save.js

const core = require("@actions/core");
const execSync = require("child_process").execSync;

try {
    const skip_saving = core.getInput("skip_saving");
    if (core.getState("CACHE_STATE") != "hit" && skip_saving != "true") {
        var paths = new Array();
        var mixkey = core.getInput("mixkey");
        var keyString = mixkey ? mixkey + "-cache-openwrt" : "cache-openwrt";
        const prefix = core.getInput("prefix");
        if (prefix != "") {
            process.chdir(prefix);
        }

        const toolchain = core.getInput("toolchain");
        if (toolchain == "true") {
            stdout = execSync(
                'git log --pretty=tformat:"%h" -n1 tools toolchain'
            )
                .toString()
                .trim();
            keyString = keyString + "-" + stdout;
            paths.push("staging_dir/host*");
            paths.push("staging_dir/tool*");
        }

        const ccache = core.getInput("ccache");
        if (ccache == "true") {
            stdout = execSync("date +%s").toString().trim();
            keyString = keyString + "-" + stdout;
            paths.push(".ccache");
        }

        const cache = require("@actions/cache");
        console.log(keyString);
        const cacheId = cache.saveCache(paths, keyString).then((res) => {
            if (typeof res !== "undefined" && res) {
                console.log(res, " cache saved");
            }
        });
    }
} catch (error) {
    core.warning(error.message);
}