Add 'template' action

COOKBOOK.md

@@ -18,6 +18,7 @@
     * [Common](#common)
       * [`exit`](#exit)
       * [`wait`](#wait)
+      * [`template`](#template)
     * [Input/Output](#inputoutput)
       * [`expect`](#expect)
       * [`print`](#print)
@@ -490,6 +491,71 @@ command "echo 'ABCD'" "Simple echo command"
 
 <a href="#"><img src="https://gh.kaos.st/separator.svg"/></a>
 
+##### `template`
+
+Creates a file from a template. If file already exists, it will be rewritten with the same UID, GID and mode.
+
+▲ _Note that 'template' action will not automatically backup the destination file if it already exists (use `backup` and `backup-restore` actions to preserve the original file). Also, the created file will remain after tests execution if it was created outside the working directory._
+
+You can use the following methods in your templates:
+
+- `Var "name"` - get variable value;
+- `Is "name" "value"` - compare variable value.
+
+Simple example:
+
+```
+# Sysconfig for postgresql service
+
+PG_ENGINE=""
+PG_POSTMASTER=""
+{{ if not .Is "data_dir" "" }}
+PG_DATA="{{ .Var "data_dir" }}/db"
+{{ else }}
+PG_DATA=""
+{{end}}
+PG_LOG=""
+PG_UPLOG=""
+PG_SOCKET_DIR=""
+TIMEOUT=""
+DISABLE_AUTO_NUMA=""
+```
+
+**Syntax:** `template <source> <dest> [file-mode]`
+
+**Arguments:**
+
+* `source` - Path to template file (_String_)
+* `dest` - Destination path (_String_)
+* `file-mode` - Destination file mode (_Integer_) [Optional | 644]
+
+**Negative form:** No
+
+**Example:**
+
+```yang
+command "-" "Create configuration file"
+  template app.template /etc/myapp.conf
+```
+
+```yang
+command "-" "Create configuration file"
+  template app.template /etc/myapp.conf 640
+```
+
+```yang
+command "-" "Replace configuration file"
+  backup /etc/myapp.conf
+  template app.template /etc/myapp.conf 640
+
+...
+
+command "-" "Restore original configuration file"
+  backup-restore /etc/myapp.conf
+```
+
+<a href="#"><img src="https://gh.kaos.st/separator.svg"/></a>
+
 #### Input/Output
 
 Be aware that the output store limited to 2 Mb of data for each stream (`stdout` _and_ `stderr`). So if command generates lots of output data, it better to use `expect` action to working with the output.
@@ -563,6 +629,8 @@ command "echo 'ABCD'" "Simple echo command"
   wait-output 10.0
 ```
 
+<a href="#"><img src="https://gh.kaos.st/separator.svg"/></a>
+
 ##### `output-match`
 
 Checks output with given [regular expression](https://en.wikipedia.org/wiki/Regular_expression).

action/template.go

@@ -0,0 +1,114 @@
+package action
+
+// ////////////////////////////////////////////////////////////////////////////////// //
+//                                                                                    //
+//                         Copyright (c) 2023 ESSENTIAL KAOS                          //
+//      Apache License, Version 2.0 <https://www.apache.org/licenses/LICENSE-2.0>     //
+//                                                                                    //
+// ////////////////////////////////////////////////////////////////////////////////// //
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"text/template"
+
+	"github.com/essentialkaos/bibop/recipe"
+)
+
+// ////////////////////////////////////////////////////////////////////////////////// //
+
+// varWrapper is a recipe wrapper for accessing variables
+type varWrapper struct {
+	r *recipe.Recipe
+}
+
+// ////////////////////////////////////////////////////////////////////////////////// //
+
+// Template is action processor for "template"
+func Template(action *recipe.Action) error {
+	mode := uint64(0644)
+	source, err := action.GetS(0)
+
+	if err != nil {
+		return err
+	}
+
+	dest, err := action.GetS(1)
+
+	if err != nil {
+		return err
+	}
+
+	isSafePath, err := checkPathSafety(action.Command.Recipe, source)
+
+	if err != nil {
+		return err
+	}
+
+	if !isSafePath {
+		return fmt.Errorf("Action uses unsafe path (%s)", source)
+	}
+
+	isSafePath, err = checkPathSafety(action.Command.Recipe, dest)
+
+	if err != nil {
+		return err
+	}
+
+	if !isSafePath {
+		return fmt.Errorf("Action uses unsafe path (%s)", dest)
+	}
+
+	if action.Has(2) {
+		modeStr, _ := action.GetS(1)
+		mode, err = strconv.ParseUint(modeStr, 8, 32)
+
+		if err != nil {
+			return err
+		}
+	}
+
+	tmplData, err := os.ReadFile(source)
+
+	if err != nil {
+		fmt.Errorf("Can't read template %q: %v", source, err)
+	}
+
+	tmpl, err := template.New("").Parse(string(tmplData))
+
+	if err != nil {
+		return fmt.Errorf("Can't parse template %q: %v", source, err)
+	}
+
+	fd, err := os.OpenFile(dest, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, os.FileMode(mode))
+
+	if err != nil {
+		return fmt.Errorf("Can't save template data into %q: %v", dest, err)
+	}
+
+	defer fd.Close()
+
+	vw := &varWrapper{action.Command.Recipe}
+	err = tmpl.Execute(fd, vw)
+
+	if err != nil {
+		return fmt.Errorf("Can't render template %q: %v", source, err)
+	}
+
+	return nil
+}
+
+// ////////////////////////////////////////////////////////////////////////////////// //
+
+// Var returns variable value
+func (vw *varWrapper) Var(name string) string {
+	return vw.r.GetVariable(name, true)
+}
+
+// Is compares variable value
+func (vw *varWrapper) Is(name, value string) bool {
+	return vw.r.GetVariable(name, true) == value
+}
+
+// ////////////////////////////////////////////////////////////////////////////////// //

cli/executor/executor.go

@@ -143,6 +143,7 @@ var handlers = map[string]action.Handler{
 	recipe.ACTION_LIB_EXPORTED:    action.LibExported,
 	recipe.ACTION_PYTHON2_PACKAGE: action.Python2Package,
 	recipe.ACTION_PYTHON3_PACKAGE: action.Python3Package,
+	recipe.ACTION_TEMPLATE:        action.Template,
 }
 
 var temp *tmp.Temp

recipe/tokens.go

@@ -106,6 +106,8 @@ const (
 
 	ACTION_PYTHON2_PACKAGE = "python2-package"
 	ACTION_PYTHON3_PACKAGE = "python3-package"
+
+	ACTION_TEMPLATE = "template"
 )
 
 // ////////////////////////////////////////////////////////////////////////////////// //
@@ -217,4 +219,6 @@ var Tokens = []TokenInfo{
 
 	{ACTION_PYTHON2_PACKAGE, 1, 1, false, false},
 	{ACTION_PYTHON3_PACKAGE, 1, 1, false, false},
+
+	{ACTION_TEMPLATE, 2, 3, false, false},
 }