feat: types/functions for images and Postgres versions (#29)

Signed-off-by: Leonardo Cecchi <leonardo.cecchi@enterprisedb.com>
Signed-off-by: Francesco Canovai <francesco.canovai@enterprisedb.com>
Signed-off-by: Gabriele Bartolini <gabriele.bartolini@enterprisedb.com>
Co-authored-by: Gabriele Bartolini <gabriele.bartolini@enterprisedb.com>

pkg/image/reference/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package reference contains an image reference
+// parser
+package reference

pkg/image/reference/imagename.go

@@ -0,0 +1,78 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package reference
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+)
+
+var (
+	digestRegex = regexp.MustCompile(`@sha256:(?P<sha256>[a-fA-F0-9]+)$`)
+	tagRegex    = regexp.MustCompile(`:(?P<tag>[^/]+)$`)
+	hostRegex   = regexp.MustCompile(`^[^./:]+((\.[^./:]+)+(:[0-9]+)?|:[0-9]+)/`)
+)
+
+// Data is the main data type
+type Data struct {
+	Name   string
+	Tag    string
+	Digest string
+}
+
+// GetNormalizedName returns the normalized name of a reference
+func (r *Data) GetNormalizedName() (name string) {
+	name = r.Name
+	if r.Tag != "" {
+		name = fmt.Sprintf("%s:%s", name, r.Tag)
+	}
+	if r.Digest != "" {
+		name = fmt.Sprintf("%s@sha256:%s", name, r.Digest)
+	}
+	return name
+}
+
+// New parses the image name and returns an error if the name is invalid.
+func New(name string) *Data {
+	reference := &Data{}
+
+	if !strings.Contains(name, "/") {
+		name = "docker.io/library/" + name
+	} else if !hostRegex.MatchString(name) {
+		name = "docker.io/" + name
+	}
+
+	if digestRegex.MatchString(name) {
+		res := digestRegex.FindStringSubmatch(name)
+		reference.Digest = res[1] // digest capture group index
+		name = strings.TrimSuffix(name, res[0])
+	}
+
+	if tagRegex.MatchString(name) {
+		res := tagRegex.FindStringSubmatch(name)
+		reference.Tag = res[1] // tag capture group index
+		name = strings.TrimSuffix(name, res[0])
+	} else if reference.Digest == "" {
+		reference.Tag = "latest"
+	}
+
+	// everything else is the name
+	reference.Name = name
+
+	return reference
+}

pkg/image/reference/imagename_test.go

@@ -0,0 +1,49 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package reference
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("image name management", func() {
+	It("should normalize image names", func() {
+		Expect(New("postgres").GetNormalizedName()).To(
+			Equal("docker.io/library/postgres:latest"))
+		Expect(New("myimage/postgres").GetNormalizedName()).To(
+			Equal("docker.io/myimage/postgres:latest"))
+		Expect(New("localhost:5000/postgres").GetNormalizedName()).To(
+			Equal("localhost:5000/postgres:latest"))
+		Expect(New("registry.localhost:5000/postgres:14.4").GetNormalizedName()).To(
+			Equal("registry.localhost:5000/postgres:14.4"))
+		Expect(New("ghcr.io/cloudnative-pg/postgresql:34").GetNormalizedName()).To(
+			Equal("ghcr.io/cloudnative-pg/postgresql:34"))
+	})
+
+	It("should extract tag names", func() {
+		Expect(New("postgres").Tag).To(Equal("latest"))
+		Expect(New("postgres:34.3").Tag).To(Equal("34.3"))
+		Expect(New("postgres:13@sha256:cff94de382ca538861622bbe84cfe03f44f307a9846a5c5eda672cf4dc692866").Tag).
+			To(Equal("13"))
+	})
+
+	It("should not extract a tag name", func() {
+		Expect(New("postgres@sha256:cff94dd382ca538861622bbe84cfe03f44f307a9846a5c5eda672cf4dc692866").Tag).
+			To(BeEmpty())
+	})
+})

pkg/image/reference/suite_test.go

@@ -0,0 +1,33 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package reference
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+// These tests use Ginkgo (BDD-style Go testing framework). Refer to
+// http://onsi.github.io/ginkgo/ to learn more about Ginkgo.
+
+func TestPostgresVersion(t *testing.T) {
+	RegisterFailHandler(Fail)
+
+	RunSpecs(t, "PostgreSQL Version")
+}

pkg/postgres/version/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package version contains a PostgreSQL image version parser with
+// the corresponding data type and operations on it
+package version

pkg/postgres/version/suite_test.go

@@ -0,0 +1,33 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package version
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+// These tests use Ginkgo (BDD-style Go testing framework). Refer to
+// http://onsi.github.io/ginkgo/ to learn more about Ginkgo.
+
+func TestPostgresVersion(t *testing.T) {
+	RegisterFailHandler(Fail)
+
+	RunSpecs(t, "PostgreSQL Version")
+}

pkg/postgres/version/version.go

@@ -0,0 +1,122 @@
+/*
+Copyright The CloudNativePG Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package version
+
+import (
+	"fmt"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var semanticVersionRegex = regexp.MustCompile(`^(\d\.?)+`)
+
+// Data is a structure used to manage a PostgreSQL version,
+// consisting of two parts: major and minor. For instance,
+// version 10.0 corresponds to a major of 10 and a minor of 0.
+// See: https://www.postgresql.org/support/versioning/
+type Data struct {
+	major uint64
+	minor uint64
+}
+
+// Major gets the major version (i.e. 10)
+func (d Data) Major() uint64 {
+	return d.major
+}
+
+// Minor gets the minor version (i.e. 0)
+func (d Data) Minor() uint64 {
+	return d.minor
+}
+
+// Less is the implementation of the "less than" operator
+func (d Data) Less(other Data) bool {
+	if d.major < other.major {
+		return true
+	} else if d.major > other.major {
+		return false
+	}
+
+	return d.minor < other.minor
+}
+
+// New constructs a version from its components
+func New(major, minor uint64) Data {
+	return Data{
+		major: major,
+		minor: minor,
+	}
+}
+
+// FromTag parse a PostgreSQL version string returning
+// a major version ID. Example:
+//
+//	FromTag("11.2") == (11,2)
+//	FromTag("12.1") == (12,1)
+//	FromTag("13.3.2.1-1") == (13,3)
+//	FromTag("13.4") == (13,4)
+//	FromTag("14") == (14,0)
+//	FromTag("15.5-10") == (15,5)
+//	FromTag("16.0") == (16,0)
+//	FromTag("17beta1") == (17,0)
+//	FromTag("17rc1") == (17,0)
+func FromTag(version string) (Data, error) {
+	if !semanticVersionRegex.MatchString(version) {
+		return Data{},
+			fmt.Errorf("version not starting with a semantic version regex (%v): %s", semanticVersionRegex, version)
+	}
+
+	if versionOnly := semanticVersionRegex.FindString(version); versionOnly != "" {
+		version = versionOnly
+	}
+
+	splitVersion := strings.Split(version, ".")
+
+	majorVersion, err := strconv.Atoi(splitVersion[0])
+	if err != nil {
+		return Data{}, fmt.Errorf("wrong PostgreSQL major in version %v", version)
+	}
+
+	minorVersion := 0
+	if len(splitVersion) > 1 {
+		minorVersion, err = strconv.Atoi(splitVersion[1])
+		if err != nil {
+			return Data{}, fmt.Errorf("wrong PostgreSQL minor in version %v", version)
+		}
+	}
+
+	if majorVersion < 0 || majorVersion > math.MaxInt {
+		return Data{}, fmt.Errorf("wrong PostgreSQL major in version %v", version)
+	}
+
+	if minorVersion < 0 || minorVersion > math.MaxInt {
+		return Data{}, fmt.Errorf("wrong PostgreSQL minor in version %v", version)
+	}
+
+	return Data{
+		major: uint64(majorVersion),
+		minor: uint64(minorVersion),
+	}, nil
+}
+
+// IsUpgradePossible detect if it's possible to upgrade from fromVersion to
+// toVersion
+func IsUpgradePossible(fromVersion, toVersion Data) bool {
+	return fromVersion.major == toVersion.major
+}