{
+		Phase:   types.GetStatusPassed,
+		Message: message,
+		Object:  obj,
+	}, nil
+}
+
+// Run executes applying the desired state against the
+// cluster
+func (g *Gettable) Run() (*types.GetResult, error) {
+	if g.Get.State.GetKind() == "CustomResourceDefinition" {
+		// get CRD
+		return g.getCRD()
+	}
+	return g.getResource()
+}

types/recipe/get.go

@@ -0,0 +1,84 @@
+/*
+Copyright 2020 The MayaData Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package types
+
+import (
+	"encoding/json"
+
+	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+)
+
+// Get represents the desired state that needs to
+// be fetched from the cluster
+type Get struct {
+	// Desired state that needs to be fetched from the
+	// Kubernetes cluster
+	State *unstructured.Unstructured `json:"state"`
+}
+
+// String implements the Stringer interface
+func (g Get) String() string {
+	raw, err := json.MarshalIndent(
+		g,
+		" ",
+		".",
+	)
+	if err != nil {
+		panic(err)
+	}
+	return string(raw)
+}
+
+// GetStatusPhase is a typed definition to determine the
+// result of executing a get invocation
+type GetStatusPhase string
+
+const (
+	// GetStatusPassed defines a successful get
+	GetStatusPassed GetStatusPhase = "Passed"
+
+	// GetStatusWarning defines a get that resulted in warnings
+	GetStatusWarning GetStatusPhase = "Warning"
+
+	// GetStatusFailed defines a failed get
+	GetStatusFailed GetStatusPhase = "Failed"
+)
+
+// ToTaskStatusPhase transforms GetStatusPhase to TaskStatusPhase
+func (phase GetStatusPhase) ToTaskStatusPhase() TaskStatusPhase {
+	switch phase {
+	case GetStatusPassed:
+		return TaskStatusPassed
+	case GetStatusFailed:
+		return TaskStatusFailed
+	case GetStatusWarning:
+		return TaskStatusWarning
+	default:
+		return ""
+	}
+}
+
+// GetResult holds the result of the get operation
+type GetResult struct {
+	Phase      GetStatusPhase                    `json:"phase"`
+	Message    string                            `json:"message,omitempty"`
+	Verbose    string                            `json:"verbose,omitempty"`
+	Warning    string                            `json:"warning,omitempty"`
+	V1Beta1CRD *v1beta1.CustomResourceDefinition `json:"v1b1CRD,omitempty"`
+	Object     *unstructured.Unstructured        `json:"object,omitempty"`
+}