feat: enable $docref based on the compiled IGs (#83)

src/app.ts

@@ -22,6 +22,7 @@ import { applicationErrorMapper, httpErrorHandler, unknownErrorHandler } from '.
 import ExportRoute from './router/routes/exportRoute';
 import WellKnownUriRouteRoute from './router/routes/wellKnownUriRoute';
 import { FHIRStructureDefinitionRegistry } from './registry';
+import { initializeOperationRegistry } from './operationDefinitions';
 
 const configVersionSupported: ConfigVersion = 1;
 
@@ -38,6 +39,7 @@ export function generateServerlessRouter(
     const serverUrl: string = fhirConfig.server.url;
     let hasCORSEnabled: boolean = false;
     const registry = new FHIRStructureDefinitionRegistry(compiledImplementationGuides);
+    const operationRegistry = initializeOperationRegistry(configHandler);
 
     const app = express();
     app.use(express.urlencoded({ extended: true }));
@@ -70,7 +72,9 @@ export function generateServerlessRouter(
     // AuthZ
     app.use(async (req: express.Request, res: express.Response, next: express.NextFunction) => {
         try {
-            const requestInformation = getRequestInformation(req.method, req.path);
+            const requestInformation =
+                operationRegistry.getOperation(req.method, req.path)?.requestInformation ??
+                getRequestInformation(req.method, req.path);
             // Clean auth header (remove 'Bearer ')
             req.headers.authorization = cleanAuthHeader(req.headers.authorization);
             res.locals.userIdentity = await fhirConfig.auth.authorization.verifyAccessToken({
@@ -93,6 +97,11 @@ export function generateServerlessRouter(
         app.use('/', exportRoute.router);
     }
 
+    // Operations defined by OperationDefinition resources
+    operationRegistry.getAllRouters().forEach(router => {
+        app.use('/', router);
+    });
+
     // Special Resources
     if (fhirConfig.profile.resources) {
         Object.entries(fhirConfig.profile.resources).forEach(async resourceEntry => {

src/configHandler.ts

@@ -4,6 +4,7 @@
  */
 
 import { FhirConfig, FhirVersion, TypeOperation } from 'fhir-works-on-aws-interface';
+import ResourceHandler from './router/handlers/resourceHandler';
 
 export default class ConfigHandler {
     readonly config: FhirConfig;
@@ -66,4 +67,42 @@ export default class ConfigHandler {
 
         return resources;
     }
+
+    /**
+     * Get a `ResourceHandler` for a given `resourceType`. The `ResourceHandler` uses the most specific dependencies available in `FhirConfig`:
+     * 1. Use the dependencies specific to the given `resourceType` if they are defined.
+     * 2. Otherwise use the dependencies for `genericResource` if the given `resourceType` is a valid `genericResource`.
+     * 3. Otherwise return undefined.
+     */
+    getResourceHandler(resourceType: string): ResourceHandler | undefined {
+        if (this.config.profile.resources?.[resourceType]) {
+            const { persistence, typeSearch, typeHistory } = this.config.profile.resources[resourceType];
+            return new ResourceHandler(
+                persistence,
+                typeSearch,
+                typeHistory,
+                this.config.auth.authorization,
+                this.config.server.url,
+                this.config.validators,
+            );
+        }
+
+        if (
+            this.getGenericResources(this.config.profile.fhirVersion).includes(resourceType) &&
+            this.config.profile.genericResource
+        ) {
+            const { persistence, typeSearch, typeHistory } = this.config.profile.genericResource;
+
+            return new ResourceHandler(
+                persistence,
+                typeSearch,
+                typeHistory,
+                this.config.auth.authorization,
+                this.config.server.url,
+                this.config.validators,
+            );
+        }
+
+        return undefined;
+    }
 }

src/implementationGuides/index.test.ts

@@ -3,12 +3,12 @@
  *  SPDX-License-Identifier: Apache-2.0
  */
 
-import { StructureDefinitionImplementationGuides } from './index';
+import { RoutingImplementationGuides } from './index';
 
-describe('StructureDefinitionImplementationGuides', () => {
+describe('RoutingImplementationGuides', () => {
     describe(`compile`, async () => {
-        test(`valid StructureDefinition`, async () => {
-            const compiled = new StructureDefinitionImplementationGuides().compile([
+        test(`valid input`, async () => {
+            const compiled = new RoutingImplementationGuides().compile([
                 {
                     resourceType: 'StructureDefinition',
                     id: 'CARIN-BB-Organization',
@@ -28,24 +28,49 @@ describe('StructureDefinitionImplementationGuides', () => {
                     baseDefinition: 'http://hl7.org/fhir/us/core/StructureDefinition/us-core-organization',
                     derivation: 'constraint',
                 },
+                {
+                    resourceType: 'OperationDefinition',
+                    id: 'docref',
+                    url: 'http://hl7.org/fhir/us/core/OperationDefinition/docref',
+                    version: '3.1.1',
+                    name: 'USCoreFetchDocumentReferences',
+                    title: 'US Core Fetch DocumentReferences',
+                    status: 'active',
+                    kind: 'operation',
+                    date: '2019-05-21',
+                    publisher: 'US Core Project',
+                    description:
+                        'This operation is used to return all the references to documents related to a patient...',
+                    code: 'docref',
+                    system: false,
+                    type: true,
+                    instance: false,
+                    parameter: [],
+                },
             ]);
 
             await expect(compiled).resolves.toMatchInlineSnapshot(`
-                Array [
-                  Object {
-                    "baseDefinition": "http://hl7.org/fhir/us/core/StructureDefinition/us-core-organization",
-                    "description": "This profile builds on the USCoreOrganization Profile. It includes additional constraints relevant for the use cases addressed by this IG.",
-                    "name": "CARINBBOrganization",
-                    "resourceType": "StructureDefinition",
-                    "type": "Organization",
-                    "url": "http://hl7.org/fhir/us/carin/StructureDefinition/carin-bb-organization",
-                  },
-                ]
-            `);
+                        Array [
+                          Object {
+                            "baseDefinition": "http://hl7.org/fhir/us/core/StructureDefinition/us-core-organization",
+                            "description": "This profile builds on the USCoreOrganization Profile. It includes additional constraints relevant for the use cases addressed by this IG.",
+                            "name": "CARINBBOrganization",
+                            "resourceType": "StructureDefinition",
+                            "type": "Organization",
+                            "url": "http://hl7.org/fhir/us/carin/StructureDefinition/carin-bb-organization",
+                          },
+                          Object {
+                            "description": "This operation is used to return all the references to documents related to a patient...",
+                            "name": "USCoreFetchDocumentReferences",
+                            "resourceType": "OperationDefinition",
+                            "url": "http://hl7.org/fhir/us/core/OperationDefinition/docref",
+                          },
+                        ]
+                    `);
         });
 
-        test(`invalid StructureDefinition`, async () => {
-            const compiled = new StructureDefinitionImplementationGuides().compile([
+        test(`invalid input`, async () => {
+            const compiled = new RoutingImplementationGuides().compile([
                 {
                     foo: 'bar',
                 },

src/implementationGuides/index.ts

@@ -18,34 +18,65 @@ export type FhirStructureDefinition = {
     type: string;
 };
 
+/**
+ * Based on the FHIR OperationDefinition. This type only includes the fields that are required for the compile process.
+ * See: https://www.hl7.org/fhir/operationdefinition.html
+ */
+export type FhirOperationDefinition = {
+    resourceType: 'OperationDefinition';
+    url: string;
+    name: string;
+    description: string;
+};
+
 /**
  * This class compiles StructuredDefinitions from IG packages
  */
-export class StructureDefinitionImplementationGuides implements ImplementationGuides {
+export class RoutingImplementationGuides implements ImplementationGuides {
     /**
      * Compiles the contents of an Implementation Guide into an internal representation used to build the Capability Statement
      *
      * @param resources - an array of FHIR resources. See: https://www.hl7.org/fhir/profiling.html
      */
     // eslint-disable-next-line class-methods-use-this
     async compile(resources: any[]): Promise<any> {
-        const validStructureDefinitions: FhirStructureDefinition[] = [];
+        const validDefinitions: (FhirStructureDefinition | FhirOperationDefinition)[] = [];
         resources.forEach(s => {
-            if (StructureDefinitionImplementationGuides.isFhirStructureDefinition(s)) {
-                validStructureDefinitions.push(s);
+            if (
+                RoutingImplementationGuides.isFhirStructureDefinition(s) ||
+                RoutingImplementationGuides.isFhirOperationDefinition(s)
+            ) {
+                validDefinitions.push(s);
             } else {
-                throw new Error(`The following input is not a StructureDefinition: ${s.type} ${s.name}`);
+                throw new Error(
+                    `The following input is not a StructureDefinition nor a OperationDefinition: ${s.type} ${s.name}`,
+                );
             }
         });
 
-        return validStructureDefinitions.map((structureDefinition: any) => ({
-            name: structureDefinition.name,
-            url: structureDefinition.url,
-            type: structureDefinition.type,
-            resourceType: structureDefinition.resourceType,
-            description: structureDefinition.description,
-            baseDefinition: structureDefinition.baseDefinition,
-        }));
+        return validDefinitions.map(fhirDefinition => {
+            switch (fhirDefinition.resourceType) {
+                case 'StructureDefinition':
+                    return {
+                        name: fhirDefinition.name,
+                        url: fhirDefinition.url,
+                        type: fhirDefinition.type,
+                        resourceType: fhirDefinition.resourceType,
+                        description: fhirDefinition.description,
+                        baseDefinition: fhirDefinition.baseDefinition,
+                    };
+                case 'OperationDefinition':
+                    return {
+                        name: fhirDefinition.name,
+                        url: fhirDefinition.url,
+                        resourceType: fhirDefinition.resourceType,
+                        description: fhirDefinition.description,
+                    };
+                default:
+                    // this should never happen
+                    throw new Error('Unexpected error');
+            }
+        });
     }
 
     private static isFhirStructureDefinition(x: any): x is FhirStructureDefinition {
@@ -60,4 +91,15 @@ export class StructureDefinitionImplementationGuides implements ImplementationGu
             typeof x.type === 'string'
         );
     }
+
+    private static isFhirOperationDefinition(x: any): x is FhirOperationDefinition {
+        return (
+            typeof x === 'object' &&
+            x &&
+            x.resourceType === 'OperationDefinition' &&
+            typeof x.url === 'string' &&
+            typeof x.name === 'string' &&
+            typeof x.description === 'string'
+        );
+    }
 }

src/operationDefinitions/OperationDefinitionRegistry.test.ts

@@ -0,0 +1,68 @@
+/*
+ *  Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ */
+
+import { Router } from 'express';
+import ConfigHandler from '../configHandler';
+import { OperationDefinitionRegistry } from './OperationDefinitionRegistry';
+import { OperationDefinitionImplementation } from './types';
+import ResourceHandler from '../router/handlers/resourceHandler';
+
+const fakeRouter = (jest.fn() as unknown) as Router;
+const fakeOperation: OperationDefinitionImplementation = {
+    canonicalUrl: 'https://fwoa.com/operation/fakeOperation',
+    httpVerbs: ['GET'],
+    path: '/Patient/fakeOperation',
+    targetResourceType: 'Patient',
+    requestInformation: {
+        operation: 'read',
+        resourceType: 'Patient',
+    },
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    buildRouter: (resourceHandler: ResourceHandler) => fakeRouter,
+};
+describe('OperationDefinitionRegistry', () => {
+    test('getAllRouters', () => {
+        const configHandlerMock = {
+            getResourceHandler: jest.fn().mockReturnValue({}),
+        };
+
+        const operationDefinitionRegistry = new OperationDefinitionRegistry(
+            (configHandlerMock as unknown) as ConfigHandler,
+            [fakeOperation],
+        );
+
+        expect(operationDefinitionRegistry.getAllRouters()).toHaveLength(1);
+        expect(operationDefinitionRegistry.getAllRouters()[0]).toBe(fakeRouter);
+    });
+
+    test('getOperation', () => {
+        const configHandlerMock = {
+            getResourceHandler: jest.fn().mockReturnValue({}),
+        };
+
+        const operationDefinitionRegistry = new OperationDefinitionRegistry(
+            (configHandlerMock as unknown) as ConfigHandler,
+            [fakeOperation],
+        );
+
+        expect(operationDefinitionRegistry.getOperation('PATCH', '/Patient/fakeOperation')).toBeUndefined();
+        expect(operationDefinitionRegistry.getOperation('GET', '/Patient/someOtherOperation')).toBeUndefined();
+
+        expect(operationDefinitionRegistry.getOperation('GET', '/Patient/fakeOperation')).toBe(fakeOperation);
+    });
+
+    test('ResourceHandler not available', () => {
+        const configHandlerMock = {
+            getResourceHandler: jest.fn().mockReturnValue(undefined),
+        };
+
+        expect(
+            () => new OperationDefinitionRegistry((configHandlerMock as unknown) as ConfigHandler, [fakeOperation]),
+        ).toThrowErrorMatchingInlineSnapshot(
+            `"Failed to initialize operation https://fwoa.com/operation/fakeOperation. Is your FhirConfig correct?"`,
+        );
+    });
+});

src/operationDefinitions/OperationDefinitionRegistry.ts

@@ -0,0 +1,38 @@
+/*
+ *  Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ */
+
+import { Router } from 'express';
+import { OperationDefinitionImplementation } from './types';
+import ConfigHandler from '../configHandler';
+
+export class OperationDefinitionRegistry {
+    private readonly operations: OperationDefinitionImplementation[];
+
+    private readonly routers: Router[];
+
+    constructor(configHandler: ConfigHandler, operations: OperationDefinitionImplementation[]) {
+        this.operations = operations;
+
+        this.routers = operations.map(operation => {
+            const resourceHandler = configHandler.getResourceHandler(operation.targetResourceType);
+            if (!resourceHandler) {
+                throw new Error(
+                    `Failed to initialize operation ${operation.canonicalUrl}. Is your FhirConfig correct?`,
+                );
+            }
+            console.log(`Enabling operation ${operation.canonicalUrl} at ${operation.path}`);
+            return operation.buildRouter(resourceHandler);
+        });
+    }
+
+    getOperation(method: string, path: string): OperationDefinitionImplementation | undefined {
+        return this.operations.find(o => o.path === path && o.httpVerbs.includes(method));
+    }
+
+    getAllRouters(): Router[] {
+        return this.routers;
+    }
+}