Fix OVA generation

- Flush after last header - rename the VM to MigrationAssessment - Send Content-Type and Content-length headers Signed-off-by: Ondra Machacek <[email protected]>
kubev2v · Dec 16, 2024 · be8b922 · be8b922
1 parent b3dcc8f
commit be8b922
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Showing 4 changed files with 82 additions and 8 deletions.
diff --git a/data/AgentVM.ovf → data/MigrationAssessment.ovf b/data/AgentVM.ovf → data/MigrationAssessment.ovf
@@ -1,15 +1,15 @@
 <?xml version='1.0' encoding='UTF-8'?>
 <Envelope xmlns="http://schemas.dmtf.org/ovf/envelope/1" xmlns:ovf="http://schemas.dmtf.org/ovf/envelope/1" xmlns:vmw="http://www.vmware.com/schema/ovf" xmlns:rasd="http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData" xmlns:vssd="http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_VirtualSystemSettingData">
   <References>
-    <File ovf:id="file1" ovf:href="AgentVM-1.iso" ovf:size="1220542464"/>
+    <File ovf:id="file1" ovf:href="MigrationAssessment.iso" ovf:size="1220542464"/>
   </References>
   <NetworkSection>
     <Info>The list of logical networks</Info>
     <Network ovf:name="routable-network">
       <Description>Routable network</Description>
     </Network>
   </NetworkSection>
-  <VirtualSystem ovf:id="AgentVM">
+  <VirtualSystem ovf:id="MigrationAssessment">
     <Info>A Virtual system</Info>
     <Name>MigrationAssessment</Name>
     <OperatingSystemSection ovf:id="80" ovf:version="8" vmw:osType="rhel9_64Guest">

diff --git a/internal/image/ova.go b/internal/image/ova.go
@@ -51,6 +51,31 @@ func (o *Ova) Validate() error {
 	return nil
 }
 
+func calculateTarSize(contentSize int) int {
+	const blockSize = 512
+
+	// Size of the tar header block
+	size := blockSize
+
+	// Size of the file content, rounded up to nearest 512 bytes
+	size += ((contentSize + blockSize - 1) / blockSize) * blockSize
+
+	return size
+}
+
+func (o *Ova) OvaSize() (int, error) {
+	isoSize, err := o.isoSize()
+	if err != nil {
+		return -1, err
+	}
+	ovfSize, err := o.ovfSize()
+	if err != nil {
+		return -1, err
+	}
+
+	return ovfSize + isoSize, nil
+}
+
 func (o *Ova) Generate() error {
 	tw := tar.NewWriter(o.Writer)
 
@@ -64,6 +89,8 @@ func (o *Ova) Generate() error {
 		return err
 	}
 
+	tw.Flush()
+
 	return nil
 }
 
@@ -88,13 +115,13 @@ func (o *Ova) writeIso(tw *tar.Writer) error {
 	if err != nil {
 		return err
 	}
-	// Create a header for AgentVM-1.iso
+	// Create a header for MigrationAssessment.iso
 	length, err := reader.Seek(0, io.SeekEnd)
 	if err != nil {
 		return err
 	}
 	header := &tar.Header{
-		Name:    "AgentVM-1.iso",
+		Name:    "MigrationAssessment.iso",
 		Size:    length,
 		Mode:    0600,
 		ModTime: time.Now(),
@@ -118,14 +145,48 @@ func (o *Ova) writeIso(tw *tar.Writer) error {
 	return nil
 }
 
+func (o *Ova) isoSize() (int, error) {
+	// Get ISO reader
+	reader, err := o.isoReader()
+	if err != nil {
+		return -1, err
+	}
+	length, err := reader.Seek(0, io.SeekEnd)
+	if err != nil {
+		return -1, err
+	}
+
+	// Reset the reader to start
+	_, err = reader.Seek(0, io.SeekStart)
+	if err != nil {
+		return -1, err
+	}
+
+	return calculateTarSize(int(length)), nil
+}
+
+func (o *Ova) ovfSize() (int, error) {
+	file, err := os.Open("data/MigrationAssessment.ovf")
+	if err != nil {
+		return -1, err
+	}
+	defer file.Close()
+	fileInfo, err := file.Stat()
+	if err != nil {
+		return -1, err
+	}
+
+	return calculateTarSize(int(fileInfo.Size())), nil
+}
+
 func writeOvf(tw *tar.Writer) error {
-	ovfContent, err := os.ReadFile("data/AgentVM.ovf")
+	ovfContent, err := os.ReadFile("data/MigrationAssessment.ovf")
 	if err != nil {
 		return err
 	}
 	// Create a header for AgentVM.ovf
 	header := &tar.Header{
-		Name:    "AgentVM.ovf",
+		Name:    "MigrationAssessment.ovf",
 		Size:    int64(len(ovfContent)),
 		Mode:    0600,
 		ModTime: time.Now(),

diff --git a/internal/service/image.go b/internal/service/image.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"strconv"
 
 	"github.com/kubev2v/migration-planner/internal/api/server"
 	"github.com/kubev2v/migration-planner/internal/auth"
@@ -16,12 +17,24 @@ func (h *ServiceHandler) GetImage(ctx context.Context, request server.GetImageRe
 	if !ok {
 		return server.GetImage500JSONResponse{Message: "error creating the HTTP stream"}, nil
 	}
-
 	ova := &image.Ova{SshKey: request.Params.SshKey, Writer: writer}
+
 	// get token if any
 	if user, found := auth.UserFromContext(ctx); found {
 		ova.Jwt = user.Token
 	}
+
+	// Calculate the size of the OVA, so the download show estimated time:
+	size, err := ova.OvaSize()
+	if err != nil {
+		return server.GetImage500JSONResponse{Message: "error creating the HTTP stream"}, nil
+	}
+
+	// Set proper headers of the OVA file:
+	writer.Header().Set("Content-Type", "application/ovf")
+	writer.Header().Set("Content-Length", strconv.Itoa(size))
+
+	// Generate the OVA image
 	if err := ova.Generate(); err != nil {
 		return server.GetImage500JSONResponse{Message: fmt.Sprintf("error generating image %s", err)}, nil
 	}

diff --git a/test/e2e/e2e_agent_test.go b/test/e2e/e2e_agent_test.go
@@ -104,7 +104,7 @@ func (p *plannerAgentLibvirt) prepareImage() error {
 	}
 
 	// Untar ISO from OVA
-	if err = Untar(file, defaultIsoPath, "AgentVM-1.iso"); err != nil {
+	if err = Untar(file, defaultIsoPath, "MigrationAssessment.iso"); err != nil {
 		return fmt.Errorf("error uncompressing the file: %w", err)
 	}