map.py

@callback(
    Output("route-path", "data"),
    Input("map", "click_lat_lng"),
    Input("distance-target", "value"),
    Input("elevation-min", "value"),
    Input("mode-select", "value"),
    State("route-path", "data")
)
def cycles(click_lat_lng, distance_target: Optional[Union[int, float]], elevation_min: Optional[Union[int, float]], mode, path):
    if click_lat_lng is None:
        # prevent the None callbacks is important with the store component.
        # you don't want to update the store for nothing.
        raise PreventUpdate

    nearest_node_id = ox.nearest_nodes(G, click_lat_lng[1], click_lat_lng[0])

    if mode == 1:
        path = {"points": []}

        with rasterio.open("static/gis-data/SRTM_GL3/SRTM_GL3_srtm.vrt") as dataset:
            pt = find_best_loop(G2, nearest_node_id, distance_target, tol=1.0, min_elev=elevation_min, dataset=dataset)
        # path["points"] = path_to_coords_list(G, pt)
        for u, v in zip(pt[:-1], pt[1:]):
            # if there are parallel edges, select the shortest
            data = min(G.get_edge_data(u, v).values(), key=lambda d: d["length"])
            if "geometry" in data:
                # if geometry attribute exists, add all its coords to list
                xs, ys = data["geometry"].xy
                pts = [[ys[i], xs[i]] for i in range(len(xs))]
                path["points"] += pts
            else:
                # otherwise, the edge is a straight line from node to node
                path["points"].append([G.nodes[u]["y"], G.nodes[u]["x"]])

    elif mode == 2:
        if path:
            if "nodes" not in path:
                path = {"points": [], "nodes": [], "last_click_idx": 0}
        else:
            path = {"points": [], "nodes": [], "last_click_idx": 0}

        nearest_node = G.nodes[nearest_node_id]

        if len(path["points"]) == 0:
            path["points"].append([nearest_node["y"], nearest_node["x"]])
        else:
            pt = ox.shortest_path(G, path["nodes"][-1], nearest_node_id)
            # path["points"] = path_to_coords_list(G, pt)
            for u, v in zip(pt[:-1], pt[1:]):
                # if there are parallel edges, select the shortest
                data = min(G.get_edge_data(u, v).values(), key=lambda d: d["length"])
                if "geometry" in data:
                    # if geometry attribute exists, add all its coords to list
                    xs, ys = data["geometry"].xy
                    pts = [[ys[i], xs[i]] for i in range(len(xs))]
                    path["points"] += pts
                else:
                    # otherwise, the edge is a straight line from node to node
                    path["points"].append([G.nodes[u]["y"], G.nodes[u]["x"]])
        path["nodes"].append(nearest_node_id)
        path["last_click_idx"] = len(path["points"])


    return path