Make OAI-PMH check less dependent on availability of externally hosted XSDs.

[Dieter Van Uytvanck]

An alert is triggered when some OAI-PMH XSDs are not available online. To be investigated, since these XSDs seem to be availabe ​off-line too.

from original report:

-> http://www.openarchives.org/OAI/2.0/rights.xsd has become unavailable (or rather, empty). Currently the whole host is unreachable. If it stays that way, I will have to find a workaround.

    { [data not shown]
    * Connection #0 to host alpha.talkbank.org left intact
    http://www.openarchives.org/OAI/2.0/rights.xsd:1: parser error : Document is empty
    /etc/icinga/probes/OAI-PMH/rightsManifest.xsd:21: element include: Schemas parser error : Element {http://www.w3.org/2001/XMLSchema}include: Failed to parse the XML resource http://www.openarchives.org/OAI/2.0/rights.xsd.
    WXS schema /etc/icinga/probes/OAI-PMH.xsd failed to compile
    removed ‘/tmp/tmp.yysI7L1f1o’

    Service performance data:
     time_appconnect=0.000 time_connect=0.121 time_namelookup=0.004 time_pretransfer=0.121 time_redirect=0.000 time_starttransfer=0.255 time_total=0.256 num_connects=1 num_redirects=0

[Menzo Windhouwer]

An alternative for running a validator is to do a sample run of the CLARIN OAI harvester, i.e., this will actually tell us if the endpoint is harvestable by CLARIN. For this a minimal OAI harvester configuration template (where the to be tested endpoint can be inserted) is needed, and a sample/trial runtime so the harvester will stop after a few requests/records.