depends_on cannot be used in a module

[chrisrlong]

Hi there,

Terraform Version

0.8.0 rc1+

Affected Resource(s)

module

Terraform Configuration Files

module "legacy_site" {
  source = "../../../../../modules/site"
  name = "foo-site"
  health_check_target = "TCP:443"
  azs = "${var.azs}"
  instance_count = "${var.instance_count}"
  vpc = "apps"
  region = "${var.region}"
  environment = "${var.environment}"
  run_list = "hs_site_foo"

  #rds_complete = "${module.rds.db_instance_id}"
  #elasticache_cache_complete = "${module.elasticache_cache.elasticache_id}"
  #elasticache_sessions_complete = "${module.elasticache_sessions.elasticache_id}"

  depends_on = [
  "module.rds",
  "module.elasticache_sessions"
  ]

}

Debug Output

Error loading Terraform: module root: module legacy_site: depends_on is not a valid parameter
module root: module legacy_site: depends_on is not a valid parameter

Expected Behavior

I am trying to use the new depends_on instead of the above outputs, so I create and provision my app once I know database and caches are built.

Actual Behavior

Nothing as terraform errors out as above.

Steps to Reproduce

1. terraform apply

References

depends_on can reference modules. This allows a resource or output to depend on everything within a module. (#10076)

[stack72]

Hi @chrisrlong

This is very strange - we introduced depends_on for modules in 0.8.0-beta2

can you run terraform version and post the output here for me?

Paul

[chrisrlong]

Hi @stack72,

I have complied master from version b15b8bd (Terraform v0.8.0-dev (b15b8bd+CHANGES)), which should include beta2 features. (I did this to get 10337 and 10338 fixes)

It seems it would work if you set a resource to depend on a module, but you cannot set a module to depend_on another module......

Thanks for the great tool btw ;)

Chris

[stack72]

Hi @chrisrlong

thanks for getting back to me - you are indeed correct - modules cannot (currently) depend_on other modules but can depend on a resource only

Will change the tag on this from bug to enhancement :)

Keep an eye out for it soon ™️

Thanks

Paul

[mitchellh]

Retagging as enhancement, since this isn't broken functionality, its functionality that doesn't exist yet. :)

[sheerun]

My use case: the slave virtual machine depends on master virtual machine to exist

[shantanugadgil]

I am seeing the same error:
module root: module example: depends_on is not a valid parameter

My Terraform version is:
Terraform v0.8.2

My use case is that I want a module to depend on a resource.

[arehmandev]

Error loading Terraform: module root: module etcdbastion: depends_on is not a valid parameter.
^ Seeing it here too

[cemo]

@mitchellh I believe this one can solve unnested modules problem too. There were some issues regarding this #10883 before. This solution would be intuitive and address these issues.

[vladimir-kozyrev]

Waiting for this feature to be added 👍

[prog893]

+1