Loop clipping Imagecollection by features of a vector in Earth Engine and exporting all tifs

Question

I am looking for a method to clip all the images in an ImageCollection through all the features of a vector (world borders), and then save the resulting tifs in my Google Drive.

So far I wrote this script, which does not work but it gives an idea of what I would like to do. A part for looping over the save with the corresponding filename is missing, as I am not sure how to write it.

var coll = ee.ImageCollection('NOAA/VIIRS/DNB/MONTHLY_V1/VCMSLCFG').select('avg_rad');
var geometry = ee.FeatureCollection("users/gg/gadm");

var loop = function(image, feature){
    var collection_roi = image.clip(feature);

  // missing part to save each output to drive

    }

var stacked = loop(coll, geometry);

Edit:

Using the following code I did manage to create two-argument loop. However, I end up with a list of imagecollections. I am not sure how to save on my drive all the images of each imagecollections in the list.

var coll = ee.ImageCollection('NOAA/VIIRS/DNB/MONTHLY_V1/VCMSLCFG').select('avg_rad');

var geometry = ee.FeatureCollection("users/gg/gadm");

// loop over features and each image of
var loop = function(image){
 var output = geometry.map(function(geom){
 // Clip the image to the polygon geometry
    var ic = image.clip(geom);
    return ic;
})
  return output
};

var outputd = coll.map(loop)

var listOfImages = outputd.toList(outputd.size());

Answer 1

OK, now that I understand what you are trying to do, this is how I'd do it:

var coll = ee.ImageCollection('NOAA/VIIRS/DNB/MONTHLY_V1/VCMSLCFG').select('avg_rad')

var geometry = ee.FeatureCollection("users/gg/gadm");
var name_prop = 'country_na' // replace with the name of the property that holds the polygon name in 'users/gg/gadm'
var date_format = 'yyyyMMdd' // change if you want

// loop over features and each image of
var loop = function(image){
 var output = geometry.map(function(geom){
   // Clip the image to the polygon geometry
   var name = geom.get(name_prop)
   var ic = image.clip(geom);
   var date = ic.date().format(date_format)
   var finalname = ee.String(name).cat('_').cat(date)
   return ic.set('name', finalname).set('system:footprint', geom);
  })
  return output
};

var outputd = coll.map(loop).flatten()
var size = outputd.size().getInfo()
var outputlist = outputd.toList(size)

for (var i=0; i<size; i++) {
  var image = ee.Image(outputlist.get(i))
  var name = image.get('name').getInfo()
  Export.image.toDrive({
    image:image, 
    description:name, 
    folder: 'FOLDER', 
    fileNamePrefix: name, 
    region: image.geometry().getInfo(), 
    scale: 463 // ??
  })
}