Add custom version comparison functions to xmltemplate (#43)

New functions: versionGt, versionGte, versionLt, versionLte

xmltemplate/xmltemplate.go

@@ -6,7 +6,8 @@ import (
 	"github.com/Graylog2/graylog-project-cli/config"
 	"github.com/Graylog2/graylog-project-cli/logger"
 	p "github.com/Graylog2/graylog-project-cli/project"
-	"io/ioutil"
+	"github.com/hashicorp/go-version"
+	"os"
 	"text/template"
 )
 
@@ -49,12 +50,17 @@ func mavenAssemblies(project p.Project) map[string][]Assembly {
 
 func WriteXmlFile(config config.Config, project p.Project, templateFile string, outputFile string) {
 	logger.Info("Generating %v", outputFile)
-	bts, err := ioutil.ReadFile(templateFile)
+	bts, err := os.ReadFile(templateFile)
 	if err != nil {
 		logger.Fatal("Error reading %v: %v", templateFile, err)
 	}
 
-	tmpl, err := template.New(templateFile).Parse(string(bts))
+	serverVersion, err := version.NewVersion(project.Server.Version())
+	if err != nil {
+		logger.Fatal("Error parsing server version %q: %v", project.Server.Version(), err)
+	}
+
+	tmpl, err := template.New(templateFile).Funcs(versionTemplateFuncs(serverVersion)).Parse(string(bts))
 	if err != nil {
 		logger.Fatal("Error parsing template: %v", err)
 	}
@@ -73,7 +79,26 @@ func WriteXmlFile(config config.Config, project p.Project, templateFile string,
 		logger.Fatal("Unable to execute template: %v", err)
 	}
 
-	if err := ioutil.WriteFile(outputFile, buf.Bytes(), 0644); err != nil {
+	if err := os.WriteFile(outputFile, buf.Bytes(), 0644); err != nil {
 		logger.Fatal("Unable to write file %v: %v", outputFile, err)
 	}
 }
+
+func versionTemplateFuncs(serverVersion *version.Version) template.FuncMap {
+	compare := func(compareFunc func(*version.Version) bool) func(any) (bool, error) {
+		return func(versionValue any) (bool, error) {
+			givenVersion, err := version.NewVersion(fmt.Sprintf("%s", versionValue))
+			if err != nil {
+				return false, fmt.Errorf("couldn't parse version %q: %w", versionValue, err)
+			}
+			return compareFunc(givenVersion), nil
+		}
+	}
+
+	return template.FuncMap{
+		"versionGt":  compare(serverVersion.GreaterThan),
+		"versionGte": compare(serverVersion.GreaterThanOrEqual),
+		"versionLt":  compare(serverVersion.LessThan),
+		"versionLte": compare(serverVersion.LessThanOrEqual),
+	}
+}

xmltemplate/xmltemplate_test.go

@@ -0,0 +1,58 @@
+package xmltemplate
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/hashicorp/go-version"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"testing"
+	"text/template"
+)
+
+func TestVersionTemplateFuncs2(t *testing.T) {
+	tests := []struct {
+		serverVersion string
+		function      string
+		version       string
+		rendered      bool
+	}{
+		{"1.2.3", "versionGt", "1.2.3", false},
+		{"1.2.3", "versionGt", "1.3.0", false},
+		{"1.2.3", "versionGt", "1.2.0", true},
+
+		{"1.2.3", "versionGte", "1.2.3", true},
+		{"1.2.3", "versionGte", "1.2.0", true},
+		{"1.2.3", "versionGte", "1.3.0", false},
+
+		{"1.2.3", "versionLt", "1.2.3", false},
+		{"1.2.3", "versionLt", "1.3.0", true},
+		{"1.2.3", "versionLt", "1.2.0", false},
+
+		{"1.2.3", "versionLte", "1.2.3", true},
+		{"1.2.3", "versionLte", "1.2.0", false},
+		{"1.2.3", "versionLte", "1.3.0", true},
+	}
+	for _, test := range tests {
+		testName := fmt.Sprintf("%s-%s-%s-%t", test.function, test.serverVersion, test.version, test.rendered)
+
+		t.Run(testName, func(t *testing.T) {
+			serverVersion, err := version.NewVersion(test.serverVersion)
+			require.Nil(t, err)
+
+			tmpl, err := template.New(testName).Funcs(versionTemplateFuncs(serverVersion)).
+				Parse(fmt.Sprintf(`{{ if %s "%s" }}RENDERED{{ end }}`, test.function, test.version))
+			require.Nil(t, err)
+
+			var out bytes.Buffer
+
+			require.Nil(t, tmpl.Execute(&out, nil))
+
+			if test.rendered {
+				assert.Contains(t, out.String(), "RENDERED")
+			} else {
+				assert.NotContains(t, out.String(), "RENDERED")
+			}
+		})
+	}
+}