metaf2xml

metaf2xml parses and decodes aviation routine weather reports (METAR, SPECI, SAO), aerodrome forecasts (TAF), synoptic observations (SYNOP) and observations from buoys (BUOY). The extracted data can be written as XML or passed to a user-defined function (all done in Perl). There are also XSLT style sheets to convert the XML to plain language (text, HTML), or XML with different schemas. A web-based (CGI) user interface can be used to fetch and display current weather data from NOAA, Ogimet, and other sources. The documentation for all Perl scripts and modules (as manual and in other formats) can be generated from the POD in the source code. metaf2xml consists of the following files: metaf2xml/parser.pm contains the code to parse messages Further information can be found in metaf2xml::parser(3pm). metaf2xml/XML.pm contains the code to write the data as XML or pass it to a user-defined function The structure of the XML file probably needs some comment. There were 2 design goals: - one should be able to check the contents of an XML file as strict as possible but with little effort - it should not contain additional data that is not in the original message. DTD is used to check the structure and values of the XML. XSD could have been used, too, but it seemed more effort. DTD cannot restrict the string-value of a node, but only its attributes. Therefore values are assigned to an otherwise empty node with the attribute 'v' (for "value") and, if applicable, 'u' (for "unit"), 'q' (for "qualifier"), and 'rp' and/or 'rn' (possible positive and/or negative deviation from the displayed value due to rounding of the observed value): <wind> <dir v="210" rp="4" rn="5"/> <!-- 205..214° --> <speed v="12" u="KT"/> <!-- 12 kt --> </wind> <RVR> <distance v="325" rp="24" u="M"/> <!-- 325..349 m --> </RVR> <cloudCover v="OVC"/> It is concise, but human-legible as well. Each entry also contains the original string from the message as an attribute named 's' (for "string"): <cloud s="OVC200"> <cloudBase v="20000" u="FT" /> <cloudCover v="OVC" /> </cloud> There are 2 exceptions to the "no additional data" goal: - if a cloud layer is the ceiling, it will have the "isCeiling" tag - if temperature and dewpoint are given it will have 4 tags for the humidity (from 4 different formulars) Both items are considered "hard to compute" in XSL though it certainly is possible. Further information can be found in metaf2xml::XML(3pm). metaf2xml.pl example script to parse messages and write the data as XML requires metaf2xml::parser, metaf2xml::XML Further information can be found in metaf2xml(1). metaf2xml/src2raw.pm contains the code to convert data from different sources of METAR, TAF, SYNOP and BUOY information to the format expected by metaf2xml::parser. Further information can be found in metaf2xml::src2raw(3pm). metafsrc2raw.pl example script to convert data from different sources to the format expected by metaf2xml::parser requires metaf2xml::src2raw Further information can be found in metafsrc2raw(1). metaf.pl (CGI) script to optionally fetch messages from servers, and parse and display them requires metaf2xml::parser, metaf2xml::XML, metaf2xml::src2raw may require curl, xsltproc, and a web server (depending on use) Further information can be found in metaf(1). metaf-html.xsl, metaf-text.xsl two wrapper files for metaf.xsl They define the output method (HTML or text) and then include metaf.xsl. metaf.xsl XML style sheet to transform the contents of the generated XML file All abbreviations are converted to plain language (language support from metaf-lang*.xsl), one message item per line. The output format can be text or HTML. For the text format, the columns are separated by tabulators. metaf-sum-html.xsl, metaf-sum-text.xsl two wrapper files for metaf-sum.xsl They define the output method (HTML or text) and then include metaf-sum.xsl. metaf-sum.xsl XML style sheet to transform the contents of the generated XML file The output is in the form of a summary, one METAR/SYNOP/BUOY per line (plus one for METAR trends). The output format can be text or HTML. metaf-ui.xsl XML style sheet to generate the header, footer and input form for the user interface metaf-fullhtml.xsl, metaf-sum-ui.xsl top level XML style sheets for the user interface They define the output method HTML and then include metaf.xsl or metaf-sum.xsl, respectively, and metaf-ui.xsl. metaf-lang.xsl, metaf-lang-{de,en,es,ru}.xsl XML files with plain language text in several languages Currently output in german, english, spanish, and russian is supported. stations.xml example data file with additional station information, read by metaf.xsl. This is, and will remain, a stub, and will not be extended or updated. metaf.dtd the Document Type Definition for the XML data