Locust: Support for tests that use multiple hosts

Created on 8 May 2014 · 6Comments · Source: locustio/locust

Our system runs two different hostnames (one for web, one for api requests), and it's not clear to me how to write a locust that would handle this. The --host option being passed to locust only allows passing one hostname (and assumes that the host resolves to the IP in question -- in a testing setup, the Host: header in the request to the web server might not resolve, as in testing during a build).

Suggestions?

Thanks,
Jeff

Source

jpotter

Most helpful comment

You _can_ actually make requests to different hosts, simply by specifying a full URL, however the hostname will not appear in the statistics entry, so requests to different hosts, but with the same path, will appear as a single stats entry:

self.client.get("/some/path")
self.client.get("http://other.host/some/path")

If you want them to be separate stats entries, you could override the entry name using the name parameter:

self.client.get("http://other.host/some/path", name="http://other.host/some/path")

If you could live with that, you could then specify a second host using an environment variable. Perhaps something like this:

import os

from locust import HttpLocust
from locust.clients import HttpSession

class MultipleHostsLocust(HttpLocust):
    abstract = True

    def __init__(self, *args, **kwargs):
        super(MultipleHostsLocust, self).__init__(*args, **kwargs)
        self.api_client = HttpSession(base_url=os.environ["API_HOST"])

heyman on 9 May 2014

👍22 😄1

All 6 comments

self.client.get("/some/path")
self.client.get("http://other.host/some/path")

If you want them to be separate stats entries, you could override the entry name using the name parameter:

self.client.get("http://other.host/some/path", name="http://other.host/some/path")

If you could live with that, you could then specify a second host using an environment variable. Perhaps something like this:

import os

from locust import HttpLocust
from locust.clients import HttpSession

class MultipleHostsLocust(HttpLocust):
    abstract = True

    def __init__(self, *args, **kwargs):
        super(MultipleHostsLocust, self).__init__(*args, **kwargs)
        self.api_client = HttpSession(base_url=os.environ["API_HOST"])

heyman on 9 May 2014

👍22 😄1

Hi Jonatan,

Thanks! I was able to get this working this way, and it makes sense. Locust looks like a really great tool for running these sorts of tests, and looking forward to getting it used as part of our production system!

best,
Jeff

jpotter on 10 May 2014

Glad to hear that :)!

You could also expand on my suggestion above, to make the api_client automatically set the name parameter, by subclassing the HttpSession class.

heyman on 11 May 2014

This also solved my problem. It would however be quite nice if I could leave "host" as blank totally. For cases where I write tests that always pass a full URL.