Having a hard time with provider for_each: An instance key can be specified only for a provider configuration that uses for_each.

[mardonner]

I'm on tofu 1.9.1 and no matter what I try i always get the error An instance key can be specified only for a provider configuration that uses for_each. Even though I create multiple provider config isntances.

This reduced example config will fail during tofu init:

provider config:

terraform {
  required_version = "~> 1.9.0"
  required_providers {
    postgresql = {
      source = "cyrilgdn/postgresql"
      version = "1.25.0"
    }
  }
}
provider "postgresql" {
  alias = "by_db"
  for_each = toset(["a","b","c"])
  host = "test.test"
  port  = 5432
  database = "test"
  username = "test"
  password  = each.key
  sslmode = "require"
  connect_timeout = 15
}

referencing the provider:

resource "postgresql_schema" "test" {
  for_each = toset(["a","b","c"])
  provider = postgres.by_db[each.key]
  name  = each.key
  owner = "test"
}

tf init output:

╷
│ Error: Invalid resource provider configuration
│ 
│   on test.tf line 3, in resource "postgresql_schema" "test":
│    3:   provider = postgres.by_db[each.key]
│ 
│ An instance key can be specified only for a provider configuration that
│ uses for_each.
╵

There must be something obvious I'm doing wrong here but I can't find the mistake even after staring at the documentation.

[yottta]

Hi, there is a typo in:

resource "postgresql_schema" "test" {
  for_each = toset(["a","b","c"])
  provider = postgres.by_db[each.key]
  name  = each.key
  owner = "test"
}

Replace
provider = postgres.by_db[each.key]
with
provider = postgresql.by_db[each.key]

[cam72cam]

Hmm, this check could be improved by seeing if the provider is even passed into this context. With this someone invalid check, it's skipping the later checks that would have made this issue more visible.

[cam72cam]

#2805

[mardonner]

Thanks for the fast reply. That was indeed the issue. Spelling mistakes seem to be my strongest enemy as of lately 😅