6 comments

[ 2.6 ms ] story [ 23.4 ms ] thread
The first time I came across varlink was the Podman 1.x remote API for client/server communication between clients and a host with the actual Podman installation. However, in Podman 2.x, it was replaced by a RESTful API. Afair, the reason was that the varlink C client was discontinued. Does anyone know if varlink is still actively maintained?
Here are some facts I gathered last time Varlink was discussed:

Varlink is produced by Red Hat, apparently - or by people who use Red Hat things: both examples (DNF, Podman) are Redhat projects.

It seems to be an effort to apply the Interface Definition Language model to UNIX daemons/services/tools by adding a new “standard IO file descriptor” for structured IO using a typed interface, as opposed to the current STDIN/STDOUT/STDERR which are existing un typed byte streams.

Using a new FD instead of agreeing to layer Varlink protocol over STDIO means that existing programs can adopt Varlink without breaking backwards compat or making negotiation even more complicated.

EDIT: Podman removed Varlink https://podman.io/blogs/2020/01/17/podman-new-api.html

(comment deleted)