FT Sanitizer

src/main/java/io/split/android/client/fallback/FallbackConfiguration.java

@@ -0,0 +1,103 @@
+package io.split.android.client.fallback;
+
+import androidx.annotation.Nullable;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+
+public final class FallbackConfiguration {
+
+    @Nullable
+    private final FallbackTreatment mGlobal;
+    private final Map<String, FallbackTreatment> mByFlag;
+
+    private FallbackConfiguration(@Nullable FallbackTreatment global,
+                                  @Nullable Map<String, FallbackTreatment> byFlag) {
+        mGlobal = global;
+        if (byFlag == null || byFlag.isEmpty()) {
+            mByFlag = Collections.emptyMap();
+        } else {
+            mByFlag = Collections.unmodifiableMap(new HashMap<>(byFlag));
+        }
+    }
+
+    @Nullable
+    public FallbackTreatment getGlobal() {
+        return mGlobal;
+    }
+
+    public Map<String, FallbackTreatment> getByFlag() {
+        return mByFlag;
+    }
+
+    /**
+     * Creates a new {@link Builder} for {@link FallbackConfiguration}.
+     * Use this to provide an optional global fallback and flag-specific fallbacks.
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+        @Nullable
+        private FallbackTreatment mGlobal;
+        @Nullable
+        private Map<String, FallbackTreatment> mByFlag;
+
+        private Builder() {
+            mGlobal = null;
+            mByFlag = null;
+        }
+
+        /**
+         * Sets an optional global fallback treatment to be used when no flag-specific
+         * fallback exists for a given flag. This value is returned only in place of
+         * the "control" treatment.
+         *
+         * @param global optional global {@link FallbackTreatment}
+         * @return this builder instance
+         */
+        public Builder global(@Nullable FallbackTreatment global) {
+            mGlobal = global;
+            return this;
+        }
+
+        /**
+         * Sets optional flag-specific fallback treatments, where keys are flag names.
+         * These take precedence over the global fallback.
+         *
+         * @param byFlag map of flag name to {@link FallbackTreatment}; may be null or empty
+         * @return this builder instance
+         */
+        public Builder byFlag(@Nullable Map<String, FallbackTreatment> byFlag) {
+            mByFlag = byFlag;
+            return this;
+        }
+
+        /**
+         * Builds an immutable {@link FallbackConfiguration} snapshot of the
+         * configured values.
+         *
+         * @return a new immutable {@link FallbackConfiguration}
+         */
+        public FallbackConfiguration build() {
+            return new FallbackConfiguration(mGlobal, mByFlag);
+        }
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        FallbackConfiguration that = (FallbackConfiguration) o;
+        return Objects.equals(mGlobal, that.mGlobal) &&
+                Objects.equals(mByFlag, that.mByFlag);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mGlobal, mByFlag);
+    }
+}

src/main/java/io/split/android/client/fallback/FallbackTreatment.java

@@ -0,0 +1,55 @@
+package io.split.android.client.fallback;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import java.util.Objects;
+
+/**
+ * Represents the fallback treatment, with an optional config and a fixed label.
+ */
+public final class FallbackTreatment {
+
+    public static final String LABEL = "fallback treatment";
+
+    @NonNull
+    private final String mTreatment;
+    @Nullable
+    private final String mConfig;
+
+    public FallbackTreatment(@NonNull String treatment) {
+        this(treatment, null);
+    }
+
+    public FallbackTreatment(@NonNull String treatment, @Nullable String config) {
+        mTreatment = treatment;
+        mConfig = config;
+    }
+
+    public String getTreatment() {
+        return mTreatment;
+    }
+
+    @Nullable
+    public String getConfig() {
+        return mConfig;
+    }
+
+    public String getLabel() {
+        return LABEL;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        FallbackTreatment that = (FallbackTreatment) o;
+        return Objects.equals(mTreatment, that.mTreatment) &&
+                Objects.equals(mConfig, that.mConfig);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mTreatment, mConfig);
+    }
+}

src/main/java/io/split/android/client/fallback/FallbackTreatmentsConfiguration.java

@@ -0,0 +1,51 @@
+package io.split.android.client.fallback;
+
+import androidx.annotation.Nullable;
+import androidx.annotation.VisibleForTesting;
+
+public final class FallbackTreatmentsConfiguration {
+
+    @Nullable
+    private final FallbackConfiguration mByFactory;
+
+    private FallbackTreatmentsConfiguration(@Nullable FallbackConfiguration byFactory) {
+        mByFactory = byFactory;
+    }
+
+    @Nullable
+    public FallbackConfiguration getByFactory() {
+        return mByFactory;
+    }
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+        @Nullable
+        private FallbackConfiguration mByFactory;
+        private FallbacksSanitizer mSanitizer;
+
+        private Builder() {
+            mSanitizer = new FallbacksSanitizerImpl();
+        }
+
+        @VisibleForTesting
+        Builder sanitizer(FallbacksSanitizer sanitizer) {
+            mSanitizer = sanitizer;
+            return this;
+        }
+
+        public Builder byFactory(@Nullable FallbackConfiguration byFactory) {
+            mByFactory = byFactory;
+            return this;
+        }
+
+        public FallbackTreatmentsConfiguration build() {
+            FallbackConfiguration sanitized = (mByFactory == null)
+                    ? null
+                    : mSanitizer.sanitize(mByFactory);
+            return new FallbackTreatmentsConfiguration(sanitized);
+        }
+    }
+}

src/main/java/io/split/android/client/fallback/FallbacksSanitizer.java

@@ -0,0 +1,9 @@
+package io.split.android.client.fallback;
+
+import androidx.annotation.Nullable;
+
+interface FallbacksSanitizer {
+
+    @Nullable
+    FallbackConfiguration sanitize(@Nullable FallbackConfiguration config);
+}

src/main/java/io/split/android/client/fallback/FallbacksSanitizerImpl.java

@@ -0,0 +1,98 @@
+package io.split.android.client.fallback;
+
+import androidx.annotation.Nullable;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import io.split.android.client.utils.logger.Logger;
+
+/**
+ * Validates and sanitizes fallback configurations by applying validation rules.
+ * Invalid entries are dropped and warnings are logged.
+ */
+class FallbacksSanitizerImpl implements FallbacksSanitizer {
+
+    private static final int MAX_FLAG_NAME_LENGTH = 100;
+    private static final int MAX_TREATMENT_LENGTH = 100;
+
+    /**
+     * Sanitizes the provided fallback configuration by applying validation rules.
+     * Invalid entries are dropped and warnings are logged.
+     *
+     * @param config the configuration to sanitize; may be null
+     * @return a new sanitized configuration, or null if input was null
+     */
+    @Nullable
+    public FallbackConfiguration sanitize(@Nullable FallbackConfiguration config) {
+        if (config == null) {
+            return null;
+        }
+
+        // Sanitize global treatment
+        FallbackTreatment sanitizedGlobal = sanitizeGlobalTreatment(config.getGlobal());
+
+        // Sanitize by-flag treatments
+        Map<String, FallbackTreatment> sanitizedByFlag = sanitizeByFlagTreatments(config.getByFlag());
+
+        return FallbackConfiguration.builder()
+                .global(sanitizedGlobal)
+                .byFlag(sanitizedByFlag)
+                .build();
+    }
+
+    @Nullable
+    private FallbackTreatment sanitizeGlobalTreatment(@Nullable FallbackTreatment global) {
+        if (global == null) {
+            return null;
+        }
+
+        if (!isValidTreatment(global)) {
+            Logger.w("Discarded global fallback: Invalid treatment (max " + MAX_TREATMENT_LENGTH + " chars)");
+            return null;
+        }
+
+        return global;
+    }
+
+    private Map<String, FallbackTreatment> sanitizeByFlagTreatments(Map<String, FallbackTreatment> byFlag) {
+        if (byFlag == null || byFlag.isEmpty()) {
+            return new HashMap<>();
+        }
+
+        Map<String, FallbackTreatment> sanitized = new HashMap<>();
+
+        for (Map.Entry<String, FallbackTreatment> entry : byFlag.entrySet()) {
+            String flagName = entry.getKey();
+            FallbackTreatment treatment = entry.getValue();
+
+            if (!isValidFlagName(flagName)) {
+                Logger.w("Discarded flag '" + flagName + "': Invalid flag name (max " + MAX_FLAG_NAME_LENGTH + " chars, no spaces)");
+                continue;
+            }
+
+            if (!isValidTreatment(treatment)) {
+                Logger.w("Discarded treatment for flag '" + flagName + "': Invalid treatment (max " + MAX_TREATMENT_LENGTH + " chars)");
+                continue;
+            }
+
+            sanitized.put(flagName, treatment);
+        }
+
+        return sanitized;
+    }
+
+    private static boolean isValidFlagName(String flagName) {
+        if (flagName == null) {
+            return false;
+        }
+        return flagName.length() <= MAX_FLAG_NAME_LENGTH && !flagName.contains(" ");
+    }
+
+    private static boolean isValidTreatment(FallbackTreatment treatment) {
+        if (treatment == null || treatment.getTreatment() == null) {
+            return false;
+        }
+        return treatment.getTreatment().length() <= MAX_TREATMENT_LENGTH;
+    }
+}

src/test/java/io/split/android/client/fallback/FallbackConfigurationTest.java

@@ -0,0 +1,72 @@
+package io.split.android.client.fallback;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertSame;
+
+import org.junit.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class FallbackConfigurationTest {
+
+    @Test
+    public void constructorSetsFields() {
+        FallbackTreatment global = new FallbackTreatment("off");
+        Map<String, FallbackTreatment> map = new HashMap<>();
+        map.put("flagA", new FallbackTreatment("off"));
+
+        FallbackConfiguration cfg = FallbackConfiguration.builder()
+                .global(global)
+                .byFlag(map)
+                .build();
+
+        assertSame(global, cfg.getGlobal());
+        assertEquals(1, cfg.getByFlag().size());
+        assertEquals("off", cfg.getByFlag().get("flagA").getTreatment());
+    }
+
+    @Test
+    public void byFlagIsUnmodifiable() {
+        FallbackTreatment global = new FallbackTreatment("off");
+        Map<String, FallbackTreatment> byFlag = new HashMap<>();
+        byFlag.put("flagA", new FallbackTreatment("off"));
+
+        FallbackConfiguration config = FallbackConfiguration.builder()
+                .global(global)
+                .byFlag(byFlag)
+                .build();
+
+        byFlag.put("flagB", new FallbackTreatment("on"));
+
+        // config map must not change
+        assertEquals(1, config.getByFlag().size());
+
+        try {
+            config.getByFlag().put("x", new FallbackTreatment("on"));
+            throw new AssertionError("Map should be unmodifiable");
+        } catch (UnsupportedOperationException expected) {
+
+        }
+    }
+
+    @Test
+    public void equalityAndHashCodeByValue() {
+        FallbackTreatment global = new FallbackTreatment("off");
+        Map<String, FallbackTreatment> a = new HashMap<>();
+        a.put("flagA", new FallbackTreatment("off"));
+
+        Map<String, FallbackTreatment> b = new HashMap<>();
+        b.put("flagA", new FallbackTreatment("off"));
+
+        FallbackConfiguration configOne = FallbackConfiguration.builder().global(global).byFlag(a).build();
+        FallbackConfiguration configTwo = FallbackConfiguration.builder().global(global).byFlag(b).build();
+        FallbackConfiguration configThree = FallbackConfiguration.builder().global(null).byFlag(b).build();
+
+        assertEquals(configOne, configTwo);
+        assertEquals(configOne.hashCode(), configTwo.hashCode());
+        assertNotEquals(configOne, configThree);
+        assertNotEquals(configOne.hashCode(), configThree.hashCode());
+    }
+}