5:44 p.m.
Hello Everybody,
I've been working on a PR for the upcoming Hawkular Metrics release that will remove
the tenant id from the end-point URLs. The tenant id will be moved to either a header
parameter or a query parameter. The query parameter is in place for cases (such as curl)
where setting a header is not possible, difficult, or inconvenient.
Here is an example of the change:
Existing URL:
/{tenantId}/gauge/{metricId}/data
New URL:
/gauge/{metricId}/data
Tenant id set via:
1) header - tenantId
2) query parameter - tenantId
There are two exceptions to this rule, /tenants and /db/{tenantid}/series. The /tenants
end-point will be changed into something different in the upcoming releases since it is
mostly a management type API that does not belong in the same place with the regular
metrics endpoint. And /db/{tenantid}/series end-point is needed in this exact format for
compatibility with Influxdb compatible services.
Now, to the merits of this change. The tenant id is volatile, can change any time, and
changes to it should be expected; but the rest of the URL is fixed. The second issue is
that the tenant id is a security concern. So we were limited in design choices since a
security concern was leaking as part of the URL.
So removing the tenant id from the URL will give us permanent & consistent addresses
for resources (metrics and metric data points). And we will gain a lot of flexibility on
the security side. In the future, users could authenticate with a user/pass combo and the
backend would transform that into a tenant id to be used on the request. If the same user
later decides to use a tenant id to pass along the request, the URL of the resources would
not change. Another expectation is that tenant id is not sufficient, it is typically a
combo of id + secret; so we would have resorted to a header or query param for the second
piece of information (the secret).
This change will give us the flexibility to adjust the security model (the meaning of
tenant ids and ways to validate them) without compromising the URL structure. This will
help Hawkular Metrics as it gets integrated into more and more projects and products.
Here are the links to the JIRA and the PR for this change:
https://github.com/hawkular/hawkular-metrics/pull/202
https://issues.jboss.org/browse/HWKMETRICS-68
Thank you,
Stefan Negrea
Software Engineer