Add docs for external-push scaler #193
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ahmelsayed
requested review from
jeffhollan,
tomkerkhove and
zroubalik
as code owners
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Yes, I'll put something together for that |
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@ahmelsayed any updated on the guidance doc pls? |
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Bump @ahmelsayed |
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Sorry about the delay, I'll get it done this week. |
Signed-off-by: Ahmed ElSayed <ahmels@microsoft.com>
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@tomkerkhove I added this guide. I tried to add a tabs shortcode like this one but using aplinejs instead of jquery, but after few hours I couldn't get it to work, so I just repurposed the component for FAQ. If someone knows alpinejs and hugo better than me, it would be nice to have the different languages in tabs rather than collapsible components, I think https://deploy-preview-193--keda.netlify.app/docs/2.0/concepts/external-scalers/ |
Signed-off-by: Ahmed ElSayed <ahmels@microsoft.com>
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| {{< collapsible "Golang" >}} | ||
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| Full implementation can be found here: https://github.com/ahmelsayed/external-scaler-samples |
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Can we donate this to kedacore?
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yes, was just preparing the repo. Will move it there.
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Thanks and also for the repo, very useful to have a reference as well!
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| The `Scaler` interface defines 4 methods: | ||
| - `GetMetrics` and `GetMetricsSpecForScaling` that are used to build the HPA definition for that particular scaler. |
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What should we expect here? It's not fully clear to me.
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There is a bit more details about them in the "Implementing" sections
GetMetricSpecreturns the target value for the HPA definition for the scaler. This scaler will define a static target of 10, but the threshold value is often specified in the metadata for other scalers.
GetMetricsreturns the value of the metric refered to fromGetMetricSpec, in this example it'searthquakeThreshold. Refer to the HPA docs for how HPA calculatesreplicaCountbased on metric value and target value.
It's easier to explain with an example, but I can expand the description there a bit. how about
GetMetricSpecreturns the target value for the HPA definition for the scaler. For more details refer to ImplementingGetMetricSpec
GetMetricsreturns the value of the metric refered to fromGetMetricSpec. For more details refer to ImplementingGetMetrics
?
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It helps a lot, thanks!
Examples are always welcome but not a must!
| scalerAddress: external-scaler-service:8080 | ||
| tlsCertFile: /path/to/tls/cert.pem # optional | ||
| ``` | ||
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I would add a link here maybe on how to write an external push scaler (concepts)?
Same goes for the external scaler.
Co-authored-by: Tom Kerkhove <kerkhove.tom@gmail.com>
Co-authored-by: Tom Kerkhove <kerkhove.tom@gmail.com>
Co-authored-by: Tom Kerkhove <kerkhove.tom@gmail.com>
Co-authored-by: Tom Kerkhove <kerkhove.tom@gmail.com>
Co-authored-by: Tom Kerkhove <kerkhove.tom@gmail.com>
Signed-off-by: Ahmed ElSayed <ahmels@microsoft.com>
Signed-off-by: Ahmed ElSayed <ahmels@microsoft.com>
Co-authored-by: Tom Kerkhove <kerkhove.tom@gmail.com>
Signed-off-by: Ahmed ElSayed <ahmels@microsoft.com>
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I'll open other PRs for porting the guide to 1.5 and 1.4 |
Signed-off-by: Ahmed ElSayed ahmels@microsoft.com