_BuildDoc.parse_backend() return wrong results for MyVariant build docs

[erikyao]

Description

Involved class: from biothings.hub.dataindex.indexer import _BuildDoc

A sample input document from myvariant_hubdb.src_build is as below:

{
    _id : "yy_test_superhot_hg19_20220628_maatbmxp"
    target_backend : "mongo"
    target_name : "yy_test_superhot_hg19_20220628_maatbmxp"
    backend_url : "yy_test_superhot_hg19_20220628_maatbmxp"

    # other fields omitted
}

With the above argument, _BuildDoc.parse_backend() will return the following backend:

_BuildBackend(host=..., port=..., dbs="myvariant", col="yy_test_superhot_hg19_20220628_maatbmxp")

while the correct backend should be:

_BuildBackend(host=..., port=..., dbs="myvariant_hubdb", col="src_build")

Hypothesis

1. The logic of _BuildDoc.parse_backend() is wrong, or
2. target_name and backend_url are not correctly written for MyVariant src_build docs, and thus cause _BuildDoc.parse_backend() to output wrong backends.
   • If true, we must clarify the correct values for these two fields.

Workaround

Use from biothings.utils.hub_db import get_src_build to locate the myvariant_hubdb.src_build collection for now, at least in MyVariant hub.