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go-uci

WORK IN PROGRESS

You're looking at the pre-release documentation for the next major v2 version.

Some things aren't properly flushed out yet and may break at any moment. Use at your own peril.

UCI is OpenWrt's Unified Configuration Interface. It is used to configure OpenWrt router hardware using a simple DSL (and acompanying CLI tools). Configuration files are written into a central directory (/etc/config/*) which basically represents a key/value store.

This project makes it easy to interact with such a config tree by providing a native interface to that KV store. It has no external runtime dependencies.

For now, we only implements a superset of the actual UCI DSL, but improvements (patches or PRs) are very welcome. Refer to Rob Pike's Lexical Scanning in Go for implementation details on the parser/lexer.

Why?

We're currently experimenting with Go binaries on OpenWrt router hardware and need a way to interact with the system configuration. We could have created bindings for libuci, but the turnaround cycle in developing with CGO is a bit tedious. Also, since Go does not compile for our target platforms, we need to resort to GCCGO, which has other quirks.

The easiest solution therefore is a plain Go library, which can be used in Go (with or without CGO) and GCCGO without worrying about interoperability. A library also allows UCI to be used outside of OpenWrt systems (e.g. for provisioning).

Usage

TODO: update example

import "github.com/digineo/go-uci"

func main() {
    // use the default tree (/etc/config)
    if values, ok := uci.Get("system", "@system[0]", "hostname"); ok {
        fmt.Println("hostanme", values)
        //=> hostname [OpenWrt]
    }

    // use a custom tree
    u := uci.NewTree("/path/to/config")
    if values, ok := u.Get("network", "lan", "ifname"); ok {
        fmt.Println("network.lan.ifname", values)
        //=> network.lan.ifname [eth0.2]
    }
    if sectionExists := u.Set("network", "lan", "ipaddr", "192.168.7.1"); !sectionExists {
        _ = u.AddSection("network", "lan", "interface")
        _ = u.Set("network", "lan", "ipaddr", "192.168.7.1")
    }
    u.Commit() // or uci.Revert()
}

See [API documentation][godoc] for more details.

Contributing

Pull requests are welcome, especially if they increase test coverage.

Before submitting changes, please make sure the tests still pass:

$ go test github.com/digineo/go-uci/...

License

MIT License. Copyright (c) 2019 Dominik Menke, Digineo GmbH

https://www.digineo.de

See LICENSE file for details.