parse-swissmetnet

Simple PHP package to parse SwissMetNet Open Data strings.

Disclaimer: This library is not official and not affiliated with MeteoSwiss.

Created for usage on api.existenz.ch and indirectly on Aare.guru. As of 2023 in productive use.

SwissMetNet

MeteoSwiss (Bundesamt für Meteorologie und Klimatologie/Federal Office of Meteorology and Climatology) offers a selection of their SwissMetNet measurement data on the opendata.swiss portal.

Measures air temperatures, rain rate, winds, pressure, geopotentials and sunshine duration. Not every station measures every parameter.

Note that most stations measure this 2 meters above ground, but some tower stations locate their sensors higher in the air. The parameters with suffix _tow are measured on tower stations.

Periodicity: 10 minutes.

Licencing restrictions apply by MeteoSwiss. See the Open Data download for detailed informations. You will have to credit any usage of the data with the string "Source: MeteoSwiss".

Getting the data

1. Download the ZIP archive from the Open Data portal.
2. Read the legal and licencing information.
3. Open 1_download_URL.txt.
4. Find the links to the data CSVs (I.e. VQHA80.csv or VQHA98.csv) and metadata TXTs.

Data format 2020

Starting from 2020-10-19 the data format of VQHA80 changed slighty from the original format: They are now valid CSV files, semicolon separated, with a new header line:

Station/Location;Date;tre200s0;rre150z0;sre000z0;gre000z0;ure200s0;tde200s0;dkl010z0;fu3010z0;fu3010z1;prestas0;pp0qffs0;pp0qnhs0;ppz850s0;ppz700s0;dv1towz0;fu3towz0;fu3towz1;ta1tows0;uretows0;tdetows0
TAE;202010191400;11.90;0.00;10.00;326.00;67.50;6.10;26.00;4.30;7.20;957.70;1021.00;1021.20;-;-;-;-;-;-;-;-
COM;202010191400;11.70;0.00;0.00;100.00;68.30;6.10;114.00;1.80;4.30;955.90;1023.60;1023.80;-;-;-;-;-;-;-;-
...

Data format

MeteoSwiss data files VQHA80 are semicolon separated CSVs with a custom header:

MeteoSchweiz / MeteoSuisse / MeteoSvizzera / MeteoSwiss

stn;time;tre200s0;rre150z0;sre000z0;gre000z0;ure200s0;tde200s0;dkl010z0;fu3010z0;fu3010z1;prestas0;pp0qffs0;pp0qnhs0;ppz850s0;ppz700s0;dv1towz0;fu3towz0;fu3towz1;ta1tows0;uretows0;tdetows0
TAE;201911222230;2.4;0.0;0;1;97;1.9;93;5.0;10.8;939.0;1003.3;1001.5;-;-;-;-;-;-;-;-
COM;201911222230;4.1;0.1;0;1;99;4.0;343;3.6;5.0;944.1;1012.9;1011.4;-;-;-;-;-;-;-;-
...

Legay data format

Older data files like VQHA69.csv used the pipe symbol as separators:

MeteoSchweiz / MeteoSuisse / MeteoSvizzera / MeteoSwiss

stn|time|tre200s0|sre000z0|rre150z0|dkl010z0|fu3010z0|pp0qnhs0|fu3010z1|ure200s0|prestas0|pp0qffs0
TAE|201803301120|9.1|1|0.0|87|4.7|1000.1|10.4|73|937.6|1000.2
COM|201803301120|7.3|0|0.2|185|16.9|1005.2|26.6|94|938.3|1005.8
...

Metadata format

The metadata files are free form textual files with space separated tables. Good luck parsing those.

Encoding is ISO-8859-1. This library outputs UTF-8.

Starting from 2021, the metadata is split up into two files: A text file (I.e. VQHA80_en.txt) containing the parameter metadata and a link to a CSV (I.e. ch.meteoschweiz.messnetz-automatisch_en.csv) containing the location metadata.

Installation

composer require cstuder/parse-swissmetnet

Example usage

<?php

require('vendor/autoload.php');

$raw = file_get_contents('https://data.geo.admin.ch/ch.meteoschweiz.messwerte-aktuell/VQHA80.csv');

$data = \cstuder\ParseSwissMetNet\SuperParser::parse($raw);

var_dump($data);

See the bin directory for more working code.

Methods

The parser is intentionally limited: It parses the given string and returns all data which looks valid. It silently skips over any line it doesn't understand.

Values are converted to float. Missing data values are not returned, the values will never be null.

SuperParser::parse(string $raw)

Parses a SwissMetNet data string, tries out all available parsers one after another. If any of them finds anything, returns that data.

Returns an empty row if no parsers find anything. Use at your own risk.

Returns a row of value objects with the keys timestamp, loc, par, val.

DataParser2020::parse(string $raw)

Parses a SwissMetNet data string containing semicolon separated measurements in the 2020 version.

Returns a row of value objects with the keys timestamp, loc, par, val.

DataParser::parse(string $raw)

Parses a SwissMetNet data string containing semicolon separated measurements.

Returns a row of value objects with the keys timestamp, loc, par, val.

LegacyDataParser::parse(string $raw)

Parses an older SwissMetNet data string containing pipe separated measurements.

Returns a row of value objects with the keys timestamp, loc, par, val.

MetadataParser::parse(string $raw)

Parses a SwissMetNet description string containing location and parameter definitions.

Returns two fields: locations and parameters, both containing arrays of StdClass objects with fields such as location coordinates or parameter units.

This parse method behaves like the SuperParser: It tries parsing text files à la VQHA80_en.txt and CSV files à la ch.meteoschweiz.messnetz-automatisch_en.txt. It combines the found metadata into one list.

MetadataParser::parseFromTextFile(string $raw)

Parses a SwissMetNet description string from a file like VQHA80_en.txt containing location and parameter definitions.

Returns two fields: locations and parameters, both containing arrays of StdClass objects with fields such as location coordinates or parameter units.

MetadataParser::parseFromCsvFile(string $raw)

Parses a SwissMetNet description string from a file like ch.meteoschweiz.messnetz-automatisch_en.txt containing location and parameter definitions.

Returns two fields: locations and parameters, both containing arrays of StdClass objects with fields such as location coordinates or parameter units.

Testing

Run composer test to execute the PHPUnit test suite.

Releasing

1. Add changes to the changelog.
2. Add new parsers to the SuperParser.
3. Create a new tag vX.X.X.
4. Push.

License

MIT.

Author

Christian Studer cstuder@existenz.ch, Bureau für digitale Existenz.