Groovy HTTPBuilder with multipart/form-data

groovy_multipart_form_data.groovy

import groovy.json.JsonSlurper
import groovyx.net.http.HTTPBuilder
import org.apache.http.entity.mime.MultipartEntityBuilder

import static groovyx.net.http.Method.POST

def url = '<URL>'
def token = '<TOKEN>'
def document = "<PATH_TO_FILE>"
def printErr = System.err.&println

http.request(POST) { req ->
    uri.path = "/v2/upload"
    headers.'Authorization' = token
    requestContentType = 'multipart/form-data'

    def entity = MultipartEntityBuilder
        .create()
        .addTextBody('type', 'driving_licence')
        .addTextBody('side',  'front')
        .addBinaryBody('file', new File(document), org.apache.http.entity.ContentType.IMAGE_PNG, 'driving-licence')
        .build()

    req.entity = entity
    response.failure = { resp ->
        printErr "Document '${document}' upload fail: ${resp.statusLine.statusCode}, message: ${resp.responseBase.entity.content.text}"
        System.exit(-1)
    }
}