Add MapFailureStrategy option (#21)

* Add MapFailureStrategy option that will control the behaviour of MapFunc and MapAndEncryptFunc. The change will also influence classes that implements the Mapper interface. Remove MappingNotFoundException from the Mapper interface since it should no longer be used for mapping failures.
statisticsnorway · Apr 9, 2024 · f372aa4 · f372aa4
1 parent d69bb7e
commit f372aa4
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Showing 10 changed files with 94 additions and 31 deletions.
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -23,6 +23,7 @@ jobs:
         with:
           java-version: 21
           distribution: zulu
+          cache: maven
 
       - name: Authenticate to Google Cloud
         id: auth

diff --git a/src/main/java/no/ssb/dapla/dlp/pseudo/func/composite/MapAndEncryptFunc.java b/src/main/java/no/ssb/dapla/dlp/pseudo/func/composite/MapAndEncryptFunc.java
@@ -86,6 +86,9 @@ private PseudoFuncOutput transform(PseudoFuncInput input,
                                        Function<PseudoFuncInput, PseudoFuncOutput> inner,
                                        Function<PseudoFuncInput, PseudoFuncOutput> outer) {
         final PseudoFuncOutput innerOutput = inner.apply(input);
+        if (innerOutput.getValue() == null) {
+            return innerOutput;
+        }
         final PseudoFuncOutput outerOutput = outer.apply(
                 PseudoFuncInput.of(innerOutput.getValue()));
         innerOutput.getWarnings().forEach(outerOutput::addWarning);

diff --git a/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MapFailureStrategy.java b/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MapFailureStrategy.java
@@ -0,0 +1,6 @@
+package no.ssb.dapla.dlp.pseudo.func.map;
+
+public enum MapFailureStrategy {
+    RETURN_NULL,
+    RETURN_ORIGINAL
+}
diff --git a/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MapFuncConfig.java b/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MapFuncConfig.java
@@ -9,10 +9,12 @@
 public class MapFuncConfig {
     private final String context;
     private final String snapshotDate;
+    private final MapFailureStrategy mapFailureStrategy;
 
     @UtilityClass
     public static class Param {
         public static final String CONTEXT = "context";
         public static final String SNAPSHOT_DATE = "snapshotDate";
+        public static final String MAP_FAILURE_STRATEGY = "failureStrategy";
     }
 }
diff --git a/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MapFuncConfigService.java b/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MapFuncConfigService.java
@@ -1,5 +1,7 @@
 package no.ssb.dapla.dlp.pseudo.func.map;
 import no.ssb.dapla.dlp.pseudo.func.PseudoFuncConfig;
+
+import static no.ssb.dapla.dlp.pseudo.func.map.MapFuncConfig.Param.MAP_FAILURE_STRATEGY;
 import static no.ssb.dapla.dlp.pseudo.func.map.MapFuncConfig.Param.SNAPSHOT_DATE;
 
 public class MapFuncConfigService {
@@ -8,6 +10,8 @@ public MapFuncConfig resolve(PseudoFuncConfig genericConfig) {
 
         return MapFuncConfig.builder()
                 .snapshotDate(genericConfig.get(SNAPSHOT_DATE, String.class).orElse(null))
+                .mapFailureStrategy(genericConfig.get(MAP_FAILURE_STRATEGY, MapFailureStrategy.class)
+                        .orElse(MapFailureStrategy.RETURN_ORIGINAL))
                 .context(context)
                 .build();
     }

diff --git a/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/Mapper.java b/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/Mapper.java
@@ -9,8 +9,8 @@ public interface Mapper {
 
     void init(PseudoFuncInput data);
     void setConfig(Map<String, Object> config);
-    PseudoFuncOutput map(PseudoFuncInput data) throws MappingNotFoundException;
+    PseudoFuncOutput map(PseudoFuncInput data);
 
-    PseudoFuncOutput restore(PseudoFuncInput mapped) throws MappingNotFoundException;
+    PseudoFuncOutput restore(PseudoFuncInput mapped);
 
 }
diff --git a/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MappingNotFoundException.java b/src/main/java/no/ssb/dapla/dlp/pseudo/func/map/MappingNotFoundException.java
diff --git a/src/test/java/no/ssb/dapla/dlp/pseudo/func/composite/MapAndEncryptFuncTest.java b/src/test/java/no/ssb/dapla/dlp/pseudo/func/composite/MapAndEncryptFuncTest.java
@@ -8,8 +8,9 @@
 import no.ssb.dapla.dlp.pseudo.func.PseudoFuncOutput;
 import no.ssb.dapla.dlp.pseudo.func.fpe.FpeFunc;
 import no.ssb.dapla.dlp.pseudo.func.fpe.FpeFuncConfig;
+import no.ssb.dapla.dlp.pseudo.func.map.MapFailureStrategy;
 import no.ssb.dapla.dlp.pseudo.func.map.MapFunc;
-import no.ssb.dapla.dlp.pseudo.func.map.MappingNotFoundException;
+import no.ssb.dapla.dlp.pseudo.func.map.MapFuncConfig;
 import no.ssb.dapla.dlp.pseudo.func.map.TestMapper;
 import org.junit.jupiter.api.Test;
 
@@ -19,24 +20,25 @@
 public class MapAndEncryptFuncTest {
     private static final String BASE64_ENCODED_KEY = "w0/G6A5e/KHtTo31FD6mhhS1Tkga43l79IBK24gM4F8=";
 
-    final PseudoFuncConfig config = new PseudoFuncConfig(ImmutableMap.of(
-            PseudoFuncConfig.Param.FUNC_DECL, "map-fpe-test",
-            PseudoFuncConfig.Param.FUNC_IMPL, MapAndEncryptFunc.class.getName(),
-            MapAndEncryptFuncConfig.Param.MAP_FUNC_IMPL, MapFunc.class.getName(),
-            MapAndEncryptFuncConfig.Param.ENCRYPTION_FUNC_IMPL, FpeFunc.class.getName(),
-            FpeFuncConfig.Param.ALPHABET, "alphanumeric+whitespace",
-            FpeFuncConfig.Param.KEY_ID, "keyId1",
-            FpeFuncConfig.Param.KEY_DATA, BASE64_ENCODED_KEY
-
-    ));
+    private PseudoFuncConfig getConfig() {
+        return new PseudoFuncConfig(ImmutableMap.of(
+                PseudoFuncConfig.Param.FUNC_DECL, "map-fpe-test",
+                PseudoFuncConfig.Param.FUNC_IMPL, MapAndEncryptFunc.class.getName(),
+                MapAndEncryptFuncConfig.Param.MAP_FUNC_IMPL, MapFunc.class.getName(),
+                MapAndEncryptFuncConfig.Param.ENCRYPTION_FUNC_IMPL, FpeFunc.class.getName(),
+                FpeFuncConfig.Param.ALPHABET, "alphanumeric+whitespace",
+                FpeFuncConfig.Param.KEY_ID, "keyId1",
+                FpeFuncConfig.Param.KEY_DATA, BASE64_ENCODED_KEY
+        ));
+    }
     /*
      * This test should transform OriginalValue -> MappedValue -> FPE encrypted MappedValue
      * (and back)
      */
     @Test
     public void transformAndRestore() {
         String expectedVal = "ygd1M9at1nK"; // FPE encrypted MappedValue
-        PseudoFunc func = PseudoFuncFactory.create(config);
+        PseudoFunc func = PseudoFuncFactory.create(getConfig());
 
         PseudoFuncOutput pseudonymized = func.apply(PseudoFuncInput.of(TestMapper.ORIGINAL));
         assertThat(pseudonymized.getValue()).isEqualTo(expectedVal);
@@ -45,22 +47,41 @@ public void transformAndRestore() {
         assertThat(depseudonymized.getValue()).isEqualTo(TestMapper.ORIGINAL);
     }
 
+    @Test
+    public void transformAndRestoreWithMissingStrategyIgnore() {
+        // Using MapFailureStrategy.IGNORE one can successfully map and encrypt "gibberish"
+        // and get the same decrypted result back - although the Mapper function didn't find
+        // a mapping for "gibberish"
+        String originalVal = "gibberish";
+        String expectedVal = "J0LjYPO9f"; // FPE encrypted originalVal
+        final PseudoFuncConfig config = getConfig();
+        config.add(MapFuncConfig.Param.MAP_FAILURE_STRATEGY, MapFailureStrategy.RETURN_ORIGINAL);
+        PseudoFunc func = PseudoFuncFactory.create(config);
+
+        PseudoFuncOutput pseudonymized = func.apply(PseudoFuncInput.of(originalVal));
+        assertThat(pseudonymized.getValue()).isEqualTo(expectedVal);
+
+        PseudoFuncOutput depseudonymized = func.restore(PseudoFuncInput.of(pseudonymized.getValue()));
+        assertThat(depseudonymized.getValue()).isEqualTo(originalVal);
+    }
+
+
     @Test
     public void call_apply_with_mapping_failure() {
+        final PseudoFuncConfig config = getConfig();
+        config.add(MapFuncConfig.Param.MAP_FAILURE_STRATEGY, MapFailureStrategy.RETURN_NULL);
         PseudoFunc func = PseudoFuncFactory.create(config);
 
-        assertThrows(MappingNotFoundException.class,() ->
-            func.apply(PseudoFuncInput.of("unknown"))
-        );
+        assertThat(func.apply(PseudoFuncInput.of("unknown")).getValue()).isNull();
     }
 
     @Test
     public void call_restore_with_mapping_failure() {
+        final PseudoFuncConfig config = getConfig();
+        config.add(MapFuncConfig.Param.MAP_FAILURE_STRATEGY, MapFailureStrategy.RETURN_NULL);
         PseudoFunc func = PseudoFuncFactory.create(config);
 
-        assertThrows(MappingNotFoundException.class,() ->
-                func.restore(PseudoFuncInput.of("unknown"))
-        );
+        assertThat(func.restore(PseudoFuncInput.of("unknown")).getValue()).isNull();
     }
 
 }
diff --git a/src/test/java/no/ssb/dapla/dlp/pseudo/func/map/MapFuncTest.java b/src/test/java/no/ssb/dapla/dlp/pseudo/func/map/MapFuncTest.java
@@ -26,4 +26,28 @@ public void transformAndRestore() {
         assertThat(depseudonymized.getValue()).isEqualTo(TestMapper.ORIGINAL);
     }
 
+    @Test
+    public void testInvalidMappingStrategyIgnore() {
+        final PseudoFuncConfig config = new PseudoFuncConfig(ImmutableMap.of(
+                PseudoFuncConfig.Param.FUNC_DECL, "map-test",
+                PseudoFuncConfig.Param.FUNC_IMPL, MapFunc.class.getName(),
+                MapFuncConfig.Param.MAP_FAILURE_STRATEGY, MapFailureStrategy.RETURN_ORIGINAL
+        ));
+        PseudoFunc func = PseudoFuncFactory.create(config);
+
+        PseudoFuncOutput mapOutput = func.apply(PseudoFuncInput.of("nomappingavailable"));
+        assertThat(mapOutput.getValue()).isEqualTo("nomappingavailable");
+    }
+
+    @Test
+    public void testInvalidMappingStrategyAbort() {
+        final PseudoFuncConfig config = new PseudoFuncConfig(ImmutableMap.of(
+                PseudoFuncConfig.Param.FUNC_DECL, "map-test",
+                PseudoFuncConfig.Param.FUNC_IMPL, MapFunc.class.getName(),
+                MapFuncConfig.Param.MAP_FAILURE_STRATEGY, MapFailureStrategy.RETURN_NULL
+        ));
+        PseudoFunc func = PseudoFuncFactory.create(config);
+
+        assertThat(func.apply(PseudoFuncInput.of("unknown")).getValue()).isNull();
+    }
 }
diff --git a/src/test/java/no/ssb/dapla/dlp/pseudo/func/map/TestMapper.java b/src/test/java/no/ssb/dapla/dlp/pseudo/func/map/TestMapper.java
@@ -4,6 +4,7 @@
 import no.ssb.dapla.dlp.pseudo.func.PseudoFuncOutput;
 
 import java.util.Map;
+import java.util.Optional;
 
 /**
  * This class is loaded using the Java Service Provider API.
@@ -12,30 +13,38 @@ public class TestMapper implements Mapper {
 
     public static String ORIGINAL = "OriginalValue";
     public static String MAPPED = "MappedValue";
+    private MapFailureStrategy mapFailureStrategy = MapFailureStrategy.RETURN_ORIGINAL;
 
     @Override
     public void init(PseudoFuncInput data) {
     }
 
     @Override
     public void setConfig(Map<String, Object> config) {
+        this.mapFailureStrategy = Optional.ofNullable(
+                config.getOrDefault(MapFuncConfig.Param.MAP_FAILURE_STRATEGY, null)
+        ).map(String::valueOf).map(MapFailureStrategy::valueOf).orElse(MapFailureStrategy.RETURN_ORIGINAL);
     }
 
     @Override
-    public PseudoFuncOutput map(PseudoFuncInput input) throws MappingNotFoundException {
+    public PseudoFuncOutput map(PseudoFuncInput input) {
         if (ORIGINAL.equals(input.value())) {
             return PseudoFuncOutput.of(MAPPED);
+        } else if (mapFailureStrategy == MapFailureStrategy.RETURN_ORIGINAL) {
+            return PseudoFuncOutput.of(input.value());
         } else {
-            throw new MappingNotFoundException(String.format("Could not map value %s", input.value()));
+            return PseudoFuncOutput.of(null);
         }
     }
 
     @Override
-    public PseudoFuncOutput restore(PseudoFuncInput mapped) throws MappingNotFoundException {
+    public PseudoFuncOutput restore(PseudoFuncInput mapped) {
         if (MAPPED.equals(mapped.value())) {
             return PseudoFuncOutput.of(ORIGINAL);
+        } else if (mapFailureStrategy == MapFailureStrategy.RETURN_ORIGINAL) {
+            return PseudoFuncOutput.of(mapped.value());
         } else {
-            throw new MappingNotFoundException(String.format("Could not map value %s", mapped.value()));
+            return PseudoFuncOutput.of(null);
         }
     }
 }