How to read merged cells in nodejs?

I have an excel file like this

Depart   Air    (Connecting Point)

TPE     NRT     TPE     Null    Null    
                KHH     Null    Null
                CTS     NRT     TPE
                        Null    KHH
                HKD     NRT     TPE
                        Null    KHH
                        KIX     TPE
                OKA     TPE     Null
                        NRT     TPE
                        Null    KHH
                KIX     TPE     Null
                        NRT     TPE
                        Null    KHH
                ASJ     NRT     TPE
                        Null    KHH
                        KIX     TPE
        KIX     TPE     Null    Null
                NRT     TPE     Null
                        KHH     Null
                        KIX     TPE
                        OKA     TPE
                HKD     KIX     TPE
                        NRT     TPE
                        Null    KHH
                ASJ     KIX     TPE
                        NRT     TPE
                        Null    KHH
        OKA     TPE     Null    Null
                NRT     TPE     Null
                        KHH     Null
                        OKA     TPE

I want to convert excel file to 5 object, each row will become one object for example

let object_one = ["TPE"]

let object_two = [{idx:0, name :'NRT'}, {idx:0, name :'KIX'}, {idx:0, name :'OKA'}]

let object_three =[{idx:0, name :'TPE'}] // idx same position with parent index

I know how to read excel file but I don't know how to detect merged cell in nodejs, because my file can be change so i can't hard code here.

via Ihenry