Union() issues with 0.25.3

[cedricbraekevelt]

Bicep version
0.25.3

Describe the bug
We use the Union() function a lot to merge a resource specific naming object with a general naming for all resources. Since 0.25.3 this gives us an error for all properties that aren't optional as you can see below.

To Reproduce

@export()
type naming = {
  @description('Override the abbreviation of this resource with this parameter')
  abbreviation: string?
  @description('The resource environment (for example: dev, tst, acc, prd)')
  environment: string?
  @description('The resource location (for example: weu, we, westeurope)')
  location: string?
  @description('The name of the customer')
  customer: string?
  @description('The delimiter between resources (default: -)')
  delimiter: string?
  @description('The order of the array defines the order of elements in the naming scheme')
  nameFormat: ('abbreviation' | 'function' | 'environment' | 'location' | 'customer' | 'param1' | 'param2' | 'param3')[]?
  @description('Extra parameter self defined')
  param1: string?
  @description('Extra parameter self defined')
  param2: string?
  @description('Extra parameter self defined')
  param3: string?
  @description('Full name of the resource overwrites the combinated name')
  overrideName: string?
  @description('Function of the resource [can be app, db, security,...]')
  function: string
  @description('Suffix for the resource, if empty non will be appended, otherwise will be added to the end [can be index, ...]')
  suffix: string?
}

param defaultNaming naming

param resourceNaming naming

param test naming = union(defaultNaming, resourceNaming)

The error that we receive in this case is:

The specified "object" declaration is missing the following required properties: "function".bicep(BCP035)

As you can see function is the only required property in this user defined object, and is the one causing trouble. However, if I require other properties, they also add to the list.

[jeskew]

As a quick workaround on this if you need to unblock a build, the any() function will get you past the BCP035 diagnostic:

param test naming = any(union(defaultNaming, resourceNaming))

Working on fixing type inference for the union function, but it's a bit more complex than anticipated.

[pie-r]

Same here, we fixed it using the previous version 0.24.x to avoid this not backward compatible change.

@vlahane Can you share the other issue that we have? If is not related we should open a different github issue

[vlahane]

seems like similar issue but without union as well as with union function.
resouces.bicep(7,5) : Error BCP035: The specified "object" declaration is missing the following required properties: "objectId".

Below are the simplified tests for existing bicep our code.

Test-1

bicep build result

0.25.3 (8627085) : Passed ✅
0.24.24 (5646341) : Passed ✅

//resource.bicep
param location string
param accessPolicies object[]

resource akv 'Microsoft.KeyVault/vaults@2023-07-01' = {
  location: location
  name: 'myakv'
  properties: {
    sku: {
      family: 'A'
      name: 'standard'
    }
    tenantId: 'xxxxxxxx-86xx-xxxx-91xx-xx7cd011dxxx'
    accessPolicies: accessPolicies
  }
}

Test-2

bicep build result

0.25.3 (8627085) : Failed ❌
0.24.24 (5646341) : Passed ✅

//dependencies.bicep
type accessPoliciesObj = {
  objectId: string
  permissions: object?
}

param location string
param accessPolicies accessPoliciesObj[]

resource akv 'Microsoft.KeyVault/vaults@2023-07-01' = {
  location: location
  name: 'myakv'
  properties: {
    sku: {
      family: 'A'
      name: 'standard'
    }
    tenantId: 'xxxxxxxx-86xx-xxxx-91xx-xx7cd011dxxx'
    accessPolicies: accessPolicies
  }
}

//resource.bicep
//hint: looks like not able to typecast to accessPoliciesObj type in new bicep version i.e. 0.25.3
param accessPolicies object[] 


module test 'dependencies.bicep' = {
  name: 'test-module'
  params: {
    accessPolicies: accessPolicies
    location: 'eastus'
  }
}

error in Test-2 and we have been using the same code in our project

resouces.bicep(7,5) : Error BCP035: The specified "object" declaration is missing the following required properties: "objectId".

[slavizh]

+1 this is a big bug.

[miqm]

please make sure it'll work with map:

map(items(_object), x=> union({ id: x.key }, x.value))

[vlahane]

shouldn't we add support for explicit type casting as well in future? something like below?

import { accessPoliciesObjType } from './types.bicep'
param myPolicies object[]

module test 'dependencies.bicep' = {
  name: 'test-module'
  params: {
    accessPolicies: accessPoliciesObjType(myPolicies) //explicit type casting
    location: 'eastus'
  }
}

[timkatje]

Our Azure DevOps Pipeline started popping this error today after no changes to the bicep files. We figured there'd been an update that broke existing behavior.

For us, we simply read in a list of tags on the containing resource group and union them with a locally defined list of tags. Previously, this code worked:
tags: union(resourceGroup().tags, tags)

All the mention of "types" in this issue clued me in on what to look for. Knowing that there's a ToObject function available to us, I decided to test appending that to the existing code, and now our main.bicep lints passes linting:
tags: union(resourceGroup().tags, tags).ToObject

Interestingly, we use this exact tag union code three different times in our main.bicep, but only the first two uses errored out. The two erroring modules are two version newer than the non-failing module, so I expect that upon review, we'll find some defect in those modules that this error has brought to our attention.

TLDR: Using the ToObject() function may resolve this while awaiting a new version of bicep.

[anthony-c-martin]

@timkatje we've just released v0.23.53 which should have the fix. Could you verify which version of Bicep you are using?