ConnectorServiceProxyImpl.java

package com.emasphere.integrationgateway.proxy.operation.connector;

import com.emasphere.directory.client.EmaAuthenticationToken;
import com.emasphere.integrationgateway.model.operation.connector.ConnectorRequestContext;
import com.emasphere.integrationgateway.operation.model.connector.flow.FlowDefinitionReference;
import com.emasphere.integrationgateway.operation.model.connector.flow.FlowDefinitionValidationResult;
import com.emasphere.integrationgateway.operation.model.connector.validation.ValidationResult;
import com.emasphere.integrationgateway.proxy.support.RemotingException;
import org.springframework.core.ParameterizedTypeReference;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import java.util.List;
import java.util.Map;

import static java.util.Arrays.*;
import static org.springframework.http.HttpHeaders.COOKIE;

/**
 * Implementation of the {@link ConnectorServiceProxy connector service proxy}.
 *
 * @author Sebastien Gerard
 */
@Service
public class ConnectorServiceProxyImpl implements ConnectorServiceProxy {

    /**
     * The HTTP header containing the access key to use.
     */
    public static final String ACCESS_KEY_HEADER = "ACCESS_KEY";

    /**
     * The HTTP header containing the user name.
     */
    public static final String USER_NAME_HEADER = "USER_NAME";

    /**
     * The HTTP header containing the tenant id.
     */
    public static final String TENANT_HEADER = "TENANT_ID";

    private final RestTemplate restTemplate;

    public ConnectorServiceProxyImpl() {
        this.restTemplate = new RestTemplate();
    }

    @Override
    public List<FlowDefinitionReference> getAvailableFlows(ConnectorRequestContext context) {
        final String url = context.getDescription().getUrl() + "/flow/available";
        final ResponseEntity<List<FlowDefinitionReference>> responseEntity = restTemplate
                .exchange(
                        url,
                        HttpMethod.GET,
                        createEntity(context, null),
                        new ParameterizedTypeReference<List<FlowDefinitionReference>>() {
                        }
                );

        if (responseEntity.getStatusCode() != HttpStatus.OK) {
            throw new RemotingException("Error while calling [" + url + "] (" + responseEntity.getStatusCode() + ").");
        }

        return responseEntity.getBody();
    }

    @Override
    public FlowDefinitionValidationResult getFlowDefinition(String flowReference, ConnectorRequestContext context) {
        final String url = context.getDescription().getUrl() + "/flow/definition/" + flowReference;
        final ResponseEntity<FlowDefinitionValidationResult> responseEntity = restTemplate
                .exchange(
                        url,
                        HttpMethod.GET,
                        createEntity(context, null),
                        new ParameterizedTypeReference<FlowDefinitionValidationResult>() {
                        }
                );

        if (!asList(HttpStatus.OK, HttpStatus.CREATED).contains(responseEntity.getStatusCode())) {
            throw new RemotingException("Error while calling [" + url + "] (" + responseEntity.getStatusCode() + ").");
        }

        return responseEntity.getBody();
    }

    @Override
    public ValidationResult saveCredentials(Map<String, Object> credentials, ConnectorRequestContext context) {
        final String url = context.getDescription().getUrl() + "/authentication/credentials/config-entries";
        final ResponseEntity<ValidationResult> responseEntity = restTemplate
                .exchange(
                        url,
                        HttpMethod.POST,
                        createEntity(context, credentials),
                        ValidationResult.class
                );

        if (responseEntity.getStatusCode() != HttpStatus.OK) {
            throw new RemotingException("Error while calling [" + url + "] (" + responseEntity.getStatusCode() + ").");
        }

        return responseEntity.getBody();
    }

    @Override
    public ValidationResult checkConnectorConfiguredForCurrentUser(ConnectorRequestContext context) {
        final String url = context.getDescription().getUrl() + "/authentication/credentials/configured";
        final ResponseEntity<ValidationResult> responseEntity = restTemplate
                .exchange(
                        url,
                        HttpMethod.GET,
                        createEntity(context, null),
                        ValidationResult.class
                );

        if (responseEntity.getStatusCode() != HttpStatus.OK) {
            throw new RemotingException("Error while calling [" + url + "] (" + responseEntity.getStatusCode() + ").");
        }

        return responseEntity.getBody();
    }

    /**
     * Creates the header for the specified content.
     */
    private <T> HttpEntity<T> createEntity(ConnectorRequestContext context, T content) {
        final HttpHeaders headers = new HttpHeaders();

        final Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

        if(!(authentication instanceof EmaAuthenticationToken)){
            throw new IllegalStateException("There is no authentication token. Hint: please check the security context.");
        }

        final EmaAuthenticationToken token = (EmaAuthenticationToken) authentication;

        headers.set(ACCESS_KEY_HEADER, context.getAccessKey());
        headers.set(USER_NAME_HEADER, token.getUser().getUsername());
        headers.set(TENANT_HEADER, token.getBaseTenantId());
        headers.set(COOKIE, "SESSION=" + token.getSessionId());

        return new HttpEntity<>(content, headers);
    }

}