From 2938ec43fa0e6a09d0cf1a80778329f72fc7ca3c Mon Sep 17 00:00:00 2001
From: Brandon Croft <brandon.croft@gmail.com>
Date: Wed, 15 Dec 2021 10:02:48 -0700
Subject: [PATCH] [cloud] handle unreachable run tasks

---
 internal/cloud/backend_plan.go          |  3 ++-
 internal/cloud/backend_runTasks.go      | 36 +++++++++++++------------
 internal/cloud/backend_runTasks_test.go | 10 +++++++
 3 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/internal/cloud/backend_plan.go b/internal/cloud/backend_plan.go
index 2ec1439ea..0a7975d64 100644
--- a/internal/cloud/backend_plan.go
+++ b/internal/cloud/backend_plan.go
@@ -351,9 +351,10 @@ in order to capture the filesystem context the remote workspace expects:
 		}
 	}
 
-	// Await collective run tasks
+	// Await pre-apply run tasks
 	if len(r.TaskStage) > 0 {
 		context := NewIntegrationContext(stopCtx, cancelCtx, b, op, r)
+		// TODO: this only works while there is exactly 1 task stage
 		err = b.runTasks(context, context.BeginOutput("Run Tasks (pre-apply)"), r.TaskStage[0].ID)
 
 		if err != nil {
diff --git a/internal/cloud/backend_runTasks.go b/internal/cloud/backend_runTasks.go
index 8ef8679e4..ab00a6aac 100644
--- a/internal/cloud/backend_runTasks.go
+++ b/internal/cloud/backend_runTasks.go
@@ -9,6 +9,7 @@ import (
 )
 
 type taskResultSummary struct {
+	unreachable     bool
 	pending         int
 	failed          int
 	failedMandatory int
@@ -17,10 +18,14 @@ type taskResultSummary struct {
 
 type taskStageReadFunc func(b *Cloud, stopCtx context.Context) (*tfe.TaskStage, error)
 
-func summarizeTaskResults(taskResults []*tfe.TaskResult) taskResultSummary {
+func summarizeTaskResults(taskResults []*tfe.TaskResult) *taskResultSummary {
 	var pe, er, erm, pa int
 	for _, task := range taskResults {
-		if task.Status == "running" || task.Status == "pending" {
+		if task.Status == "unreachable" {
+			return &taskResultSummary{
+				unreachable: true,
+			}
+		} else if task.Status == "running" || task.Status == "pending" {
 			pe++
 		} else if task.Status == "passed" {
 			pa++
@@ -33,7 +38,8 @@ func summarizeTaskResults(taskResults []*tfe.TaskResult) taskResultSummary {
 		}
 	}
 
-	return taskResultSummary{
+	return &taskResultSummary{
+		unreachable:     false,
 		pending:         pe,
 		failed:          er,
 		failedMandatory: erm,
@@ -41,19 +47,7 @@ func summarizeTaskResults(taskResults []*tfe.TaskResult) taskResultSummary {
 	}
 }
 
-// elapsedMessageMax is 50 chars: the length of this message with 6 digits
-// 99 tasks still pending, 99 passed, 99 failed ...
-const elapsedMessageMax int = 50
-
 func (b *Cloud) runTasksWithTaskResults(context *IntegrationContext, output IntegrationOutputWriter, fetchTaskStage taskStageReadFunc) error {
-	// TODO: Do not fetch run tasks if there are no changes to infrastructure
-	// if !context.Run.HasChanges {
-	// 	output.Output("No Changes. Tasks will not run")
-	// 	output.End()
-
-	// 	return nil
-	// }
-
 	return context.Poll(func(i int) (bool, error) {
 		// TODO: get the stage that corresponds to an argument passed to this function
 		stage, err := fetchTaskStage(b, context.StopContext)
@@ -63,12 +57,20 @@ func (b *Cloud) runTasksWithTaskResults(context *IntegrationContext, output Inte
 		}
 
 		summary := summarizeTaskResults(stage.TaskResults)
+
+		if summary.unreachable {
+			output.Output("Skipping task results.")
+			output.End()
+			return false, nil
+		}
+
 		if summary.pending > 0 {
-			message := fmt.Sprintf("%d tasks still pending, %d passed, %d failed ... ", summary.pending, summary.passed, summary.failed)
+			pendingMessage := "%d tasks still pending, %d passed, %d failed ... "
+			message := fmt.Sprintf(pendingMessage, summary.pending, summary.passed, summary.failed)
 
 			if i%4 == 0 {
 				if i > 0 {
-					output.OutputElapsed(message, elapsedMessageMax)
+					output.OutputElapsed(message, len(pendingMessage)) // Up to 2 digits are allowed by the max message allocation
 				}
 			}
 			return true, nil
diff --git a/internal/cloud/backend_runTasks_test.go b/internal/cloud/backend_runTasks_test.go
index 9cb133cd5..d33220446 100644
--- a/internal/cloud/backend_runTasks_test.go
+++ b/internal/cloud/backend_runTasks_test.go
@@ -118,6 +118,16 @@ func TestCloud_runTasksWithTaskResults(t *testing.T) {
 			expectedOutputs: []string{"Failed (Advisory)", "Overall Result: Passed with advisory failure"},
 			isError:         false,
 		},
+		"unreachable": {
+			taskResults: []*tfe.TaskResult{
+				{ID: "1", TaskName: "Mandatory", Message: "", Status: "unreachable", WorkspaceTaskEnforcementLevel: "mandatory"},
+				{ID: "2", TaskName: "Advisory", Message: "", Status: "unreachable", WorkspaceTaskEnforcementLevel: "advisory"},
+			},
+			writer:          writer,
+			context:         integrationContext,
+			expectedOutputs: []string{"Skipping"},
+			isError:         false,
+		},
 	}
 
 	for caseName, c := range cases {