【高级技巧】一致性哈希：多服节点的负载分配封装

local ring = {}
local function addNode(nodeName)
    ring[hashOf(nodeName)] = nodeName
end
local function findNode(key)
    local h = hashOf(key)
    local keys = {}
    for k in pairs(ring) do
        keys[#keys + 1] = k
    end
    table.sort(keys)
    for _, k in ipairs(keys) do
        if k >= h then
            return ring[k]
        end
    end
    return ring[keys[1]]
end
local function migrationCount(oldNodes)
    local moved = 0
    for key in pairs(oldNodes) do
        if findNode(key) ~= oldNodes[key] then
            moved = moved + 1
        end
    end
    return moved
end

addNode("node1")
addNode("node2")
addNode("node3")
print(findNode("player_42"))