[sdk-gen] Use specialized missing required property exception (#1228)

# Description

This PR adds a new custom exception `MissingRequiredPropertyException`
to the main Java SDK. Then SDK-gen uses this type and throws it as an
error when an input property is required but isn't specified. This fixes
#1199 where previously the users would receive a `NullPointerException`
instead.

Due to using Go templates and conditionals as follows:
```
{{ if $setter.IsRequired }} 
...
{{ end }}
```
The generated code emits an empty line when `IsRequired` is `false`
which is why you will see the new line diffs in the commits of this PR

## Checklist

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unchecked. -->
- [x] I have added tests that prove my fix is effective or that my
feature works
<!--- 
User-facing changes require a CHANGELOG entry.
-->
- [x] I have updated the
[CHANGELOG-PENDING](https://github.com/pulumi/pulumi/blob/master/CHANGELOG_PENDING.md)
file with my change
<!--
If the change(s) in this PR is a modification of an existing call to the
Pulumi Service,
then the service should honor older versions of the CLI where this
change would not exist.
You must then bump the API version in
/pkg/backend/httpstate/client/api.go, as well as add
it to the service.
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- [ ] Yes, there are changes in this PR that warrants bumping the Pulumi
Service API version
<!-- @pulumi employees: If yes, you must submit corresponding changes in
the service repo. -->

CHANGELOG_PENDING.md

@@ -1,9 +1,5 @@
 ### Improvements
 
-- Adds `MissingRequiredPropertyException` to the main java SDK to be used later in the generated provider SDKs.
+- Generated SDKs use specialized `MissingRequiredPropertyException` rather than throwing `NullPointerException` when a required input property is missing.
 
-### Bug Fixes
-
-- Fixes `builder()` implementation for result types where the identifier of the local variable defined for the result type collides with one of the fields of the result type.
-- Adds `options.encoding = "UTF-8"` to the `compileJava` options so that it can handle non-ASCII characters in the source code, especially in the documentation comments of fields.
-- Fixes MockMonitor reporting DeletedWith wasn't supported
+### Bug Fixes

pkg/codegen/java/gen.go

@@ -491,6 +491,7 @@ func (pt *plainType) genInputType(ctx *classFileContext) error {
 
 	// Determine property types
 	propTypes := make([]TypeShape, len(pt.properties))
+	anyPropertyRequired := false
 	for i, prop := range pt.properties {
 		requireInitializers := !pt.args || isInputType(prop.Type)
 
@@ -503,6 +504,14 @@ func (pt *plainType) genInputType(ctx *classFileContext) error {
 			false,               // outer optional
 			false,               // inputless overload
 		)
+
+		if prop.IsRequired() {
+			anyPropertyRequired = true
+		}
+	}
+
+	if anyPropertyRequired {
+		ctx.imports.Ref(names.PulumiMissingRequiredPropertyException)
 	}
 
 	w := ctx.writer
@@ -599,6 +608,15 @@ func (pt *plainType) genInputType(ctx *classFileContext) error {
 	for propIndex, prop := range pt.properties {
 		propType := propTypes[propIndex]
 		fieldName := names.Ident(pt.mod.propertyName(prop)).AsProperty().Field()
+
+		if prop.IsRequired() && prop.DefaultValue == nil && prop.ConstValue == nil {
+			fprintf(w, "            if ($.%s == null) {\n", fieldName)
+			fprintf(w, "                throw new %s(\"%s\", \"%s\");\n",
+				ctx.ref(names.PulumiMissingRequiredPropertyException), pt.name, fieldName)
+			fprintf(w, "            }\n")
+			continue
+		}
+
 		propRef := fmt.Sprintf("$.%s", fieldName)
 		propInit, err := dg.defaultValueExpr(
 			fmt.Sprintf("property of class %s", pt.name),
@@ -704,6 +722,7 @@ func (pt *plainType) genOutputType(ctx *classFileContext) error {
 	fprintf(w, "@%s\n", ctx.ref(names.CustomType))
 	fprintf(w, "public final class %s {\n", pt.name)
 
+	anyPropertyRequired := false
 	// Generate each output field.
 	for _, prop := range props {
 		fieldName := names.Ident(pt.mod.propertyName(prop))
@@ -721,7 +740,15 @@ func (pt *plainType) genOutputType(ctx *classFileContext) error {
 			isGetter: true,
 		})
 		fprintf(w, "    private %s %s;\n", fieldType.ToCode(ctx.imports), fieldName)
+		if prop.IsRequired() {
+			anyPropertyRequired = true
+		}
+	}
+
+	if anyPropertyRequired {
+		ctx.imports.Ref(names.PulumiMissingRequiredPropertyException)
 	}
+
 	if len(props) > 0 {
 		fprintf(w, "\n")
 	}
@@ -810,12 +837,6 @@ func (pt *plainType) genOutputType(ctx *classFileContext) error {
 		})
 
 		setterName := propertyName.AsProperty().Setter()
-		assignment := func(propertyName names.Ident) string {
-			if prop.IsRequired() {
-				return fmt.Sprintf("this.%s = %s.requireNonNull(%s)", propertyName, ctx.ref(names.Objects), propertyName)
-			}
-			return fmt.Sprintf("this.%s = %s", propertyName, propertyName)
-		}
 
 		// add setter
 		var setterAnnotation string
@@ -828,7 +849,8 @@ func (pt *plainType) genOutputType(ctx *classFileContext) error {
 			SetterName:   setterName,
 			PropertyType: propertyType.ToCode(ctx.imports),
 			PropertyName: propertyName.String(),
-			Assignment:   assignment(propertyName),
+			Assignment:   fmt.Sprintf("this.%s = %s", propertyName, propertyName),
+			IsRequired:   prop.IsRequired(),
 			ListType:     propertyType.ListType(ctx),
 			Annotations:  []string{setterAnnotation},
 		})

pkg/codegen/java/names/known.go

@@ -8,6 +8,10 @@ var Optional = JavaUtil.Dot("Optional")
 
 var Pulumi = Ident("com").FQN().Dot("pulumi")
 
+var PulumiExceptions = Pulumi.Dot("exceptions")
+
+var PulumiMissingRequiredPropertyException = PulumiExceptions.Dot("MissingRequiredPropertyException")
+
 var PulumiCore = Pulumi.Dot("core")
 
 var PulumiAsset = Pulumi.Dot("asset")

pkg/codegen/java/templates.go

@@ -136,6 +136,7 @@ type builderSetterTemplateContext struct {
 	PropertyType string
 	PropertyName string
 	Assignment   string
+	IsRequired   bool
 	ListType     string
 	Annotations  []string
 }
@@ -173,6 +174,9 @@ const builderTemplateText = `{{ .Indent }}public static {{ .Name }} builder() {
 {{ $.Indent }}    {{ $annotation }}
 {{- end }}
 {{ $.Indent }}    public {{ $.Name }} {{ $setter.SetterName }}({{ $setter.PropertyType }} {{ $setter.PropertyName }}) {
+{{ if $setter.IsRequired }}{{ $.Indent }}        if ({{ $setter.PropertyName }} == null) {
+{{ $.Indent }}          throw new MissingRequiredPropertyException("{{ $.ResultType }}", "{{ $setter.PropertyName }}");
+{{ $.Indent }}        }{{ end }}
 {{ $.Indent }}        {{ $setter.Assignment }};
 {{ $.Indent }}        return this;
 {{ $.Indent }}    }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecActivationsArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Integer;
 import java.lang.String;
 import java.util.List;
@@ -236,9 +237,15 @@ public Builder version(Integer version) {
         }
 
         public AppSecActivationsArgs build() {
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.notificationEmails = Objects.requireNonNull($.notificationEmails, "expected parameter 'notificationEmails' to be non-null");
-            $.version = Objects.requireNonNull($.version, "expected parameter 'version' to be non-null");
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecActivationsArgs", "configId");
+            }
+            if ($.notificationEmails == null) {
+                throw new MissingRequiredPropertyException("AppSecActivationsArgs", "notificationEmails");
+            }
+            if ($.version == null) {
+                throw new MissingRequiredPropertyException("AppSecActivationsArgs", "version");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecAdvancedSettingsEvasivePathMatchArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Boolean;
 import java.lang.Integer;
 import java.lang.String;
@@ -152,8 +153,12 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecAdvancedSettingsEvasivePathMatchArgs build() {
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.enablePathMatch = Objects.requireNonNull($.enablePathMatch, "expected parameter 'enablePathMatch' to be non-null");
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsEvasivePathMatchArgs", "configId");
+            }
+            if ($.enablePathMatch == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsEvasivePathMatchArgs", "enablePathMatch");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecAdvancedSettingsLoggingArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Integer;
 import java.lang.String;
 import java.util.Objects;
@@ -151,8 +152,12 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecAdvancedSettingsLoggingArgs build() {
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.logging = Objects.requireNonNull($.logging, "expected parameter 'logging' to be non-null");
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsLoggingArgs", "configId");
+            }
+            if ($.logging == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsLoggingArgs", "logging");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecAdvancedSettingsPragmaHeaderArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Integer;
 import java.lang.String;
 import java.util.Objects;
@@ -151,8 +152,12 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecAdvancedSettingsPragmaHeaderArgs build() {
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.pragmaHeader = Objects.requireNonNull($.pragmaHeader, "expected parameter 'pragmaHeader' to be non-null");
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPragmaHeaderArgs", "configId");
+            }
+            if ($.pragmaHeader == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPragmaHeaderArgs", "pragmaHeader");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecAdvancedSettingsPrefetchArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Boolean;
 import java.lang.Integer;
 import java.lang.String;
@@ -235,11 +236,21 @@ public Builder extensions(String... extensions) {
         }
 
         public AppSecAdvancedSettingsPrefetchArgs build() {
-            $.allExtensions = Objects.requireNonNull($.allExtensions, "expected parameter 'allExtensions' to be non-null");
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.enableAppLayer = Objects.requireNonNull($.enableAppLayer, "expected parameter 'enableAppLayer' to be non-null");
-            $.enableRateControls = Objects.requireNonNull($.enableRateControls, "expected parameter 'enableRateControls' to be non-null");
-            $.extensions = Objects.requireNonNull($.extensions, "expected parameter 'extensions' to be non-null");
+            if ($.allExtensions == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPrefetchArgs", "allExtensions");
+            }
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPrefetchArgs", "configId");
+            }
+            if ($.enableAppLayer == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPrefetchArgs", "enableAppLayer");
+            }
+            if ($.enableRateControls == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPrefetchArgs", "enableRateControls");
+            }
+            if ($.extensions == null) {
+                throw new MissingRequiredPropertyException("AppSecAdvancedSettingsPrefetchArgs", "extensions");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecApiConstraintsProtectionArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Boolean;
 import java.lang.Integer;
 import java.lang.String;
@@ -150,9 +151,15 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecApiConstraintsProtectionArgs build() {
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.enabled = Objects.requireNonNull($.enabled, "expected parameter 'enabled' to be non-null");
-            $.securityPolicyId = Objects.requireNonNull($.securityPolicyId, "expected parameter 'securityPolicyId' to be non-null");
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecApiConstraintsProtectionArgs", "configId");
+            }
+            if ($.enabled == null) {
+                throw new MissingRequiredPropertyException("AppSecApiConstraintsProtectionArgs", "enabled");
+            }
+            if ($.securityPolicyId == null) {
+                throw new MissingRequiredPropertyException("AppSecApiConstraintsProtectionArgs", "securityPolicyId");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecApiRequestConstraintsArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Integer;
 import java.lang.String;
 import java.util.Objects;
@@ -188,9 +189,15 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecApiRequestConstraintsArgs build() {
-            $.action = Objects.requireNonNull($.action, "expected parameter 'action' to be non-null");
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.securityPolicyId = Objects.requireNonNull($.securityPolicyId, "expected parameter 'securityPolicyId' to be non-null");
+            if ($.action == null) {
+                throw new MissingRequiredPropertyException("AppSecApiRequestConstraintsArgs", "action");
+            }
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecApiRequestConstraintsArgs", "configId");
+            }
+            if ($.securityPolicyId == null) {
+                throw new MissingRequiredPropertyException("AppSecApiRequestConstraintsArgs", "securityPolicyId");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecAttackGroupArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Integer;
 import java.lang.String;
 import java.util.Objects;
@@ -225,10 +226,18 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecAttackGroupArgs build() {
-            $.attackGroup = Objects.requireNonNull($.attackGroup, "expected parameter 'attackGroup' to be non-null");
-            $.attackGroupAction = Objects.requireNonNull($.attackGroupAction, "expected parameter 'attackGroupAction' to be non-null");
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.securityPolicyId = Objects.requireNonNull($.securityPolicyId, "expected parameter 'securityPolicyId' to be non-null");
+            if ($.attackGroup == null) {
+                throw new MissingRequiredPropertyException("AppSecAttackGroupArgs", "attackGroup");
+            }
+            if ($.attackGroupAction == null) {
+                throw new MissingRequiredPropertyException("AppSecAttackGroupArgs", "attackGroupAction");
+            }
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecAttackGroupArgs", "configId");
+            }
+            if ($.securityPolicyId == null) {
+                throw new MissingRequiredPropertyException("AppSecAttackGroupArgs", "securityPolicyId");
+            }
             return $;
         }
     }

pkg/codegen/testing/test/testdata/akamai/java/src/main/java/com/pulumi/akamai/AppSecByPassNetworkListArgs.java

@@ -5,6 +5,7 @@
 
 import com.pulumi.core.Output;
 import com.pulumi.core.annotations.Import;
+import com.pulumi.exceptions.MissingRequiredPropertyException;
 import java.lang.Integer;
 import java.lang.String;
 import java.util.List;
@@ -160,9 +161,15 @@ public Builder securityPolicyId(String securityPolicyId) {
         }
 
         public AppSecByPassNetworkListArgs build() {
-            $.bypassNetworkLists = Objects.requireNonNull($.bypassNetworkLists, "expected parameter 'bypassNetworkLists' to be non-null");
-            $.configId = Objects.requireNonNull($.configId, "expected parameter 'configId' to be non-null");
-            $.securityPolicyId = Objects.requireNonNull($.securityPolicyId, "expected parameter 'securityPolicyId' to be non-null");
+            if ($.bypassNetworkLists == null) {
+                throw new MissingRequiredPropertyException("AppSecByPassNetworkListArgs", "bypassNetworkLists");
+            }
+            if ($.configId == null) {
+                throw new MissingRequiredPropertyException("AppSecByPassNetworkListArgs", "configId");
+            }
+            if ($.securityPolicyId == null) {
+                throw new MissingRequiredPropertyException("AppSecByPassNetworkListArgs", "securityPolicyId");
+            }
             return $;
         }
     }