SmartMet Server
April 13, 2026 · View on GitHub
SmartMet Server is a high-performance, high-availability data and product server for MetOcean data, developed and operated by the Finnish Meteorological Institute (FMI). Written in C++, it has been in operational use since 2008 and powers the FMI Open Data Portal since 2013. The server is INSPIRE compliant.
Capabilities
Input formats:
- GRIB 1 and GRIB 2
- NetCDF
- SQL databases
- QueryData (FMI native format)
Output interfaces and formats:
- OGC WMS 1.3.0, WFS 2.0
- OGC API — Environmental Data Retrieval (EDR)
- JSON, XML, ASCII, HTML
- GRIB 1, GRIB 2, NetCDF
- Raster images (PNG, JPEG, SVG)
The server specializes in on-demand extraction and product generation from gridded weather data (GRIB, NetCDF). It is designed for multi-core use, provides LRU caching, and supports frontend/backend load balancing via the Sputnik engine.
Architecture
The server daemon loads engines (shared stateful modules) and plugins (HTTP interface handlers) at startup. All components share common libraries.
Components
Libraries
| Repository | Description |
|---|---|
| smartmet-library-spine | Core server framework: HTTP handling, plugin/engine management, configuration, thread pool |
| smartmet-library-newbase | Core QueryData format library — the native FMI weather data format with projection and parameter support |
| smartmet-library-macgyver | General utilities: astronomy, caching, datetime parsing, filesystem, charset conversion, CSV, Base64 |
| smartmet-library-gis | GIS operations: coordinate projections, geometry clipping, antimeridian handling, DEM/raster data, PostGIS |
| smartmet-library-giza | Color mapping and SVG rendering: palettes, color trees, color-mapped image generation |
| smartmet-library-locus | Geographic name and location lookup: geocoding queries with multilingual support |
| smartmet-library-imagine | 2D graphics rendering: Bezier curves, affine transforms, color blending, image compositing |
| smartmet-library-imagine2 | Updated 2D graphics rendering library (successor to imagine) |
| smartmet-library-calculator | Time series and area calculation tools for QueryData |
| smartmet-library-delfoi | Oracle database access layer for meteorological observations and flash data |
| smartmet-library-grid-content | Grid support: Content Server, Data Server, and Query Server APIs with Redis, cache, CORBA, and HTTP implementations |
| smartmet-library-grid-files | Unified driver layer for grid file formats: GRIB 1, GRIB 2, NetCDF, QueryData |
| smartmet-library-regression | Regression testing framework for SmartMet tools and libraries |
| smartmet-library-smarttools | Scripting tools for the SmartMet editor, also used by qdtools |
| smartmet-library-textgen | Algorithms for generating weather forecast text from querydata |
| smartmet-library-timeseries | Time series data structures and operations |
| smartmet-library-trajectory | Trajectory calculations for massless particles |
| smartmet-library-trax | High-performance marching-squares contouring: isobands and isolines from 2D gridded data |
| smartmet-library-woml | Weather Object Model (WOML) file reader, used by the frontier renderer |
Engines
Engines are shared stateful modules loaded by the server daemon. They are shared across all plugins.
| Repository | Description |
|---|---|
| smartmet-engine-querydata | QueryData file management and access, with spatial/temporal interpolation and DEM correction |
| smartmet-engine-geonames | Geographic name lookup and geocoding via PostGIS/GeoNames database |
| smartmet-engine-observation | Weather station observation data access |
| smartmet-engine-contour | Isoline and isoband contour generation from gridded data |
| smartmet-engine-gis | GIS data and projection support for plugins |
| smartmet-engine-sputnik | Frontend/backend cluster management and UDP-based load balancing |
| smartmet-engine-grid | Grid support engine: access to Content Server, Data Server, and Query Server APIs |
| smartmet-engine-avi | Aviation weather data (METAR, TAF, SIGMET) access |
| smartmet-engine-authentication | API key authentication and access control |
| smartmet-engine-osm | OpenStreetMap data access |
Plugins
Plugins handle HTTP requests and provide the server's external interfaces.
| Repository | Description |
|---|---|
| smartmet-plugin-timeseries | Time series data retrieval — weather parameters at locations over time |
| smartmet-plugin-wms | OGC Web Map Service 1.3.0 — georeferenced weather map images |
| smartmet-plugin-wfs | OGC Web Feature Service 2.0 — INSPIRE-compliant feature data |
| smartmet-plugin-edr | OGC API — Environmental Data Retrieval |
| smartmet-plugin-download | Bulk data download in GRIB, NetCDF, and QueryData formats |
| smartmet-plugin-frontend | Load-balancing frontend that distributes requests to backend servers |
| smartmet-plugin-backend | Backend handler for frontend-routed requests |
| smartmet-plugin-autocomplete | Location name autocomplete with weather enrichment |
| smartmet-plugin-meta | Metadata about observations (quality codes, observable properties) |
| smartmet-plugin-admin | Server administration: cluster info, cache stats, active requests |
| smartmet-plugin-grid-admin | HTTP interface for grid Content Information Storage administration |
| smartmet-plugin-grid-gui | Browser-based visualization of grid files and content storage |
| smartmet-plugin-avi | Aviation weather data (METAR, TAF, SIGMET) interface |
| smartmet-plugin-cross_section | Vertical cross-section product generation |
| smartmet-plugin-trajectory | Particle trajectory calculation interface |
| smartmet-plugin-textgen | Weather forecast text generation interface |
| smartmet-plugin-q3 | Lua scripting interface for custom weather data queries |
Tools and Applications
| Repository | Description |
|---|---|
| smartmet-qdtools | Comprehensive suite of QueryData handling, conversion, and inspection tools |
| smartmet-qdcontour | Legacy QueryData contouring and map rendering tool |
| smartmet-qdcontour2 | Updated QueryData contouring and map rendering tool |
| smartmet-shapetools | Command-line tools for ESRI shapefile operations |
| smartmet-tools-grid | Grid support server, client, and file inspection programs |
| smartmet-press | PostScript and ASCII product generation from QueryData |
| smartmet-fmitools | FMI-specific meteorological data manipulation tools |
| smartmet-textgenapps | Weather forecast text generation applications |
| smartmet-frontier | SVG weather chart renderer from WOML input |
| smartmet-timezones | Timezone data files: Boost.Date_Time database and packed global shapefile |
| smartmet-fonts | Weather symbol fonts used by SmartMet rendering tools |
| smartmet-roadindex | Road weather index calculations |
| smartmet-roadmodel | Road weather model |
| smartmet-utils | General utility scripts |
Documentation
License
MIT — see LICENSE
Contributing
Bug reports and pull requests are welcome on GitHub. For larger contributions, open an issue for discussion first. A CLA is required — contact us for details.
Contact
- Email: beta@fmi.fi
- GitHub Issues: issues
- FMI Open Source: https://en.ilmatieteenlaitos.fi/open-source-code
- Presentation: https://www.slideshare.net/tervo/smartmet-server-providing-metocean-data