refact(csi): use common lib-csi imports (#263)

Signed-off-by: shubham <shubham.bajpai@mayadata.io>

vendor/github.com/openebs/lib-csi/pkg/common/env/env.go

@@ -0,0 +1,113 @@
+/*
+Copyright 2019 The OpenEBS 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
+
+    http://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 env
+
+import (
+	"os"
+	"strconv"
+	"strings"
+)
+
+const (
+	// KubeConfig is the ENV variable to fetch kubernetes kubeconfig
+	KubeConfig = "OPENEBS_IO_KUBE_CONFIG"
+
+	// KubeMaster is the ENV variable to fetch kubernetes master's address
+	KubeMaster = "OPENEBS_IO_K8S_MASTER"
+)
+
+// EnvironmentSetter abstracts setting of environment variable
+type EnvironmentSetter func(envKey string, value string) (err error)
+
+// EnvironmentGetter abstracts fetching value from an environment variable
+type EnvironmentGetter func(envKey string) (value string)
+
+// EnvironmentLookup abstracts looking up an environment variable
+type EnvironmentLookup func(envKey string) (value string, present bool)
+
+// Set sets the provided environment variable
+//
+// NOTE:
+//  This is an implementation of EnvironmentSetter
+func Set(envKey string, value string) (err error) {
+	return os.Setenv(string(envKey), value)
+}
+
+// Get fetches value from the provided environment variable
+//
+// NOTE:
+//  This is an implementation of EnvironmentGetter
+func Get(envKey string) (value string) {
+	return getEnv(string(envKey))
+}
+
+// GetOrDefault fetches value from the provided environment variable
+// which on empty returns the defaultValue
+// NOTE: os.Getenv is used here instead of os.LookupEnv because it is
+// not required to know if the environment variable is defined on the system
+func GetOrDefault(e string, defaultValue string) (value string) {
+	envValue := Get(e)
+	if len(envValue) == 0 {
+		// ENV not defined or set to ""
+		return defaultValue
+	}
+	return envValue
+}
+
+// Lookup looks up an environment variable
+//
+// NOTE:
+//  This is an implementation of EnvironmentLookup
+func Lookup(envKey string) (value string, present bool) {
+	return lookupEnv(string(envKey))
+}
+
+// Truthy returns boolean based on the environment variable's value
+//
+// The lookup value can be truthy (i.e. 1, t, TRUE, true) or falsy (0, false,
+// etc) based on strconv.ParseBool logic
+func Truthy(envKey string) (truth bool) {
+	v, found := Lookup(envKey)
+	if !found {
+		return
+	}
+	truth, _ = strconv.ParseBool(v)
+	return
+}
+
+// LookupOrFalse looks up an environment variable and returns a string "false"
+// if environment variable is not present. It returns appropriate values for
+// other cases.
+func LookupOrFalse(envKey string) string {
+	val, present := Lookup(envKey)
+	if !present {
+		return "false"
+	}
+	return strings.TrimSpace(val)
+}
+
+// getEnv fetches the provided environment variable's value
+func getEnv(envKey string) (value string) {
+	return strings.TrimSpace(os.Getenv(envKey))
+}
+
+// lookupEnv looks up the provided environment variable
+func lookupEnv(envKey string) (value string, present bool) {
+	value, present = os.LookupEnv(envKey)
+	value = strings.TrimSpace(value)
+	return
+}

vendor/github.com/openebs/lib-csi/pkg/common/errors/errors.go

@@ -0,0 +1,99 @@
+/*
+Copyright 2019 The OpenEBS 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
+
+    http://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 errors
+
+import (
+	"fmt"
+)
+
+// New returns an error with the supplied message.
+// New also records the stack trace at the point it was called.
+func New(message string) error {
+	return &err{
+		prefix: stackTraceMessagePrefix,
+		msg:    message,
+		stack:  callers(),
+	}
+}
+
+// Errorf formats according to a format specifier and returns the string
+// as a value that satisfies error.
+// Errorf also records the stack trace at the point it was called.
+func Errorf(format string, args ...interface{}) error {
+	return &err{
+		prefix: stackTraceMessagePrefix,
+		msg:    fmt.Sprintf(format, args...),
+		stack:  callers(),
+	}
+}
+
+// Wrap annotates err with a new message.
+// If err is nil, Wrap returns nil.
+func Wrap(err error, message string) error {
+	if err == nil {
+		return nil
+	}
+	return &wrapper{wrapErrorMessagePrefix, message, err}
+}
+
+// Wrapf annotates err with the format specifier.
+// If err is nil, Wrapf returns nil.
+func Wrapf(err error, format string, args ...interface{}) error {
+	if err == nil {
+		return nil
+	}
+	return &wrapper{wrapErrorMessagePrefix, fmt.Sprintf(format, args...), err}
+}
+
+// WithStack annotates err with a stack trace at the
+// point WithStack was called. If err is nil, WithStack returns nil.
+func WithStack(err error) error {
+	if err == nil {
+		return nil
+	}
+	return &withStack{
+		stackTraceMessagePrefix,
+		err,
+		callers(),
+	}
+}
+
+// Cause returns the underlying cause of the error, if possible.
+// An error value has a cause if it implements the following
+// interface:
+//
+//     type causer interface {
+//            Cause() error
+//     }
+//
+// If the error does not implement Cause, the original error will
+// be returned. If the error is nil, nil will be returned without further
+// investigation.
+func Cause(err error) error {
+	type causer interface {
+		Cause() error
+	}
+
+	for err != nil {
+		cause, ok := err.(causer)
+		if !ok {
+			break
+		}
+		err = cause.Cause()
+	}
+	return err
+}

vendor/github.com/openebs/lib-csi/pkg/common/errors/types.go

@@ -0,0 +1,188 @@
+/*
+Copyright 2019 The OpenEBS 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
+
+    http://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 errors
+
+import (
+	"fmt"
+	"runtime"
+
+	"github.com/pkg/errors"
+)
+
+const (
+	wrapErrorMessagePrefix  string = "  --  "
+	listErrorMessagePrefix  string = "  -  "
+	stackTraceMessagePrefix string = "      "
+)
+
+// stack represents a stack of program counters.
+type stack []uintptr
+
+// callers returns stack of caller function
+func callers() *stack {
+	const depth = 32
+	var pcs [depth]uintptr
+	n := runtime.Callers(3, pcs[:])
+	var st stack = pcs[0:n]
+	return &st
+}
+
+// err implements error interface that has a message and stack
+type err struct {
+	prefix string
+	msg    string
+	*stack
+}
+
+// Error is implementation of error interface
+func (e *err) Error() string { return e.msg }
+
+// Format is implementation of Formater interface
+func (e *err) Format(s fmt.State, verb rune) {
+	message := wrapErrorMessagePrefix + e.msg
+	switch verb {
+	case 'v':
+		if s.Flag('+') {
+			fmt.Fprint(s, message)
+			for i, pc := range *e.stack {
+				if i > 0 {
+					return
+				}
+				f := errors.Frame(pc)
+				fmt.Fprintf(s, "\n%s%+v", e.prefix, f)
+			}
+			return
+		}
+		fallthrough
+	case 's', 'q':
+		fmt.Fprint(s, message)
+	}
+}
+
+// wrapper implements error interface that has a message and error
+type wrapper struct {
+	prefix string
+	msg    string
+	error
+}
+
+// Error is implementation of error interface
+func (w *wrapper) Error() string { return w.msg }
+
+// Cause is implementation of causer interface
+func (w *wrapper) Cause() error { return w.error }
+
+// Format is implementation of Formater interface
+func (w *wrapper) Format(s fmt.State, verb rune) {
+	switch verb {
+	case 'v':
+		if s.Flag('+') {
+			fmt.Fprintf(s, "%+v\n", w.error)
+			fmt.Fprint(s, w.prefix+w.msg)
+			return
+		}
+		fallthrough
+	case 's', 'q':
+		fmt.Fprintf(s, "%s\n", w.error)
+		fmt.Fprint(s, w.prefix+w.msg)
+	}
+}
+
+// withStack implements error interface that has a stack and error
+type withStack struct {
+	prefix string
+	error
+	*stack
+}
+
+// Format is implementation of Formater interface
+func (ws *withStack) Format(s fmt.State, verb rune) {
+	message := wrapErrorMessagePrefix + fmt.Sprintf("%s", ws.error)
+	switch verb {
+	case 'v':
+		if s.Flag('+') {
+			fmt.Fprint(s, message)
+			for i, pc := range *ws.stack {
+				if i > 0 {
+					return
+				}
+				f := errors.Frame(pc)
+				fmt.Fprintf(s, "\n%s%+v", ws.prefix, f)
+			}
+			return
+		}
+		fallthrough
+	case 's', 'q':
+		fmt.Fprint(s, message)
+	}
+}
+
+// Cause is implementation of causer interface
+func (ws *withStack) Cause() error { return ws.error }
+
+// ErrorList is a wrapper over list of errors
+// It implements error interface
+type ErrorList struct {
+	Errors []error
+	msg    string
+}
+
+// Error is implementation of error interface
+func (el *ErrorList) Error() string {
+	message := ""
+	for _, err := range el.Errors {
+		message += err.Error() + ":"
+	}
+	el.msg = message
+	return message
+}
+
+// Format is implementation of Formater interface
+func (el *ErrorList) Format(s fmt.State, verb rune) {
+	message := ""
+	for _, err := range el.Errors {
+		message += "\n" + listErrorMessagePrefix + err.Error()
+	}
+	fmt.Fprint(s, message)
+
+}
+
+// WithStack annotates ErrorList with a new message and
+// stack trace of caller.
+func (el *ErrorList) WithStack(message string) error {
+	if el == nil {
+		return nil
+	}
+	return &withStack{
+		stackTraceMessagePrefix,
+		Wrap(el, message),
+		callers(),
+	}
+}
+
+// WithStackf annotates ErrorList with the format specifier
+// and stack trace of caller.
+func (el *ErrorList) WithStackf(format string, args ...interface{}) error {
+	if el == nil {
+		return nil
+	}
+	return &withStack{
+		stackTraceMessagePrefix,
+		Wrapf(el, format, args...),
+		callers(),
+	}
+}

vendor/github.com/openebs/lib-csi/pkg/common/helpers/helpers.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2020 The OpenEBS 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
+
+    http://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 helpers
+
+import (
+	"strings"
+)
+
+// GetCaseInsensitiveMap coercs the map's keys to lower case, which only works
+// when unicode char is in ASCII subset. May overwrite key-value pairs on
+// different permutations of key case as in Key and key. DON'T force values to the
+// lower case unconditionally, because values for keys such as mountpoint or
+// keylocation are case-sensitive.
+// Note that although keys such as 'comPREssion' are accepted and processed,
+// even if they are technically invalid, updates to rectify such typing will be
+// prohibited as a forbidden update.
+func GetCaseInsensitiveMap(dict *map[string]string) map[string]string {
+	insensitiveDict := map[string]string{}
+
+	for k, v := range *dict {
+		insensitiveDict[strings.ToLower(k)] = v
+	}
+	return insensitiveDict
+}
+
+// GetInsensitiveParameter handles special case ofGetCaseInsensitiveMap looking up one
+// key-value pair only
+func GetInsensitiveParameter(dict *map[string]string, key string) string {
+	insensitiveDict := GetCaseInsensitiveMap(dict)
+	return insensitiveDict[strings.ToLower(key)]
+}

vendor/github.com/openebs/lib-csi/pkg/common/kubernetes/client/client.go

@@ -0,0 +1,250 @@
+/*
+Copyright 2019 The OpenEBS 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
+
+    http://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 client
+
+import (
+	"strings"
+	"sync"
+
+	env "github.com/openebs/lib-csi/pkg/common/env"
+	"github.com/pkg/errors"
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+// getInClusterConfigFunc abstracts the logic to get
+// kubernetes incluster config
+//
+// NOTE:
+//  typed function makes it simple to mock
+type getInClusterConfigFunc func() (*rest.Config, error)
+
+// buildConfigFromFlagsFunc provides the abstraction to get
+// kubernetes config from provided flags
+//
+// NOTE:
+//  typed function makes it simple to mock
+type buildConfigFromFlagsFunc func(string, string) (*rest.Config, error)
+
+// GetConfigFunc provides the abstraction to get
+// kubernetes config from provided client instance
+//
+// NOTE:
+//  typed function makes it simple to mock
+type GetConfigFunc func(*Client) (*rest.Config, error)
+
+// GetConfig returns kubernetes config instance
+//
+// NOTE:
+//  This is an implementation of GetConfigFunc
+func GetConfig(c *Client) (*rest.Config, error) {
+	if c == nil {
+		return nil, errors.New("failed to get kubernetes config: nil client was provided")
+	}
+	return c.GetConfigForPathOrDirect()
+}
+
+// getKubeMasterIPFunc provides the abstraction to get
+// kubernetes master IP address
+//
+// NOTE:
+//  typed function makes it simple to mock
+type getKubeMasterIPFunc func(string) string
+
+// getKubeConfigPathFunc provides the abstraction to get
+// kubernetes config path
+//
+// NOTE:
+//  typed function makes it simple to mock
+type getKubeConfigPathFunc func(string) string
+
+// getKubernetesDynamicClientFunc provides the abstraction to get
+// dynamic kubernetes clientset
+//
+// NOTE:
+//  typed function makes it simple to mock
+type getKubernetesDynamicClientFunc func(*rest.Config) (dynamic.Interface, error)
+
+// getKubernetesClientsetFunc provides the abstraction to get
+// kubernetes clientset
+//
+// NOTE:
+//  typed function makes it simple to mock
+type getKubernetesClientsetFunc func(*rest.Config) (*kubernetes.Clientset, error)
+
+// Client provides common kuberenetes client operations
+type Client struct {
+	IsInCluster    bool   // flag to let client point to its own cluster
+	KubeConfigPath string // kubeconfig path to get kubernetes clientset
+
+	// Below functions are useful during mock
+
+	// handle to get in cluster config
+	getInClusterConfig getInClusterConfigFunc
+
+	// handle to get desired kubernetes config
+	buildConfigFromFlags buildConfigFromFlagsFunc
+
+	// handle to get kubernetes clienset
+	getKubernetesClientset getKubernetesClientsetFunc
+
+	// handle to get dynamic kubernetes clientset
+	getKubernetesDynamicClient getKubernetesDynamicClientFunc
+
+	// handle to get kubernetes master IP
+	getKubeMasterIP getKubeMasterIPFunc
+
+	// handle to get kubernetes config path
+	getKubeConfigPath getKubeConfigPathFunc
+}
+
+// OptionFunc is a typed function that abstracts any kind of operation
+// against the provided client instance
+//
+// This is the basic building block to create functional operations
+// against the client instance
+type OptionFunc func(*Client)
+
+// New returns a new instance of client
+func New(opts ...OptionFunc) *Client {
+	c := &Client{}
+	for _, o := range opts {
+		o(c)
+	}
+	withDefaults(c)
+	return c
+}
+
+var (
+	instance *Client
+	once     sync.Once
+)
+
+// Instance returns a singleton instance of
+// this client
+func Instance(opts ...OptionFunc) *Client {
+	once.Do(func() {
+		instance = New(opts...)
+	})
+
+	return instance
+}
+
+func withDefaults(c *Client) {
+	if c.getInClusterConfig == nil {
+		c.getInClusterConfig = rest.InClusterConfig
+	}
+	if c.buildConfigFromFlags == nil {
+		c.buildConfigFromFlags = clientcmd.BuildConfigFromFlags
+	}
+	if c.getKubernetesClientset == nil {
+		c.getKubernetesClientset = kubernetes.NewForConfig
+	}
+	if c.getKubernetesDynamicClient == nil {
+		c.getKubernetesDynamicClient = dynamic.NewForConfig
+	}
+	if c.getKubeMasterIP == nil {
+		c.getKubeMasterIP = env.Get
+	}
+	if c.getKubeConfigPath == nil {
+		c.getKubeConfigPath = env.Get
+	}
+}
+
+// InCluster enables IsInCluster flag
+func InCluster() OptionFunc {
+	return func(c *Client) {
+		c.IsInCluster = true
+	}
+}
+
+// WithKubeConfigPath sets kubeconfig path
+// against this client instance
+func WithKubeConfigPath(kubeConfigPath string) OptionFunc {
+	return func(c *Client) {
+		c.KubeConfigPath = kubeConfigPath
+	}
+}
+
+// Clientset returns a new instance of kubernetes clientset
+func (c *Client) Clientset() (*kubernetes.Clientset, error) {
+	config, err := c.GetConfigForPathOrDirect()
+	if err != nil {
+		return nil, errors.Wrapf(err,
+			"failed to get kubernetes clientset: failed to get kubernetes config: IsInCluster {%t}: KubeConfigPath {%s}",
+			c.IsInCluster,
+			c.KubeConfigPath,
+		)
+	}
+	return c.getKubernetesClientset(config)
+}
+
+// Config returns the kubernetes config instance based on available criteria
+func (c *Client) Config() (config *rest.Config, err error) {
+	// IsInCluster flag holds the top most priority
+	if c.IsInCluster {
+		return c.getInClusterConfig()
+	}
+
+	// ENV holds second priority
+	if strings.TrimSpace(c.getKubeMasterIP(env.KubeMaster)) != "" ||
+		strings.TrimSpace(c.getKubeConfigPath(env.KubeConfig)) != "" {
+		return c.getConfigFromENV()
+	}
+
+	// Defaults to InClusterConfig
+	return c.getInClusterConfig()
+}
+
+// ConfigForPath returns the kubernetes config instance based on KubeConfig path
+func (c *Client) ConfigForPath(kubeConfigPath string) (config *rest.Config, err error) {
+	return c.buildConfigFromFlags("", kubeConfigPath)
+}
+
+// GetConfigForPathOrDirect returns the kubernetes config instance based on direct KubeConfig
+func (c *Client) GetConfigForPathOrDirect() (config *rest.Config, err error) {
+	if c.KubeConfigPath != "" {
+		return c.ConfigForPath(c.KubeConfigPath)
+	}
+	return c.Config()
+}
+
+func (c *Client) getConfigFromENV() (config *rest.Config, err error) {
+	k8sMaster := c.getKubeMasterIP(env.KubeMaster)
+	kubeConfig := c.getKubeConfigPath(env.KubeConfig)
+	if strings.TrimSpace(k8sMaster) == "" &&
+		strings.TrimSpace(kubeConfig) == "" {
+		return nil, errors.Errorf(
+			"failed to get kubernetes config: missing ENV: atleast one should be set: {%s} or {%s}",
+			env.KubeMaster,
+			env.KubeConfig,
+		)
+	}
+	return c.buildConfigFromFlags(k8sMaster, kubeConfig)
+}
+
+// Dynamic returns a kubernetes dynamic client capable of invoking operations
+// against kubernetes resources
+func (c *Client) Dynamic() (dynamic.Interface, error) {
+	config, err := c.GetConfigForPathOrDirect()
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to get dynamic client")
+	}
+	return c.getKubernetesDynamicClient(config)
+}