Feature Request: Support nginx style rewrite rules via rds.RedirectAction

[brirams]

Currently, routes defined via RDS can have a RedirectAction that specify the host and path a matching Route will be redirected to. This works for the cases where one knows what the destination path is up front but not so much for the cases where prefix/suffix rewriting is needed. Nginx does this by allowing one to specify a matching regex on the original path and being able to reference capture groups in the destination:

rewrite ^/foo/(bar)/(.*)$ https://$server_name/$1/$2 permanent;

Ideally, envoy would able to support that kind of referencing but, in lieu of that, being able to at least refer to the original path in a RedirectAction.PathRedirect would help get us most of the way there. The same goes for protocol rewriting.

Context: https://envoyproxy.slack.com/archives/C78M4KW76/p1510966916000159

[srikailash]

Hello @mattklein123, I can work on this issue. Made a sample implementation here : https://github.com/srikailash/envoy/commit/54745c23052032052e4386d05ac38074c08b6cf3 . Once we decide on what exactly is going to be the name in configuration(route.proto) for the regex entries. I can change code accordingly and submit a working pull request. Let me know if that looks good.
Thanks in advance!

[alyssawilk]

Thanks for the patch! @mattklein123 is (mostly) out for the next few weeks so I'd encourage you to do best-effort naming and send out a PR for the data plane change, and your reviewer will help on naming support :-)

[mattklein123]

I think this is done.

[zuercher]

The PR for this was never completed. Reopening.

[zuercher]

For future reference, I think there are people who would like both the ability to regex-rewrites of paths (a la #4403) and regex-rewrites of redirects.

[pepjo]

The pull request was closed 6 days ago. What is the status of this feature?

[harindaka]

Is this not possible yet?

[zuercher]

The original PRs that would have implemented this were never merged. PR #8462 resurrects that implementation.

[cmluciano]

/assign @cmluciano

[DevZenFlow]

This would benefit us too!

[Barborica-Alexandru]

I would love this feature. It would make envoy sidecars extremely usable.

[steeling]

We would like to use this for rewriting hostnames.

Our use case is for routing to specific pods within kubernetes statefulsets. We'd like to setup a an external hostname like 3.abc.xyz.com and reroute to -> myservice-3 in kubernetes.

We could even get by if there was a way to prefix match a VirtualHost and strip the unmatched prefix and add it as a header.

Is there another way to do this that I'm missing?

[sagarkal]

We need this feature as well, since we are replacing nginx with envoy..any ETA on this?

[jespersoderlund]

The referenced issue didn't add this for redirects :(

[esmet]

I may have duplicated this issue in #14348. The associated PR is merged.

If we feel like the above issue is in fact the same thing and the associated PR fixes it, we can close this out.