fix(index): add build id ordering to channel head selection

Add a semver version preference to [build IDs](https://semver.org/#spec-item-10) to accommodate existing published content making use of them to differentiate between successive releases of the same version.

Rule: when two versions are semver equivalent, compare their build IDs as if they were [prereleases](https://semver.org/#spec-item-9).

e.g. `1.2.3+1.2.3` and `1.2.3+1.1.55` are evaluated to `1.0.0-1.2.3` and `1.0.0-1.1.55` respectively and compared. This yields  `1.0.0-1.2.3 < 1.0.0-1.1.55` which is then mapped back to `1.2.3+1.2.3 < 1.2.3+1.1.55`

Additionally, split bundle addition and upgrade graph generation into two
distinct steps. This reduces the number of times opm needs to generate
the graph on index add, from once-per-bundle added to a package, to
once-per-add operation (for a package). This also prevents opm from
choking on existing, intermediate, bundles using semver incorrectly;
e.g. `1.0.0-1` replaces `1.0.0-2` when `2.0.0` is being overwritten.

Signed-off-by: Nick Hale <[email protected]>

Author: njhale

pkg/registry/graph.go

@@ -2,6 +2,7 @@ package registry
 
 import (
 	"fmt"
+	"strings"
 )
 
 type Package struct {
@@ -10,11 +11,38 @@ type Package struct {
 	Channels       map[string]Channel
 }
 
+func (p *Package) String() string {
+	var b strings.Builder
+	b.WriteString("name: ")
+	b.WriteString(p.Name)
+	b.WriteString("\ndefault channel: ")
+	b.WriteString(p.DefaultChannel)
+	b.WriteString("\nchannels:\n")
+
+	for n, c := range p.Channels {
+		b.WriteString(n)
+		b.WriteString("\n")
+		b.WriteString(c.String())
+	}
+
+	return b.String()
+}
+
 type Channel struct {
 	Head  BundleKey
 	Nodes map[BundleKey]map[BundleKey]struct{}
 }
 
+func (c *Channel) String() string {
+	var b strings.Builder
+	for node, _ := range c.Nodes {
+		b.WriteString(node.String())
+		b.WriteString("\n")
+	}
+
+	return b.String()
+}
+
 type BundleKey struct {
 	BundlePath string
 	Version    string //semver string

pkg/registry/helper_test.go

@@ -0,0 +1,222 @@
+package registry
+
+import (
+	"testing"
+
+	"github.com/blang/semver"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBundleVersionCompare(t *testing.T) {
+	type fields struct {
+		version string
+	}
+	type args struct {
+		version string
+	}
+
+	type order func(t *testing.T, val int)
+	var (
+		lt order = func(t *testing.T, val int) {
+			require.Less(t, val, 0)
+		}
+		gt order = func(t *testing.T, val int) {
+			require.Greater(t, val, 0)
+		}
+		eq order = func(t *testing.T, val int) {
+			require.Equal(t, val, 0)
+		}
+	)
+	type expect struct {
+		order order
+	}
+
+	for _, tt := range []struct {
+		description string
+		fields      fields
+		args        args
+		expect      expect
+	}{
+		{
+			description: "BuildMetaAscendingLT",
+			fields: fields{
+				version: "1.0.0+1",
+			},
+			args: args{
+				version: "1.0.0+2",
+			},
+			expect: expect{
+				order: lt,
+			},
+		},
+		{
+			description: "BuildMetaDescendingGT",
+			fields: fields{
+				version: "1.0.0+2",
+			},
+			args: args{
+				version: "1.0.0+1",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+		{
+			description: "BuildMetaGT",
+			fields: fields{
+				version: "1.0.0+1",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+		{
+			description: "BuildMetaEQ",
+			fields: fields{
+				version: "1.0.0+1",
+			},
+			args: args{
+				version: "1.0.0+1",
+			},
+			expect: expect{
+				order: eq,
+			},
+		},
+		{
+			description: "BuildMetaZeroGT",
+			fields: fields{
+				version: "1.0.0+0",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+		{
+			description: "BuildMetaMultipartLT",
+			fields: fields{
+				version: "1.0.0+0",
+			},
+			args: args{
+				version: "1.0.0+1.2.3",
+			},
+			expect: expect{
+				order: lt,
+			},
+		},
+		{
+			description: "PatchAscendingLT",
+			fields: fields{
+				version: "1.0.0",
+			},
+			args: args{
+				version: "1.0.1",
+			},
+			expect: expect{
+				order: lt,
+			},
+		},
+		{
+			description: "PatchDescendingGT",
+			fields: fields{
+				version: "1.0.1",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+		{
+			description: "MinorAscendingLT",
+			fields: fields{
+				version: "1.0.0",
+			},
+			args: args{
+				version: "1.1.0",
+			},
+			expect: expect{
+				order: lt,
+			},
+		},
+		{
+			description: "MinorDescendingGT",
+			fields: fields{
+				version: "1.1.0",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+		{
+			description: "MajorAscendingLT",
+			fields: fields{
+				version: "1.0.0",
+			},
+			args: args{
+				version: "2.0.0",
+			},
+			expect: expect{
+				order: lt,
+			},
+		},
+		{
+			description: "MajorDescendingGT",
+			fields: fields{
+				version: "2.0.0",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+		{
+			description: "PrereleaseLT",
+			fields: fields{
+				version: "1.0.0-pre",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: lt,
+			},
+		},
+		{
+			description: "PrereleaseGT",
+			fields: fields{
+				version: "2.0.0-pre",
+			},
+			args: args{
+				version: "1.0.0",
+			},
+			expect: expect{
+				order: gt,
+			},
+		},
+	} {
+		t.Run(tt.description, func(t *testing.T) {
+			fieldVersion, err := semver.Parse(tt.fields.version)
+			require.NoErrorf(t, err, "bad testcase")
+
+			argVersion, err := semver.Parse(tt.args.version)
+			require.NoErrorf(t, err, "bad testcase")
+
+			c, err := bundleVersion{version: fieldVersion}.compare(bundleVersion{version: argVersion})
+			require.NoError(t, err)
+
+			tt.expect.order(t, c)
+		})
+	}
+}