mss - User Interface

The executable for the user interface application is “mss”. A short description of how to start the program is given by the –help option. The program should open the main window of the user interface, from which you can open further windows, including top view, side view and so on.

Configuration for the user interface is located in “mss_settings.json”. In this file, you can specify, for instance, the default WMS URLs for the WMS client, the size of the local image cache (the MSUI caches retrieved WMS images to accelerate repeated retrievals), or the predefined locations that the user can select in the table view.

A few options influencing the appearance of the displayed plots and flight tracks (colours etc.) can be set directly in the user interface (top view and side view).

Configuration of mss

For storage capabilities mss uses the PyFilesystem2 approach. The default data dir is predefined as a directory: ~/mssdata which is the same as osfs://~/mssdata.

PyFilesystem can open a filesystem via an FS URL, which is similar to a URL you might enter in to a browser. FS URLs are useful if you want to specify a filesystem dynamically, such as in a conf file or from the command line.

Syntax for PyFilesystem2 Urls

We have internally implemented PyFilesystem2

FS URLs are formatted in the following way:


The components are as follows:

  • <protocol> Identifies the type of filesystem to create. e.g. osfs, ftp.

  • <username> Optional username.

  • <password> Optional password.

  • <resource> A resource, which may be a domain, path, or both.

Here are a few examples:


Settings file

This file includes configuration settings central to the entire Mission Support User Interface (mss). Among others, define

  • available map projections

  • vertical section interpolation options

  • the lists of predefined web service URLs

  • predefined waypoints for the table view

If you don’t have a mss_settings.json then default configuration is in place.

Store this mss_settings.json in a path, e.g. “$HOME/.config/mss”

The file could be loaded by the File Configuration dialog or by the environment variable MSS_SETTINGS pointing to your mss_settings.json.


    "data_dir": "~/mssdata",
    "filepicker_default": "default",

    "import_plugins": {
        "CSV": ["csv", "", "load_from_csv"],
        "FliteStar": ["fls", "", "load_from_flitestar"],
        "Text": ["txt", "", "load_from_txt"]

    "export_plugins": {
        "CSV": ["csv", "", "save_to_csv"],
        "Text": ["txt", "", "save_to_txt"],
        "KML": ["kml", "", "save_to_kml"],
        "GPX": ["gpx", "", "save_to_gpx"]

    "layout": {
       "topview": [963, 702],
       "sideview": [913, 557],
       "tableview": [1236, 424],
       "immutable": false

    "locations": {
        "EDMO": [48.08, 11.28],
        "Hannover": [52.37, 9.74],
        "Hamburg": [53.55, 9.99],
        "Juelich": [50.92, 6.36],
        "Leipzig": [51.34, 12.37],
        "Muenchen": [48.14, 11.57],
        "Stuttgart": [48.78, 9.18],
        "Wien": [48.20833, 16.373064],
        "Zugspitze": [47.42, 10.98],
        "Kiruna": [67.821, 20.336],
        "Ny-Alesund": [78.928, 11.986]

    "predefined_map_sections": {
        "01 Europe (cyl)": {"CRS": "EPSG:4326",
                            "map": {"llcrnrlon": -15.0, "llcrnrlat": 35.0,
                                    "urcrnrlon": 30.0, "urcrnrlat": 65.0}},
        "02 Germany (cyl)": {"CRS": "EPSG:4326",
                             "map": {"llcrnrlon": 5.0, "llcrnrlat": 45.0,
                                     "urcrnrlon": 15.0, "urcrnrlat": 57.0}},
        "03 Global (cyl)": {"CRS": "EPSG:4326",
                            "map": {"llcrnrlon": -180.0, "llcrnrlat": -90.0,
                                    "urcrnrlon": 180.0, "urcrnrlat": 90.0}},
        "04 Shannon (stereo)": {"CRS": "EPSG:77752350",
                                "map": {"llcrnrlon": -45.0, "llcrnrlat": 22.0,
                                        "urcrnrlon": 45.0, "urcrnrlat": 63.0}},
        "05 Northern Hemisphere (stereo)": {"CRS": "EPSG:77790000",
                                            "map": {"llcrnrlon": -45.0, "llcrnrlat": 0.0,
                                                    "urcrnrlon": 135.0, "urcrnrlat": 0.0}},
        "06 Southern Hemisphere (stereo)": {"CRS": "EPSG:77890000",
                                            "map": {"llcrnrlon": 45.0, "llcrnrlat": 0.0,
                                                    "urcrnrlon": -135.0, "urcrnrlat": 0.0}}

   "new_flighttrack_template": ["Kiruna", "Ny-Alesund"],
   "new_flighttrack_flightlevel": 250,
   "num_interpolation_points": 201,
   "num_labels": 10,

   "WMS_request_timeout": 30,

   "default_WMS": [""],
   "default_VSEC_WMS": [""],
   "default_LSEC_WMS": [""],

   "default_MSCOLAB": [""],
   "WMS_login": {
                  "" : ["youruser", "yourpassword"]
   "MSC_login": {
                 "" : ["youruser", "yourpassword"]

   "MSCOLAB_mailid": "",
   "MSCOLAB_password": ""
Flight track import/export

As the planned flight track has to be quickly communicated to different parties having different desired file formats, MSS supports a simple plugin system for exporting planned flights and importing changed files back in addition to the main FTML format. These filters may be accessed from the File menu of the Main Window.

MSS currently offers several import/export filters in the module, which may serve as an example for the definition of own plugins. Take care that added plugins use different file extensions. They are listed below. The CSV plugin is enabled by default. Enabling the experimental FliteStar text import plugin would require those lines in the UI settings file:

"import_plugins": {
    "FliteStar": ["fls", "", "load_from_flitestar"]

The dictionary entry defines the name of the filter in the File menu. The list specifies in this order the extension, the python module implementing the function, and finally the function name. The module may be placed in any location of the PYTHONPATH or into the configuration directory path.

An exemplary test file format that can be ex- and imported may be activated by:

"import_plugins": {
    "Text": ["txt", "", "load_from_txt"]
"export_plugins": {
    "Text": ["txt", "", "save_to_txt"]

The given plugins demonstrate, how additional plugins may be implemented. Please be advised that several attributes of the waypoints are automatically computed by MSS (for example all time and performance data) and will be overwritten after reading back the file.

Available Export Formats:

"export_plugins": {
    "Text": ["txt", "", "save_to_txt"],
    "KML": ["kml", "", "save_to_kml"],
    "GPX": ["gpx", "", "save_to_gpx"]
Web Proxy

If you are in an area with a very low bandwidth you may consider to use a squid web proxy and add those lines in your mss_settings pointing to the proxy server.

  "proxies": {
    "http": "http://yoursquidproxy:3128",
    "https": "http://yoursquidproxy:3128"


For changing the default cache directory and behaviour to a named directory you can use these parameters. If you use shared directories you may have to solve access rights.

   "wms_cache": "/tmp/.cache/.mss/msui/wms_cache",
   "wms_cache_max_size_bytes": 20971520,
   "wms_cache_max_age_seconds": 432000,

Docking Widgets Configurations


MSS may also roughly estimate the fuel consumption and thus range of the aircraft neglecting weather conditions given a proper configuration file specifying the aircraft performance. Such a file may be loaded using the ‘performance settings’ button in Table View. The aircraft performance is specified using tables given in the JSON format. A basic configuration looks like the following file:

This example file assumes a constant speed of 400 nm/h and a constant fuel consumption of 2900 lbs/h irrespective of flight level changes. The aircraft weight and available fuel are also given, but these may also be adjusted in the GUI after loading.

The columns of the cruise table are aircraft weight (lbs), aircraft altitude (feet), speed (nm/h), and fuel consumption (lbs/h). MSS bilinearily interpolates in aircraft weight and altitude and extrapolates assuming a constant behaviour outside the given data. The climb table specifies the aircraft performance when climbing up from 0 feet altitude, while the descent table specifies the behaviour when descending down to 0 feet altitude. The column headers are aircraft weight (lbs), aircraft altitude (feet), time spent (minutes), distance required (nm), and fuel consumed (lbs). To compute the required data for a flight level change, a bilinear interpolation in the table for current aircraft weight and the two involved altitudes is performed and the difference of the resulting value is used in the calculation.

Satellite Track Docking Widget

The TopView has a docking widget allowing the visualisation of satellite tracks. A web site to generate the data for such tracks is operated by NASA. The data can be downloaded as ASCII file that can be open by the docking widget. An example file is located at docs/samples/satellite_tracks/satellite_predictor.txt.

KML Overlay Docking Widget

The TopView has a docking widget that allows the visualization of KML files on top of the map.

This feature supports all essential elements of KML relevant to MSS’ usage namely:

  • Placemarks (present in Folder/ Document or otherwise)

  • Style (LineStyle & PolyStyle)

  • Geometries defined in KML such as

    • Point

    • LineString

    • LinearRing

    • Polygon (Inner and Outer Rings)

    • MultiGeometries (MultiPoint, MultiLineString, MultiPolygon)

    • Geometry Collection (combination of various types of MultiGeometries)

The KML Support has been enhanced to parse all legal KML Files without crashing, and a clear visualization on the map, with the relevant geometries and styles.

The KML Interface now supports display of multiple KML Files simultaneously, with easy to use Buttons such as ‘Add KML Files’, ‘Remove File’, ‘Select/ Unselect All Files’ for the user’s benefit.

A Check/ Uncheck feature allows users to display/hide individual plots on the map, at the User’s leisure.

A KML Customize Option improves the User Experience by allowing user to customize the colour & linewidth of each of the KML Files displayed, realtime. This allows for better understanding of the map and the plots. (The Customize Option can be accessed for each file, by double clicking on the name of that file in the list.)

The ‘Merge KML Files’ Button allows users to combine all the displayed plotted files, to be combined into a single KML File ‘output.kml’, which will be present in the last working directory of the user.

Have to head out somewhere? Important KML Files open? Close the software with ease of mind. Next time you open your software, all your work will be present, right where you left it! KML Overlay supports Saving Open files so that you can jump back in, anytime!

Test Samples

Curious to test out some KML Files? We have a vibrant sample collection ready just for this!

Example KML Files are located at :

The TopView has a docking widget that allows the visualization of remote sensing related features. It may visualize the position of tangent points of limb sounders and can overlay the flight path with colours according to the relative position of sun, moon, and some planets (to either avoid or seek out alignments). Upon first starting the widget, it is thus necessary to download astronomic positional data (see here for more information). This is automatically performed by the skyfield python package, retrieving the data from public sources of JPL and other US services. The data is stored in the MSS configuration directory and may need to update irregularly.

MSS supports the use of a general file picker to access locations on remote machines facilitating collaboration on campaigns. To enable this feature apply

"filepicker_default": "fs",

to your configuration file. The allowed values are “qt” for QT-based dialogues, “fs” for fs_file_picker-based dialogues supporting remote locations, or “default” for the default dialogues. The default is currently identical to “qt”, but may change in upcoming releases.

With using the “filepicker_default”: “fs” setting you can enable any implemented PyFilesystem2 fs url. Additional to the builtin fs urls we have added optional the webdavfs and sshfs service.

With setting the option “filepicker_default”: “default” you can only access local storages.

"data_dir": "~/mssdata",

Example WMS Server

Some publicly accessible WMS Servers

Automation using the WMS API

Besides using the MSS UI we can use the API of the WMS sercer by a script to create for instance a number of the same plots or several flights or several forecast steps.

The retriever is an example which needs tweaked before using it

# -*- coding: utf-8 -*-


    automation within mss to create for instance a number of the same plots
    for several flights or several forecast steps

    This file is part of mss.

    :copyright: Copyright 2020 Joern Ungermann
    :copyright: Copyright 2020-2021 by the mss team, see AUTHORS.
    :license: APACHE-2.0, see LICENSE for details.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
import sys
import argparse
import datetime
import io
import os
import xml
import requests
from fs import open_fs
import PIL.Image
import matplotlib.pyplot as plt

import mslib
import mslib.utils
from mslib.utils import thermolib
from mslib.utils.units import units
import mslib.msui
import mslib.msui.mpl_map
import mslib.msui.mss_qt

    "bbox": dict(boxstyle="round", facecolor="white", alpha=0.5, edgecolor="none"),
    "fontweight": "bold", "zorder": 4, "fontsize": 6, "clip_on": True}

def load_from_ftml(filename):
    """Load a flight track from an XML file at <filename>.
    _dirname, _name = os.path.split(filename)
    _fs = open_fs(_dirname)
    datasource =
        doc = xml.dom.minidom.parse(datasource)
    except xml.parsers.expat.ExpatError as ex:
        raise SyntaxError(str(ex))

    ft_el = doc.getElementsByTagName("FlightTrack")[0]

    waypoints_list = []
    for wp_el in ft_el.getElementsByTagName("Waypoint"):

        location = wp_el.getAttribute("location")
        lat = float(wp_el.getAttribute("lat"))
        lon = float(wp_el.getAttribute("lon"))
        flightlevel = float(wp_el.getAttribute("flightlevel"))
        comments = wp_el.getElementsByTagName("Comments")[0]
        # If num of comments is 0(null comment), then return ''
        if len(comments.childNodes):
            comments = comments.childNodes[0].data.strip()
            comments = ''

        waypoints_list.append((lat, lon, flightlevel, location, comments))
    return waypoints_list

def main():
    parser = argparse.ArgumentParser(description="""
       This script automatically retrieves and stores a set of plots for the
       configured flights. The configuration is placed within the normal
       MSS frontend JSON file. E.g.

       "automated_plotting": {
           "flights": [
               ["ST25", "01 SADPAP (stereo)", "500,50",
                "2019-07-01T00:00:00Z", "2019-09-01T12:00:00Z"]
           "hsecs": [
                "ecmwf.PVTropo01", "default", "4.0"],
                "ecmwf.ertel_potential_vorticity_pl", "ertel_potential_vorticity_bh", "200.0"]
           "vsecs": [
                "ecmwf.VS_ertel_potential_vorticity_ml", "ertel_potential_vorticity_bh"],
                "ecmwf.TroposphereInversionLayer", ""]

       will plot flight "ST25" with configured map section "01 SADPAP (stereo)" and
       vertical range 500hPa to 50hPa from the given FTML file for init time
       "2019-07-01T00:00:00Z" and valid time "2019-09-01T12:00:00Z". The plots
       are defined in the hsecs (horizontal cross-sections) and vsecs (vertical
       cross-sections) entries given each the URL of the server, the layer name, the style,
       and, for hsec only, the elevation to plot (if necessary).
    parser.add_argument("-v", "--version", help="show version", action="store_true", default=False)
    parser.add_argument("--debug", help="show debugging log messages on console", action="store_true", default=False)
    parser.add_argument("--logfile", help="Specify logfile location. Set to empty string to disable.", action="store",
                        default=os.path.join(mslib.msui.constants.MSS_CONFIG_PATH, "mss_pyui.log"))
    args = parser.parse_args()

    if args.version:
        print("\n            Mission Support System (mss_retriever)\n")
        print("Version:", mslib.__version__)


    config = mslib.utils.config_loader()
    num_interpolation_points = config["num_interpolation_points"]
    num_labels = config["num_labels"]
    tick_index_step = num_interpolation_points // num_labels

    fig = plt.figure()
    for flight, section, vertical, filename, init_time, time in \
        params = mslib.utils.get_projection_params(
        wps = load_from_ftml(filename)
        wp_lats, wp_lons, wp_locs = [[x[i] for x in wps] for i in [0, 1, 3]]
        wp_presss = [thermolib.flightlevel2pressure(wp[2] * units.hft).magnitude for wp in wps]
        for url, layer, style, elevation in config["automated_plotting"]["hsecs"]:
            ax = fig.add_subplot(111, zorder=99)
            bm = mslib.msui.mpl_map.MapCanvas(ax=ax, **(params["basemap"]))

            # plot path and labels
            bm.plot(wp_lons, wp_lats,
                    color="blue", marker="o", linewidth=2, markerfacecolor="red",
                    latlon=True, markersize=4, zorder=100)
            for i, (lon, lat, loc) in enumerate(zip(wp_lons, wp_lats, wp_locs)):
                textlabel = f"{loc if loc else str(i)}   "
                x, y = bm(lon, lat)
                plt.text(x, y, textlabel, **TEXT_CONFIG)

            # retrieve and draw WMS image
            ax_bounds = plt.gca().bbox.bounds
            width, height = int(round(ax_bounds[2])), int(round(ax_bounds[3]))
            bbox = params['basemap']
            req = requests.get(
                url, auth=tuple(config["WMS_login"][url]),
                params={"version": "1.3.0", "request": "GetMap", "format": "image/png",
                        "exceptions": "XML",
                        "crs": config["predefined_map_sections"][section]["CRS"],
                        "layers": layer, "styles": style, "elevation": elevation,
                        "dim_init_time": init_time, "time": time,
                        "width": width, "height": height,
                        "bbox": f"{bbox['llcrnrlat']},{bbox['llcrnrlon']},{bbox['urcrnrlat']},{bbox['urcrnrlon']}"})
            if req.headers['Content-Type'] == "text/xml":
                print(flight, section, vertical, filename, init_time, time)
                print(url, layer, style, elevation)
                print("WMS Error:")
            image_io = io.BytesIO(req.content)
            img =
            bm.imshow(img, interpolation="nearest", origin="upper")


        # prepare vsec plots
        path = [(wp[0], wp[1], for wp in wps]
        lats, lons, _ = mslib.utils.path_points(
            path, numpoints=num_interpolation_points + 1, connection="greatcircle")
        intermediate_indexes = []
        ipoint = 0
        for i, (lat, lon) in enumerate(zip(lats, lons)):
            if abs(lat - wps[ipoint][0]) < 1E-10 and abs(lon - wps[ipoint][1]) < 1E-10:
                ipoint += 1
            if ipoint >= len(wps):

        for url, layer, style in config["automated_plotting"]["vsecs"]:

            # setup ticks and labels
            ax = fig.add_subplot(111, zorder=99)
            p_bot, p_top = [float(x) * 100 for x in vertical.split(",")]
            bbox = ",".join(str(x) for x in (num_interpolation_points, p_bot / 100, num_labels, p_top / 100))
            pres_maj = mslib.msui.mpl_qtwidget.MplSideViewCanvas._pres_maj
            pres_min = mslib.msui.mpl_qtwidget.MplSideViewCanvas._pres_min
            major_ticks = pres_maj[(pres_maj <= p_bot) & (pres_maj >= p_top)]
            minor_ticks = pres_min[(pres_min <= p_bot) & (pres_min >= p_top)]
            labels = [f"{int(_mt / 100)}"
                      if (_mt / 100.) - int(_mt / 100.) == 0 else f"{float(_mt / 100)}" for _mt in major_ticks]
            if len(labels) > 20:
                labels = ["" if _x.split(".")[-1][0] in "975" else _x for _x in labels]
            elif len(labels) > 10:
                labels = ["" if _x.split(".")[-1][0] in "9" else _x for _x in labels]
            ax.set_ylabel("pressure (hPa)")
            ax.set_yticks(minor_ticks, minor=True)
            ax.set_yticks(major_ticks, minor=False)
            ax.set_yticklabels([], minor=True, fontsize=10)
            ax.set_yticklabels(labels, minor=False, fontsize=10)
            ax.set_ylim(p_bot, p_top)
            ax.set_xlim(0, num_interpolation_points)
            ax.set_xticks(range(0, num_interpolation_points, tick_index_step))
                [f"{x[0]:2.1f}, {x[1]:2.1f}"
                 for x in zip(lats[::tick_index_step], lons[::tick_index_step])],
                rotation=25, fontsize=10, horizontalalignment="right")

            # plot path and waypoint labels
            ax.plot(intermediate_indexes, wp_presss,
                    color="blue", marker="o", linewidth=2, markerfacecolor="red",
            for i, (idx, press, loc) in enumerate(zip(intermediate_indexes, wp_presss, wp_locs)):
                textlabel = f"{loc if loc else str(i)} "
                plt.text(idx + 1, press, textlabel, rotation=90, **TEXT_CONFIG)

            # retrieve and draw WMS image
            ax_bounds = plt.gca().bbox.bounds
            width, height = int(round(ax_bounds[2])), int(round(ax_bounds[3]))
            req = requests.get(
                url, auth=tuple(config["WMS_login"][url]),
                params={"version": "1.3.0", "request": "GetMap", "format": "image/png",
                        "exceptions": "XML",
                        "crs": "VERT:LOGP", "layers": layer, "styles": style,
                        "dim_init_time": init_time, "time": time,
                        "width": width, "height": height,
                        "path": ",".join(f"{wp[0]:.2f},{wp[1]:.2f}" for wp in wps),
                        "bbox": bbox})

            if req.headers['Content-Type'] == "text/xml":
                print(flight, section, vertical, filename, init_time, time)
                print(url, layer, style)
                print("WMS Error:")
            image_io = io.BytesIO(req.content)
            img =
            imgax = fig.add_axes(ax.get_position(), frameon=True,
                                 xticks=[], yticks=[], label="ax2", zorder=0)
            imgax.imshow(img, interpolation="nearest", aspect="auto", origin="upper")
            imgax.set_xlim(0, img.size[0] - 1)
            imgax.set_ylim(img.size[1] - 1, 0)


if __name__ == "__main__":