unipdf/internal/e2etest/validate.go
2019-05-16 20:44:51 +00:00

72 lines
1.9 KiB
Go

/*
* This file is subject to the terms and conditions defined in
* file 'LICENSE.md', which is part of this source code package.
*/
package e2etest
import (
"bytes"
"errors"
"fmt"
"os"
"os/exec"
"strings"
"github.com/unidoc/unipdf/v3/common"
)
// To enable ghostscript validation, the path to the binary needs to be specified.
// Set environment variable:
// UNIDOC_GS_BIN_PATH to the path of the ghostscript binary (gs).
var (
ghostscriptBinPath = os.Getenv("UNIDOC_GS_BIN_PATH")
)
// validatePdf a pdf file using Ghostscript, returns an error if unable to execute.
// Also returns the number of output warnings, which can be used as some sort of measure
// of validity, especially when comparing with a transformed version of same file.
func validatePdf(path string, password string) (int, error) {
if len(ghostscriptBinPath) == 0 {
return 0, errors.New("UNIDOC_GS_BIN_PATH not set")
}
common.Log.Debug("Validating: %s", path)
params := []string{"-dBATCH", "-dNODISPLAY", "-dNOPAUSE"}
if len(password) > 0 {
params = append(params, fmt.Sprintf("-sPDFPassword=%s", password))
}
params = append(params, path)
var (
out bytes.Buffer
errOut bytes.Buffer
)
cmd := exec.Command(ghostscriptBinPath, params...)
cmd.Stdout = &out
cmd.Stderr = &errOut
err := cmd.Run()
if err != nil {
common.Log.Debug("%s", out.String())
common.Log.Debug("%s", errOut.String())
common.Log.Error("GS failed with error %s", err)
return 0, fmt.Errorf("GS failed with error (%s)", err)
}
outputErr := errOut.String()
warnings := strings.Count(outputErr, "****")
common.Log.Debug("ERROR: - %d warnings %s", warnings, outputErr)
if warnings > 1 {
if len(outputErr) > 80 {
outputErr = outputErr[:80] // Trim the output.
}
common.Log.Debug("ERROR: Invalid - %d warnings %s", warnings, outputErr)
return warnings, nil
}
// Valid if no error.
return 0, nil
}