better GOAWAY handling

gradle.properties

@@ -1,3 +1,3 @@
 group = org.xbib
 name = oai
-version = 4.0.0
+version = 4.0.1

gradle/test/junit5.gradle

@@ -26,6 +26,7 @@ test {
     systemProperty 'io.netty.recycler.maxCapacityPerThread', '0'
     systemProperty 'io.netty.transport.noNative', 'true'
     testLogging {
+        showStandardStreams = true
         events 'STARTED', 'PASSED', 'FAILED', 'SKIPPED'
     }
     afterSuite { desc, result ->

oai-client/src/main/java/org/xbib/oai/client/OAIClient.java

@@ -198,7 +198,20 @@ public class OAIClient {
                             .build();
                     logger.log(Level.INFO, "sending " + httpRequest);
                     if (consumer != null) {
-                        HttpResponse<byte[]> httpResponse = httpClient.send(httpRequest, HttpResponse.BodyHandlers.ofByteArray());
+                        int retrycount = 3;
+                        HttpResponse<byte[]> httpResponse = null;
+                        while (httpResponse == null && retrycount > 0) {
+                            try {
+                                httpResponse = httpClient.send(httpRequest, HttpResponse.BodyHandlers.ofByteArray());
+                            } catch (IOException e) {
+                                // e.g. java.io.IOException: GOAWAY received
+                                //	at java.net.http/jdk.internal.net.http.HttpClientImpl.send(Unknown Source)
+                                logger.log(Level.WARNING, e.getMessage(), e);
+                                retrycount--;
+                                Thread.sleep(5000L);
+                            }
+                        }
+                        if (httpResponse != null) {
                             int status = httpResponse.statusCode();
                             String contentType = httpResponse.headers().firstValue("content-type").orElse(null);
                             String retryAfter = httpResponse.headers().firstValue("retry-after").orElse(null);
@@ -210,6 +223,7 @@ public class OAIClient {
                             if (b.length > 0) {
                                 consumer.accept(new ByteArrayInputStream(b));
                             }
+                        }
                     } else {
                         HttpResponse<String> httpResponse = httpClient.send(httpRequest, HttpResponse.BodyHandlers.ofString());
                         int status = httpResponse.statusCode();

oai-client/src/main/java/org/xbib/oai/client/listrecords/ListRecordsResponse.java

@@ -18,6 +18,8 @@ import java.io.StringWriter;
 import java.time.Instant;
 import java.time.format.DateTimeFormatter;
 import java.time.temporal.ChronoUnit;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import javax.xml.transform.Source;
 import javax.xml.transform.Transformer;
@@ -28,6 +30,8 @@ import javax.xml.transform.stream.StreamResult;
 
 public class ListRecordsResponse implements OAIResponse {
 
+    private static final Logger logger = Logger.getLogger(ListRecordsResponse.class.getName());
+
     private final ListRecordsRequest request;
 
     private ListRecordsFilterReader filterreader;
@@ -54,35 +58,44 @@ public class ListRecordsResponse implements OAIResponse {
         return error;
     }
 
-    public void receivedResponse(String message, int status, String contentType, String retryAfter, SplitWriter splitWriter) throws OAIException {
-        if (status == 503) {
+    public void receivedResponse(String message,
+                                 int status,
+                                 String contentType,
+                                 String retryAfter,
+                                 SplitWriter splitWriter) throws OAIException {
         long secs = retryAfterMillis / 1000;
         if (retryAfter != null) {
-                secs = Long.parseLong(retryAfter);
             if (!isDigits(retryAfter)) {
                 // parse RFC date, e.g. Fri, 31 Dec 1999 23:59:59 GMT
                 Instant instant = Instant.from(DateTimeFormatter.RFC_1123_DATE_TIME.parse(retryAfter));
                 secs = ChronoUnit.SECONDS.between(instant, Instant.now());
-                }
+            } else {
+                secs = Long.parseLong(retryAfter);
             }
             request.setRetry(true);
+        }
+        if (status == 503) {
             try {
                 if (secs > 0L) {
+                    logger.log(Level.INFO, "waiting " + secs + " seconds");
                     Thread.sleep(1000 * secs);
                 }
             } catch (InterruptedException e) {
                 Thread.currentThread().interrupt();
             }
+            // early return
             return;
-        }
-        if (status == 429) {
+        } else if (status == 429) {
             try {
-                Thread.sleep(10000L);
+                if (secs > 0L) {
+                    logger.log(Level.INFO, "waiting " + secs + " seconds");
+                    Thread.sleep(1000 * secs);
+                }
             } catch (InterruptedException e) {
-                // ignore
+                Thread.currentThread().interrupt();
             }
-        }
-        if (status != 200) {
+            // do not return, try to evaluate returned message if present
+        } else if (status != 200) {
             throw new OAIException("status  = " + status + " response = " + message);
         }
         // activate XSLT only if OAI XML content type is returned
@@ -138,5 +151,4 @@ public class ListRecordsResponse implements OAIResponse {
     public ResumptionToken<?> getResumptionToken() {
         return filterreader != null ? filterreader.getResumptionToken() : null;
     }
-
 }

oai-client/src/test/java/org/xbib/oai/client/test/DNBClientTest.java

@@ -7,7 +7,6 @@ import org.xbib.oai.client.SplitWriter;
 
 import java.time.Instant;
 
-@Disabled("port is locked")
 class DNBClientTest {
 
     @Test