YakDriver

fatal error: concurrent map writes

goroutine 18527 [running]:
github.com/hashicorp/terraform-plugin-log/tflog.SetField.func1(...)
	/Volumes/develop/go/pkg/mod/github.com/hashicorp/terraform-plugin-log@v0.7.0/internal/logging/options.go:212
github.com/hashicorp/terraform-plugin-log/tflog.SetField({0xf042c40, 0xc0155e8d50}, {0xdbfb1dd, 0xd}, {0xb38bfe0?, 0xc0155ec0c0})
	/Volumes/develop/go/pkg/mod/github.com/hashicorp/terraform-plugin-log@v0.7.0/tflog/provider.go:18 +0x111
github.com/hashicorp/aws-sdk-go-base/v2/awsv1shim/v2.setAWSFields({0xf042c40?, 0xc015353ec0?}, 0xc00aa44000)
	/Volumes/develop/go/pkg/mod/github.com/hashicorp/aws-sdk-go-base/v2/awsv1shim/v2@v2.0.0-beta.23/logger.go:41 +0xec
github.com/hashicorp/aws-sdk-go-base/v2/awsv1shim/v2.logRequest(0xc00aa44000)

YakDriver

provider "aws" {}

locals {
  // cluster_name is a local to avoid the cyclical dependency:
  // cluster -> capacity provider -> asg -> launch template -> user data -> cluster.
  cluster_name = random_pet.name.id
}

data "aws_availability_zones" "current" {
  state = "available"

YakDriver

In Terraform provider development, if you were going to automate assigning characteristics of schema elements:

Check where element appears:

i = input (i.e., CreateObjectInput)
u = update (i.e., UpdateObjectInput)
o = output (i.e., DescribeObjectOutput)

This chart tells you when you need computed and forcenew.

YakDriver

func compareStringSlices(a []string, b []string) bool {
	if len(a) != len(b) {
		return false
	}
	sort.Strings(a)
	sort.Strings(b)
	for i := range b {
		if a[i] != b[i] {
			return false
		}

YakDriver

TypeSet vs. TypeList for Arguments and Attributes

General rule:

1. Use TypeSet when collection elements should be unique and order doesn't matter
2. Use TypeList otherwise

Special considerations:

1. If the argument needs to be optional and computed, only TypeList is supported (probably)
2. For configuration blocks where there can be only one, use TypeList MaxItems 1 to simplify things in the code/testing

YakDriver

1. Best is the enemy of good
2. The purpose of the provider is not to clean up the API
3. Even when the API seems wrong, follow it. It might actually be right and, if not, you can pass the blame.

YakDriver

history | awk '{print $2 " " $3}' | sort | uniq -c | sort -nr

YakDriver

Assumptions:
 - Terraform 0.12 tool has already been run
 - Variables fields are in the order: type, description, default (if any)
 
---------------------------------------------
BOOL
Transform 0.11 string booleans to native bool
---------------------------------------------
Find:(type\s+=\s*)string(\n\s+description.*\n\s+default\s+=\s+)"(false|true)"
Replace:$1bool$2$3

YakDriver

$ terraform apply

An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # aws_s3_bucket.encrypted will be created
  + resource "aws_s3_bucket" "encrypted" {

YakDriver

2019/05/24 17:44:02 [INFO] Terraform version: 0.12.0  
2019/05/24 17:44:02 [INFO] Go runtime version: go1.12.4
2019/05/24 17:44:02 [INFO] CLI args: []string{"/usr/local/bin/terraform", "apply"}
2019/05/24 17:44:02 [DEBUG] Attempting to open CLI config file: /Users/maviemarcos/.terraformrc
2019/05/24 17:44:02 [DEBUG] File doesn't exist, but doesn't need to. Ignoring.
2019/05/24 17:44:02 [INFO] CLI command args: []string{"apply"}
2019/05/24 17:44:02 [TRACE] Meta.Backend: no config given or present on disk, so returning nil config
2019/05/24 17:44:02 [TRACE] Meta.Backend: backend has not previously been initialized in this working directory
2019/05/24 17:44:02 [DEBUG] New state was assigned lineage "0eb1377e-4a69-a17b-5ddf-f4d25de5d570"
2019/05/24 17:44:02 [TRACE] Meta.Backend: using default local state only (no backend configuration, and no existing initialized backend)