Read service specific endpoints from env/config (#1014)

.changeset/cool-mugs-design.md

@@ -0,0 +1,5 @@
+---
+"@smithy/middleware-endpoint": minor
+---
+
+Read service specific endpoints from env/config

packages/middleware-endpoint/package.json

@@ -24,6 +24,7 @@
   "license": "Apache-2.0",
   "dependencies": {
     "@smithy/middleware-serde": "workspace:^",
+    "@smithy/node-config-provider": "workspace:^",
     "@smithy/types": "workspace:^",
     "@smithy/url-parser": "workspace:^",
     "@smithy/util-middleware": "workspace:^",
@@ -49,6 +50,12 @@
   "files": [
     "dist-*/**"
   ],
+  "browser": {
+    "./dist-es/adaptors/getEndpointFromConfig": "./dist-es/adaptors/getEndpointFromConfig.browser"
+  },
+  "react-native": {
+    "./dist-es/adaptors/getEndpointFromConfig": "./dist-es/adaptors/getEndpointFromConfig.browser"
+  },
   "homepage": "https://github.com/awslabs/smithy-typescript/tree/main/packages/middleware-endpoint",
   "repository": {
     "type": "git",

packages/middleware-endpoint/src/adaptors/getEndpointFromConfig.browser.ts

@@ -0,0 +1 @@
+export const getEndpointFromConfig = async (serviceId: string) => undefined;

packages/middleware-endpoint/src/adaptors/getEndpointFromConfig.ts

@@ -0,0 +1,5 @@
+import { loadConfig } from "@smithy/node-config-provider";
+
+import { getEndpointUrlConfig } from "./getEndpointUrlConfig";
+
+export const getEndpointFromConfig = async (serviceId: string) => loadConfig(getEndpointUrlConfig(serviceId))();

packages/middleware-endpoint/src/adaptors/getEndpointFromInstructions.ts

@@ -4,6 +4,8 @@ import { EndpointResolvedConfig } from "../resolveEndpointConfig";
 import { resolveParamsForS3 } from "../service-customizations";
 import { EndpointParameterInstructions } from "../types";
 import { createConfigValueProvider } from "./createConfigValueProvider";
+import { getEndpointFromConfig } from "./getEndpointFromConfig";
+import { toEndpointV1 } from "./toEndpointV1";
 
 /**
  * @internal
@@ -36,6 +38,13 @@ export const getEndpointFromInstructions = async <
   clientConfig: Partial<EndpointResolvedConfig<T>> & Config,
   context?: HandlerExecutionContext
 ): Promise<EndpointV2> => {
+  if (!clientConfig.endpoint) {
+    const endpointFromConfig = await getEndpointFromConfig(clientConfig.serviceId || "");
+    if (endpointFromConfig) {
+      clientConfig.endpoint = () => Promise.resolve(toEndpointV1(endpointFromConfig));
+    }
+  }
+
   const endpointParams = await resolveParams(commandInput, instructionsSupplier, clientConfig);
 
   if (typeof clientConfig.endpointProvider !== "function") {

packages/middleware-endpoint/src/adaptors/getEndpointUrlConfig.spec.ts

@@ -0,0 +1,89 @@
+import { CONFIG_PREFIX_SEPARATOR } from "@smithy/shared-ini-file-loader";
+
+import { getEndpointUrlConfig } from "./getEndpointUrlConfig";
+
+const ENV_ENDPOINT_URL = "AWS_ENDPOINT_URL";
+const CONFIG_ENDPOINT_URL = "endpoint_url";
+
+describe(getEndpointUrlConfig.name, () => {
+  const serviceId = "foo";
+  const endpointUrlConfig = getEndpointUrlConfig(serviceId);
+
+  const mockEndpoint = "https://mock-endpoint.com";
+  const ORIGINAL_ENV = process.env;
+
+  beforeEach(() => {
+    process.env = {};
+  });
+
+  afterEach(() => {
+    process.env = ORIGINAL_ENV;
+  });
+
+  describe("environmentVariableSelector", () => {
+    beforeEach(() => {
+      process.env[ENV_ENDPOINT_URL] = mockEndpoint;
+    });
+
+    it.each([
+      ["foo", `${ENV_ENDPOINT_URL}_FOO`],
+      ["foobar", `${ENV_ENDPOINT_URL}_FOOBAR`],
+      ["foo bar", `${ENV_ENDPOINT_URL}_FOO_BAR`],
+    ])("returns endpoint for '%s' from environment variable %s", (serviceId, envKey) => {
+      const serviceMockEndpoint = `${mockEndpoint}/${envKey}`;
+      process.env[envKey] = serviceMockEndpoint;
+
+      const endpointUrlConfig = getEndpointUrlConfig(serviceId);
+      expect(endpointUrlConfig.environmentVariableSelector(process.env)).toEqual(serviceMockEndpoint);
+    });
+
+    it(`returns endpoint from environment variable ${ENV_ENDPOINT_URL}`, () => {
+      expect(endpointUrlConfig.environmentVariableSelector(process.env)).toEqual(mockEndpoint);
+    });
+
+    it("returns undefined, if endpoint not available in environment variables", () => {
+      process.env[ENV_ENDPOINT_URL] = undefined;
+      expect(endpointUrlConfig.environmentVariableSelector(process.env)).toBeUndefined();
+    });
+  });
+
+  describe("configFileSelector", () => {
+    it.each([
+      ["foo", "foo"],
+      ["foobar", "foobar"],
+      ["foo bar", "foo_bar"],
+    ])("returns endpoint for '%s' from config file '%s'", (serviceId, serviceConfigId) => {
+      const servicesSectionPrefix = "services";
+      const servicesSectionName = "config-services";
+      const serviceMockEndpoint = `${mockEndpoint}/${serviceConfigId}`;
+
+      const profile = {
+        [servicesSectionPrefix]: servicesSectionName,
+        [CONFIG_ENDPOINT_URL]: mockEndpoint,
+      };
+
+      const config = {
+        [serviceId]: profile,
+        [[servicesSectionPrefix, servicesSectionName].join(CONFIG_PREFIX_SEPARATOR)]: {
+          [[serviceConfigId, CONFIG_ENDPOINT_URL].join(CONFIG_PREFIX_SEPARATOR)]: serviceMockEndpoint,
+        },
+      };
+
+      const endpointUrlConfig = getEndpointUrlConfig(serviceId);
+      expect(endpointUrlConfig.configFileSelector(profile, config)).toEqual(serviceMockEndpoint);
+    });
+
+    it(`returns endpoint from config ${CONFIG_ENDPOINT_URL}`, () => {
+      const profile = { [CONFIG_ENDPOINT_URL]: mockEndpoint };
+      expect(endpointUrlConfig.configFileSelector(profile)).toEqual(mockEndpoint);
+    });
+
+    it("returns undefined, if endpoint not available in config", () => {
+      expect(endpointUrlConfig.environmentVariableSelector({})).toBeUndefined();
+    });
+  });
+
+  it("returns undefined by default", () => {
+    expect(endpointUrlConfig.default).toBeUndefined();
+  });
+});

packages/middleware-endpoint/src/adaptors/getEndpointUrlConfig.ts

@@ -0,0 +1,41 @@
+import { LoadedConfigSelectors } from "@smithy/node-config-provider";
+import { CONFIG_PREFIX_SEPARATOR } from "@smithy/shared-ini-file-loader";
+
+const ENV_ENDPOINT_URL = "AWS_ENDPOINT_URL";
+const CONFIG_ENDPOINT_URL = "endpoint_url";
+
+export const getEndpointUrlConfig = (serviceId: string): LoadedConfigSelectors<string | undefined> => ({
+  environmentVariableSelector: (env) => {
+    // The value provided by a service-specific environment variable.
+    const serviceSuffixParts = serviceId.split(" ").map((w) => w.toUpperCase());
+    const serviceEndpointUrl = env[[ENV_ENDPOINT_URL, ...serviceSuffixParts].join("_")];
+    if (serviceEndpointUrl) return serviceEndpointUrl;
+
+    // The value provided by the global endpoint environment variable.
+    const endpointUrl = env[ENV_ENDPOINT_URL];
+    if (endpointUrl) return endpointUrl;
+
+    return undefined;
+  },
+
+  configFileSelector: (profile, config) => {
+    // The value provided by a service-specific parameter from a services definition section
+    if (config && profile.services) {
+      const servicesSection = config[["services", profile.services].join(CONFIG_PREFIX_SEPARATOR)];
+      if (servicesSection) {
+        const servicePrefixParts = serviceId.split(" ").map((w) => w.toLowerCase());
+        const endpointUrl =
+          servicesSection[[servicePrefixParts.join("_"), CONFIG_ENDPOINT_URL].join(CONFIG_PREFIX_SEPARATOR)];
+        if (endpointUrl) return endpointUrl;
+      }
+    }
+
+    // The value provided by the global parameter from a profile in the shared configuration file.
+    const endpointUrl = profile[CONFIG_ENDPOINT_URL];
+    if (endpointUrl) return endpointUrl;
+
+    return undefined;
+  },
+
+  default: undefined,
+});

packages/middleware-endpoint/src/resolveEndpointConfig.ts

@@ -89,6 +89,12 @@ export interface EndpointResolvedConfig<T extends EndpointParameters = EndpointP
    * Resolved value for input {@link EndpointsInputConfig.useFipsEndpoint}
    */
   useFipsEndpoint: Provider<boolean>;
+
+  /**
+   * Unique service identifier.
+   * @internal
+   */
+  serviceId?: string;
 }
 
 /**

yarn.lock

@@ -2071,6 +2071,7 @@ __metadata:
   resolution: "@smithy/middleware-endpoint@workspace:packages/middleware-endpoint"
   dependencies:
     "@smithy/middleware-serde": "workspace:^"
+    "@smithy/node-config-provider": "workspace:^"
     "@smithy/types": "workspace:^"
     "@smithy/url-parser": "workspace:^"
     "@smithy/util-middleware": "workspace:^"