feat(bedrockconstruct): added support for IAM existingRole (#454)

* feat(constructprop): added existinRole to bedrock agent and kb

* feat(constructprop): added existinRole to bedrock agent and kb

* chore: self mutation

Signed-off-by: github-actions <[email protected]>

* chore: self mutation

Signed-off-by: github-actions <[email protected]>

---------

Signed-off-by: github-actions <[email protected]>
Signed-off-by: Dinesh Sajwan <[email protected]>
Co-authored-by: Dinesh Sajwan <[email protected]>
Co-authored-by: github-actions <[email protected]>
Co-authored-by: Alain Krok <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: 5 people

apidocs/interfaces/bedrock.AgentProps.md

@@ -15,6 +15,7 @@ Properties for a Bedrock Agent.
 - [description](bedrock.AgentProps.md#description)
 - [enableUserInput](bedrock.AgentProps.md#enableuserinput)
 - [encryptionKey](bedrock.AgentProps.md#encryptionkey)
+- [existingRole](bedrock.AgentProps.md#existingrole)
 - [foundationModel](bedrock.AgentProps.md#foundationmodel)
 - [idleSessionTTL](bedrock.AgentProps.md#idlesessionttl)
 - [instruction](bedrock.AgentProps.md#instruction)
@@ -98,6 +99,15 @@ KMS encryption key to use for the agent.
 
 ___
 
+### existingRole
+
+• `Optional` `Readonly` **existingRole**: `Role`
+
+The existing IAM Role for the agent with a trust policy that
+allows the Bedrock service to assume the role.
+
+___
+
 ### foundationModel
 
 • `Readonly` **foundationModel**: [`BedrockFoundationModel`](../classes/bedrock.BedrockFoundationModel.md)

apidocs/interfaces/bedrock.KnowledgeBaseProps.md

@@ -12,6 +12,7 @@ Properties for a knowledge base
 
 - [description](bedrock.KnowledgeBaseProps.md#description)
 - [embeddingsModel](bedrock.KnowledgeBaseProps.md#embeddingsmodel)
+- [existingRole](bedrock.KnowledgeBaseProps.md#existingrole)
 - [indexName](bedrock.KnowledgeBaseProps.md#indexname)
 - [instruction](bedrock.KnowledgeBaseProps.md#instruction)
 - [knowledgeBaseState](bedrock.KnowledgeBaseProps.md#knowledgebasestate)
@@ -45,6 +46,18 @@ The embeddings model for the knowledge base
 
 ___
 
+### existingRole
+
+• `Optional` `Readonly` **existingRole**: `Role`
+
+Existing IAM role with a policy statement
+granting permission to invoke the specific embeddings model.
+Any entity (e.g., an AWS service or application) that assumes
+this role will be able to invoke or use the
+specified embeddings model within the Bedrock service.
+
+___
+
 ### indexName
 
 • `Optional` `Readonly` **indexName**: `string`

src/cdk-lib/bedrock/agent.ts

@@ -212,6 +212,13 @@ export interface AgentProps {
    * @default - A name is automatically generated.
    */
   readonly name?: string;
+
+  /**
+   * The existing IAM Role for the agent with a trust policy that
+   * allows the Bedrock service to assume the role.
+   */
+  readonly existingRole?: iam.Role;
+
   /**
    * A narrative instruction to provide the agent as context.
    */
@@ -376,44 +383,47 @@ export class Agent extends Construct {
       'bedrock-agent',
       { maxLength: 32, lower: true, separator: '-' });
 
-    this.role = new iam.Role(this, 'Role', {
-      assumedBy: new iam.ServicePrincipal('bedrock.amazonaws.com'),
-      roleName: generatePhysicalNameV2(
-        this,
-        'AmazonBedrockExecutionRoleForAgents_',
-        { maxLength: 64, lower: false }),
-    });
-
-    this.role.assumeRolePolicy!.addStatements(
-      new iam.PolicyStatement({
-        actions: ['sts:AssumeRole'],
-        principals: [new iam.ServicePrincipal('bedrock.amazonaws.com')],
-        conditions: {
-          StringEquals: {
-            'aws:SourceAccount': cdk.Stack.of(this).account,
-          },
-          ArnLike: {
-            'aws:SourceArn': cdk.Stack.of(this).formatArn({
-              service: 'bedrock',
-              resource: 'agent',
-              resourceName: '*',
-              arnFormat: cdk.ArnFormat.SLASH_RESOURCE_NAME,
-            }),
-          },
-        },
-      }),
-    );
+    if (props.existingRole) {
+      this.role = props.existingRole;
+    } else {
+      this.role = new iam.Role(this, 'Role', {
+        assumedBy: new iam.ServicePrincipal('bedrock.amazonaws.com'),
+        roleName: generatePhysicalNameV2(
+          this,
+          'AmazonBedrockExecutionRoleForAgents_',
+          { maxLength: 64, lower: false }),
+      });
 
-    new iam.Policy(this, 'AgentFMPolicy', {
-      roles: [this.role],
-      statements: [
+      this.role.assumeRolePolicy!.addStatements(
         new iam.PolicyStatement({
-          actions: ['bedrock:InvokeModel'],
-          resources: [props.foundationModel.asArn(this)],
+          actions: ['sts:AssumeRole'],
+          principals: [new iam.ServicePrincipal('bedrock.amazonaws.com')],
+          conditions: {
+            StringEquals: {
+              'aws:SourceAccount': cdk.Stack.of(this).account,
+            },
+            ArnLike: {
+              'aws:SourceArn': cdk.Stack.of(this).formatArn({
+                service: 'bedrock',
+                resource: 'agent',
+                resourceName: '*',
+                arnFormat: cdk.ArnFormat.SLASH_RESOURCE_NAME,
+              }),
+            },
+          },
         }),
-      ],
-    });
-
+      );
+
+      new iam.Policy(this, 'AgentFMPolicy', {
+        roles: [this.role],
+        statements: [
+          new iam.PolicyStatement({
+            actions: ['bedrock:InvokeModel'],
+            resources: [props.foundationModel.asArn(this)],
+          }),
+        ],
+      });
+    }
 
     const agent = new bedrock.CfnAgent(this, 'Agent', {
 

src/cdk-lib/bedrock/knowledge-base.ts

@@ -111,6 +111,15 @@ export interface KnowledgeBaseProps {
    */
   readonly description?: string;
 
+  /**
+   * Existing IAM role with a policy statement
+   * granting permission to invoke the specific embeddings model.
+   * Any entity (e.g., an AWS service or application) that assumes
+   * this role will be able to invoke or use the
+   * specified embeddings model within the Bedrock service.
+   */
+  readonly existingRole?: iam.Role;
+
   /**
    * A narrative description of the knowledge base.
    *
@@ -261,39 +270,43 @@ export class KnowledgeBase extends Construct {
       'KB',
       { maxLength: 32 });
 
-    const roleName = generatePhysicalNameV2(
-      this,
-      'AmazonBedrockExecutionRoleForKnowledgeBase',
-      { maxLength: 64 });
-    this.role = new iam.Role(this, 'Role', {
-      roleName: roleName,
-      assumedBy: new iam.ServicePrincipal('bedrock.amazonaws.com'),
-    });
-    this.role.assumeRolePolicy!.addStatements(
-      new iam.PolicyStatement({
-        actions: ['sts:AssumeRole'],
-        principals: [new iam.ServicePrincipal('bedrock.amazonaws.com')],
-        conditions: {
-          StringEquals: {
-            'aws:SourceAccount': cdk.Stack.of(this).account,
-          },
-          ArnLike: {
-            'aws:SourceArn': cdk.Stack.of(this).formatArn({
-              service: 'bedrock',
-              resource: 'knowledge-base',
-              resourceName: '*',
-              arnFormat: cdk.ArnFormat.SLASH_RESOURCE_NAME,
-            }),
-          },
-        },
-      }),
-    );
 
-    this.role.addToPolicy(new iam.PolicyStatement({
-      actions: ['bedrock:InvokeModel'],
-      resources: [embeddingsModel.asArn(this)],
-    }));
+    if (props.existingRole) {
+      this.role = props.existingRole;
+    } else {
+      const roleName = generatePhysicalNameV2(
+        this,
+        'AmazonBedrockExecutionRoleForKnowledgeBase',
+        { maxLength: 64 });
+      this.role = new iam.Role(this, 'Role', {
+        roleName: roleName,
+        assumedBy: new iam.ServicePrincipal('bedrock.amazonaws.com'),
+      });
+      this.role.assumeRolePolicy!.addStatements(
+        new iam.PolicyStatement({
+          actions: ['sts:AssumeRole'],
+          principals: [new iam.ServicePrincipal('bedrock.amazonaws.com')],
+          conditions: {
+            StringEquals: {
+              'aws:SourceAccount': cdk.Stack.of(this).account,
+            },
+            ArnLike: {
+              'aws:SourceArn': cdk.Stack.of(this).formatArn({
+                service: 'bedrock',
+                resource: 'knowledge-base',
+                resourceName: '*',
+                arnFormat: cdk.ArnFormat.SLASH_RESOURCE_NAME,
+              }),
+            },
+          },
+        }),
+      );
 
+      this.role.addToPolicy(new iam.PolicyStatement({
+        actions: ['bedrock:InvokeModel'],
+        resources: [embeddingsModel.asArn(this)],
+      }));
+    }
     /**
      * Create the vector store if the vector store was provided by the user.
      * Otherwise check againts all possible vector datastores.