databricks-cli/libs/template/execute.go

104 lines
2.7 KiB
Go

package template
import (
"os"
"path/filepath"
"strings"
"text/template"
)
// Executes the template by appling config on it. Returns the materialized config
// as a string
func executeTemplate(config map[string]any, templateDefination string) (string, error) {
// configure template with helper functions
tmpl, err := template.New("foo").Funcs(HelperFuncs).Parse(templateDefination)
if err != nil {
return "", err
}
// execute template
result := strings.Builder{}
err = tmpl.Execute(&result, config)
if err != nil {
return "", err
}
return result.String(), nil
}
// TODO: allow skipping directories
func generateDirectory(config map[string]any, parentDir, nameTempate string) (string, error) {
dirName, err := executeTemplate(config, nameTempate)
if err != nil {
return "", err
}
err = os.Mkdir(filepath.Join(parentDir, dirName), 0755)
if err != nil {
return "", err
}
return dirName, nil
}
func generateFile(config map[string]any, parentDir, nameTempate, contentTemplate string) error {
// compute file content
fileContent, err := executeTemplate(config, contentTemplate)
// We do a substring match here because on errors the template library prepends
// some additional information about the callsite from which the ErrSkipThisFile
// error was returned
if err != nil && strings.Contains(err.Error(), ErrSkipThisFile.Error()) {
return nil
}
if err != nil {
return err
}
// create the file by executing the templatized file name
fileName, err := executeTemplate(config, nameTempate)
if err != nil {
return err
}
f, err := os.Create(filepath.Join(parentDir, fileName))
if err != nil {
return err
}
// write to file the computed content
_, err = f.Write([]byte(fileContent))
return err
}
func WalkFileTree(config map[string]any, templatePath, instancePath string) error {
enteries, err := os.ReadDir(templatePath)
if err != nil {
return err
}
for _, entry := range enteries {
if entry.IsDir() {
// case: materialize a template directory
dirName, err := generateDirectory(config, instancePath, entry.Name())
if err != nil {
return err
}
// recusive generate files and directories inside inside our newly generated
// directory from the template defination
err = WalkFileTree(config, filepath.Join(templatePath, entry.Name()), filepath.Join(instancePath, dirName))
if err != nil {
return err
}
} else {
// case: materialize a template file with it's contents
b, err := os.ReadFile(filepath.Join(templatePath, entry.Name()))
if err != nil {
return err
}
contentTemplate := string(b)
fileNameTemplate := entry.Name()
err = generateFile(config, instancePath, fileNameTemplate, contentTemplate)
if err != nil {
return err
}
}
}
return nil
}