Usage

Standalone Usage

Using command line arguements:

chartx-server \
    --port 3000 \
    --origins http://localhost:3000 \
    --dir ./data/charts \
    --log-level info

Or using environment variables

PORT=3000
CORS_ORIGINS=http://localhost:3000
CHART_DIR=./data/charts
LOG_LEVEL=info

Using as an Express Module

chartx-server exports its core modules and routes, allowing it to be embedded into other Express applications.

import express from "express";
import * as chartx from "chartx-server";

chartx.logService.setLevel("info");
chartx.charter.loadCharts("./data/charts");

const app = express();
app.use(chartx.router);
app.listen(3000);

This enables custom authentication, extended routing, chart uploads, integration with existing APIs, and custom processing pipelines.

Assets Served

The server exposes HTTP endpoints for the following assets:

Endpoint	Method	Description
/	GET	Gets chartx info with URLs of charts, glyphs and sprites. Used for loading all available ENCs in chartx web client automatically
/charts	GET	Get chart details like name, DSID url, TileJSON url and vector tiles url. Used for loading ENCs manually in chartx web client
/tiles/<CHART_NAME>/tiles.json	GET	Gets the TileJSON for loading vector tiles in Maplibre GL JS
/tiles/<CHART_NAME>/{z}/{x}/{y}.pbf	GET	Gets vector tiles (.pbf)
/sprites	GET	Gets the sprite ID and url for IHO presentation symbols
/glyphs	GET	Gets the glyphs url and available fontstacks

All assets are directly consumable by chartx web clients.

Configuration Options

CLI Option	ENV	Description
--port	PORT	HTTP server port
--origins	CORS_ORIGINS	Allowed CORS origins
--dir	CHART_DIR	Directory containing ENC charts and updates
--log-level	LOG_LEVEL	Logging verbosity

Configuration can be provided via CLI arguments or environment variables.

Startup Validation

On startup, the application performs the following checks:

1. Verifies that GDAL is installed and supports S-57
2. Verifies that Tippecanoe is available
3. Scans the charts directory for ENC files and updates
4. Generates a content hash for each chart
5. Builds or reuses MBTiles based on detected changes

danger

If GDAL or Tippecanoe are not found, the server fails fast with a descriptive error.