In the recent discussions on regarding geodata, Bob and Jason have again brought up a number of good points with regard to standards and interoperability.
Because of limited resources, it is imperative that we as much as possible maintain a unified application, and for instance integrate all the work from India and Vietnam as much as suitable into the core. However, at the same time we need to be mindful of the relatively different roles that DHIS2 as an application can serve. I do very much like how the name emphasizes the use of information for action at local levels. At the same time, DHIS2 is increasingly suited as a platform for a national health observatory and central repository of data for internal reporting and public dissemination (for this, we do still need a way to "publish" certain views of the data without having to log in - and probably a workflow for authorization of public data). One type of data which we would like to serve as a repository for is geodata, in particular the location of health facilities. Jason is quite right that these need to be available in standard formats such as GML (and KML) for easy use and maintenance in clients different from DHIS2. Also, polygon data such as administrative boundaries will almost always come from external sources, and be edited with dedicated GIS software - and for the repository function, we need to preserve the full precision of these data (which often result in quite large amounts of data). On the other hand, there is a need for quick and responsive mapping - which we already have today. For this, the GeoJSON format has proven very suitable, which we should build on. For this to be usable, it's important to radically simplify the files (typically 90% reduction in vertices) and reducing precision in from e.g. 8 decimals to 3. This is different - and for a national repository, I really think a full PostGIS representation of the GeoData with Geoserver on top which can output all kinds of formats in any projection as a webservice is needed. But this need is hardly present in most districts. So we probably need to consider outlining different configurations for different roles of the platform - in the implementation document. Knut _______________________________________________ Mailing list: https://launchpad.net/~dhis2-devs Post to : dhis2-devs@lists.launchpad.net Unsubscribe : https://launchpad.net/~dhis2-devs More help : https://help.launchpad.net/ListHelp
