Add basic InMemoryFlagSource

1 files changed, 34 insertions, 0 deletions

diff --git a/flags/src/main/java/com/yahoo/vespa/flags/InMemoryFlagSource.java b/flags/src/main/java/com/yahoo/vespa/flags/InMemoryFlagSource.java
new file mode 100644
index 00000000000..25b871f8cd1
--- /dev/null
+++ b/flags/src/main/java/com/yahoo/vespa/flags/InMemoryFlagSource.java
@@ -0,0 +1,34 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.flags;
+
+import com.yahoo.vespa.flags.json.FlagData;
+import com.yahoo.vespa.flags.json.Rule;
+
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Basic in-memory flag source useful for testing
+ *
+ * @author freva
+ */
+public class InMemoryFlagSource implements FlagSource {
+    private final Map<FlagId, FlagData> flagDataById = new ConcurrentHashMap<>();
+
+    public InMemoryFlagSource withFlag(FlagId flagId) {
+        flagDataById.put(flagId, new FlagData(flagId));
+        return this;
+    }
+
+    public InMemoryFlagSource withFlag(FlagId flagId, FetchVector defaultFetchVector, Rule... rules) {
+        flagDataById.put(flagId, new FlagData(flagId, defaultFetchVector, rules));
+        return this;
+    }
+
+    @Override
+    public Optional<RawFlag> fetch(FlagId id, FetchVector vector) {
+        return Optional.ofNullable(flagDataById.get(id))
+                .flatMap(flagData -> flagData.resolve(vector));
+    }
+}