Import routing-generator

1 files changed, 104 insertions, 0 deletions

diff --git a/routing-generator/src/main/java/com/yahoo/vespa/hosted/routing/nginx/NginxHealthClient.java b/routing-generator/src/main/java/com/yahoo/vespa/hosted/routing/nginx/NginxHealthClient.java
new file mode 100644
index 00000000000..fdfd0f71e96
--- /dev/null
+++ b/routing-generator/src/main/java/com/yahoo/vespa/hosted/routing/nginx/NginxHealthClient.java
@@ -0,0 +1,104 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.routing.nginx;
+
+import com.yahoo.component.AbstractComponent;
+import com.yahoo.component.annotation.Inject;
+import com.yahoo.lang.CachedSupplier;
+import com.yahoo.slime.ArrayTraverser;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.slime.SlimeUtils;
+import com.yahoo.vespa.hosted.routing.status.HealthStatus;
+import com.yahoo.vespa.hosted.routing.status.ServerGroup;
+import com.yahoo.yolean.Exceptions;
+import org.apache.http.client.config.RequestConfig;
+import org.apache.http.client.methods.CloseableHttpResponse;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.apache.http.util.EntityUtils;
+
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.net.URI;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Client for the Nginx upstream health status page served at /health-status.
+ *
+ * @author oyving
+ * @author mpolden
+ */
+public class NginxHealthClient extends AbstractComponent implements HealthStatus {
+
+    private static final URI healthStatusUrl = URI.create("http://localhost:4080/health-status/?format=json");
+    private static final Duration requestTimeout = Duration.ofSeconds(5);
+    private static final Duration cacheTtl = Duration.ofSeconds(5);
+
+    private final CloseableHttpClient httpClient;
+    private final CachedSupplier<ServerGroup> cache = new CachedSupplier<>(this::getStatus, cacheTtl);
+
+    @Inject
+    public NginxHealthClient() {
+        this(
+                HttpClientBuilder.create()
+                                 .setDefaultRequestConfig(RequestConfig.custom()
+                                                                       .setConnectTimeout((int) requestTimeout.toMillis())
+                                                                       .setConnectionRequestTimeout((int) requestTimeout.toMillis())
+                                                                       .setSocketTimeout((int) requestTimeout.toMillis())
+                                                                       .build())
+                                 .build()
+        );
+    }
+
+    NginxHealthClient(CloseableHttpClient client) {
+        this.httpClient = Objects.requireNonNull(client);
+    }
+
+    @Override
+    public ServerGroup servers() {
+        return cache.get();
+    }
+
+    private ServerGroup getStatus() {
+        HttpGet httpGet = new HttpGet(healthStatusUrl);
+        try (CloseableHttpResponse response = httpClient.execute(httpGet)) {
+            String entity = Exceptions.uncheck(() -> EntityUtils.toString(response.getEntity()));
+            if (response.getStatusLine().getStatusCode() / 100 != 2) {
+                throw new IllegalArgumentException("Got status code " + response.getStatusLine().getStatusCode() +
+                                                   " for URL " + healthStatusUrl + ", with response: " + entity);
+            }
+            return parseStatus(entity);
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+
+    private static ServerGroup parseStatus(String json) {
+        Slime slime = SlimeUtils.jsonToSlime(json);
+        Cursor root = slime.get();
+        List<ServerGroup.Server> servers = new ArrayList<>();
+        Cursor serversObject = root.field("servers");
+
+        Cursor streamArray = serversObject.field("stream");
+        Cursor serverArray = serversObject.field("server"); // TODO(mpolden): Remove after 2022-03-01
+        Cursor array = streamArray.valid() ? streamArray : serverArray;
+
+        array.traverse((ArrayTraverser) (idx, inspector) -> {
+            String upstreamName = inspector.field("upstream").asString();
+            String hostPort = inspector.field("name").asString();
+            boolean up = "up".equals(inspector.field("status").asString());
+            servers.add(new ServerGroup.Server(upstreamName, hostPort, up));
+        });
+        return new ServerGroup(servers);
+    }
+
+    @Override
+    public void deconstruct() {
+        Exceptions.uncheck(httpClient::close);
+    }
+
+}