GET http://bmclapi2.bangbang93.com/optifine/versionList //获取全部版本列表 
GET http://bmclapi2.bangbang93.com/optifine/:mcversion //获取指定版本列表
//Demo
[
    {
        "mcversion": "1.12",  
        "type": "HD_U_C3",    
        "patch": "pre",
        "_id": "5948a92e27faf41b454526aa",
        "__v": 0
    }
]
//下载Optifine
GET http://bmclapi2.bangbang93.com/optifine/:mcversion/:type/:patch
GET http://bmclapi2.bangbang93.com/optifine/1.12/HD_U_C3/pre
//错误提示
{
    "msg": "no such optifine"
}

在minecraftArguments加入--tweakClass optifine.OptiFineTweaker
在libraries加入
[
    {
      "name": "optifine:OptiFine:1.8.8_HD_U_E2"
    },
    {
      "name": "net.minecraft:launchwrapper:1.7"
    }
  ]