Python3: Reportlab Bild - ResourceWarning: nicht geschlossene Datei <_io.BufferedReader name = ...>

Question

Wenn ich einen Komponententest ausführen, bekomme ich Python 3 Unclosed Puffer Fehler auf dem "Logo" Bild im folgenden Code. Wie schließe ich den Logobildpuffer richtig? Bitte beachten Sie, dass die Klasse Image von reportlab.platypus kommt.

Ich habe versucht logo.close() und with Image(logo_path) as logo:, beide funktionieren nicht.

>>python -m unittest tests.test_sample_pdf 

>>/tests/test_sample_pdf.py:51: ResourceWarning: unclosed file <_io.BufferedReader name='/Users/my_prj/statics/my-logo.gif'> 
     get_pdf() 

Source Code

import unittest 
import os 
from io import BytesIO 
from os.path import abspath, dirname 
from reportlab.lib.colors import HexColor 
from reportlab.lib.enums import TA_RIGHT 
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle 
from reportlab.lib.units import inch, cm, mm 
from reportlab.platypus import SimpleDocTemplate, Table, TableStyle, BaseDocTemplate, Paragraph, Image, Spacer 


COL_SORT = [{"headerName": "name", 
      "field": "name", 
      "width": 1000,}] 

def get_pdf(): 
    # setup PDF template 
    buffer = BytesIO() 
    side_margin = 12 
    col_widths = [row['width'] for row in COL_SORT] 
    page_width = sum(col_widths) + side_margin * 3 
    pdf = SimpleDocTemplate(buffer, pagesize=(page_width, 8.5 * inch), rightMargin=side_margin, leftMargin=side_margin, 
          topMargin=side_margin, bottomMargin=side_margin) 
    elements = [] 

    # logo 
    parent_dir = dirname(dirname(abspath(__file__))) 
    logo_path = os.path.join(parent_dir, 'statics', 'my-logo.gif') 
    logo = Image(logo_path) 
    logo.hAlign = 'LEFT' 

    heading_style = ParagraphStyle(name='heading', fontSize=16, leading=20, spaceAfter=0, 
            textColor=HexColor('#ffffff'), backColor=HexColor('#465a81')) 
    heading_right_style = ParagraphStyle(name='heading', fontSize=16, leading=20, spaceAfter=0, 
             textColor=HexColor('#ffffff'), backColor=HexColor('#465a81'), 
             alignment=TA_RIGHT) 
    logo_tbl = Table([[logo]], colWidths=sum(col_widths)) 
    logo_tbl.hAlign = 'LEFT' 
    logo_tbl.setStyle(TableStyle([('BACKGROUND', (0, 0), (-1, -1), HexColor('#B90002'))])) 
    elements.append(logo_tbl) 

    # build PDF 
    pdf.build(elements) 
    pdf_string = buffer.getvalue() 
    buffer.close() 

class TestPDF(unittest.TestCase): 
    def test_pdf(self): 
     get_pdf() 

Answer 1

Es scheint, dass reportlab dass Datei öffnen und schließen Sie das Bild erwartet. Verwenden Sie with open(logo_path, 'rb') as image_fd:.

Diese Problemumgehung löst die Warnung. Ich habe die erwähnte with hinzugefügt und die folgenden Zeilen eingerückt.

def get_pdf(): 
    # setup PDF template 
    buffer = BytesIO() 
    side_margin = 12 
    col_widths = [row['width'] for row in COL_SORT] 
    page_width = sum(col_widths) + side_margin * 3 
    pdf = SimpleDocTemplate(buffer, pagesize=(page_width, 8.5 * inch), rightMargin=side_margin, leftMargin=side_margin, 
          topMargin=side_margin, bottomMargin=side_margin) 
    elements = [] 

    # logo 
    parent_dir = dirname(dirname(abspath(__file__))) 
    logo_path = os.path.join(parent_dir, 'statics', 'nci-logo.gif') 
    with open(logo_path, 'rb') as image_fd:   # edited this line 
     logo = Image(image_fd)       # ... and this line 
     logo.hAlign = 'LEFT' 

     heading_style = ParagraphStyle(name='heading', fontSize=16, leading=20, spaceAfter=0, 
            textColor=HexColor('#ffffff'), backColor=HexColor('#465a81')) 
     heading_right_style = ParagraphStyle(name='heading', fontSize=16, leading=20, spaceAfter=0, 
             textColor=HexColor('#ffffff'), backColor=HexColor('#465a81'), 
             alignment=TA_RIGHT) 
     logo_tbl = Table([[logo]], colWidths=sum(col_widths)) 
     logo_tbl.hAlign = 'LEFT' 
     logo_tbl.setStyle(TableStyle([('BACKGROUND', (0, 0), (-1, -1), HexColor('#B90002'))])) 
     elements.append(logo_tbl) 

     # build PDF 
     pdf.build(elements) 
     pdf_string = buffer.getvalue() 
     buffer.close() 

Ausgang:

$ python -m unittest tests.test_sample_pdf 
. 
---------------------------------------------------------------------- 
Ran 1 test in 0.042s 

OK 

ich das komplette Beispiel gesetzt haben in Github