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| 1 | +################## |
| 2 | +# |
| 3 | +# This file is a drop-in to provide a helm provider. |
| 4 | +# |
| 5 | +# It depends on 2 standard Cloud Posse data source modules to be already |
| 6 | +# defined in the same component: |
| 7 | +# |
| 8 | +# 1. module.iam_roles to provide the AWS profile or Role ARN to use to access the cluster |
| 9 | +# 2. module.eks to provide the EKS cluster information |
| 10 | +# |
| 11 | +# All the following variables are just about configuring the Kubernetes provider |
| 12 | +# to be able to modify EKS cluster. The reason there are so many options is |
| 13 | +# because at various times, each one of them has had problems, so we give you a choice. |
| 14 | +# |
| 15 | +# The reason there are so many "enabled" inputs rather than automatically |
| 16 | +# detecting whether or not they are enabled based on the value of the input |
| 17 | +# is that any logic based on input values requires the values to be known during |
| 18 | +# the "plan" phase of Terraform, and often they are not, which causes problems. |
| 19 | +# |
| 20 | +variable "kubeconfig_file_enabled" { |
| 21 | + type = bool |
| 22 | + default = false |
| 23 | + description = "If `true`, configure the Kubernetes provider with `kubeconfig_file` and use that kubeconfig file for authenticating to the EKS cluster" |
| 24 | + nullable = false |
| 25 | +} |
| 26 | + |
| 27 | +variable "kubeconfig_file" { |
| 28 | + type = string |
| 29 | + default = "" |
| 30 | + description = "The Kubernetes provider `config_path` setting to use when `kubeconfig_file_enabled` is `true`" |
| 31 | + nullable = false |
| 32 | +} |
| 33 | + |
| 34 | +variable "kubeconfig_context" { |
| 35 | + type = string |
| 36 | + default = "" |
| 37 | + description = <<-EOT |
| 38 | + Context to choose from the Kubernetes config file. |
| 39 | + If supplied, `kubeconfig_context_format` will be ignored. |
| 40 | + EOT |
| 41 | + nullable = false |
| 42 | +} |
| 43 | + |
| 44 | +variable "kubeconfig_context_format" { |
| 45 | + type = string |
| 46 | + default = "" |
| 47 | + description = <<-EOT |
| 48 | + A format string to use for creating the `kubectl` context name when |
| 49 | + `kubeconfig_file_enabled` is `true` and `kubeconfig_context` is not supplied. |
| 50 | + Must include a single `%s` which will be replaced with the cluster name. |
| 51 | + EOT |
| 52 | + nullable = false |
| 53 | +} |
| 54 | + |
| 55 | +variable "kube_data_auth_enabled" { |
| 56 | + type = bool |
| 57 | + default = false |
| 58 | + description = <<-EOT |
| 59 | + If `true`, use an `aws_eks_cluster_auth` data source to authenticate to the EKS cluster. |
| 60 | + Disabled by `kubeconfig_file_enabled` or `kube_exec_auth_enabled`. |
| 61 | + EOT |
| 62 | + nullable = false |
| 63 | +} |
| 64 | + |
| 65 | +variable "kube_exec_auth_enabled" { |
| 66 | + type = bool |
| 67 | + default = true |
| 68 | + description = <<-EOT |
| 69 | + If `true`, use the Kubernetes provider `exec` feature to execute `aws eks get-token` to authenticate to the EKS cluster. |
| 70 | + Disabled by `kubeconfig_file_enabled`, overrides `kube_data_auth_enabled`. |
| 71 | + EOT |
| 72 | + nullable = false |
| 73 | +} |
| 74 | + |
| 75 | +variable "kube_exec_auth_role_arn" { |
| 76 | + type = string |
| 77 | + default = "" |
| 78 | + description = "The role ARN for `aws eks get-token` to use" |
| 79 | + nullable = false |
| 80 | +} |
| 81 | + |
| 82 | +variable "kube_exec_auth_role_arn_enabled" { |
| 83 | + type = bool |
| 84 | + default = true |
| 85 | + description = "If `true`, pass `kube_exec_auth_role_arn` as the role ARN to `aws eks get-token`" |
| 86 | + nullable = false |
| 87 | +} |
| 88 | + |
| 89 | +variable "kube_exec_auth_aws_profile" { |
| 90 | + type = string |
| 91 | + default = "" |
| 92 | + description = "The AWS config profile for `aws eks get-token` to use" |
| 93 | + nullable = false |
| 94 | +} |
| 95 | + |
| 96 | +variable "kube_exec_auth_aws_profile_enabled" { |
| 97 | + type = bool |
| 98 | + default = false |
| 99 | + description = "If `true`, pass `kube_exec_auth_aws_profile` as the `profile` to `aws eks get-token`" |
| 100 | + nullable = false |
| 101 | +} |
| 102 | + |
| 103 | +variable "kubeconfig_exec_auth_api_version" { |
| 104 | + type = string |
| 105 | + default = "client.authentication.k8s.io/v1beta1" |
| 106 | + description = "The Kubernetes API version of the credentials returned by the `exec` auth plugin" |
| 107 | + nullable = false |
| 108 | +} |
| 109 | + |
| 110 | +variable "helm_manifest_experiment_enabled" { |
| 111 | + type = bool |
| 112 | + default = false |
| 113 | + description = "Enable storing of the rendered manifest for helm_release so the full diff of what is changing can been seen in the plan" |
| 114 | + nullable = false |
| 115 | +} |
| 116 | + |
| 117 | +locals { |
| 118 | + kubeconfig_file_enabled = var.kubeconfig_file_enabled |
| 119 | + kubeconfig_file = local.kubeconfig_file_enabled ? var.kubeconfig_file : "" |
| 120 | + kubeconfig_context = !local.kubeconfig_file_enabled ? "" : ( |
| 121 | + length(var.kubeconfig_context) != 0 ? var.kubeconfig_context : ( |
| 122 | + length(var.kubeconfig_context_format) != 0 ? format(var.kubeconfig_context_format, local.eks_cluster_id) : "" |
| 123 | + ) |
| 124 | + ) |
| 125 | + |
| 126 | + kube_exec_auth_enabled = local.kubeconfig_file_enabled ? false : var.kube_exec_auth_enabled |
| 127 | + kube_data_auth_enabled = local.kube_exec_auth_enabled ? false : var.kube_data_auth_enabled |
| 128 | + |
| 129 | + # Eventually we might try to get this from an environment variable |
| 130 | + kubeconfig_exec_auth_api_version = var.kubeconfig_exec_auth_api_version |
| 131 | + |
| 132 | + exec_profile = local.kube_exec_auth_enabled && var.kube_exec_auth_aws_profile_enabled ? [ |
| 133 | + "--profile", var.kube_exec_auth_aws_profile |
| 134 | + ] : [] |
| 135 | + |
| 136 | + kube_exec_auth_role_arn = coalesce(var.kube_exec_auth_role_arn, module.iam_roles.terraform_role_arn) |
| 137 | + exec_role = local.kube_exec_auth_enabled && var.kube_exec_auth_role_arn_enabled ? [ |
| 138 | + "--role-arn", local.kube_exec_auth_role_arn |
| 139 | + ] : [] |
| 140 | + |
| 141 | + # Provide dummy configuration for the case where the EKS cluster is not available. |
| 142 | + certificate_authority_data = local.kubeconfig_file_enabled ? null : try(module.eks.outputs.eks_cluster_certificate_authority_data, null) |
| 143 | + cluster_ca_certificate = local.kubeconfig_file_enabled ? null : try(base64decode(local.certificate_authority_data), null) |
| 144 | + # Use coalesce+try to handle both the case where the output is missing and the case where it is empty. |
| 145 | + eks_cluster_id = coalesce(try(module.eks.outputs.eks_cluster_id, ""), "missing") |
| 146 | + eks_cluster_endpoint = local.kubeconfig_file_enabled ? null : try(module.eks.outputs.eks_cluster_endpoint, "") |
| 147 | +} |
| 148 | + |
| 149 | +data "aws_eks_cluster_auth" "eks" { |
| 150 | + count = local.kube_data_auth_enabled ? 1 : 0 |
| 151 | + name = local.eks_cluster_id |
| 152 | +} |
| 153 | + |
| 154 | +provider "helm" { |
| 155 | + kubernetes { |
| 156 | + host = local.eks_cluster_endpoint |
| 157 | + cluster_ca_certificate = local.cluster_ca_certificate |
| 158 | + token = local.kube_data_auth_enabled ? one(data.aws_eks_cluster_auth.eks[*].token) : null |
| 159 | + # It is too confusing to allow the Kubernetes provider to use environment variables to set authentication |
| 160 | + # in this module because we have so many options, so we override environment variables like `KUBE_CONFIG_PATH` |
| 161 | + # in all cases. People can still use environment variables by setting TF_VAR_kubeconfig_file. |
| 162 | + config_path = local.kubeconfig_file |
| 163 | + config_context = local.kubeconfig_context |
| 164 | + |
| 165 | + dynamic "exec" { |
| 166 | + for_each = local.kube_exec_auth_enabled && local.certificate_authority_data != null ? ["exec"] : [] |
| 167 | + content { |
| 168 | + api_version = local.kubeconfig_exec_auth_api_version |
| 169 | + command = "aws" |
| 170 | + args = concat(local.exec_profile, [ |
| 171 | + "eks", "get-token", "--cluster-name", local.eks_cluster_id |
| 172 | + ], local.exec_role) |
| 173 | + } |
| 174 | + } |
| 175 | + } |
| 176 | + experiments { |
| 177 | + manifest = var.helm_manifest_experiment_enabled && module.this.enabled |
| 178 | + } |
| 179 | +} |
| 180 | + |
| 181 | +provider "kubernetes" { |
| 182 | + host = local.eks_cluster_endpoint |
| 183 | + cluster_ca_certificate = local.cluster_ca_certificate |
| 184 | + token = local.kube_data_auth_enabled ? one(data.aws_eks_cluster_auth.eks[*].token) : null |
| 185 | + # It is too confusing to allow the Kubernetes provider to use environment variables to set authentication |
| 186 | + # in this module because we have so many options, so we override environment variables like `KUBE_CONFIG_PATH` |
| 187 | + # in all cases. People can still use environment variables by setting TF_VAR_kubeconfig_file. |
| 188 | + config_path = local.kubeconfig_file |
| 189 | + config_context = local.kubeconfig_context |
| 190 | + |
| 191 | + dynamic "exec" { |
| 192 | + for_each = local.kube_exec_auth_enabled && local.certificate_authority_data != null ? ["exec"] : [] |
| 193 | + content { |
| 194 | + api_version = local.kubeconfig_exec_auth_api_version |
| 195 | + command = "aws" |
| 196 | + args = concat(local.exec_profile, [ |
| 197 | + "eks", "get-token", "--cluster-name", local.eks_cluster_id |
| 198 | + ], local.exec_role) |
| 199 | + } |
| 200 | + } |
| 201 | +} |
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