Plain

Plain is a web framework for building products with Python.

With the core plain package you can build an app that:

Matches URL patterns to Python views
Handles HTTP requests and responses
Renders HTML templates with Jinja
Processes user input via forms
Has a CLI interface
Serves static assets (CSS, JS, images)
Can be modified with middleware
Integrates first-party and third-party packages
Has a preflight check system

With the official Plain ecosystem packages you can:

Integrate a full-featured database ORM
Use a built-in user authentication system
Lint and format code
Run a database-backed cache
Send emails
Streamline local development
Manage feature flags
Integrate HTMX
Style with Tailwind CSS
Add OAuth login and API access
Run tests with pytest
Run a background job worker
Build staff tooling and admin dashboards

Learn more at plainframework.com.

Source

plain

json.py

 1import datetime
 2import decimal
 3import json
 4import uuid
 5
 6from plain.utils.duration import duration_iso_string
 7from plain.utils.functional import Promise
 8from plain.utils.timezone import is_aware
 9
10
11class PlainJSONEncoder(json.JSONEncoder):
12    """
13    JSONEncoder subclass that knows how to encode date/time, decimal types, and
14    UUIDs.
15    """
16
17    def default(self, o):
18        # See "Date Time String Format" in the ECMA-262 specification.
19        if isinstance(o, datetime.datetime):
20            r = o.isoformat()
21            if o.microsecond:
22                r = r[:23] + r[26:]
23            if r.endswith("+00:00"):
24                r = r.removesuffix("+00:00") + "Z"
25            return r
26        elif isinstance(o, datetime.date):
27            return o.isoformat()
28        elif isinstance(o, datetime.time):
29            if is_aware(o):
30                raise ValueError("JSON can't represent timezone-aware times.")
31            r = o.isoformat()
32            if o.microsecond:
33                r = r[:12]
34            return r
35        elif isinstance(o, datetime.timedelta):
36            return duration_iso_string(o)
37        elif isinstance(o, decimal.Decimal | uuid.UUID | Promise):
38            return str(o)
39        else:
40            return super().default(o)