kong.request.get_uri_captures() has no data

[cs1hsb]

Hi

Trying to use kong.request.get_uri_captures() as described here and here

(I think ngx.ctx.router_matches is out of date?)

I am doing this using a python plugin running in a KONG docker container.

When I try and call kong.request.get_uri_captures() I get the KONG error:

023/05/26 07:34:15 [error] 1256#0: *610 [kong] mp_rpc.lua:347 [py-test-capture-plugin] no data, client: 192.168.224.1, server: kong, request: "GET /apiv1/students/2000 HTTP/1.1", host: "localhost:8000"

My plugin works fine for other operations and functionality and the matched group regex path I have configured for the Route in kong.yml seems to correctly pass through requests to the plugin.

(I'm sure I'm also getting the mapping from lua to pyhon wrong for the return captures table but I would have thought I would progress past kong.request.get_uri_captures() in my plugin...)

I'm using kong:3.3.0-alpine docker hub image and I can see that kong-python-pluginserver 0.33 is running in the container.

Running KONG on debug with CMD ["kong", "start", "--vv"] hasn't given me any clues that I can see either.

Any help/advice greatly appreciated. thanks :)

FILES

py-test-capture-plugin.py

#!/usr/bin/env python3
import os
import kong_pdk.pdk.kong as kong

Schema = (
    {"message": {"type": "string"}},
)

version = '0.1.0'
priority = 0

class Plugin(object):
    def __init__(self, config):
        self.config = config

    def access(self, kong: kong.kong):
        try:
            kong.log("--------------------------------------------------------------------")


            kong.log("--------------------------")
            # errors here
            captures = kong.request.get_uri_captures()
            kong.log("--------------------------")
            named = captures.named
            kong.log("--------------------------")
            kong.log(str(named.items()));
            kong.log("--------------------------")

            # below all works when above code commented out
            kong.service.request.set_header("x-hello-from-python", kong.request.get_path())
            kong.service.request.set_header("x-python-pid", str(os.getpid()))
            params = {"wooId" : "132323323", "cardId" : "888888"}
            kong.log("--------------------------------------------------------------------")
            kong.service.request.set_query(params)
        except Exception as ex:
            kong.log.error(ex)


# add below section to allow this plugin optionally be running in a dedicated process
if __name__ == "__main__":
    from kong_pdk.cli import start_dedicated_server
    start_dedicated_server("hello-plugin", Plugin, version, priority, Schema)

kong.yml

_format_version: "3.0"

_transform: true

services:
  - name: test-api-1
    url: http://postman-echo.com/get
    plugins:
    routes:
      - name: test-api-1-students
        paths:
          - ~/apiv1/students/(?<studentid>\d+)
        plugins:
          - name: py-test-capture-plugin

Dockerfile-kong

FROM kong:3.3.0-alpine
USER root
# Example for Python
# PYTHONWARNINGS=ignore is needed to build gevent on Python 3.9
RUN apk update && \
    apk add python3 py3-pip python3-dev musl-dev libffi-dev gcc g++ file make && \
    PYTHONWARNINGS=ignore pip3 install kong-pdk

docker-compose.yml

version: '3.1'

services:

  kong:
    container_name: kong
    build:
      dockerfile: Dockerfile-kong
    volumes:
      # declarative db-less config
      - ./kong/config:/etc/kong/declarative
      # custom plugins
      - ./kong/py-plugins:/opt/conf/kong-py-plugins
    environment:
      # Use the config defined in kong.yml
      KONG_DATABASE: "off"
      KONG_DECLARATIVE_CONFIG: /etc/kong/declarative/kong.yml
      # Show all output in the terminal when running with Docker
      KONG_PROXY_ACCESS_LOG: /dev/stdout
      KONG_ADMIN_ACCESS_LOG: /dev/stdout
      KONG_PROXY_ERROR_LOG: /dev/stderr
      KONG_ADMIN_ERROR_LOG: /dev/stderr
      KONG_ADMIN_LISTEN: 0.0.0.0:8001, 0.0.0.0:8444 ssl
      # Enable the py plugin server
      KONG_PLUGINSERVER_NAMES: py
      KONG_PLUGINSERVER_PY_SOCKET: /usr/local/kong/python_pluginserver.sock
      KONG_PLUGINSERVER_PY_START_CMD: "/usr/bin/kong-python-pluginserver --no-lua-style --plugins-directory /opt/conf/kong-py-plugins"
      KONG_PLUGINSERVER_PY_QUERY_CMD: "/usr/bin/kong-python-pluginserver --no-lua-style --plugins-directory /opt/conf/kong-py-plugins --dump-all-plugins"
      # Allow plugins to be used. The plugin name is your py file name
      KONG_PLUGINS: "bundled, py-test-capture-plugin"
    ports:
      - 8000:8000
      - 8443:8443
      - 8001:8001
      - 8444:8444
    networks:
      - api-network

networks:
    api-network:

Test request

 curl -i --request GET 'http://localhost:8000/apiv1/students/2000'

[n99]

Hi - could someone help here please?
Many thanks 🙏