feat(analytics): adding google analytics for ZFSPV

Whenever a volume is provisioned and de-provisioned we will send a google event with mainly following details :
1.    pvName (will shown as app title in google analytics)
2.    size of the volume
3.    event type : volume-provision, volume-deprovision
4.    storage type zfs-localpv
5.    replicacount as 1
6.    ClientId as default namespace uuid

Apart from this, we send the event once in 24 hr, which will have some info like number of nodes, node type, kubernetes version etc.

This metric is cotrolled by OPENEBS_IO_ENABLE_ANALYTICS env. We can set it to false if we don't want to send the metrics.

Signed-off-by: Pawan <pawan@mayadata.io>

pkg/usage/usage.go

@@ -0,0 +1,257 @@
+/*
+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 usage
+
+import (
+	k8sapi "github.com/openebs/zfs-localpv/pkg/client/k8s/v1alpha1"
+)
+
+// Usage struct represents all information about a usage metric sent to
+// Google Analytics with respect to the application
+type Usage struct {
+	// Embedded Event struct as we are currently only sending hits of type
+	// 'event'
+	Event
+
+	// https://developers.google.com/analytics/devguides/collection/protocol/v1/parameters#an
+	// use-case: cstor or jiva volume, or m-apiserver application
+	// Embedded field for application
+	Application
+
+	// Embedded Gclient struct
+	Gclient
+}
+
+// Event is a represents usage of OpenEBS
+// Event contains all the query param fields when hits is of type='event'
+// Ref: https://developers.google.com/analytics/devguides/collection/protocol/v1/parameters#ec
+type Event struct {
+	// (Required) Event Category, ec
+	category string
+	// (Required) Event Action, ea
+	action string
+	// (Optional) Event Label, el
+	label string
+	// (Optional) Event vallue, ev
+	// Non negative
+	value int64
+}
+
+// NewEvent returns an Event struct with eventCategory, eventAction,
+// eventLabel, eventValue fields
+func (u *Usage) NewEvent(c, a, l string, v int64) *Usage {
+	u.category = c
+	u.action = a
+	u.label = l
+	u.value = v
+	return u
+}
+
+// Application struct holds details about the Application
+type Application struct {
+	// eg. project version
+	appVersion string
+
+	// eg. kubernetes version
+	appInstallerID string
+
+	// Name of the application, usage(OpenEBS/NDM)
+	appID string
+
+	// eg. usage(os-type/architecture) of system or volume's CASType
+	appName string
+}
+
+// Gclient struct represents a Google Analytics hit
+type Gclient struct {
+	// constant tracking-id used to send a hit
+	trackID string
+
+	// anonymous client-id
+	clientID string
+
+	// anonymous campaign source
+	campaignSource string
+
+	// https://developers.google.com/analytics/devguides/collection/protocol/v1/parameters#ds
+	// (usecase) node-detail
+	dataSource string
+
+	// Document-title property in Google Analytics
+	// https://developers.google.com/analytics/devguides/collection/protocol/v1/parameters#dt
+	// use-case: uuid of the volume objects or a uuid to anonymously tell objects apart
+	documentTitle string
+}
+
+// New returns an instance of Usage
+func New() *Usage {
+	return &Usage{}
+}
+
+// SetDataSource : usage(os-type, kernel)
+func (u *Usage) SetDataSource(dataSource string) *Usage {
+	u.dataSource = dataSource
+	return u
+}
+
+// SetTrackingID Sets the GA-code for the project
+func (u *Usage) SetTrackingID(track string) *Usage {
+	u.trackID = track
+	return u
+}
+
+// SetCampaignSource : source of openebs installater like:
+// helm or operator etc. This will have to be configured
+// via ENV variable OPENEBS_IO_INSTALLER_TYPE
+func (u *Usage) SetCampaignSource(campaignSrc string) *Usage {
+	u.campaignSource = campaignSrc
+	return u
+}
+
+// SetDocumentTitle : usecase(anonymous-id)
+func (u *Usage) SetDocumentTitle(documentTitle string) *Usage {
+	u.documentTitle = documentTitle
+	return u
+}
+
+// SetApplicationName : usecase(os-type/arch, volume CASType)
+func (u *Usage) SetApplicationName(appName string) *Usage {
+	u.appName = appName
+	return u
+}
+
+// SetApplicationID : usecase(OpenEBS/NDM)
+func (u *Usage) SetApplicationID(appID string) *Usage {
+	u.appID = appID
+	return u
+}
+
+// SetApplicationVersion : usecase(project-version)
+func (u *Usage) SetApplicationVersion(appVersion string) *Usage {
+	u.appVersion = appVersion
+	return u
+}
+
+// SetApplicationInstallerID : usecase(k8s-version)
+func (u *Usage) SetApplicationInstallerID(appInstallerID string) *Usage {
+	u.appInstallerID = appInstallerID
+	return u
+}
+
+// SetClientID sets the anonymous user id
+func (u *Usage) SetClientID(userID string) *Usage {
+	u.clientID = userID
+	return u
+}
+
+// SetCategory sets the category of an event
+func (u *Usage) SetCategory(c string) *Usage {
+	u.category = c
+	return u
+}
+
+// SetAction sets the action of an event
+func (u *Usage) SetAction(a string) *Usage {
+	u.action = a
+	return u
+}
+
+// SetLabel sets the label for an event
+func (u *Usage) SetLabel(l string) *Usage {
+	u.label = l
+	return u
+}
+
+// SetValue sets the value for an event's label
+func (u *Usage) SetValue(v int64) *Usage {
+	u.value = v
+	return u
+}
+
+// Build is a builder method for Usage struct
+func (u *Usage) Build() *Usage {
+	// Default ApplicationID for openebs project is OpenEBS
+	v := NewVersion()
+	v.getVersion(false)
+	u.SetApplicationID(AppName).
+		SetTrackingID(GAclientID).
+		SetClientID(v.id).
+		SetCampaignSource(v.installerType)
+	// TODO: Add condition for version over-ride
+	// Case: CAS/Jiva version, etc
+	return u
+}
+
+// Application builder is used for adding k8s&openebs environment detail
+// for non install events
+func (u *Usage) ApplicationBuilder() *Usage {
+	v := NewVersion()
+	v.getVersion(false)
+	u.SetApplicationVersion(v.openebsVersion).
+		SetApplicationName(v.k8sArch).
+		SetApplicationInstallerID(v.k8sVersion).
+		SetDataSource(v.nodeType)
+	return u
+}
+
+// SetVolumeCapacity sets the storage capacity of the volume for a volume event
+func (u *Usage) SetVolumeCapacity(volCapG string) *Usage {
+	s, _ := toGigaUnits(volCapG)
+	u.SetValue(s)
+	return u
+}
+
+// Wrapper for setting the default storage-engine for volume-provision event
+func (u *Usage) SetVolumeType(volType, method string) *Usage {
+	if method == VolumeProvision && volType == "" {
+		// Set the default storage engine, if not specified in the request
+		u.SetApplicationName(DefaultCASType)
+	} else {
+		u.SetApplicationName(volType)
+	}
+	return u
+}
+
+// Wrapper for setting replica count for volume events
+// NOTE: This doesn't get the replica count in a volume de-provision event.
+// TODO: Pick the current value of replica-count from the CAS-engine
+func (u *Usage) SetReplicaCount(count, method string) *Usage {
+	if method == VolumeProvision && count == "" {
+		// Case: When volume-provision the replica count isn't specified
+		// it is set to three by default by the m-apiserver
+		u.SetAction(DefaultReplicaCount)
+	} else {
+		// Catch all case for volume-deprovision event and
+		// volume-provision event with an overriden replica-count
+		u.SetAction(Replica + count)
+	}
+	return u
+}
+
+// InstallBuilder is a concrete builder for install events
+func (u *Usage) InstallBuilder(override bool) *Usage {
+	v := NewVersion()
+	clusterSize, _ := k8sapi.NumberOfNodes()
+	v.getVersion(override)
+	u.SetApplicationVersion(v.openebsVersion).
+		SetApplicationName(v.k8sArch).
+		SetApplicationInstallerID(v.k8sVersion).
+		SetDataSource(v.nodeType).
+		SetDocumentTitle(v.id).
+		SetApplicationID(AppName).
+		NewEvent(InstallEvent, RunningStatus, EventLabelNode, int64(clusterSize))
+	return u
+}