# FILE(DOWNLOAD....) How to get more informative error messages

**URL:** https://discourse.cmake.org/t/file-download-how-to-get-more-informative-error-messages/11118
**Category:** Usage
**Created:** [June 27, 2024, 2:59pm UTC](https://discourse.cmake.org/t/file-download-how-to-get-more-informative-error-messages/11118 "2024-06-27T14:59:57Z")
**Posts on this page:** 1
**Showing post:** 1

<div class="post-metadata">

### Author: ![imikejackson](https://discourse.cmake.org/user_avatar/discourse.cmake.org/imikejackson/32/301_2.png) [@imikejackson](https://discourse.cmake.org/u/imikejackson)
#### Post date: [June 27, 2024, 2:59pm UTC](https://discourse.cmake.org/t/file-download-how-to-get-more-informative-error-messages/11118/1 "2024-06-27T14:59:57Z")

</div>

As part of our project we generate a CMake file with these contents:

```auto
# -----------------------------------------------------------------------
cmake_policy(SET CMP0012 NEW)
cmake_policy(SET CMP0054 NEW)

# --------------------------------------------------------------------------------------------------
# STARTING 6_5_test_data_1.tar.gz
# Download, Decompress, and possibly copy data archive
# message(STATUS "[DATA DOWNLOAD] 6_5_test_data_1.tar.gz")
# --------------------------------------------------------------------------------------------------
string(TIMESTAMP time_stamp_start %s)
file(DOWNLOAD https://github.com/bluequartzsoftware/simplnx/releases/download/Data_Archive/6_5_test_data_1.tar.gz
              "/Users/mjackson/Workspace1/DREAM3DNX/../DREAM3D_Data/TestFiles/6_5_test_data_1.tar.gz"
              EXPECTED_HASH SHA512=6e21118a882c6a0cc54341eec8928b89ee84ac3a41b1d5b534193f4fabcb49c363db22028055622ad777787be0163cf5525e6c548c11c2c369748feb23031651
              # SHOW_PROGRESS
              STATUS result
              )
string(TIMESTAMP time_stamp_end %s)
list(GET result 1 status)
string(REPLACE "\"" "" status "${status}")

if("${status}" STREQUAL "No error")
  math(EXPR time_diff "${time_stamp_end} - ${time_stamp_start}" OUTPUT_FORMAT DECIMAL) # value is set to "1000"
  file(SIZE "/Users/mjackson/Workspace1/DREAM3DNX/../DREAM3D_Data/TestFiles/6_5_test_data_1.tar.gz" file_size)
  if(NOT "${time_diff}" STREQUAL "0")
    math(EXPR bandwidth "${file_size} / ${time_diff}" OUTPUT_FORMAT DECIMAL) # value is set to "1000"
    message(STATUS "6_5_test_data_1.tar.gz Download Complete: ${bandwidth} bytes/sec")
  else()
    message(STATUS "6_5_test_data_1.tar.gz Download Complete")
  endif()
endif()

```

which is basically repeated for about 50 other files. The issue is that when there is an error we get the following output during the build:

```auto
CMake Error at simplnx_fetch_remote_files.cmake:149 (file):
  file DOWNLOAD cannot compute hash on failed download

    status: [28;"Timeout was reached"]

```

which is sort of helpful. Obviously, I can go into the file and look at that line number and then get which file was the issue. But if this is on a CI machine, I don’t have the luxury. Is there any way to entice the “FILE” command to give a more detailed error message? We are on CMake 3.26.x currently.

Looking at the docs for the “FILE(DOWNLOAD…)” command I see a “LOG” option… except that I can’t even print what gets stored in that variable because CMake errors out before the next line of code is executed (Which would be my message(STATUS “”) line).

I guess I could use “SHOW\_PROGRESS” but that is going to get awful messy with that number of files.

I could also do at `message(STATUS "Download Started"..)` but this is also starting to print a lot of output when it isn’t needed in most cases.

What I’m asking is how to get CMake to print an error like:

```auto
CMake Error at simplnx_fetch_remote_files.cmake:149 (file):
  file DOWNLOAD cannot compute hash on failed download
   URL: https://github.com/bluequartzsoftware/simplnx/releases/download/Data_Archive/6_5_test_data_1.tar.gz
  Result: time out

```

Thoughts?

---

_[View the full topic](https://discourse.cmake.org/t/file-download-how-to-get-more-informative-error-messages/11118)._