mgr-JobPartMgr.go

package ste

import (
	"context"
	"errors"
	"fmt"
	"net"
	"net/http"
	"os"
	"strings"
	"sync/atomic"
	"time"

	"github.com/Azure/azure-pipeline-go/pipeline"
	"github.com/Azure/azure-storage-azcopy/azbfs"
	"github.com/Azure/azure-storage-azcopy/common"
	"github.com/Azure/azure-storage-blob-go/2018-03-28/azblob"
	"github.com/Azure/azure-storage-file-go/2017-07-29/azfile"
	"github.com/Azure/go-autorest/autorest/adal"
)

var _ IJobPartMgr = &jobPartMgr{}

type IJobPartMgr interface {
	Plan() *JobPartPlanHeader
	ScheduleTransfers(jobCtx context.Context)
	StartJobXfer(jptm IJobPartTransferMgr)
	ReportTransferDone() uint32
	IsForceWriteTrue() bool
	ScheduleChunks(chunkFunc chunkFunc)
	RescheduleTransfer(jptm IJobPartTransferMgr)
	BlobTiers() (blockBlobTier common.BlockBlobTier, pageBlobTier common.PageBlobTier)
	SAS() (string, string)
	//CancelJob()
	Close()
	// TODO: added for debugging purpose. remove later
	OccupyAConnection()
	// TODO: added for debugging purpose. remove later
	ReleaseAConnection()
	common.ILogger
}

type serviceAPIVersionOverride struct{}

// ServiceAPIVersionOverride is a global variable in package ste which is a key to Service Api Version Value set in the every Job's context.
var ServiceAPIVersionOverride = serviceAPIVersionOverride{}

// DefaultServiceApiVersion is the default value of service api version that is set as value to the ServiceAPIVersionOverride in every Job's context.
const DefaultServiceApiVersion = "2018-03-28"

// NewVersionPolicy creates a factory that can override the service version
// set in the request header.
// If the context has key overwrite-current-version set to false, then x-ms-version in
// request is not overwritten else it will set x-ms-version to 207-04-17
func NewVersionPolicyFactory() pipeline.Factory {
	return pipeline.FactoryFunc(func(next pipeline.Policy, po *pipeline.PolicyOptions) pipeline.PolicyFunc {
		return func(ctx context.Context, request pipeline.Request) (pipeline.Response, error) {
			// get the service api version value using the ServiceAPIVersionOverride set in the context.
			if value := ctx.Value(ServiceAPIVersionOverride); value != nil {
				request.Header.Set("x-ms-version", value.(string))
			}
			resp, err := next.Do(ctx, request)
			return resp, err
		}
	})
}

func newAzcopyHTTPClient() *http.Client {
	return &http.Client{
		Transport: &http.Transport{
			Proxy: http.ProxyFromEnvironment,
			// We use Dial instead of DialContext as DialContext has been reported to cause slower performance.
			Dial /*Context*/ : (&net.Dialer{
				Timeout:   30 * time.Second,
				KeepAlive: 30 * time.Second,
				DualStack: true,
			}).Dial, /*Context*/
			MaxIdleConns:           0, // No limit
			MaxIdleConnsPerHost:    1000,
			IdleConnTimeout:        180 * time.Second,
			TLSHandshakeTimeout:    10 * time.Second,
			ExpectContinueTimeout:  1 * time.Second,
			DisableKeepAlives:      false,
			DisableCompression:     false,
			MaxResponseHeaderBytes: 0,
			//ResponseHeaderTimeout:  time.Duration{},
			//ExpectContinueTimeout:  time.Duration{},
		},
	}
}

// newAzcopyHTTPClientFactory creates a HTTPClientPolicyFactory object that sends HTTP requests to a Go's default http.Client.
func newAzcopyHTTPClientFactory(pipelineHTTPClient *http.Client) pipeline.Factory {
	return pipeline.FactoryFunc(func(next pipeline.Policy, po *pipeline.PolicyOptions) pipeline.PolicyFunc {
		return func(ctx context.Context, request pipeline.Request) (pipeline.Response, error) {
			r, err := pipelineHTTPClient.Do(request.WithContext(ctx))
			if err != nil {
				err = pipeline.NewError(err, "HTTP request failed")
			}
			return pipeline.NewHTTPResponse(r), err
		}
	})
}

// NewBlobPipeline creates a Pipeline using the specified credentials and options.
func NewBlobPipeline(c azblob.Credential, o azblob.PipelineOptions, r XferRetryOptions, p *pacer) pipeline.Pipeline {
	if c == nil {
		panic("c can't be nil")
	}
	// Closest to API goes first; closest to the wire goes last
	f := []pipeline.Factory{
		azblob.NewTelemetryPolicyFactory(o.Telemetry),
		azblob.NewUniqueRequestIDPolicyFactory(),
		NewBlobXferRetryPolicyFactory(r),
		c,
		pipeline.MethodFactoryMarker(), // indicates at what stage in the pipeline the method factory is invoked
		//NewPacerPolicyFactory(p),
		NewVersionPolicyFactory(),
		azblob.NewRequestLogPolicyFactory(o.RequestLog),
	}
	return pipeline.NewPipeline(f, pipeline.Options{HTTPSender: newAzcopyHTTPClientFactory(newAzcopyHTTPClient()), Log: o.Log})
}

// NewBlobFSPipeline creates a pipeline for transfers to and from BlobFS Service
// The blobFS operations currently in azcopy are supported by SharedKey Credentials
func NewBlobFSPipeline(c azbfs.Credential, o azbfs.PipelineOptions, r XferRetryOptions, p *pacer) pipeline.Pipeline {
	if c == nil {
		panic("c can't be nil")
	}
	// Closest to API goes first; closest to the wire goes last
	f := []pipeline.Factory{
		azbfs.NewTelemetryPolicyFactory(o.Telemetry),
		azbfs.NewUniqueRequestIDPolicyFactory(),
		NewBFSXferRetryPolicyFactory(r),
	}

	f = append(f, c)

	f = append(f,
		pipeline.MethodFactoryMarker(), // indicates at what stage in the pipeline the method factory is invoked
		NewPacerPolicyFactory(p),
		azbfs.NewRequestLogPolicyFactory(o.RequestLog))

	return pipeline.NewPipeline(f, pipeline.Options{HTTPSender: newAzcopyHTTPClientFactory(newAzcopyHTTPClient()), Log: o.Log})
}

// newFilePipeline creates a Pipeline using the specified credentials and options.
func newFilePipeline(c azfile.Credential, o azfile.PipelineOptions, r azfile.RetryOptions, p *pacer) pipeline.Pipeline {
	if c == nil {
		panic("c can't be nil")
	}
	// Closest to API goes first; closest to the wire goes last
	f := []pipeline.Factory{
		azfile.NewTelemetryPolicyFactory(o.Telemetry),
		azfile.NewUniqueRequestIDPolicyFactory(),
		azfile.NewRetryPolicyFactory(r),
		c,
		pipeline.MethodFactoryMarker(), // indicates at what stage in the pipeline the method factory is invoked
		NewPacerPolicyFactory(p),
		NewVersionPolicyFactory(),
		azfile.NewRequestLogPolicyFactory(o.RequestLog),
	}
	return pipeline.NewPipeline(f, pipeline.Options{HTTPSender: newAzcopyHTTPClientFactory(newAzcopyHTTPClient()), Log: o.Log})
}

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

// jobPartMgr represents the runtime information for a Job's Part
type jobPartMgr struct {
	// These fields represent the part's existence
	jobMgr   IJobMgr // Refers to this part's Job (for logging, cancelling, etc.)
	filename JobPartPlanFileName

	// sourceSAS defines the sas of the source of the Job. If the source is local Location, then sas is empty.
	// Since sas is not persisted in JobPartPlan file, it stripped from the source and stored in memory in JobPart Manager
	sourceSAS string
	// destinationSAS defines the sas of the destination of the Job. If the destination is local Location, then sas is empty.
	// Since sas is not persisted in JobPartPlan file, it stripped from the destination and stored in memory in JobPart Manager
	destinationSAS string

	// When the part is schedule to run (inprogress), the below fields are used
	planMMF *JobPartPlanMMF // This Job part plan's MMF

	// Additional data shared by all of this Job Part's transfers; initialized when this jobPartMgr is created
	blobHTTPHeaders azblob.BlobHTTPHeaders
	fileHTTPHeaders azfile.FileHTTPHeaders

	// Additional data shared by all of this Job Part's transfers; initialized when this jobPartMgr is created
	blockBlobTier common.BlockBlobTier

	// Additional data shared by all of this Job Part's transfers; initialized when this jobPartMgr is created
	pageBlobTier common.PageBlobTier

	blobMetadata azblob.Metadata
	fileMetadata azfile.Metadata

	preserveLastModifiedTime bool

	newJobXfer newJobXfer // Method used to start the transfer

	priority common.JobPriority

	pacer *pacer // Pacer used by chunks when uploading data

	pipeline pipeline.Pipeline // ordered list of Factory objects and an object implementing the HTTPSender interface

	// numberOfTransfersDone_doNotUse represents the number of transfer of JobPartOrder
	// which are either completed or failed
	// numberOfTransfersDone_doNotUse determines the final cancellation of JobPartOrder
	atomicTransfersDone uint32
}

func (jpm *jobPartMgr) Plan() *JobPartPlanHeader { return jpm.planMMF.Plan() }

// ScheduleTransfers schedules this job part's transfers. It is called when a new job part is ordered & is also called to resume a paused Job
func (jpm *jobPartMgr) ScheduleTransfers(jobCtx context.Context) {
	jpm.atomicTransfersDone = 0 // Reset the # of transfers done back to 0
	// partplan file is opened and mapped when job part is added
	//jpm.planMMF = jpm.filename.Map() // Open the job part plan file & memory-map it in
	plan := jpm.planMMF.Plan()
	// get the list of include / exclude transfers
	includeTransfer, excludeTransfer := jpm.jobMgr.IncludeExclude()
	// *** Open the job part: process any job part plan-setting used by all transfers ***
	dstData := plan.DstBlobData

	jpm.blobHTTPHeaders = azblob.BlobHTTPHeaders{
		ContentType:     string(dstData.ContentType[:dstData.ContentTypeLength]),
		ContentEncoding: string(dstData.ContentEncoding[:dstData.ContentEncodingLength]),
	}

	jpm.blockBlobTier = dstData.BlockBlobTier
	jpm.pageBlobTier = dstData.PageBlobTier
	jpm.fileHTTPHeaders = azfile.FileHTTPHeaders{
		ContentType:     string(dstData.ContentType[:dstData.ContentTypeLength]),
		ContentEncoding: string(dstData.ContentEncoding[:dstData.ContentEncodingLength]),
	}
	// For this job part, split the metadata string apart and create an azblob.Metadata out of it
	metadataString := string(dstData.Metadata[:dstData.MetadataLength])
	jpm.blobMetadata = azblob.Metadata{}
	if len(metadataString) > 0 {
		for _, keyAndValue := range strings.Split(metadataString, ";") { // key/value pairs are separated by ';'
			kv := strings.Split(keyAndValue, "=") // key/value are separated by '='
			jpm.blobMetadata[kv[0]] = kv[1]
		}
	}

	jpm.fileMetadata = azfile.Metadata{}
	if len(metadataString) > 0 {
		for _, keyAndValue := range strings.Split(metadataString, ";") { // key/value pairs are separated by ';'
			kv := strings.Split(keyAndValue, "=") // key/value are separated by '='
			jpm.fileMetadata[kv[0]] = kv[1]
		}
	}

	jpm.preserveLastModifiedTime = plan.DstLocalData.PreserveLastModifiedTime

	jpm.newJobXfer = computeJobXfer(plan.FromTo)

	jpm.priority = plan.Priority

	jpm.createPipeline(jobCtx) // pipeline is created per job part manager

	// *** Schedule this job part's transfers ***
	for t := uint32(0); t < plan.NumTransfers; t++ {
		jppt := plan.Transfer(t)
		ts := jppt.TransferStatus()
		if ts == common.ETransferStatus.Success() {
			jpm.ReportTransferDone() // Don't schedule an already-completed/failed transfer
			continue
		}

		// If the list of transfer to be included is passed
		// then check current transfer exists in the list of included transfer
		// If it doesn't exists, skip the transfer
		if len(includeTransfer) > 0 {
			// Get the source string from the part plan header
			src, _ := plan.TransferSrcDstStrings(t)
			// If source doesn't exists, skip the transfer
			_, ok := includeTransfer[src]
			if !ok {
				jpm.ReportTransferDone() // Don't schedule transfer which is not mentioned to be included
				continue
			}
		}
		// If the list of transfer to be excluded is passed
		// then check the current transfer in the list of excluded transfer
		// If it exists, then skip the transfer
		if len(excludeTransfer) > 0 {
			// Get the source string from the part plan header
			src, _ := plan.TransferSrcDstStrings(t)
			// If the source exists in the list of excluded transfer
			// skip the transfer
			_, ok := excludeTransfer[src]
			if ok {
				jpm.ReportTransferDone() // Don't schedule transfer which is mentioned to be excluded
				continue
			}
		}

		// If the transfer was failed, then while rescheduling the transfer marking it Started.
		if ts == common.ETransferStatus.Failed() {
			jppt.SetTransferStatus(common.ETransferStatus.Started(), true)
		}

		// Each transfer gets its own context (so any chunk can cancel the whole transfer) based off the job's context
		transferCtx, transferCancel := context.WithCancel(jobCtx)
		jptm := &jobPartTransferMgr{
			jobPartMgr:          jpm,
			jobPartPlanTransfer: jppt,
			transferIndex:       t,
			ctx:                 transferCtx,
			cancel:              transferCancel,
			//TODO: insert the factory func interface in jptm.
			// numChunks will be set by the transfer's prologue method
		}
		if jpm.ShouldLog(pipeline.LogInfo) {
			jpm.Log(pipeline.LogInfo, fmt.Sprintf("scheduling JobID=%v, Part#=%d, Transfer#=%d, priority=%v", plan.JobID, plan.PartNum, t, plan.Priority))
		}

		JobsAdmin.(*jobsAdmin).ScheduleTransfer(jpm.priority, jptm)

		// This sets the atomic variable atomicAllTransfersScheduled to 1
		// atomicAllTransfersScheduled variables is used in case of resume job
		// Since iterating the JobParts and scheduling transfer is independent
		// a variable is required which defines whether last part is resumed or not
		if plan.IsFinalPart {
			jpm.jobMgr.ConfirmAllTransfersScheduled()
		}
	}
}

func (jpm *jobPartMgr) ScheduleChunks(chunkFunc chunkFunc) {
	JobsAdmin.ScheduleChunk(jpm.priority, chunkFunc)
}

func (jpm *jobPartMgr) RescheduleTransfer(jptm IJobPartTransferMgr) {
	JobsAdmin.(*jobsAdmin).ScheduleTransfer(jpm.priority, jptm)
}

// refreshToken is a delegate function for token refreshing.
func (jpm *jobPartMgr) refreshBlobToken(ctx context.Context, tokenInfo common.OAuthTokenInfo, tokenCredential azblob.TokenCredential) time.Duration {
	oauthConfig, err := adal.NewOAuthConfig(tokenInfo.ActiveDirectoryEndpoint, tokenInfo.Tenant)
	if err != nil {
		if jpm.ShouldLog(pipeline.LogError) {
			jpm.Log(pipeline.LogError, fmt.Sprintf("failed to refresh token, due to error: %v", err.Error()))
		}
	}

	spt, err := adal.NewServicePrincipalTokenFromManualToken(*oauthConfig, common.ApplicationID, common.Resource, tokenInfo.Token)
	if err != nil {
		if jpm.ShouldLog(pipeline.LogError) {
			jpm.Log(pipeline.LogError, fmt.Sprintf("failed to refresh token, due to error: %v", err.Error()))
		}
	}

	err = spt.RefreshWithContext(ctx)
	if err != nil {
		if jpm.ShouldLog(pipeline.LogError) {
			jpm.Log(pipeline.LogError, fmt.Sprintf("failed to refresh token, due to error: %v", err.Error()))
		}
	}

	newToken := spt.Token()
	tokenCredential.SetToken(newToken.AccessToken)

	if jpm.ShouldLog(pipeline.LogDebug) {
		jpm.Log(pipeline.LogDebug, fmt.Sprintf("JobID=%v, Part#=%d, token refreshed.", jpm.Plan().JobID, jpm.Plan().PartNum))
	}

	waitDuration := newToken.Expires().Sub(time.Now().UTC()) - common.DefaultTokenExpiryWithinThreshold
	if waitDuration < time.Second {
		waitDuration = time.Nanosecond
	}
	if common.GlobalTestOAuthInjection.DoTokenRefreshInjection {
		waitDuration = common.GlobalTestOAuthInjection.TokenRefreshDuration
	}

	return waitDuration
}

// createCredential creates Azure storage client Credential based on CredentialInfo saved in InMemoryTransitJobState.
func (jpm *jobPartMgr) createBlobCredential(ctx context.Context) azblob.Credential {
	credential := azblob.NewAnonymousCredential()
	inMemoryJobState := jpm.jobMgr.getInMemoryTransitJobState()
	inMemoryTokenInfo := inMemoryJobState.credentialInfo.OAuthTokenInfo

	jpm.Log(pipeline.LogInfo, fmt.Sprintf("JobID=%v, credential type: %v", jpm.Plan().JobID, inMemoryJobState.credentialInfo.CredentialType))

	if inMemoryJobState.credentialInfo.CredentialType == common.ECredentialType.OAuthToken() {
		if inMemoryTokenInfo.IsEmpty() {
			jpm.Panic(fmt.Errorf("invalid state, cannot get valid token info for OAuthToken credential"))
		}

		// Create TokenCredential with refresher.
		return azblob.NewTokenCredential(
			inMemoryTokenInfo.AccessToken,
			func(credential azblob.TokenCredential) time.Duration {
				return jpm.refreshBlobToken(ctx, inMemoryTokenInfo, credential)
			})
	}

	return credential
}

// refreshToken is a delegate function for token refreshing.
func (jpm *jobPartMgr) refreshBlobFSToken(ctx context.Context, tokenInfo common.OAuthTokenInfo, tokenCredential azbfs.TokenCredential) time.Duration {
	oauthConfig, err := adal.NewOAuthConfig(tokenInfo.ActiveDirectoryEndpoint, tokenInfo.Tenant)
	if err != nil {
		if jpm.ShouldLog(pipeline.LogError) {
			jpm.Log(pipeline.LogError, fmt.Sprintf("failed to refresh token, due to error: %v", err.Error()))
		}
	}

	spt, err := adal.NewServicePrincipalTokenFromManualToken(*oauthConfig, common.ApplicationID, common.Resource, tokenInfo.Token)
	if err != nil {
		if jpm.ShouldLog(pipeline.LogError) {
			jpm.Log(pipeline.LogError, fmt.Sprintf("failed to refresh token, due to error: %v", err.Error()))
		}
	}

	err = spt.RefreshWithContext(ctx)
	if err != nil {
		if jpm.ShouldLog(pipeline.LogError) {
			jpm.Log(pipeline.LogError, fmt.Sprintf("failed to refresh token, due to error: %v", err.Error()))
		}
	}

	newToken := spt.Token()
	tokenCredential.SetToken(newToken.AccessToken)

	if jpm.ShouldLog(pipeline.LogDebug) {
		jpm.Log(pipeline.LogDebug, fmt.Sprintf("JobID=%v, Part#=%d, token refreshed.", jpm.Plan().JobID, jpm.Plan().PartNum))
	}

	waitDuration := newToken.Expires().Sub(time.Now().UTC()) - common.DefaultTokenExpiryWithinThreshold
	if waitDuration < time.Second {
		waitDuration = time.Nanosecond
	}
	if common.GlobalTestOAuthInjection.DoTokenRefreshInjection {
		waitDuration = common.GlobalTestOAuthInjection.TokenRefreshDuration
	}

	return waitDuration
}

// createCredential creates Azure storage client Credential based on CredentialInfo saved in InMemoryTransitJobState.
func (jpm *jobPartMgr) createBlobFSCredential(ctx context.Context) azbfs.Credential {
	inMemoryJobState := jpm.jobMgr.getInMemoryTransitJobState()
	inMemoryCredType := inMemoryJobState.credentialInfo.CredentialType
	inMemoryTokenInfo := inMemoryJobState.credentialInfo.OAuthTokenInfo

	jpm.Log(pipeline.LogInfo, fmt.Sprintf("JobID=%v, credential type: %v", jpm.Plan().JobID, inMemoryJobState.credentialInfo.CredentialType))

	switch inMemoryCredType {
	case common.ECredentialType.SharedKey(): // For testing
		// Get the Account Name and Key variables from environment
		name := os.Getenv("ACCOUNT_NAME")
		key := os.Getenv("ACCOUNT_KEY")
		// If the ACCOUNT_NAME and ACCOUNT_KEY are not set in environment variables
		if name == "" || key == "" {
			jpm.Panic(errors.New("ACCOUNT_NAME and ACCOUNT_KEY environment vars must be set before creating the blobfs pipeline"))
		}
		return azbfs.NewSharedKeyCredential(name, key)
	case common.ECredentialType.OAuthToken():
		if inMemoryTokenInfo.IsEmpty() {
			jpm.Panic(errors.New("invalid state, cannot get valid token info for OAuthToken credential"))
		}

		// Create TokenCredential with refresher.
		return azbfs.NewTokenCredential(
			inMemoryTokenInfo.AccessToken,
			func(credential azbfs.TokenCredential) time.Duration {
				return jpm.refreshBlobFSToken(ctx, inMemoryTokenInfo, credential)
			})
	default:
		jpm.Panic(fmt.Errorf("invalid state, credential type %v is not supported", inMemoryCredType))

		// Suppress compiler warning
		return nil
	}
}

func (jpm *jobPartMgr) createPipeline(ctx context.Context) {
	if jpm.pipeline == nil {
		fromTo := jpm.planMMF.Plan().FromTo

		switch fromTo {
		// Create pipeline for Azure Blob.
		case common.EFromTo.BlobTrash(), common.EFromTo.BlobLocal(), common.EFromTo.LocalBlob(),
			common.EFromTo.BlobBlob(), common.EFromTo.FileBlob():
			credential := jpm.createBlobCredential(ctx)
			jpm.pipeline = NewBlobPipeline(
				credential,
				azblob.PipelineOptions{
					Log: jpm.jobMgr.PipelineLogInfo(),
					Telemetry: azblob.TelemetryOptions{
						Value: common.UserAgent,
					},
				},
				XferRetryOptions{
					Policy:        0,
					MaxTries:      UploadMaxTries,
					TryTimeout:    UploadTryTimeout,
					RetryDelay:    UploadRetryDelay,
					MaxRetryDelay: UploadMaxRetryDelay},
				jpm.pacer)
		// Create pipeline for Azure BlobFS.
		case common.EFromTo.BlobFSLocal(), common.EFromTo.LocalBlobFS():
			credential := jpm.createBlobFSCredential(ctx)
			jpm.pipeline = NewBlobFSPipeline(
				credential,
				azbfs.PipelineOptions{
					Log: jpm.jobMgr.PipelineLogInfo(),
					Telemetry: azbfs.TelemetryOptions{
						Value: common.UserAgent,
					},
				},
				XferRetryOptions{
					Policy:        0,
					MaxTries:      UploadMaxTries,
					TryTimeout:    UploadTryTimeout,
					RetryDelay:    UploadRetryDelay,
					MaxRetryDelay: UploadMaxRetryDelay},
				jpm.pacer)
		// Create pipeline for Azure File.
		case common.EFromTo.FileTrash(), common.EFromTo.FileLocal(), common.EFromTo.LocalFile():
			jpm.pipeline = newFilePipeline(
				azfile.NewAnonymousCredential(),
				azfile.PipelineOptions{
					Log: jpm.jobMgr.PipelineLogInfo(),
					Telemetry: azfile.TelemetryOptions{
						Value: common.UserAgent,
					},
				},
				azfile.RetryOptions{
					Policy:        azfile.RetryPolicyExponential,
					MaxTries:      UploadMaxTries,
					TryTimeout:    UploadTryTimeout,
					RetryDelay:    UploadRetryDelay,
					MaxRetryDelay: UploadMaxRetryDelay,
				},
				jpm.pacer)
		default:
			panic(fmt.Errorf("Unrecognized FromTo: %q", fromTo.String()))
		}
	}
}

func (jpm *jobPartMgr) StartJobXfer(jptm IJobPartTransferMgr) {
	//jpm.createPipeline() //TODO: Ensure with @Jeff and @Prateek, as pipeline is created per jobPartMgr, it is moved to ScheduleTransfers
	jpm.newJobXfer(jptm, jpm.pipeline, jpm.pacer)
}

func (jpm *jobPartMgr) IsForceWriteTrue() bool {
	return jpm.Plan().ForceWrite
}

func (jpm *jobPartMgr) blobDstData(dataFileToXfer *common.MMF) (headers azblob.BlobHTTPHeaders, metadata azblob.Metadata) {
	if jpm.planMMF.Plan().DstBlobData.NoGuessMimeType || dataFileToXfer == nil {
		return jpm.blobHTTPHeaders, jpm.blobMetadata
	}
	return azblob.BlobHTTPHeaders{ContentType: http.DetectContentType(dataFileToXfer.Slice())}, jpm.blobMetadata
}

func (jpm *jobPartMgr) fileDstData(dataFileToXfer *common.MMF) (headers azfile.FileHTTPHeaders, metadata azfile.Metadata) {
	if jpm.planMMF.Plan().DstBlobData.NoGuessMimeType || dataFileToXfer == nil {
		return jpm.fileHTTPHeaders, jpm.fileMetadata
	}
	return azfile.FileHTTPHeaders{ContentType: http.DetectContentType(dataFileToXfer.Slice())}, jpm.fileMetadata
}

func (jpm *jobPartMgr) BlobTiers() (blockBlobTier common.BlockBlobTier, pageBlobTier common.PageBlobTier) {
	return jpm.blockBlobTier, jpm.pageBlobTier
}

func (jpm *jobPartMgr) SAS() (string, string) {
	return jpm.sourceSAS, jpm.destinationSAS
}

func (jpm *jobPartMgr) localDstData() (preserveLastModifiedTime bool) {
	dstData := &jpm.Plan().DstLocalData
	return dstData.PreserveLastModifiedTime
}

// Call Done when a transfer has completed its epilog; this method returns the number of transfers completed so far
func (jpm *jobPartMgr) ReportTransferDone() (transfersDone uint32) {
	transfersDone = atomic.AddUint32(&jpm.atomicTransfersDone, 1)
	if jpm.ShouldLog(pipeline.LogInfo) {
		plan := jpm.Plan()
		jpm.Log(pipeline.LogInfo, fmt.Sprintf("JobID=%v, Part#=%d, TransfersDone=%d of %d", plan.JobID, plan.PartNum, transfersDone, plan.NumTransfers))
	}
	if transfersDone == jpm.planMMF.Plan().NumTransfers {
		jpm.jobMgr.ReportJobPartDone()
	}
	return transfersDone
}

//func (jpm *jobPartMgr) Cancel() { jpm.jobMgr.Cancel() }
func (jpm *jobPartMgr) Close() {
	jpm.planMMF.Unmap()
	// Clear other fields to all for GC
	jpm.blobHTTPHeaders = azblob.BlobHTTPHeaders{}
	jpm.blobMetadata = azblob.Metadata{}
	jpm.fileHTTPHeaders = azfile.FileHTTPHeaders{}
	jpm.fileMetadata = azfile.Metadata{}
	jpm.preserveLastModifiedTime = false
	// TODO: Delete file?
	/*if err := os.Remove(jpm.planFile.Name()); err != nil {
		jpm.Panic(fmt.Errorf("error removing Job Part Plan file %s. Error=%v", jpm.planFile.Name(), err))
	}*/
}

// TODO: added for debugging purpose. remove later
// Add 1 to the active number of goroutine performing the transfer or executing the chunkFunc
func (jpm *jobPartMgr) OccupyAConnection() {
	jpm.jobMgr.OccupyAConnection()
}

// Sub 1 from the active number of goroutine performing the transfer or executing the chunkFunc
// TODO: added for debugging purpose. remove later
func (jpm *jobPartMgr) ReleaseAConnection() {
	jpm.jobMgr.ReleaseAConnection()
}

func (jpm *jobPartMgr) ShouldLog(level pipeline.LogLevel) bool  { return jpm.jobMgr.ShouldLog(level) }
func (jpm *jobPartMgr) Log(level pipeline.LogLevel, msg string) { jpm.jobMgr.Log(level, msg) }
func (jpm *jobPartMgr) Panic(err error)                         { jpm.jobMgr.Panic(err) }

// TODO: Can we delete this method?
// numberOfTransfersDone returns the numberOfTransfersDone_doNotUse of JobPartPlanInfo
// instance in thread safe manner
//func (jpm *jobPartMgr) numberOfTransfersDone() uint32 {	return atomic.LoadUint32(&jpm.numberOfTransfersDone_doNotUse)}

// setNumberOfTransfersDone sets the number of transfers done to a specific value
// in a thread safe manner
//func (jppi *jobPartPlanInfo) setNumberOfTransfersDone(val uint32) {
//	atomic.StoreUint32(&jPartPlanInfo.numberOfTransfersDone_doNotUse, val)
//}