✨ Support extenion compat with addon as regex. (konveyor#782)

Both the analyzer and tech-discovery both use the same providers. An
extension having compatibility with multiple addons is not a
common/mainstream use case. To get around this, we have defined a
duplicate set of extensions for each provider. One with compatibility
with the `analyzer` addon and the other for the `tech-discovery` addon.

After a recent refactor of the generic extension into multiple
extensions (go, python, nodejs), it became obvious that maintain the
duplicate set of extensions is painful and likely error prone.

It seems a better approach is to change `Extention.Spec.Addon` to
(optionally) define a regex. This approach caters to the mainstream use
case that extensions have compatibility with one addon. It also avoids
making the field an _array_ requiring a CRD change. This is which is
MUCH simpler.

The existing extensions will need to be updated to be compatible with
both addons.
Example (java extension):
```
addon: ^(analyzer|tech-discovery)$
```

The `discovery-` extensions would be deleted.

---------

Signed-off-by: Jeff Ortel <[email protected]>

settings/hub.go

@@ -368,6 +368,7 @@ func (r *Hub) namespace() (ns string, err error) {
 // build returns the hub build version.
 // This is expected to be the output of `git describe`.
 // Examples:
+//
 //	v0.6.0-ea89gcd
 //	v0.6.0
 func (r *Hub) build() (version string, err error) {

task/error.go

@@ -231,6 +231,25 @@ func (e *SelectorNotValid) Retry() (r bool) {
 	return
 }
 
+// ExtAddonNotValid reports extension addon ref error.
+type ExtAddonNotValid struct {
+	Extension string
+	Reason    string
+}
+
+func (e *ExtAddonNotValid) Error() string {
+	return fmt.Sprintf(
+		"Extension '%s' addon ref not valid. reason: %s",
+		e.Extension,
+		e.Reason)
+}
+
+func (e *ExtAddonNotValid) Is(err error) (matched bool) {
+	var inst *ExtAddonNotValid
+	matched = errors.As(err, &inst)
+	return
+}
+
 // PriorityNotFound report priority class not found.
 type PriorityNotFound struct {
 	Name  string

task/manager.go

@@ -8,6 +8,7 @@ import (
 	"io"
 	"os"
 	"path"
+	"regexp"
 	"sort"
 	"strconv"
 	"strings"
@@ -88,6 +89,10 @@ const (
 	Cache  = "cache"
 )
 
+var (
+	IsRegex = regexp.MustCompile("[^0-9A-Za-z_-]")
+)
+
 var (
 	Settings = &settings.Settings
 	Log      = logr.WithName("task-scheduler")
@@ -555,7 +560,11 @@ func (m *Manager) selectExtensions(task *Task, addon *crd.Addon) (err error) {
 	matched := false
 	selector := NewSelector(m.DB, task)
 	for _, extension := range m.cluster.Extensions() {
-		if extension.Spec.Addon != addon.Name {
+		matched, err = m.matchAddon(extension, addon)
+		if err != nil {
+			return
+		}
+		if !matched {
 			continue
 		}
 		matched, err = selector.Match(extension.Spec.Selector)
@@ -570,6 +579,30 @@ func (m *Manager) selectExtensions(task *Task, addon *crd.Addon) (err error) {
 	return
 }
 
+// matchAddon - returns true when the extension's `addon`
+// (ref) matches the addon name.
+// The `ref` is matched as a REGEX when it contains
+// characters other than: [0-9A-Za-z_].
+func (m *Manager) matchAddon(extension *crd.Extension, addon *crd.Addon) (matched bool, err error) {
+	ref := strings.TrimSpace(extension.Spec.Addon)
+	p := IsRegex
+	if p.MatchString(ref) {
+		p, err = regexp.Compile(ref)
+		if err != nil {
+			err = &ExtAddonNotValid{
+				Extension: extension.Name,
+				Reason:    err.Error(),
+			}
+			return
+		}
+		matched = p.MatchString(addon.Name)
+	} else {
+
+		matched = addon.Name == ref
+	}
+	return
+}
+
 // postpone Postpones a task as needed based on rules.
 // postpone order:
 // - priority (lower)

task/task_test.go

@@ -135,3 +135,34 @@ func TestPriorityGraph(t *testing.T) {
 	deps := pE.graph(ready[0], ready)
 	g.Expect(len(deps)).To(gomega.Equal(2))
 }
+
+func TestAddonRegex(t *testing.T) {
+	g := gomega.NewGomegaWithT(t)
+	m := Manager{}
+	addonA := &crd.Addon{}
+	addonA.Name = "A"
+	addonB := &crd.Addon{}
+	addonB.Name = "B"
+	// direct.
+	ext := &crd.Extension{}
+	ext.Name = "Test"
+	ext.Spec.Addon = "A"
+	matched, err := m.matchAddon(ext, addonA)
+	g.Expect(err).To(gomega.BeNil())
+	g.Expect(matched).To(gomega.BeTrue())
+	matched, err = m.matchAddon(ext, addonB)
+	g.Expect(err).To(gomega.BeNil())
+	g.Expect(matched).To(gomega.BeFalse())
+	// regex.
+	ext.Spec.Addon = "^(A|B)$"
+	matched, err = m.matchAddon(ext, addonA)
+	g.Expect(err).To(gomega.BeNil())
+	g.Expect(matched).To(gomega.BeTrue())
+	matched, err = m.matchAddon(ext, addonB)
+	g.Expect(err).To(gomega.BeNil())
+	g.Expect(matched).To(gomega.BeTrue())
+	// regex not valid.
+	ext.Spec.Addon = "(]$"
+	matched, err = m.matchAddon(ext, addonA)
+	g.Expect(err).ToNot(gomega.BeNil())
+}