您应该使用 for 1.7版本.试试这个:

You should use "_script" for 1.7 version. Try this:

1.7:

"query" : {
    ....
},
"sort" : {
    "_script" : {
        "script" : "doc['city'].value == 'Liverpool' ? 1 : 0",
        "type" : "number",
        "order" : "desc"
    },
    "example_other_field_order":"asc",
    "next_example_field_order":"asc"
}

有关Elasticsearch的最新版本(> = 5.5)，请检查此文档.

For latest version of elasticsearch (>= 5.5) check this doc.