Get language setting of current node?

Hi iftomkins, 

From your recent posts, it seems that you are building something similar to one of my recent projects: a language selection bar, which allows user to automatically switch to another language by a single click

Just to share what I did,

1) create an endpoint which can update user's profile language and expose itself as JSON.

<#assign result_result = "error" />
<#assign lang = http.request.parameters.name.get("lang", "")?trim />
<#if user.registered && lang?? >
    <#assign update_lang_setting = rest("/users/self/profiles/name/language/set?value=${lang}") />
    <#if update_lang_setting.@status == 'success'>
        <#assign result_result = "success" />
    </#if>
</#if>
{"response":"${result_result}"}

 2) create a component, which calls that endpoint and refreshes the page when user clicks a particular language tab.

LITHIUM.jQuery.ajax({
            type: "GET",
            url: "/plugins/custom/apac/apac/custom.apac.switch_language_edpt?lang=" + new_lang_code,
            dataType: "json",
            success: function (data) {
                if(data.response == "success")    {
                    window.location.reload();
                } else {
                   .........
                }
            },

The output is like 

btw: for anonymous user, you has no user profile to update, you may just need to add  to load http://<your current URL>?profile.language=<new language code>