SyntaxError: Compiler improperly indenting try/else blocks

[eric-spitler]

After updating to Sanic 21.3 and bringing in sanic-routing, I am running into issues starting the server.

I can't find where the try/else part is being built to propose a solution, but here is a quick example that produces the error.

EXAMPLE APP

from multiprocessing import Process
import time

import requests
from sanic import Blueprint, HTTPResponse, Request, Sanic


async def get(request: Request, *args, **kwargs) -> HTTPResponse:
    print(request.route.path)
    print(args)
    print(kwargs)
    return HTTPResponse()


bp0 = Blueprint(name='base')
bp1 = Blueprint(name='first', url_prefix='/<first>')
bp2 = Blueprint(name='second', url_prefix='/<first>/<second>')
bp3 = Blueprint(name='third', url_prefix='/<first>/<second>/<third>')

bp0.add_route(get, '/')
bp1.add_route(get, '/')
bp2.add_route(get, '/')
bp3.add_route(get, '/')

app = Sanic(name='test')
app.blueprint(bp0)
app.blueprint(bp1)
app.blueprint(bp2)
app.blueprint(bp3)

p = Process(target=app.run, kwargs={'port': 9000})
try:
    p.start()
    time.sleep(2)

    print(requests.get('http://localhost:9000/'))
    print(requests.get('http://localhost:9000/1'))
    print(requests.get('http://localhost:9000/1/2'))
    print(requests.get('http://localhost:9000/1/2/3'))
finally:
    p.terminate()

EXCEPTION

[2021-03-30 23:04:01 +0000] [6332] [ERROR] Experienced exception while trying to serve
Traceback (most recent call last):
  File "/home/my-project/env/lib/python3.7/site-packages/sanic/app.py", line 918, in run
    serve_single(server_settings)
  File "/home/my-project/env/lib/python3.7/site-packages/sanic/server.py", line 725, in serve_single
    serve(**server_settings)
  File "/home/my-project/env/lib/python3.7/site-packages/sanic/server.py", line 554, in serve
    trigger_events(before_start, loop)
  File "/home/my-project/env/lib/python3.7/site-packages/sanic/server.py", line 354, in trigger_events
    loop.run_until_complete(result)
  File "uvloop/loop.pyx", line 1494, in uvloop.loop.Loop.run_until_complete
  File "/home/my-project/env/lib/python3.7/site-packages/sanic/app.py", line 1280, in finalize
    app.router.finalize()
  File "/home/my-project/env/lib/python3.7/site-packages/sanic/router.py", line 179, in finalize
    super().finalize(*args, **kwargs)
  File "/home/my-project/env/lib/python3.7/site-packages/sanic_routing/router.py", line 185, in finalize
    self._render(do_compile)
  File "/home/my-project/env/lib/python3.7/site-packages/sanic_routing/router.py", line 263, in _render
    "exec",
  File "<string>", line 34
    basket['__params__']['first'] = str(basket[0])
         ^
IndentationError: expected an indented block

ERROR
When I make a local modification to router.py to print(self.find_route_src), it reveals this:

def find_route(path, router, basket, extra):
    parts = tuple(path[1:].split(router.delimiter))
    try:
        route = router.static_routes[parts]
        basket['__raw_path__'] = path
        return route, basket
    except KeyError:
        pass
    num = len(parts)
    if num > 0:
        basket[0] = parts[0]
        if num > 1:
            basket[1] = parts[1]
            if num == 3:
                basket[2] = parts[2]
                try:
                    basket['__params__']['first'] = str(basket[0])
                    basket['__params__']['second'] = str(basket[1])
                    basket['__params__']['third'] = str(basket[2])
                except ValueError:
                    ...
                else:
                    basket['__raw_path__'] = '<first>/<second>/<third>'
                    return router.dynamic_routes[('<first>', '<second>', '<third>')], basket
    try:
        basket['__params__']['first'] = str(basket[0])
        basket['__params__']['second'] = str(basket[1])
    except ValueError:
        ...
    else:
        basket['__raw_path__'] = '<first>/<second>'
        return router.dynamic_routes[('<first>', '<second>')], basket
try:
basket['__params__']['first'] = str(basket[0])
except ValueError:
...
else:
basket['__raw_path__'] = '<first>'
return router.dynamic_routes[('<first>',)], basket

[ashleysommer]

Duplicate of #18 (I think).
The fix is being worked on.

For now, please pin Sanic-Router to version 0.4.1 and you won't see this error.

[eric-spitler]

Thanks, that version appears to behave as expected for this case.

I assume there is a reason, but this repository is saniic-router and the PyPi artifact is sanic-routing. Not a big deal but might trip up some users that are trying to find it.

[ahopkins]

Thanks, that version appears to behave as expected for this case.

I assume there is a reason, but this repository is saniic-router and the PyPi artifact is sanic-routing. Not a big deal but might trip up some users that are trying to find it.

Yup. I'm going to make that change

[ahopkins]

Can we close?

[eric-spitler]

Confirmed functional in new releases.