Add function to add external GPKG

[JakobMiksch]

GeoTIFFs can currently added when they are located externally of the GeoServer data directory.

geoserver-node-client/src/datastore.js

Lines 193 to 219 in b6a495d

	async createGeotiffFromFile (workspace, coverageStore, layerName, layerTitle, filePath) {
	const lyrTitle = layerTitle || layerName;
	const stats = fs.statSync(filePath);
	const fileSizeInBytes = stats.size;
	const readStream = fs.createReadStream(filePath);
	let url = this.url + 'workspaces/' + workspace + '/coveragestores/' +
	coverageStore + '/file.geotiff';
	url += '?filename=' + lyrTitle + '&coverageName=' + layerName;
	const response = await fetch(url, {
	credentials: 'include',
	method: 'PUT',
	headers: {
	Authorization: this.auth,
	'Content-Type': 'image/tiff',
	'Content-length': fileSizeInBytes
	},
	body: readStream
	});
	if (!response.ok) {
	const geoServerResponse = await getGeoServerResponseText(response);
	throw new GeoServerResponseError(null, geoServerResponse);
	}
	// TODO: enforce JSON response or parse XML
	return response.text();
	}

However, this feature is possible with GPKG as well, but is not implemented.

Basic functionality is:

curl \
  -u admin:geoserver \
  -T /path/to/world.gpkg \
  "http://localhost:8080/geoserver/rest/workspaces/klips/datastores/foobar/file.gpkg"

curl \
  -u admin:geoserver \
  -H "Content-type: application/zip" \
  -T /path/to/world.shp.zip \
  "http://localhost:8080/geoserver/rest/workspaces/klips/datastores/foobar/file.shp"