Dependencies
More often than not, Azure resources within a single deployment have dependencies on each other. For instance, our Function App depends on both Consumption Plan and Storage Account.
Parallel or sequential
By default, Azure deployment will try to deploy all resources in parallel to minimize the deployment time. However, you should avoid a possible situation when a dependent resource starts deploying before all required resources are ready.
Up until now, we were adding resources one-by-one and making frequent deployments, so we didn’t face any issues. However, if you try creating a new Resource Group and deploying the whole template at once, you might get some errors back.
Explicit dependencies
We can tell Azure about dependencies between resources by setting the dependsOn property. Add the following snippet to your Function App resource:
"dependsOn": [
"[variables('storageAccountName')]",
"[variables('planName')]"
],Now, if you create a blank Resource Group and rerun the deployment, Azure will first deploy a Storage Account and a Consumption Plan, wait for those to complete, and only then start the deployment of the Function App.
Implicit dependencies
Some template functions, e.g., reference and list*, create an implicit dependency between the resource in its argument and the resource where it’s used.
Since implicit dependencies aren’t very obvious and have some tricky boundary conditions, I recommend always to set an explicit dependency, even if an implicit function is used.
Checkpoint
Run the deployment one more time. You should get no errors, and the HTTP endpoint should still return a greeting.
If you have any difficulties, compare your code with this sample.