Tool:Iw

Toolforge tools
Website	https://iw.toolforge.org
Description	Redirect to Toolforge tools
Keywords	interwiki
Maintainer(s)	BryanDavis (View all)
License	GNU General Public License 3.0 or later
Admin log	Tools.iw/SAL

Iw is a redirection service designed to be used for creating interwiki links to Toolforge tools.

Interwiki links are used in many Wikimedia wikis including Wikitech to create links to Toolforge tools. The interwiki system is prefix based and does not currently robustly support a single interwiki prefix targeting multiple hosts. This creates a problem for migration of Toolforge tools from path based routing (https://tools.wmflabs.org/$TOOL) to host based routing (https://$TOOL.toolforge.org/). The iw tool is an attempt to bridge this gap by providing a prefix (https://iw.toolforge.org/) with a backend that will redirect to other Toolforge tools.

On-wiki usage

See meta:Interwiki map for configuration management. Request for current configuration.

Prefix	Target URL
toolforge	https://iw.toolforge.org/$1
toollabs	https://iw.toolforge.org/$1

Tool setup

Iw is an Ingress only tool running on Toolforge's Kubernetes cluster. "Ingress only" means that the tool does not run any application code, but instead does all of its work using Kubernetes Ingress objects to configure the Kubernetes cluster's nginx ingress controller.

$ ssh login.toolforge.org
$ become iw
$ cd iw
$ vim ingress.yaml
$ kubectl apply --validate=true -f ingress.yaml

---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: iw-domain
  namespace: tool-iw
  labels:
    name: iw-domain
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/use-regex: "true"
    # Redirect to the host based route for the target tool at *.toolforge.org
    nginx.ingress.kubernetes.io/temporal-redirect: https://$1.toolforge.org/$3$is_args$args
spec:
  rules:
    - host: iw.toolforge.org
      http:
        paths:
          - backend:
              service:
                name: unused
                port:
                  number: 8000
            path: /([A-Za-z0-9_-]+)(/|$)(.*)
            # Example path: /bash/random
            # Captures:
            # $0 == /bash/random
            # $1 == bash
            # $2 == /
            # $3 == random
            pathType: ImplementationSpecific
---
# T257104: ingress to handle https://iw.toolforge.org/
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: iw-root
  namespace: tool-iw
  labels:
    name: iw-root
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/temporal-redirect: https://toolforge.org/$is_args$args
spec:
  rules:
    - host: iw.toolforge.org
      http:
        paths:
          - backend:
              service:
                name: unused
                port:
                  number: 8000
            path: /
            pathType: Prefix

Testing

You can run the following script to verify URLs redirect as expected.

import requests

urls = {
    '/': 'https://wikitech.wikimedia.org/wiki/Portal:Toolforge',
    '/test': 'https://test.toolforge.org/',
    '/test/path/': 'https://test.toolforge.org/path/',
    '/test/?query=foo': 'https://test.toolforge.org/?query=foo'
}

for iw, expected in urls.items():
    iw_url = 'https://iw.toolforge.org' + iw
    req = requests.get(iw_url)
    assert req.url == expected, f'{iw_url} redirected to {expected}'
    print('.', end='')

print('')
print('All URLs redirected properly')