""" A custom service that just translates IVOIDs (in the remaining url segments) to VOResource XML. """ import os import re from gavo import base from gavo import formal from gavo import svcs from gavo import utils from gavo import web from gavo.protocols import oaiclient from gavo.registry.model import VOR from gavo.utils import stanxml oaicore, _ = utils.loadPythonModule( os.path.join(base.getConfig("inputsDir"), "rr", "res", "oaicore")) class ResourceWrapper(VOR.Resource): """A ri:Resource element with unparsed content. """ name_ = "Resource" _a_xsi_type = None _prefix = "ri" _additionalPrefixes = frozenset(["xsi"]) def addChild(self, child): self._children.append(oaicore.RawXML(child)) def mungeOAIXML(oaixml): """turns oaixml as generated by vorgrammar into a proper VOResource record. oaixml isn't valid XML as the namespace declarations are missing. Hence, we hack things a bit. """ openingElement = re.search("]*)>", oaixml) resType = re.search('xsi:type="([^"]*)"', openingElement.group(1)).group(1) # this doesn't *actually* parse attributes (e.g., opening and closing # quote mismatches are not detected), but it's good enough for plausible # attributes of ri:Resource attrPairRE = re.compile(r"\s([a-zA-Z-]+)\s*=[\"']([^\"']+)[\"']") nonNSAttrs = dict((m.group(1), m.group(2)) for m in attrPairRE.finditer(openingElement.group())) vorxml = oaixml[ openingElement.end(): re.search("]*>", oaixml).start()] nsPrefixes = oaiclient.guessPrefixesUsed(vorxml) nsPrefixes.add(resType.split(":")[0]) res = ResourceWrapper(xsi_type=resType)(**nonNSAttrs)[vorxml] oaicore._addPrefixDefs(res, nsPrefixes) return res class MainPage(web.ServiceBasedPage): # Note: this is also used as a base class for vorlanding's MainPage. name = "custom" ivoid = None @classmethod def isBrowseable(cls, service): return True def makeResponse(self, request, oaiRec): """outputs oaiRec instrumented with our stylesheet to request. This also makes sure our media type is text/xml so browsers actually apply the style sheet. """ request.setHeader("content-type", "text/xml") # we're managing our schema locations ourselves since we don't # actually parse the OAI xml. return ( b"\n" +mungeOAIXML(oaiRec).render(includeSchemaLocation=False)) def render_GET(self, request): if self.ivoid in [None, ""]: return web.ServiceBasedPage.render_GET(self, request) with base.getTableConn() as conn: res = list( conn.query("select oaixml from rr.oairecs where ivoid=%(ivoid)s", {"ivoid": self.ivoid})) if not res: raise svcs.UnknownURI("No resource known for %s"%self.ivoid) return self.makeResponse(request, res[0][0]) def getChild(self, name, request): self.ivoid = "/".join(request.popSegments(name)).lower() if self.ivoid and not self.ivoid.startswith("ivo://"): self.ivoid = "ivo://"+self.ivoid return self loader = formal.XMLString(r""" GAVO IVOID resolver: Pass an IVOID

GAVO IVOID resolver: Pass an IVOID

This service lets you resolve IVOA identifiers, i.e., URIs referencing Virtual Observatory resources (they have a URI scheme of ivo://) to the resource records. There you will find all kinds of metadata there, including access options (“capabilities”).

To do this resolution, take an IVOID and prepend it with https://dc.g-vo.org/I/.

For instance, to this service is registered as ivo://org.gavo.dc/rr/q/nmah. To see the registry record, you would paste https://dc.g-vo.org/I/ivo://org.gavo.dc/rr/q/nmah into your web browser's address line.