Before reading this document about how to use configuration overlays with Run services make sure you are familiar with the concept of configuration overlays and how they work. Working with configuration overlays with Run services is very similar to working with them in the Nhost stack. There are a few differences though:
  1. Commands to work with the configuration are located under nhost run config-..., for instance:
nhost run config-show --config ../mysvc/nhost-run-service.toml
name = 'bun-gen'

[image]
image = 'nhost/bun-generator:0.0.3'

[[environment]]
name = 'PEXELS_API_KEY'
value = 'asdasdasd'

[[ports]]
port = 5000
type = 'http'
publish = true

[resources]
replicas = 1

[resources.compute]
cpu = 62
memory = 128
  1. Unless explicitly indicated by the help of the command, overlays are never applied automatically, a flag needs to be used to apply the overlay:
nhost run config-show --config ../mysvc/nhost-run-service.toml --overlay-name mysvc
name = 'mysvc'

[image]
image = 'nhost/bun-generator:0.0.3'

[[environment]]
name = 'PEXELS_API_KEY'
value = 'asdasdasd'

[[environment]]
name = 'ENVIRONMENT'
value = 'development'

[resources]
replicas = 1

[resources.compute]
cpu = 62
memory = 128
  1. A notable exception of the point above is nhost run config-deploy --service-id SERVICE_ID, which, as indicated by the help, will apply automatically the overlay with name SERVICE_ID if it exists:
$ nhost run config-deploy --help
NAME:
   nhost run config-deploy - Deploy service configuration

USAGE:
   nhost run config-deploy [command options] [arguments...]

OPTIONS:
   --config value      Service configuration file (default: "nhost-run-service.toml") [$NHOST_RUN_SERVICE_CONFIG]
   --service-id value  Service ID to update. Applies overlay of the same name [$NHOST_RUN_SERVICE_ID]
   --help, -h          show help
  1. Overlays will be located under the same base path as the specified configuration file, under nhost/overlays and prefixed with run-. If you are using the command nhost run config-show --config ../mysvc/nhost-run-service.toml --overlay-name mysvc to edit overlays this is handled by you and you don’t need to be worried about. For instance:
$ nhost run config-show --config ../mysvc/nhost-run-service.toml --overlay-name mysvc
(output omitted for brevity)
$ find ../mysvc
find ../mysvc
../mysvc
../mysvc/nhost
../mysvc/nhost/overlays
../mysvc/nhost/overlays/run-mysvc.json
../mysvc/nhost/overlays/run-70dca23e-aeed-4351-b37d-9a4a6f17147f.json
../mysvc/nhost-run-service.toml
  1. When running nhost up --run-service ... no overlay will be applied automatically. If you want to apply an overlay you will need to specify the name of the overlay name to apply by prefixing the path with :overlay_name, for instance: nhost up --run-service ../mysvc/nhost-run-service.toml:mysvc