For web based XMPP clients it is not possible to execute DNS SRV requests to find address of XMPP server hosting for particular domain. To solve this the DNS Web Service module was created.
It handles incoming HTTP GET request and using Host
HTTP header executes DNS requests as specified in XEP-0156: Discovering Alternative XMPP Connection Methods.
Results are returned in XML or JSON as specified in the XEP mentioned before.
By default it is deployed at dns-webservice
and path for XML response is /dns-webservice/.well-known/host-meta
and for JSON is /dns-webservice/-known/host-meta.json
.