atlas templates

docker-compose.yml

@@ -32,7 +32,7 @@ services:
       - bash-history:/home/development/commandhistory
 
     environment:
-      # project root directory, used for relative path resolution (e.g. fixtures)
+      # project root directory, used for relative path resolution (e.g. templates)
       PROJECT_ROOT_DIR: *PROJECT_ROOT_DIR
 
     # Uncomment the next four lines if you will use a ptrace-based debugger like C++, Go, and Rust.

internal/lib/mysql.go

@@ -1,31 +1,14 @@
 package lib
 
 import (
-	_ "embed"
-	"fmt"
 	"log"
 	"path/filepath"
-	"text/template"
 )
 
-//go:embed templates/mysql_check.sh.tmpl
-var mysqlCheckScript string
-
-//go:embed templates/mysql_dump.sh.tmpl
-var mysqlDumpScript string
-
-//go:embed templates/mysql_restore.sh.tmpl
-var mysqlRestoreScript string
-
 func EnsureMySQLAvailable(namespace string, config MySQLConfig) error {
 	log.Printf("Checking if MySQL is available in namespace '%s'...", namespace)
 
-	tmpl, err := template.New("mysql_check").Parse(mysqlCheckScript)
-	if err != nil {
-		return fmt.Errorf("failed to parse MySQL check script template: %w", err)
-	}
-
-	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, tmpl, config)
+	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, GetTemplateAtlas().MySQLCheck, config)
 }
 
 func DumpMySQL(namespace string, dryRun bool, config MySQLConfig) error {
@@ -45,12 +28,7 @@ func DumpMySQL(namespace string, dryRun bool, config MySQLConfig) error {
 		DumpFileDir: filepath.Dir(config.DumpFile),
 	}
 
-	tmpl, err := template.New("mysql_backup").Parse(mysqlDumpScript)
-	if err != nil {
-		return fmt.Errorf("failed to parse MySQL backup script template: %w", err)
-	}
-
-	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, tmpl, data)
+	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, GetTemplateAtlas().MySQLDump, data)
 }
 
 func RestoreMySQL(namespace string, dryRun bool, config MySQLConfig) error {
@@ -60,10 +38,5 @@ func RestoreMySQL(namespace string, dryRun bool, config MySQLConfig) error {
 	}
 	log.Printf("Restoring MySQL database '%s' in namespace '%s'...", config.DB, namespace)
 
-	tmpl, err := template.New("mysql_backup").Parse(mysqlRestoreScript)
-	if err != nil {
-		return fmt.Errorf("failed to parse MySQL restore script template: %w", err)
-	}
-
-	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, tmpl, config)
+	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, GetTemplateAtlas().MySQLRestore, config)
 }

internal/lib/postgres.go

@@ -1,31 +1,14 @@
 package lib
 
 import (
-	_ "embed"
-	"fmt"
 	"log"
 	"path/filepath"
-	"text/template"
 )
 
-//go:embed templates/postgres_check.sh.tmpl
-var postgresCheckScript string
-
-//go:embed templates/postgres_dump.sh.tmpl
-var postgresDumpScript string
-
-//go:embed templates/postgres_restore.sh.tmpl
-var postgresRestoreScript string
-
 func EnsurePostgresAvailable(namespace string, config PostgresConfig) error {
 	log.Printf("Checking if Postgres is available in namespace '%s'...", namespace)
 
-	tmpl, err := template.New("postgres_check").Parse(postgresCheckScript)
-	if err != nil {
-		return fmt.Errorf("failed to parse Postgres check script template: %w", err)
-	}
-
-	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, tmpl, config)
+	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, GetTemplateAtlas().PostgresCheck, config)
 }
 
 func DumpPostgres(namespace string, dryRun bool, config PostgresConfig) error {
@@ -45,12 +28,7 @@ func DumpPostgres(namespace string, dryRun bool, config PostgresConfig) error {
 		DumpFileDir:    filepath.Dir(config.DumpFile),
 	}
 
-	tmpl, err := template.New("postgres_backup").Parse(postgresDumpScript)
-	if err != nil {
-		return fmt.Errorf("failed to parse Postgres backup script template: %w", err)
-	}
-
-	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, tmpl, data)
+	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, GetTemplateAtlas().PostgresDump, data)
 }
 
 func RestorePostgres(namespace string, dryRun bool, config PostgresConfig) error {
@@ -60,10 +38,5 @@ func RestorePostgres(namespace string, dryRun bool, config PostgresConfig) error
 	}
 	log.Printf("Restoring Postgres database '%s' in namespace '%s'...", config.DB, namespace)
 
-	tmpl, err := template.New("postgres_restore").Parse(postgresRestoreScript)
-	if err != nil {
-		return fmt.Errorf("failed to parse postgres restore script template: %w", err)
-	}
-
-	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, tmpl, config)
+	return KubectlExecTemplate(namespace, config.ExecResource, config.ExecContainer, GetTemplateAtlas().PostgresRestore, config)
 }

internal/lib/script_exec_test.go

@@ -1,17 +1,12 @@
 package lib_test
 
 import (
-	_ "embed"
 	"testing"
-	"text/template"
 
 	"github.com/allaboutapps/backup-ns/internal/lib"
 	"github.com/stretchr/testify/require"
 )
 
-//go:embed templates/test_trap.sh.tmpl
-var testTrapScript string
-
 func TestTrap(t *testing.T) {
 	// Create template data with computed fields
 	type templateData struct {
@@ -23,10 +18,7 @@ func TestTrap(t *testing.T) {
 		Cmd:      "sleep 0.1",
 	}
 
-	tmpl, err := template.New("traptest").Parse(testTrapScript)
-	require.NoError(t, err)
-
-	require.NoError(t, lib.KubectlExecTemplate("generic-test", "deployment/writer", "debian", tmpl, data))
+	require.NoError(t, lib.KubectlExecTemplate("generic-test", "deployment/writer", "debian", lib.GetTemplateAtlas().TestTrap, data))
 	// succeess testfile exists!
 	require.NoError(t, lib.KubectlExecCommand("generic-test", "deployment/writer", "debian", "test -f /tmp/trap_test.txt"))
 }
@@ -42,10 +34,7 @@ func TestTrapCommandFail(t *testing.T) {
 		Cmd:      "thiscommanddoesnotexist",
 	}
 
-	tmpl, err := template.New("traptest").Parse(testTrapScript)
-	require.NoError(t, err)
-
-	require.Error(t, lib.KubectlExecTemplate("generic-test", "deployment/writer", "debian", tmpl, data))
+	require.Error(t, lib.KubectlExecTemplate("generic-test", "deployment/writer", "debian", lib.GetTemplateAtlas().TestTrap, data))
 	// trap has deleted file
 	require.Error(t, lib.KubectlExecCommand("generic-test", "deployment/writer", "debian", "test -f /tmp/trap_test.txt"))
 }

internal/lib/templates.go

@@ -0,0 +1,54 @@
+package lib
+
+import (
+	"embed"
+	"log"
+	"text/template"
+)
+
+//go:embed templates
+var templates embed.FS
+
+type TemplateAtlas struct {
+	MySQLCheck      *template.Template
+	MySQLDump       *template.Template
+	MySQLRestore    *template.Template
+	PostgresCheck   *template.Template
+	PostgresDump    *template.Template
+	PostgresRestore *template.Template
+	TestTrap        *template.Template
+}
+
+var templateAtlas TemplateAtlas
+
+func init() {
+	tmpl, err := template.ParseFS(templates, "templates/*.sh.tmpl")
+
+	if err != nil {
+		log.Fatal("Failed to parse templates/*.sh.tmpl templates.")
+	}
+
+	templateAtlas = TemplateAtlas{
+		MySQLCheck:      ensureChildTemplate(tmpl, "mysql_check.sh.tmpl"),
+		MySQLDump:       ensureChildTemplate(tmpl, "mysql_dump.sh.tmpl"),
+		MySQLRestore:    ensureChildTemplate(tmpl, "mysql_restore.sh.tmpl"),
+		PostgresCheck:   ensureChildTemplate(tmpl, "postgres_check.sh.tmpl"),
+		PostgresDump:    ensureChildTemplate(tmpl, "postgres_dump.sh.tmpl"),
+		PostgresRestore: ensureChildTemplate(tmpl, "postgres_restore.sh.tmpl"),
+		TestTrap:        ensureChildTemplate(tmpl, "test_trap.sh.tmpl"),
+	}
+}
+
+func ensureChildTemplate(template *template.Template, name string) *template.Template {
+	tmpl := template.Lookup(name)
+
+	if tmpl == nil {
+		log.Fatalf("Template '%s' not found.", name)
+	}
+
+	return tmpl
+}
+
+func GetTemplateAtlas() TemplateAtlas {
+	return templateAtlas
+}

internal/lib/templates/README.md

@@ -0,0 +1,3 @@
+# `templates`
+
+These are the scripts templates that the go application runs within the remote resource (the container hosting the db or just having the db utils) during backup and restore.