当我运行单元测试时,我在以下代码中的“徽标”图像上获得了Python 3未闭合的缓冲区错误.如何正确关闭徽标图像缓冲区?请注意,Image类来自reportlab.platypus.
我已经尝试过logo.close()和使用Image(logo_path)作为徽标:,它们都不起作用.
>>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()
源代码
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()
解决方法:
看来reportlab希望你打开和关闭图像文件.与open(logo_path,’rb’)一起使用作为image_fd:.
此解决方法解决了警告.我已经添加了提到的并缩进了以下行.
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()
输出:
$python -m unittest tests.test_sample_pdf
.
----------------------------------------------------------------------
Ran 1 test in 0.042s
OK
我把完整的例子放在Github中