error propagation for API calls

src/main/java/io/cdap/plugin/servicenow/ServiceNowBaseConfig.java

@@ -137,7 +137,7 @@ public void validateTable(String tableName, SourceValueType valueType, FailureCo
       // Get the response JSON and fetch the header X-Total-Count. Set the value to recordCount
       requestBuilder.setResponseHeaders(ServiceNowConstants.HEADER_NAME_TOTAL_COUNT);
 
-      apiResponse = serviceNowTableAPIClient.executeGet(requestBuilder.build());
+      apiResponse = serviceNowTableAPIClient.executeGetWithRetries(requestBuilder.build());
       if (serviceNowTableAPIClient.parseResponseToResultListOfMap(apiResponse.getResponseBody()).isEmpty()) {
         // Removed config property as in case of MultiSource, only first table error was populating.
         collector.addFailure("Table: " + tableName + " is empty.", "");

src/main/java/io/cdap/plugin/servicenow/apiclient/ServiceNowAPIException.java

@@ -0,0 +1,36 @@
+package io.cdap.plugin.servicenow.apiclient;
+
+import org.apache.http.HttpResponse;
+
+import javax.annotation.Nullable;
+
+/**
+ * Custom Exception class for propagating API errors/exceptions back to caller.
+ */
+public class ServiceNowAPIException extends Exception {
+
+  @Nullable private final HttpResponse httpResponse;
+  private final boolean isErrorRetryable;
+
+  public ServiceNowAPIException(
+      Throwable t, @Nullable HttpResponse httpResponse, boolean isErrorRetryable) {
+    super(t);
+    this.httpResponse = httpResponse;
+    this.isErrorRetryable = isErrorRetryable;
+  }
+
+  public ServiceNowAPIException(
+      String message, @Nullable HttpResponse httpResponse, boolean isErrorRetryable) {
+    super(message);
+    this.httpResponse = httpResponse;
+    this.isErrorRetryable = isErrorRetryable;
+  }
+
+  public HttpResponse getHttpResponse() {
+    return httpResponse;
+  }
+
+  public boolean isErrorRetryable() {
+    return isErrorRetryable;
+  }
+}

src/main/java/io/cdap/plugin/servicenow/apiclient/ServiceNowTableAPIClientImpl.java

@@ -56,6 +56,7 @@
 import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
+import java.util.function.Predicate;
 import javax.annotation.Nullable;
 
 /**
@@ -109,8 +110,14 @@ public String getAccessTokenRetryableMode() throws ExecutionException, RetryExce
    * @param limit     The number of records to be fetched
    * @return The list of Map; each Map representing a table row
    */
-  public List<Map<String, String>> fetchTableRecords(String tableName, SourceValueType valueType, String startDate,
-                                                     String endDate, int offset, int limit) throws IOException {
+  public List<Map<String, String>> fetchTableRecords(
+      String tableName,
+      SourceValueType valueType,
+      String startDate,
+      String endDate,
+      int offset,
+      int limit)
+      throws IOException, ServiceNowAPIException {
     ServiceNowTableAPIRequestBuilder requestBuilder = new ServiceNowTableAPIRequestBuilder(
       this.conf.getRestApiEndpoint(), tableName, false)
       .setExcludeReferenceLink(true)
@@ -126,10 +133,10 @@ public List<Map<String, String>> fetchTableRecords(String tableName, SourceValue
     try {
       String accessToken = getAccessToken();
       requestBuilder.setAuthHeader(accessToken);
-      RestAPIResponse apiResponse = executeGet(requestBuilder.build());
+      RestAPIResponse apiResponse = executeGetWithRetries(requestBuilder.build());
       return parseResponseToResultListOfMap(apiResponse.getResponseBody());
     } catch (OAuthSystemException e) {
-      throw new RetryableException("Authentication error occurred", e);
+      throw new ServiceNowAPIException(e, null, true);
     } catch (OAuthProblemException e) {
       throw new IOException("Problem occurred while authenticating", e);
     }
@@ -219,8 +226,11 @@ public List<Map<String, String>> fetchTableRecordsRetryableMode(String tableName
       return true;
     };
 
+    Predicate<Throwable> retryableServiceNowExceptionPredicate = t -> (t instanceof ServiceNowAPIException
+        && ((ServiceNowAPIException) t).isErrorRetryable());
+
     Retryer<Boolean> retryer = RetryerBuilder.<Boolean>newBuilder()
-      .retryIfExceptionOfType(RetryableException.class)
+      .retryIfException(retryableServiceNowExceptionPredicate::test)
       .withWaitStrategy(WaitStrategies.exponentialWait(ServiceNowConstants.WAIT_TIME, TimeUnit.MILLISECONDS))
       .withStopStrategy(StopStrategies.stopAfterAttempt(ServiceNowConstants.MAX_NUMBER_OF_RETRY_ATTEMPTS))
       .build();
@@ -266,7 +276,7 @@ public SchemaResponse parseSchemaResponse(String responseBody) {
    * @throws OAuthSystemException
    */
   public Schema fetchTableSchema(String tableName)
-      throws OAuthProblemException, OAuthSystemException, IOException {
+      throws OAuthProblemException, OAuthSystemException, IOException, ServiceNowAPIException {
     return fetchTableSchema(tableName, getAccessToken());
   }
 
@@ -277,14 +287,15 @@ public Schema fetchTableSchema(String tableName)
    * @param accessToken Access Token to use
    * @return schema for given ServiceNow table
    */
-  public Schema fetchTableSchema(String tableName, String accessToken) throws IOException {
+  public Schema fetchTableSchema(String tableName, String accessToken)
+      throws IOException, ServiceNowAPIException {
     ServiceNowTableAPIRequestBuilder requestBuilder = new ServiceNowTableAPIRequestBuilder(
       this.conf.getRestApiEndpoint(), tableName, true)
       .setExcludeReferenceLink(true);
 
     RestAPIResponse apiResponse;
     requestBuilder.setAuthHeader(accessToken);
-    apiResponse = executeGet(requestBuilder.build());
+    apiResponse = executeGetWithRetries(requestBuilder.build());
     SchemaResponse response = parseSchemaResponse(apiResponse.getResponseBody());
     List<ServiceNowColumn> columns = new ArrayList<>();
 
@@ -306,7 +317,7 @@ public Schema fetchTableSchema(String tableName, String accessToken) throws IOEx
    * @throws OAuthSystemException
    */
   public int getTableRecordCount(String tableName)
-      throws OAuthProblemException, OAuthSystemException, IOException {
+      throws OAuthProblemException, OAuthSystemException, IOException, ServiceNowAPIException {
     return getTableRecordCount(tableName, getAccessToken());
   }
 
@@ -318,7 +329,7 @@ public int getTableRecordCount(String tableName)
    * @return the table record count
    * @throws IOException
    */
-  public int getTableRecordCount(String tableName, String accessToken) throws IOException {
+  public int getTableRecordCount(String tableName, String accessToken) throws ServiceNowAPIException {
     ServiceNowTableAPIRequestBuilder requestBuilder = new ServiceNowTableAPIRequestBuilder(
       this.conf.getRestApiEndpoint(), tableName, false)
       .setExcludeReferenceLink(true)
@@ -327,7 +338,7 @@ public int getTableRecordCount(String tableName, String accessToken) throws IOEx
     RestAPIResponse apiResponse = null;
     requestBuilder.setResponseHeaders(ServiceNowConstants.HEADER_NAME_TOTAL_COUNT);
     requestBuilder.setAuthHeader(accessToken);
-    apiResponse = executeGet(requestBuilder.build());
+    apiResponse = executeGetWithRetries(requestBuilder.build());
     return getRecordCountFromHeader(apiResponse);
   }
 
@@ -372,7 +383,7 @@ private String getSystemId(RestAPIResponse restAPIResponse) {
    * @param query The query
    */
   public Map<String, String> getRecordFromServiceNowTable(String tableName, String query)
-      throws OAuthProblemException, OAuthSystemException, IOException {
+      throws OAuthProblemException, OAuthSystemException, IOException, ServiceNowAPIException {
 
     ServiceNowTableAPIRequestBuilder requestBuilder = new ServiceNowTableAPIRequestBuilder(
       this.conf.getRestApiEndpoint(), tableName, false)
@@ -381,7 +392,7 @@ public Map<String, String> getRecordFromServiceNowTable(String tableName, String
     RestAPIResponse restAPIResponse;
     String accessToken = getAccessToken();
     requestBuilder.setAuthHeader(accessToken);
-    restAPIResponse = executeGet(requestBuilder.build());
+    restAPIResponse = executeGetWithRetries(requestBuilder.build());
 
     APIResponse apiResponse = GSON.fromJson(restAPIResponse.getResponseBody(), APIResponse.class);
     return apiResponse.getResult().get(0);

src/main/java/io/cdap/plugin/servicenow/connector/ServiceNowConnector.java

@@ -40,6 +40,7 @@
 import io.cdap.plugin.common.ConfigUtil;
 import io.cdap.plugin.common.Constants;
 import io.cdap.plugin.common.ReferenceNames;
+import io.cdap.plugin.servicenow.apiclient.ServiceNowAPIException;
 import io.cdap.plugin.servicenow.apiclient.ServiceNowTableAPIClientImpl;
 import io.cdap.plugin.servicenow.apiclient.ServiceNowTableAPIRequestBuilder;
 import io.cdap.plugin.servicenow.restapi.RestAPIResponse;
@@ -93,7 +94,7 @@ public BrowseDetail browse(ConnectorContext connectorContext, BrowseRequest brow
     try {
       String accessToken = serviceNowTableAPIClient.getAccessToken();
       return browse(connectorContext, accessToken);
-    } catch (OAuthSystemException | OAuthProblemException e) {
+    } catch (OAuthSystemException | OAuthProblemException | ServiceNowAPIException e) {
       throw new IOException(e);
     }
   }
@@ -102,7 +103,7 @@ public BrowseDetail browse(ConnectorContext connectorContext, BrowseRequest brow
    * Browse Details for the given AccessToken.
    */
   public BrowseDetail browse(ConnectorContext connectorContext,
-                             String accessToken) throws IOException {
+                             String accessToken) throws ServiceNowAPIException {
     int count = 0;
     FailureCollector collector = connectorContext.getFailureCollector();
     config.validateCredentialsFields(collector);
@@ -125,14 +126,15 @@ public BrowseDetail browse(ConnectorContext connectorContext,
   /**
    * @return the list of tables.
    */
-  private TableList listTables(String accessToken) throws IOException {
+  private TableList listTables(String accessToken) throws ServiceNowAPIException {
     ServiceNowTableAPIRequestBuilder requestBuilder = new ServiceNowTableAPIRequestBuilder(
       config.getRestApiEndpoint(), OBJECT_TABLE_LIST, false);
     requestBuilder.setAuthHeader(accessToken);
     requestBuilder.setAcceptHeader(MediaType.APPLICATION_JSON);
     requestBuilder.setContentTypeHeader(MediaType.APPLICATION_JSON);
     ServiceNowTableAPIClientImpl serviceNowTableAPIClient = new ServiceNowTableAPIClientImpl(config);
-    RestAPIResponse apiResponse = serviceNowTableAPIClient.executeGet(requestBuilder.build());
+    RestAPIResponse apiResponse =
+        serviceNowTableAPIClient.executeGetWithRetries(requestBuilder.build());
     return GSON.fromJson(apiResponse.getResponseBody(), TableList.class);
   }
 
@@ -164,13 +166,13 @@ public List<StructuredRecord> sample(ConnectorContext connectorContext, SampleRe
     }
     try {
       return getTableData(table, sampleRequest.getLimit());
-    } catch (OAuthProblemException | OAuthSystemException e) {
-      throw new IOException("Unable to fetch the data.");
+    } catch (OAuthProblemException | OAuthSystemException | ServiceNowAPIException e) {
+      throw new IOException("Unable to fetch the data.", e);
     }
   }
 
   private List<StructuredRecord> getTableData(String tableName, int limit)
-      throws OAuthProblemException, OAuthSystemException, IOException {
+      throws OAuthProblemException, OAuthSystemException, ServiceNowAPIException {
     ServiceNowTableAPIRequestBuilder requestBuilder = new ServiceNowTableAPIRequestBuilder(
       config.getRestApiEndpoint(), tableName, false)
       .setExcludeReferenceLink(true)
@@ -180,7 +182,7 @@ private List<StructuredRecord> getTableData(String tableName, int limit)
     String accessToken = serviceNowTableAPIClient.getAccessToken();
     requestBuilder.setAuthHeader(accessToken);
     requestBuilder.setResponseHeaders(ServiceNowConstants.HEADER_NAME_TOTAL_COUNT);
-    RestAPIResponse apiResponse = serviceNowTableAPIClient.executeGet(requestBuilder.build());
+    RestAPIResponse apiResponse = serviceNowTableAPIClient.executeGetWithRetries(requestBuilder.build());
     List<Map<String, String>> result = serviceNowTableAPIClient.parseResponseToResultListOfMap
       (apiResponse.getResponseBody());
     List<StructuredRecord> recordList = new ArrayList<>();