[英]How to generate json using Jinja2 Template Engine
我正在尝试从 .xlsx 文件生成一个 json 文件。
到目前为止,我能够从文件中获取数据,但我不确定如何使用 jinja2 将它们放在 json 上。 模板结构有问题。 我该如何解决这个问题?
输出应该是这样的
"Matches": {
"1": {
"time": "19:00",
"teams": "Team 1 - Team 2"
},
"2": {
"time": "21:00",
"teams": "Team 3 - Team 4"
},
...
...
...
}
我的代码是这样的。 显然模板部分是错误的。
from openpyxl import load_workbook
from jinja2 import Template
start_coloumn_of_matches = 3
end_coloumn_of_matches = 20
wb = load_workbook(filename = 'myfile.xlsx')
sheet_ranges = wb['Sheet1']
keys = []
teams = []
times = []
for x in range(start_coloumn_of_matches, end_coloumn_of_matches + 1):
team_column = 'A' + str(x)
time_column = 'D' + str(x)
teams.append(sheet_ranges[team_column].value)
times.append(sheet_ranges[time_column].value)
keys.append(x)
template = Template('''
"Matches": {
{% for key in keys %}
"{{key}}":
{% endfor %}
{
{% for team in teams %}
"teams": "{{team}}",
{% endfor %}
{% for time in times %}
"time": "{{time}}"
{% endfor %}
}
},
''' )
print(template.render(teams = teams, times = times, keys = keys))
手动构建 json 存在意外生成无效 json 字符串的风险。 使用工具来执行此操作更安全,并且可以减少模板的混乱。
如果您使用的是 Jinja 2.9 或更高版本,您可以使用内置的tojson过滤器将 Python 对象*自动转换为 json。
>>> import pprint
>>> # Construct some test data
>>> matches = ['1', '2', '3']
>>> times = ['19:00', '21:00', '23:00']
>>> teams = ['Team 1 - Team 2', 'Team 3 - Team 4', 'Team 5 - Team 6']
>>> # Combine the data structures to match the required output
>>> match_data = [dict(zip(['time', 'team'], pair)) for pair in zip(times, teams)]
>>> combined = {x: y for x, y in zip(matches, match_data)}
>>> pprint.pprint(combined)
{'1': {'team': 'Team 1 - Team 2', 'time': '19:00'},
'2': {'team': 'Team 3 - Team 4', 'time': '21:00'},
'3': {'team': 'Team 5 - Team 6', 'time': '23:00'}}
>>> template = jinja2.Template("""{{ matches | tojson(indent=2) }}""")
>>> print(template.render(matches=combined))
{
"1": {
"team": "Team 1 - Team 2",
"time": "19:00"
},
"2": {
"team": "Team 3 - Team 4",
"time": "21:00"
},
"3": {
"team": "Team 5 - Team 6",
"time": "23:00"
}
}
对于较早的 Jinja 版本,使用 Python 标准库中的json包构建 json,然后在您的模板中呈现 json。
>>> import json
>>> # Serialise our object as json; setting the indent argument gives
>>> # the pretty printed format that we want.
>>> jdata = json.dumps(combined, indent=2)
>>> print(jdata)
{
"1": {
"time": "19:00",
"team": "Team 1 - Team 2"
},
"2": {
"time": "21:00",
"team": "Team 3 - Team 4"
},
"3": {
"time": "23:00",
"team": "Team 5 - Team 6"
}
}
>>> # Pass the json to the template for rendering.
>>> template = jinja2.Template("""{{ matches }}""")
>>> print(template.render(matches=jdata))
{
"1": {
"time": "19:00",
"team": "Team 1 - Team 2"
},
"2": {
"time": "21:00",
"team": "Team 3 - Team 4"
},
"3": {
"time": "23:00",
"team": "Team 5 - Team 6"
}
}
* 过滤器只处理原语 AFAICT; 例如,如果您的数据包含日期时间,则您需要先对它们进行字符串化。
我找到了答案。 将列表压缩到 'matches' 变量中,并像这样构造模板:
template = Template('''
"Matches": {
{% for key, team, time in matches %}
"{{key}}":
{
"teams": "{{team}}",
"time": "{{time}}"
},
{% endfor %}
}
''' )
print(template.render(matches=zip(keys, teams, times)))
我发现这个 Gist 对我有用,对 Python 3 进行了非常小的调整(为打印语句添加括号)。
https://gist.github.com/sevennineteen/4400462
它有一个example.json
文件,用作带有“{{ variable }}”标记的模板,以及一个runner.py
,它组合了模板的输出和输入数据结构。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.