Wordpress not available to file using wp-env for xdebug requests

Question

I'm using Wp-env to develop a plugin as it's a pretty robust wrapper for Docker that includes phpunit and xdebug.

However, I have been struggling to get xDebug working.

• From my_plugin directory run wp-env start... await build
• set .vscode/launch.json as per docs:

{
  "name": "Listen for XDebug",
  "type": "php",
  "request": "launch",
  "port": 9003,
  "pathMappings": {
    "/var/www/html/wp-content/plugins/my_plugin": "${workspaceFolder}/"
  }
}

• run wp-env start --xdebug
• open main plugin file and add breakpoint in VS Code and try to Run and Debug
• Result: "PHP Fatal error: Uncaught Error: Call to undefined function plugin_dir_path" (and if I add !defined( 'ABSPATH' ) die(), it is tripped.)

I'm new to this tool so expecting it's a newbie error. Seems like xDebug should be starting at the Wordpress entrypoint, but isn't.

There is one more item of note, though. In wp-env logs:

Xdebug: [Step Debug] Could not connect to debugging client. Tried: host.docker.internal:9003 (through xdebug.client_host/xdebug.client_port) :-(, referer: http://localhost:8888

Answer 1

What the issue ended up being is embarrassing!

I had used the xdebug configuration as the entire launch.json file:

{
  "name": "Listen for XDebug",
  "type": "php",
  "request": "launch",
  "port": 9003,
  "pathMappings": {
    "/var/www/html/wp-content/plugins/my-plugin": "${workspaceFolder}/"
  }
}

As opposed to the correct:

{
  "version": "0.2.0",
  "configurations": [
    {
      "name": "Listen for XDebug",
      "type": "php",
      "request": "launch",
      "port": 9003,
      "pathMappings": {
        "/var/www/html/wp-content/plugins/my-plugin": "${workspaceFolder}/"
      }
    }
  ]
}

Older and wiser!

For other debuggers, this was my path:

The output of adding to index file: xdebug_info(); includes:

[Step Debug] Creating socket for 'host.docker.internal:9003', poll success, but error: Operation now in progress (29).

and

[Step Debug] Could not connect to debugging client. Tried: host.docker.internal:9003 (through xdebug.client_host/xdebug.client_port) :-(

Within the docker container:

/usr/local/etc/php/conf.d/docker-php-ext-xdebug.ini

contains expected: zend_extension=xdebug

In the host, OS X computer:

$ nslookup host.docker.internal
Server:     2001:578:3f::10
Address:    2001:578:3f::10#53

** server can't find host.docker.internal: NXDOMAIN

And in the container, /etc/hosts:

127.0.0.1   localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
172.25.0.5  9cf0413e6c4f

Also /etc/resolv.conf:

nameserver 127.0.0.11
options ndots:0

On the guest, installed apt-get update && apt install dnsutils, for

# nslookup host.docker.internal
Server:     127.0.0.11
Address:    127.0.0.11#53

Non-authoritative answer:
Name:   host.docker.internal
Address: 192.168.65.2

Adding this to my (host computer) hosts file: 127.0.0.1 host.docker.internal did not help.

Wait a minute?

Why does VS Code keep telling me there isn't a launch.json file, then opening it when I direct it to create one? And... see above. : )