Recursively loop through a promise?

Question

I am getting a list of droplets from a DigitalOcean API, but the list of droplets are per page.

The response give you the list of droplets on the page and the next page...

I am trying to get the next page of each promise recursively:

getDropletsPerPage(command,firstPage).then((response)=>{

    nextPage= response['nextPage']
    droplets= response['droplets']
​
    getDropletsPerPage(command, nextPage).then((response)=>{

        nextPage= response['nextPage']
        droplets= response['droplets']
​
        getDropletsPerPage(command, nextPage).then((response)=>{

            nextPage= response['nextPage']
            droplets= response['droplets']

            // Repeat until last page..
        })
    })
})

Answer 1

You could use recursion:

const dispatcher = {
    page: firstPage,
    droplets: [],
    execute: function () {
        const self = this;
        return new Promise(function (resolve, reject) {
            getDropletsPerPage(command, this.page).then(function (response) {
                self.page = response['nextPage'];
                self.droplets = self.droplets.concat(response['droplets']);
                if (nextPage === LAST_PAGE) {
                    resolve(true);/* done */
                } else {
                    self.execute().then(function () {
                        resolve(true);
                    });
                }
            });
        });
    }
}
dispatcher.execute().then(function() {
    /* reached last page */
});