envoy-cue

CUE schemas for Envoy configurations.

What's Included

Every Envoy config is converted to a corresponding CUE representation by a scheduled nightly job, and committed to the envoy branch in this repo. These updates are periodically merged.

Methodology

The Envoy project defines all its config schemas as Protobuf, but right now Protobuf to CUE conversion is difficult in the case of large trees of .proto files. Instead, we generate CUE from the Go structs defined in go-control-plane, becuase that conversion is a lot simpler, thanks to Go's built in ast package.

Use as a dependency

CUE does not yet have support for package management at the scale of systems like NPM or Go modules. To emulate the transfer and upgrading of CUE modules, git submodules are commonly used.

In the project that uses these CUE definitions:

1. Run cue mod init (if you haven't already done so) a. Edit the cue.mod/module.cue file to contain a module name for the project
2. Run mkdir -p cue.mod/pkg/envoyproxy.io
3. Run git submodule add git@github.com:greymatter-io/envoy-cue cue.mod/pkg/envoyproxy.io/envoy-cue

To update the submodule, run: git submodule update --remote --init

When importing the definitions in the module, use the prefix "envoyproxy.io/envoy-cue" (the module name). For exmaple, importing the RBAC HTTP filter definition would look like:

	import "envoyproxy.io/envoy-cue/spec/extensions/filters/http/rbac/v3"