Add geo data cache

Signed-off-by: Heemin Kim <[email protected]>

src/main/java/org/opensearch/geospatial/ip2geo/cache/GeoDataCache.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.geospatial.ip2geo.cache;
+
+import lombok.AllArgsConstructor;
+import lombok.EqualsAndHashCode;
+import org.opensearch.common.cache.Cache;
+import org.opensearch.common.cache.CacheBuilder;
+
+import java.net.InetAddress;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.concurrent.ExecutionException;
+import java.util.function.Function;
+
+public class GeoDataCache {
+    private Cache<CacheKey, Map<String, Object>> cache;
+
+    // package private for testing
+    public GeoDataCache(final long maxSize) {
+        if (maxSize < 0) {
+            throw new IllegalArgumentException("ip2geo max cache size must be 0 or greater");
+        }
+        this.cache = CacheBuilder.<CacheKey, Map<String, Object>>builder().setMaximumWeight(maxSize).build();
+    }
+
+    public Map<String, Object> putIfAbsent (
+        final String datasourceName,
+        final InetAddress ip,
+        final Function<InetAddress, Map<String, Object>> retrieveFunction
+    ) throws ExecutionException {
+        CacheKey cacheKey = new CacheKey(datasourceName, ip);
+        return cache.computeIfAbsent(cacheKey, key -> retrieveFunction.apply(key.ip));
+    }
+
+    public Map<String, Object> get (
+        final String datasourceName,
+        final InetAddress ip) {
+        return cache.get(new CacheKey(datasourceName, ip));
+    }
+
+    /**
+     * Create a new cache with give size and replace existing cache
+     *
+     * @param maxSize
+     */
+    public void updateMaxSize(final long maxSize) {
+        if (maxSize < 0) {
+            throw new IllegalArgumentException("ip2geo max cache size must be 0 or greater");
+        }
+        this.cache = CacheBuilder.<CacheKey, Map<String, Object>>builder().setMaximumWeight(maxSize).build();
+    }
+
+    /**
+     * Invalidate all cached values of a given datasource
+     *
+     * @param datasourceName
+     */
+    public void invalidate(final String datasourceName) {
+        Iterator<CacheKey> it = cache.keys().iterator();
+        while (it.hasNext()) {
+            CacheKey cacheKey = it.next();
+            if (datasourceName.equals(cacheKey.datasourceName)) {
+                cache.invalidate(cacheKey);
+            }
+        }
+    }
+
+    @AllArgsConstructor
+    @EqualsAndHashCode
+    private static class CacheKey {
+        private final String datasourceName;
+        private final InetAddress ip;
+    }
+}

src/test/java/org/opensearch/geospatial/ip2geo/cache/GeoDataCacheTests.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.geospatial.ip2geo.cache;
+
+import lombok.SneakyThrows;
+import org.opensearch.geospatial.GeospatialTestHelper;
+import org.opensearch.geospatial.ip2geo.Ip2GeoTestCase;
+
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+
+public class GeoDataCacheTests extends Ip2GeoTestCase {
+
+    /**
+     * Test a correctness of invalidate
+     *
+     * 1. Fill the cache with old data with datasource 1
+     * 2. Run three threads which will
+     *    add value for datasource 1 with new data
+     *    add value for datasource 2 with new data
+     *    invalidate old data for datasource 1
+     * 3. Verify all old data for datasource 1 is invalidated
+     */
+    @SneakyThrows
+    public void testInvalidate_whenCalled_thenInvalidate() {
+        int cacheSize = 100000;
+        GeoDataCache geoDataCache = new GeoDataCache(cacheSize);
+        String datasource1 = "datasource1";
+        String datasource2 = "datasource2";
+        List<InetAddress> ips = new ArrayList<>(cacheSize);
+
+        // Fill the cache with old data for datasource 1
+        Map<String, Object> oldData = Map.of("old", "old");
+        for (int i = 0; i < cacheSize; i++) {
+            InetAddress ip = randomIp(false);
+            ips.add(ip);
+            geoDataCache.putIfAbsent(datasource1, ip, addr -> oldData);
+        }
+
+        ExecutorService executor = Executors.newFixedThreadPool(3);
+        Map<String, Object> newData = Map.of("new", "new");
+        executor.submit(() -> {
+            while (executor.isShutdown() == false) {
+                try {
+                    InetAddress ip = randomIp(false);
+                    geoDataCache.putIfAbsent(datasource1, ip, addr -> newData);
+                    Thread.yield();
+                } catch (Exception e) {
+                    throw new RuntimeException(e);
+                }
+            }
+        });
+
+        executor.submit(() -> {
+            while (executor.isShutdown() == false) {
+                try {
+                    InetAddress ip = randomIp(false);
+                    geoDataCache.putIfAbsent(datasource2, ip, addr -> newData);
+                    Thread.yield();
+                } catch (Exception e) {
+                    throw new RuntimeException(e);
+                }
+            }
+        });
+
+        Future task = executor.submit(() -> {
+            geoDataCache.invalidate(datasource1);
+        });
+
+        while (task.isDone() == false) {
+            Thread.yield();
+        }
+        executor.shutdown();
+
+        // Verify
+        assertTrue(ips.stream().filter(ip -> geoDataCache.get(datasource1, ip) != null).noneMatch(ip -> geoDataCache.get(datasource1, ip).containsKey("old")));
+    }
+
+    @SneakyThrows
+    public void testUpdateMaxSize_whenCalled_thenNewCacheIsCreated() {
+        int cacheSize = 10;
+        String datasource = GeospatialTestHelper.randomLowerCaseString();
+        GeoDataCache geoDataCache = new GeoDataCache(cacheSize);
+        List<InetAddress> ips = new ArrayList<>(cacheSize);
+        for (int i = 0; i < cacheSize; i++) {
+            InetAddress ip = randomIp(false);
+            ips.add(ip);
+            geoDataCache.putIfAbsent(datasource, ip, addr -> Collections.emptyMap());
+        }
+
+        // Verify all data exist in the cache
+        assertTrue(ips.stream().allMatch(ip -> geoDataCache.get(datasource, ip) != null));
+
+        // Update cache size
+        int newCacheSize = 5;
+        geoDataCache.updateMaxSize(newCacheSize);
+
+        // Verify all data is gone from the cache
+        assertTrue(ips.stream().allMatch(ip -> geoDataCache.get(datasource, ip) == null));
+
+        // Add cache size + 1 items
+        InetAddress firstIp = randomIp(false);
+        geoDataCache.putIfAbsent(datasource, firstIp, addr -> Collections.emptyMap());
+        for (int i = 0; i < cacheSize; i++) {
+            geoDataCache.putIfAbsent(datasource, randomIp(false), addr -> Collections.emptyMap());
+        }
+
+        // Verify the first item is not available in the cache
+        assertNull(geoDataCache.get(datasource, firstIp));
+    }
+}