OSError: cannot open resource

[marconimedeiros2]

Im trying to render a SVG file in a headless service (Google Cloud Functions) but this error is showing up when I try to use "render" function:

OSError: cannot open resource

This is a problem with PIL lib.

Anyone can help me with this problem?

[csgoh]

Can you share your code and the full error stack trace? When logging an issue, please provide as much information as possible to help us troubleshoot the problem.

[marconimedeiros2]

Code:

from processpiper.text2diagram import render

input_syntax = """
title: Sample Test Process
colourtheme: BLUEMOUNTAIN
    lane: End User
        (start) as start
        [Enter Keyword] as enter_keyword
        (end) as end
pool: System Search
    lane: Database System
        [Login] as login
        [Search Records] as search_records
        <Result Found?> as result_found
        [Display Result] as display_result
        [Logout] as logout
    lane: Log System
        [Log Error] as log_error

start->login: User \\nAuthenticate
login->enter_keyword: Authenticated
enter_keyword->search_records: Search Criteria
search_records->result_found: Result
result_found->display_result: Yes
display_result->logout->end
result_found->log_error: No
log_error->display_result

footer: Generated by ProcessPiper
"""

render(input_syntax, "my_process_map.png")

Output error:

File "/workspace/main.py" 
render(input_syntax, "my_process_map.svg") 

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/processpiper/text2diagram.py", line 367, in render 
exec(generated_code) 

File "<string>", line 27, in <module> 

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/processpiper/processmap.py", line 461, in draw 
self._set_draw_position() 

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/processpiper/processmap.py", line 297, in _set_draw_position 
self._title.set_draw_position( 

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/processpiper/title.py", line 47, in set_draw_position 
self.width, self.height = painter.get_text_dimension( 
                                        ^^^^^^^^^^^^^^^^^^ 

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/processpiper/painter.py", line 1358, in get_text_dimension _, _, font_width, font_height = self.get_char_width( 

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/processpiper/painter.py", line 378, in get_char_width 
font = ImageFont.truetype(self.get_font_path(text_font), size=text_font_size) 
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/PIL/ImageFont.py", line 807, in truetype 
return freetype(font) 
           ^^^^^^^^

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/PIL/ImageFont.py", line 804, in freetype 
return FreeTypeFont(font, size, index, encoding, layout_engine) 
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/PIL/ImageFont.py", line 244, in __init__ 
self.font = core.getfont( 
                 ^^^^^^^^

Function execution took 110 ms, finished with status: 'crash' 
OSError: cannot open resource 

[csgoh]

It looks like the package cannot find the font file. See this page Installation for additional steps to install font for Ubuntu or Linux.