ICU Release Metadata

Copyright (C) 2016, International Business Machines Corporation and others. All Rights Reserved.

Status

This is an experimental file, no formal stability guarantees are in place. Practically, it is the intent to keep the contents and URLs stable as described herein, and they have remained stable.

Introduction

ICU provides machine-readable metadata about ICU releases. This document serves as the documentation for such metadata.

http://icu-project.org/xml/README.md is the canonical URL for this document. See http://icu-project.org for general ICU information.

Note that the URLs given redirect to specific locations, be sure to follow redirects (curl -L for example) to be able to fetch the document.

Scope

The primary scope of the metadata is to answer the following questions:

• What versions of ICU are available? (56.1, 55.1, …)
• When was a particular version released? (ICU4C 56.1 was released 2015-10-07)

There may be additional information available in the metadata files, as these are stabilized this document may be updated.

XML version

The XML version of ICU metadata is located at the canonical URL:

• http://icu-project.org/xml/icumeta.xml

Here is an simplified example snippet of the file:

<icuInfo>
    <icuProducts>
        <icuProduct type="icu4c">
            <releases>
              <release version="57.1" draft="proposed">
                  <dates>
                      <date date="2016-03-31" type="ga"/>
                  </dates>
              </release>
              <release version="56.1">
                <dates>
                  <date date="2015-10-07" type="ga"/>
                </dates>
              </release>
         </icuProduct>
         <!-- icu4j, icu4jni … -->
     </icuProducts>
</icuInfo>

The top level element is <icuInfo>. Under the <icuProducts> element, there is one <icuProduct> entry for the three projects: icu4c, icu4j, and the discontinued <icu4jni>.

Under the <releases> element, there is one <release> element for each ICU release. If the <release> is marked with the draft="proposed" attribute, it notes that the release date is not finalized and this element should NOT be considered as the official release date for ICU.

Under the <dates> element there may be multiple <date> elements. The <date> element with a type="ga" attribute is the only one which may be used to determine the ICU GA (General Availability date). The date= attribute on the <date> element gives the release date, in Year-Month-Day format. For example, 2015-10-07 indicates October 7th, 2015 AD (Gregorian calendar).

The actual XML file contains a reference to an XML DTD and may be validated.

JSON version

The JSON version is new, please give feedback if you have any.

The JSON version of ICU metadata is located at the canonical URL:

• http://icu-project.org/xml/icumeta.json

A simplified view of the data follows:

{
  "//": "Copyright (c) 2016 IBM Corporation and Others, All Rights Reserved.",
  "docs": "http://icu-project.org/xml/README.md",
  "metaversion": 1,
  "projects": {
    "icu4c": {
      "releases": {
        "56.1": {
          "dates": {
            "ga": "2015-10-07"
          }
        },
        "55.1": {
          "dates": {
            "ga": "2015-04-01"
          }
        },
      …  many more versions …
      "proposedReleases": {
         "57.1": {
           "dates": {
           "ga": "2016-03-31"
         }
       }
    },
    …  icu4j, icu4jni …
  }
}

• The // value is a copyright string, it may be ignored for processing
• The docs value is the URL of this document
• The metaversion value is the version number of the metadata document. It's currently “1”.
• The projects hash contains a value for each of the projects (icu4c, icu4j, icu4jni)
• Under a project such as icu4c is the hash releases
• Under the releases hash is a hash for each version, such as 56.1
• under 56.1 there is a hash dates having a key of ga and value with the date in year-month-day format
• proposedReleases (if present) shows any draft (non-final) releases.