MGMT-16242: Suggest OCP images based on availability for architecture

This feature will suggest Openshift versions that are available for the release images of an architecture in the case that no release images for the supplied version are found.
This is to aid the user in picking a different version.

internal/versions/common.go

@@ -4,6 +4,7 @@ import (
 	context "context"
 	"encoding/json"
 	"fmt"
+	"strings"
 	"sync"
 
 	"github.com/go-openapi/strfmt"
@@ -128,19 +129,18 @@ func validateReleaseImageForRHCOS(
 ) error {
 	// Multi is not a valid RHCOS CPU architecture, its sub-architectures are
 	if cpuArchitecture == common.MultiCPUArchitecture {
-		return errors.Errorf("The requested RHCOS version (%s, arch: %s) does not have a matching OpenShift release image", rhcosVersion, cpuArchitecture)
+		return errors.Errorf("The requested RHCOS version (%s, arch: %s) does not have a matching OpenShift release image, there are no valid Openshift versions for architecture %s", rhcosVersion, cpuArchitecture, common.MultiCPUArchitecture)
 	}
-
 	rhcosVersionPtr, err := common.GetMajorMinorVersion(rhcosVersion)
 	if err != nil {
 		return err
 	}
-
 	if cpuArchitecture == "" {
 		// Empty implies default CPU architecture
 		cpuArchitecture = common.DefaultCPUArchitecture
 	}
 
+	availableOCPVersions := []string{}
 	for _, releaseImage := range releaseImages {
 		minorVersion, err := common.GetMajorMinorVersion(*releaseImage.OpenshiftVersion)
 		if err != nil {
@@ -160,9 +160,15 @@ func validateReleaseImageForRHCOS(
 				}
 			}
 		}
+		if swag.ContainsStrings(releaseImage.CPUArchitectures, cpuArchitecture) && !swag.ContainsStrings(availableOCPVersions, swag.StringValue(minorVersion)) {
+			availableOCPVersions = append(availableOCPVersions, swag.StringValue(releaseImage.OpenshiftVersion))
+		}
 	}
-
-	return errors.Errorf("The requested RHCOS version (%s, arch: %s) does not have a matching OpenShift release image", *rhcosVersionPtr, cpuArchitecture)
+	ocpVersionAdvice := fmt.Sprintf("There are no OCP versions available in release images for arch %s.", cpuArchitecture)
+	if len(availableOCPVersions) > 0 {
+		ocpVersionAdvice = fmt.Sprintf("The following OCP versions are available in release images for arch %s: %s", cpuArchitecture, strings.Join(availableOCPVersions, ","))
+	}
+	return errors.Errorf("The requested RHCOS version (%s, arch: %s) does not have a matching OpenShift release image. %s", *rhcosVersionPtr, cpuArchitecture, ocpVersionAdvice)
 }
 
 func AddReleaseImagesToDBIfNeeded(

internal/versions/common_test.go

@@ -3,6 +3,7 @@ package versions
 import (
 	context "context"
 	"fmt"
+	"strings"
 	"sync"
 
 	"github.com/go-openapi/swag"
@@ -177,6 +178,26 @@ var _ = Describe("validateReleaseImageForRHCOS", func() {
 	It("fails validation using invalid version", func() {
 		Expect(validateReleaseImageForRHCOS(log, "invalid", common.X86CPUArchitecture, releaseImages)).NotTo(Succeed())
 	})
+
+	It("advises on suitable Openshift versions if unable to find release image for architecture", func() {
+		err := validateReleaseImageForRHCOS(log, "9.9.9-chocobomb", common.X86CPUArchitecture, releaseImages)
+		Expect(err).ToNot(BeNil())
+		errorMessage := err.Error()
+		Expect(errorMessage).To(ContainSubstring(fmt.Sprintf("The requested RHCOS version (%s, arch: %s) does not have a matching OpenShift release image.", "9.9", common.X86CPUArchitecture)))
+		Expect(errorMessage).To(ContainSubstring(fmt.Sprintf("The following OCP versions are available in release images for arch %s:", common.X86CPUArchitecture)))
+		splitErrorMessage := strings.Split(errorMessage, ":")
+		Expect(len(splitErrorMessage)).To(Equal(3))
+		versionsSplit := strings.Split(strings.Trim(splitErrorMessage[2], " "), ",")
+		Expect(versionsSplit).To(ContainElement("4.11.1"))
+		Expect(versionsSplit).To(ContainElement("4.12"))
+
+	})
+
+	It("advises that no Openshift versions are available in release images if none found for architecture", func() {
+		err := validateReleaseImageForRHCOS(log, "9.9.9-chocobomb", common.PowerCPUArchitecture, releaseImages)
+		Expect(err).ToNot(BeNil())
+		Expect(err.Error()).To(ContainSubstring(fmt.Sprintf("There are no OCP versions available in release images for arch %s.", common.PowerCPUArchitecture)))
+	})
 })
 
 var _ = Describe("GetMustGatherImages", func() {