1. lundi 7 décembre 2015 Lavoisier

2. Motivations data sources provided by many partners –heterogeneity of used technologies objectives –reduce complexity / increase maintainability –factorize development efforts –enable accessing data efficiently reliably

3. What is Lavoisier ? an extensible service for providing an unified view of data collected from multiple heterogeneous sources –data is represented in XML –query language is XSLT easy to write cross data sources queries

4. Overview XSLT plugin WS plugin SQL plugin flat file plugin data view manager flat file flat file heterogeneous data sources WS service processXSL SetRP RP QueryRP GetMultipleRP GetRP RDBMS startupnotified Data View refreshed config Data View administrator user (e.g. CIC-portal) getDataView XML Data View about to expire XML Data View XML developer Legend plug-ins Engine operations trigger Data View existant

5. Role: plug-in developer reusable plug-ins –RDBMS –LDAP –Web Services (WSRF) –Run command line –Local XML file –Remote XML file http, https –HTML file (in progress) –Flat file (in progress) specific plug-ins –GGUS –get server public cert. –any java code that build an XML document other plug-ins –index of data views –status of data views –XSL transform –XML filter (SAX-based)

6. Role: administrator (1/2) configure plug-ins –validation of data view –retry rules for each Exception java.lang.Exception is the catch-all exception –argument values static values extracted from another data view (xpath+regex) –plug-in specific config configure data views cache management, depending on characteristics and usage profile of –the data source total amount of data, update frequency, effective latency –the generated view amount of generated data, time-to-live, tolerable latency

7. Role: administrator (2/2) configure data views cache management –cache type in-memory on-disk no cache –cache validity period in case of data source unavailability –set of rules triggering cache update startup time-based notification view access –write –read cache expiration cache dependencies –with or without enforcement of data views consistency combination Reload configuration on the fly (restart only plug-ins with modified configuration) => minimal service interruption Reload configuration on the fly (restart only plug-ins with modified configuration) => minimal service interruption

8. Role: user query data views –through WSRF standard commands with any WSRF-compliant client (e.g. Globus 4) –through server-side XSLT processing only the result of the processing is transferred the result can be –XML –HTML –text

9. Conclusion Maintainability –thanks to unified view of data Factorization of efforts –thanks to separation of roles plug-in developer, administrator, user Data access –efficiency thanks to caching of data views –robustness by keeping previous data view if data source is not available

10. (Some of the) perspectives Move to Apache Maven (improve build process) Schedule plug-ins execution according to memory consumption Add new configuration features –rules to ignore some partial failures, new triggers… Develop new plug-ins –XQuery, rewrite remote XML file plug-in (with JSAGA) …