Hello OpenWrt community! For the past several months I’ve been working on a project that I hope will prove useful to people and now I’d like to share it with the wider community. Introducing go-ubus-rpc, a Go library and CLI tool to simplify interacting with ubus.
For the developers out there, the library is structured in a way to make it as simple as possible to use. Making a call to ubus mimics the same structure as using ubus on the command line, for example:
func main() {
// create client caller
clientOpts := client.ClientOptions{Username: "root", Password: "admin", URL: "http://10.0.0.1/ubus", Timeout: session.DefaultSessionTimeout}
rpc, _ := client.NewUbusRPC(ctx, &clientOpts)
// make an RPC
uciGetOpts := client.UCIGetOptions{Config: "firewall"} // declare parameters for the call
response, _ := rpc.UCI().Get(uciGetOpts) // make the call
result, _ := uciGetOpts.GetResult(response) // get the typed result object from the response, in this case `result` will be a `UCIGetResult`
}
Every *Opts type has it’s own GetResult function which returns a typed object specific for that call. This library aims to shield users from the dynamic nature of ubus responses and be a consistent, typed layer on top of them with a common pattern to create calls and get responses.
For the admins, it also includes a CLI tool called gur which provides some structure to interacting with ubus, e.g:
$ gur login --url "http://10.0.0.1/ubus" -u root -p 'admin'
$ gur uci get -c dhcp -s lan
{
"sectionArray": [
{
".type": "dhcp",
".name": "lan",
"dhcpv4": "server",
"interface": "lan",
"leasetime": "12h",
"limit": "150",
"ra": "server",
"ra_flags": [
"managed-config",
"other-config"
],
"start": "100"
}
]
}
$ gur uci get -c dhcp -s lan -o ra_flags
{
"option": {
"ra_flags": [
"managed-config",
"other-config"
]
}
}
gur login stores a file with connection info into ~/.go-ubus-rpc/config.json which the CLI will automatically read and use for subsequent calls. If timeout is not specified, it will default to 0 (no expiry). A bit cleaner than manually constructing JSON calls with curl!
The library is currently in an alpha state, it only supports interacting with firewall and dhcp configs at the moment but the logical structure of the library makes it relatively straightforward to add the rest of the default configs. Most of the work still needed is to define all those options in their own structs, but then they should just work as well. A lot of thought and effort went into the logical structure of the library so that it would be easy to add all the configs in, and I’m definitely open to feedback and PRs if anyone is interested in helping to flesh it out!