Implement multi-assertion check

.github/workflows/CICD.yml

@@ -82,6 +82,50 @@ jobs:
         uses: Invicton-Labs/terraform-module-testing/[email protected]
         with:
           tf_path: tests/pass-condition-message-delayed
+
+      - name: Initialize - Pass - Multi
+        id: init-pass-multi
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi
+      - name: Run Tests - Pass - Multi
+        id: tests-pass-multi
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi
+
+      - name: Initialize - Pass - Multi - Condition Delayed
+        id: init-pass-multi-condition-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi-condition-delayed
+      - name: Run Tests - Pass - Multi - Condition Delayed
+        id: tests-pass-multi-condition-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi-condition-delayed
+
+      - name: Initialize - Pass - Multi - Message Delayed
+        id: init-pass-multi-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi-message-delayed
+      - name: Run Tests - Pass - Multi - Message Delayed
+        id: tests-pass-multi-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi-message-delayed
+
+      - name: Initialize - Pass - Multi - Condition and Message Delayed
+        id: init-pass-multi-condition-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi-condition-message-delayed
+      - name: Run Tests - Pass - Multi - Condition and Message Delayed
+        id: tests-pass-multi-condition-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/pass-multi-condition-message-delayed
 
       - name: Initialize - Fail
         id: init-fail
@@ -143,6 +187,42 @@ jobs:
           tf_path: tests/fail-condition-message-delayed
           stderr_contains: sample error
 
+      - name: Initialize - Fail - Multi - Condition Delayed
+        id: init-fail-multi-condition-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/fail-multi-condition-delayed
+      - name: Run Tests - Fail - Multi - Condition Delayed
+        id: tests-fail-multi-condition-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/fail-multi-condition-delayed
+          stderr_contains: sample error
+
+      - name: Initialize - Fail - Multi - Message Delayed
+        id: init-fail-multi-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/fail-multi-message-delayed
+      - name: Run Tests - Fail - Multi - Message Delayed
+        id: tests-fail-multi-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/fail-multi-message-delayed
+          stderr_contains: sample error
+
+      - name: Initialize - Fail - Multi - Condition and Message Delayed
+        id: init-fail-multi-condition-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/fail-multi-condition-message-delayed
+      - name: Run Tests - Fail - Multi - Condition and Message Delayed
+        id: tests-fail-multi-condition-message-delayed
+        uses: Invicton-Labs/terraform-module-testing/[email protected]
+        with:
+          tf_path: tests/fail-multi-condition-message-delayed
+          stderr_contains: sample error
+
   # This job just waits for all other jobs to pass. We have it here
   # so our branch protection rule can reference a single job, instead
   # of needing to list every matrix value of every job above.

outputs.tf

@@ -1,3 +1,6 @@
+//==================================================
+//     Outputs that match the input variables
+//==================================================
 output "error_message" {
   description = "The value of the `error_message` input variable."
   value       = var.error_message
@@ -8,6 +11,14 @@ output "condition" {
   value       = var.condition
 }
 
+output "assertions" {
+  description = "The value of the `assertions` input variable."
+  value       = var.assertions
+}
+
+//==================================================
+//       Outputs generated by this module
+//==================================================
 output "checked" {
   description = "Whether the condition has been checked (used for assertion dependencies)."
   value       = var.condition == true ? true : true

tests/fail-multi-condition-delayed/main.tf

@@ -0,0 +1,13 @@
+module "fail_multi_condition_delayed" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = uuid() == ""
+      error_message = "sample error"
+    },
+    {
+      condition     = uuid() == ""
+      error_message = "sample error"
+    }
+  ]
+}

tests/fail-multi-condition-message-delayed/main.tf

@@ -0,0 +1,13 @@
+module "fail_multi_condition_message_delayed" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = uuid() == ""
+      error_message = "sample error: ${uuid()}"
+    },
+    {
+      condition     = uuid() == ""
+      error_message = "sample error: ${uuid()}"
+    }
+  ]
+}

tests/fail-multi-message-delayed/main.tf

@@ -0,0 +1,13 @@
+module "fail_multi_message_delayed" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = false
+      error_message = "sample error: ${uuid()}"
+    },
+    {
+      condition     = false
+      error_message = "sample error: ${uuid()}"
+    }
+  ]
+}

tests/fail-multi/main.tf

@@ -0,0 +1,13 @@
+module "fail_multi" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = false
+      error_message = "sample error"
+    },
+    {
+      condition     = false
+      error_message = "sample error"
+    }
+  ]
+}

tests/pass-multi-condition-delayed/main.tf

@@ -0,0 +1,13 @@
+module "pass_multi_condition_delayed" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = uuid() != ""
+      error_message = "sample error"
+    },
+    {
+      condition     = uuid() != ""
+      error_message = "sample error"
+    }
+  ]
+}

tests/pass-multi-condition-message-delayed/main.tf

@@ -0,0 +1,13 @@
+module "pass_multi_condition_message_delayed" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = uuid() != ""
+      error_message = "sample error: ${uuid()}"
+    },
+    {
+      condition     = uuid() != ""
+      error_message = "sample error: ${uuid()}"
+    }
+  ]
+}

tests/pass-multi-message-delayed/main.tf

@@ -0,0 +1,13 @@
+module "pass_multi_message_delayed" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = true
+      error_message = "sample error: ${uuid()}"
+    },
+    {
+      condition     = true
+      error_message = "sample error: ${uuid()}"
+    }
+  ]
+}

tests/pass-multi/main.tf

@@ -0,0 +1,13 @@
+module "pass_multi" {
+  source = "../../"
+  assertions = [
+    {
+      condition     = true
+      error_message = "Not needed!"
+    },
+    {
+      condition     = true
+      error_message = "Not needed!"
+    }
+  ]
+}

variables.tf

@@ -1,18 +1,75 @@
 variable "error_message" {
   description = "The error message to display if the condition evaluates to `false`."
   type        = string
-  nullable    = false
+  nullable    = true
+  default     = null
 }
 
 variable "condition" {
   description = "The condition to ensure is `true`."
   type        = bool
+  nullable    = true
+  default     = null
   validation {
-    // We have to use var.error_message != null to force the evaluation to wait
+    // We have to use var.error_message == "" to force the evaluation to wait
     // until var.error_message is known. Otherwise, it can fail during the validation
     // phase but won't output the proper error message.
     // https://github.com/hashicorp/terraform/issues/35397
-    condition     = var.error_message == "" ? var.condition : var.condition
-    error_message = var.error_message
+    condition = var.condition == null ? true : (var.error_message == null ? true : (var.error_message == "" ? var.condition : var.condition))
+    error_message = var.condition == null ? "" : (
+      var.condition ? "" : (
+        var.error_message == null ? "" : "ASSERTION FAILURE: ${var.error_message}"
+      )
+    )
+  }
+}
+
+variable "assertions" {
+  description = "A list of conditions and error message pairs to check. This is for use when you want to make multiple assertions with a single instance of this module."
+  type = list(object({
+    condition     = bool
+    error_message = string
+  }))
+  default  = null
+  nullable = true
+
+  // Verify that either the single assertion variables are used, or this variable is used. Not both.
+  validation {
+    // Ternaries allow lazy evaluation, which reduces the chance that a value
+    // not known at plan time will force this validation to wait for apply time.
+    condition = (
+      var.condition == null ? (
+        var.error_message == null ? var.assertions != null : false
+      ) : false
+      ) ? true : (
+      var.condition != null ? (
+        var.error_message != null ? var.assertions == null : false
+      ) : false
+    )
+    error_message = "Either the `condition` and `error_message` variables must be provided and the `assertions` variable must be `null`, or the `assertions` variable must be provided and the `condition` and `error_message` variables must be `null`. To check a single assertion, use `condition` and `error_message`; to check multiple assertions, use `assertions`."
+  }
+
+  // Check that either there is no assertions list, or if there is,
+  // none of the conditions in it are false.
+  validation {
+    // We pass this validation if `condition` or `error_message` are not null,
+    // so it throws the validation error about multiple vars being provided instead
+    // of actually checking the assertions in this variable.
+    condition = var.condition != null ? true : (
+      var.error_message != null ? true : (
+        var.assertions == null ? true : (
+          length([
+            for v in var.assertions :
+            false
+            if !v.condition
+          ]) == 0
+        )
+      )
+    )
+    error_message = var.assertions == null ? "" : join("\n\n", [
+      for v in var.assertions :
+      "ASSERTION FAILURE: ${v.error_message}"
+      if !v.condition
+    ])
   }
 }