feat: show an accurate description for Constructs in validation errors (#1110)

Until now, validation errors would only show the underlying base type of the
construct. Many Constructs share the same base type, which makes it hard to
tell them apart.

Now, each Construct implements a `describe()` method which returns a unique
description for the Construct instance. It consists of the Construct class
name and the logicalId of the instance.

Author: sorccu

packages/cli/src/constructs/alert-channel-subscription.ts

@@ -48,6 +48,10 @@ export class AlertChannelSubscription extends Construct {
     Session.registerConstruct(this)
   }
 
+  describe (): string {
+    return `AlertChannelSubscription:${this.logicalId}`
+  }
+
   synthesize () {
     return {
       alertChannelId: this.alertChannelId,

packages/cli/src/constructs/alert-channel.ts

@@ -77,6 +77,10 @@ export class AlertChannelRef extends Construct {
     Session.registerConstruct(this)
   }
 
+  describe (): string {
+    return `AlertChannelRef:${this.logicalId}`
+  }
+
   synthesize () {
     return null
   }

packages/cli/src/constructs/api-check.ts

@@ -231,6 +231,10 @@ export class ApiCheck extends RuntimeCheck {
     this.addPrivateLocationCheckAssignments()
   }
 
+  describe (): string {
+    return `ApiCheck:${this.logicalId}`
+  }
+
   async validate (diagnostics: Diagnostics): Promise<void> {
     if (this.setupScript) {
       if (!isEntrypoint(this.setupScript) && !isContent(this.setupScript)) {

packages/cli/src/constructs/browser-check.ts

@@ -102,6 +102,10 @@ export class BrowserCheck extends RuntimeCheck {
     this.addPrivateLocationCheckAssignments()
   }
 
+  describe (): string {
+    return `BrowserCheck:${this.logicalId}`
+  }
+
   protected configDefaultsGetter (props: CheckProps): ConfigDefaultsGetter {
     return makeConfigDefaultsGetter(
       props.group?.getBrowserCheckDefaults(),

packages/cli/src/constructs/check-group-ref.ts

@@ -14,6 +14,10 @@ export class CheckGroupRef extends Construct {
     Session.registerConstruct(this)
   }
 
+  describe (): string {
+    return `CheckGroupRef:${this.logicalId}`
+  }
+
   public getCheckDefaults (): CheckConfigDefaults {
     // The only value CheckGroup.getCheckDefaults() returns is frequency,
     // which exists purely for convenience, and only at CLI-level. It never

packages/cli/src/constructs/check-group-v1.ts

@@ -350,6 +350,10 @@ export class CheckGroupV1 extends Construct {
     this.__addPrivateLocationGroupAssignments()
   }
 
+  describe (): string {
+    return `CheckGroupV1:${this.logicalId}`
+  }
+
   protected async onBeforeValidate (diagnostics: Diagnostics): Promise<void> {
     diagnostics.add(new DeprecatedConstructDiagnostic(
       'CheckGroup',

packages/cli/src/constructs/check-group-v2.ts

@@ -146,6 +146,10 @@ export class CheckGroupV2 extends CheckGroupV1 {
     this.useGlobalAlertSettings = useGlobalAlertSettings
   }
 
+  describe (): string {
+    return `CheckGroupV2:${this.logicalId}`
+  }
+
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
   async onBeforeValidate (diagnostics: Diagnostics): Promise<void> {
     // No-op

packages/cli/src/constructs/construct-diagnostics.ts

@@ -89,7 +89,7 @@ export class ConstructDiagnostic extends Diagnostic {
 
   constructor (construct: Construct, underlying: Diagnostic) {
     super({
-      title: `[${construct.type}:${construct.logicalId}] ${underlying.title}`,
+      title: `[${construct.describe()}] ${underlying.title}`,
       message: underlying.message,
     })
 

packages/cli/src/constructs/construct.ts

@@ -72,6 +72,11 @@ export abstract class Construct implements Validate, Bundle {
     Session.validateCreateConstruct(this)
   }
 
+  /**
+   * @returns A unique description of the Construct instance.
+   */
+  abstract describe (): string
+
   /**
    * Creates a reference to this construct that can be used in other constructs.
    * 

packages/cli/src/constructs/dashboard.ts

@@ -273,6 +273,10 @@ export class Dashboard extends Construct {
     Session.registerConstruct(this)
   }
 
+  describe (): string {
+    return `Dashboard:${this.logicalId}`
+  }
+
   async validate (diagnostics: Diagnostics): Promise<void> {
     if (!this.customUrl && !this.customDomain) {
       diagnostics.add(new InvalidPropertyValueDiagnostic(