public RequestDecorator forAuthType()

in aws-api/src/main/java/com/amplifyframework/api/aws/auth/ApiRequestDecoratorFactory.java [109:195]
78 lines of code
17 McCabe index (conditional complexity)

    public RequestDecorator forAuthType(@NonNull AuthorizationType authorizationType) throws ApiAuthException {
        switch (authorizationType) {
            case AMAZON_COGNITO_USER_POOLS:
                // Note that if there was no user-provided cognito provider passed in to initialize
                // the API plugin, we will try to default to using the DefaultCognitoUserPoolsAuthProvider.
                //  If that fails, we then have no choice but to bubble up the error.
                CognitoUserPoolsAuthProvider cognitoUserPoolsAuthProvider =
                        apiAuthProviders.getCognitoUserPoolsAuthProvider() != null ?
                                apiAuthProviders.getCognitoUserPoolsAuthProvider() :
                                new DefaultCognitoUserPoolsAuthProvider();
                // By calling getLatestAuthToken() here instead of inside the lambda block, makes the exception
                // handling a little bit cleaner. If getLatestAuthToken() is called from inside the lambda expression
                // below, we'd have to surround it with a try catch. By doing it this way, if there's a problem,
                // the ApiException will just be bubbled up. Same for OPENID_CONNECT.
                final String token;
                try {
                    token = cognitoUserPoolsAuthProvider.getLatestAuthToken();
                } catch (ApiException exception) {
                    throw new ApiAuthException("Failed to retrieve auth token from Cognito provider.",
                                                            exception,
                                                            "Check the application logs for details.");
                }
                return new TokenRequestDecorator(() -> token);
            case OPENID_CONNECT:
                if (apiAuthProviders.getOidcAuthProvider() == null) {
                    throw new ApiAuthException("Attempting to use OPENID_CONNECT authorization " +
                                                                "without an OIDC provider.",
                                                            "Configure an OidcAuthProvider when initializing " +
                                                                "the API plugin.");
                }
                final String oidcToken;
                try {
                    oidcToken = apiAuthProviders.getOidcAuthProvider().getLatestAuthToken();
                } catch (ApiException exception) {
                    throw new ApiAuthException("Failed to retrieve auth token from OIDC provider.",
                                               exception,
                                               "Check the application logs for details.");
                }
                return new TokenRequestDecorator(() -> oidcToken);
            case AWS_LAMBDA:
                if (apiAuthProviders.getFunctionAuthProvider() == null) {
                    throw new ApiAuthException("Attempting to use AWS_LAMBDA authorization " +
                            "without a provider implemented.",
                            "Configure a FunctionAuthProvider when initializing the API plugin.");
                }
                final String functionToken;
                try {
                    functionToken = apiAuthProviders.getFunctionAuthProvider().getLatestAuthToken();
                } catch (ApiException exception) {
                    throw new ApiAuthException("Failed to retrieve auth token from function auth provider.",
                            exception,
                            "Check the application logs for details.");
                }
                return new TokenRequestDecorator(() -> functionToken);
            case API_KEY:
                if (apiAuthProviders.getApiKeyAuthProvider() != null) {
                    return new ApiKeyRequestDecorator(apiAuthProviders.getApiKeyAuthProvider());
                } else if (apiKey != null) {
                    return new ApiKeyRequestDecorator(() -> apiKey);
                } else {
                    throw new ApiAuthException("Attempting to use API_KEY authorization without " +
                                                "an API key provider or an API key in the config file",
                                                "Verify that an API key is in the config file or an " +
                                                "ApiKeyAuthProvider is setup during the API " +
                                                "plugin initialization.");
                }
            case AWS_IAM:
                AWSCredentialsProvider credentialsProvider = apiAuthProviders.getAWSCredentialsProvider() != null
                        ? apiAuthProviders.getAWSCredentialsProvider()
                        : getDefaultCredentialsProvider();

                final AWS4Signer signer;
                final String serviceName;
                if (endpointType == EndpointType.GRAPHQL) {
                    signer = new AppSyncV4Signer(region);
                    serviceName = APP_SYNC_SERVICE_NAME;
                } else {
                    signer = new ApiGatewayIamSigner(region);
                    serviceName = API_GATEWAY_SERVICE_NAME;
                }

                return new IamRequestDecorator(signer, credentialsProvider, serviceName);
            case NONE:
            default:
                return NO_OP_REQUEST_DECORATOR;
        }
    }