Revert "Decouple flags REST API from config server"

This reverts commit b81b21546cdff92d360cbdf7dda27e6ed7bc7170.

9 files changed, 561 insertions, 1 deletions

diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/DefinedFlag.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/DefinedFlag.java
new file mode 100644
index 00000000000..92397fc84a7
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/DefinedFlag.java
@@ -0,0 +1,47 @@
+// Copyright 2019 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.yahoo.container.jdisc.HttpResponse;
+import com.yahoo.jdisc.Response;
+import com.yahoo.vespa.config.server.http.HttpConfigResponse;
+import com.yahoo.vespa.flags.FlagDefinition;
+import com.yahoo.vespa.flags.json.DimensionHelper;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ * @author hakonhall
+ */
+public class DefinedFlag extends HttpResponse {
+    private static ObjectMapper mapper = new ObjectMapper();
+
+    private final FlagDefinition flagDefinition;
+
+    public DefinedFlag(FlagDefinition flagDefinition) {
+        super(Response.Status.OK);
+        this.flagDefinition = flagDefinition;
+    }
+
+    @Override
+    public void render(OutputStream outputStream) throws IOException {
+        ObjectNode rootNode = mapper.createObjectNode();
+        renderFlagDefinition(flagDefinition, rootNode);
+        mapper.writeValue(outputStream, rootNode);
+    }
+
+    static void renderFlagDefinition(FlagDefinition flagDefinition, ObjectNode definitionNode) {
+        definitionNode.put("description", flagDefinition.getDescription());
+        definitionNode.put("modification-effect", flagDefinition.getModificationEffect());
+        ArrayNode dimensionsNode = definitionNode.putArray("dimensions");
+        flagDefinition.getDimensions().forEach(dimension -> dimensionsNode.add(DimensionHelper.toWire(dimension)));
+    }
+
+    @Override
+    public String getContentType() {
+        return HttpConfigResponse.JSON_CONTENT_TYPE;
+    }
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/DefinedFlags.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/DefinedFlags.java
new file mode 100644
index 00000000000..9604c51ee4b
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/DefinedFlags.java
@@ -0,0 +1,45 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.yahoo.container.jdisc.HttpResponse;
+import com.yahoo.jdisc.Response;
+import com.yahoo.vespa.config.server.http.HttpConfigResponse;
+import com.yahoo.vespa.flags.FlagDefinition;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.Comparator;
+import java.util.List;
+
+/**
+ * @author hakonhall
+ */
+public class DefinedFlags extends HttpResponse {
+    private static ObjectMapper mapper = new ObjectMapper();
+    private static final Comparator<FlagDefinition> sortByFlagId =
+            (left, right) -> left.getUnboundFlag().id().compareTo(right.getUnboundFlag().id());
+
+    private final List<FlagDefinition> flags;
+
+    public DefinedFlags(List<FlagDefinition> flags) {
+        super(Response.Status.OK);
+        this.flags = flags;
+    }
+
+    @Override
+    public void render(OutputStream outputStream) throws IOException {
+        ObjectNode rootNode = mapper.createObjectNode();
+        flags.stream().sorted(sortByFlagId).forEach(flagDefinition -> {
+            ObjectNode definitionNode = rootNode.putObject(flagDefinition.getUnboundFlag().id().toString());
+            DefinedFlag.renderFlagDefinition(flagDefinition, definitionNode);
+        });
+        mapper.writeValue(outputStream, rootNode);
+    }
+
+    @Override
+    public String getContentType() {
+        return HttpConfigResponse.JSON_CONTENT_TYPE;
+    }
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagDataListResponse.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagDataListResponse.java
new file mode 100644
index 00000000000..b33fc7c2b04
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagDataListResponse.java
@@ -0,0 +1,59 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.yahoo.container.jdisc.HttpResponse;
+import com.yahoo.jdisc.Response;
+import com.yahoo.vespa.config.server.http.HttpConfigResponse;
+import com.yahoo.vespa.flags.FlagId;
+import com.yahoo.vespa.flags.json.FlagData;
+import com.yahoo.vespa.flags.json.wire.WireFlagDataList;
+
+import java.io.OutputStream;
+import java.util.Map;
+import java.util.TreeMap;
+
+import static com.yahoo.yolean.Exceptions.uncheck;
+
+/**
+ * @author hakonhall
+ */
+public class FlagDataListResponse extends HttpResponse {
+    private static ObjectMapper mapper = new ObjectMapper();
+
+    private final String flagsV1Uri;
+    private final TreeMap<FlagId, FlagData> flags;
+    private final boolean recursive;
+
+    public FlagDataListResponse(String flagsV1Uri, Map<FlagId, FlagData> flags, boolean recursive) {
+        super(Response.Status.OK);
+        this.flagsV1Uri = flagsV1Uri;
+        this.flags = new TreeMap<>(flags);
+        this.recursive = recursive;
+    }
+
+    @Override
+    public void render(OutputStream outputStream) {
+        if (recursive) {
+            WireFlagDataList list = new WireFlagDataList();
+            flags.values().forEach(flagData -> list.flags.add(flagData.toWire()));
+            list.serializeToOutputStream(outputStream);
+        } else {
+            ObjectNode rootNode = mapper.createObjectNode();
+            ArrayNode flagsArray = rootNode.putArray("flags");
+            flags.forEach((flagId, flagData) -> {
+                ObjectNode object = flagsArray.addObject();
+                object.put("id", flagId.toString());
+                object.put("url", flagsV1Uri + "/data/" + flagId.toString());
+            });
+            uncheck(() -> mapper.writeValue(outputStream, rootNode));
+        }
+    }
+
+    @Override
+    public String getContentType() {
+        return HttpConfigResponse.JSON_CONTENT_TYPE;
+    }
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagDataResponse.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagDataResponse.java
new file mode 100644
index 00000000000..054b218ff2d
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagDataResponse.java
@@ -0,0 +1,31 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.yahoo.container.jdisc.HttpResponse;
+import com.yahoo.jdisc.Response;
+import com.yahoo.vespa.config.server.http.HttpConfigResponse;
+import com.yahoo.vespa.flags.json.FlagData;
+
+import java.io.OutputStream;
+
+/**
+ * @author hakonhall
+ */
+public class FlagDataResponse extends HttpResponse {
+    private final FlagData data;
+
+    FlagDataResponse(FlagData data) {
+        super(Response.Status.OK);
+        this.data = data;
+    }
+
+    @Override
+    public void render(OutputStream outputStream) {
+        data.serializeToOutputStream(outputStream);
+    }
+
+    @Override
+    public String getContentType() {
+        return HttpConfigResponse.JSON_CONTENT_TYPE;
+    }
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagsHandler.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagsHandler.java
new file mode 100644
index 00000000000..00f3d457d3d
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/FlagsHandler.java
@@ -0,0 +1,120 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.google.inject.Inject;
+import com.yahoo.container.jdisc.HttpRequest;
+import com.yahoo.container.jdisc.HttpResponse;
+import com.yahoo.container.jdisc.LoggingRequestHandler;
+import com.yahoo.restapi.Path;
+import com.yahoo.vespa.config.server.http.HttpErrorResponse;
+import com.yahoo.vespa.config.server.http.HttpHandler;
+import com.yahoo.vespa.config.server.http.NotFoundException;
+import com.yahoo.vespa.configserver.flags.FlagsDb;
+import com.yahoo.vespa.flags.FlagDefinition;
+import com.yahoo.vespa.flags.FlagId;
+import com.yahoo.vespa.flags.Flags;
+import com.yahoo.vespa.flags.json.FlagData;
+import com.yahoo.yolean.Exceptions;
+
+import java.io.UncheckedIOException;
+import java.net.URI;
+import java.util.Objects;
+
+/**
+ * Handles /flags/v1 requests
+ *
+ * @author hakonhall
+ */
+public class FlagsHandler extends HttpHandler {
+    private final FlagsDb flagsDb;
+
+    @Inject
+    public FlagsHandler(LoggingRequestHandler.Context context, FlagsDb flagsDb) {
+        super(context);
+        this.flagsDb = flagsDb;
+    }
+
+    @Override
+    protected HttpResponse handleGET(HttpRequest request) {
+        Path path = new Path(request.getUri());
+        if (path.matches("/flags/v1")) return new V1Response(flagsV1Uri(request), "data", "defined");
+        if (path.matches("/flags/v1/data")) return getFlagDataList(request);
+        if (path.matches("/flags/v1/data/{flagId}")) return getFlagData(findFlagId(request, path));
+        if (path.matches("/flags/v1/defined")) return new DefinedFlags(Flags.getAllFlags());
+        if (path.matches("/flags/v1/defined/{flagId}")) return getDefinedFlag(findFlagId(request, path));
+        throw new NotFoundException("Nothing at path '" + path + "'");
+    }
+
+    @Override
+    protected HttpResponse handlePUT(HttpRequest request) {
+        Path path = new Path(request.getUri());
+        if (path.matches("/flags/v1/data/{flagId}")) return putFlagData(request, findFlagId(request, path));
+        throw new NotFoundException("Nothing at path '" + path + "'");
+    }
+
+    @Override
+    protected HttpResponse handleDELETE(HttpRequest request) {
+        Path path = new Path(request.getUri());
+        if (path.matches("/flags/v1/data/{flagId}")) return deleteFlagData(findFlagId(request, path));
+        throw new NotFoundException("Nothing at path '" + path + "'");
+    }
+
+    private String flagsV1Uri(HttpRequest request) {
+        URI uri = request.getUri();
+        String port = uri.getPort() < 0 ? "" : ":" + uri.getPort();
+        return uri.getScheme() + "://" + uri.getHost() + port + "/flags/v1";
+    }
+
+    private HttpResponse getDefinedFlag(FlagId flagId) {
+        FlagDefinition definition = Flags.getFlag(flagId)
+                .orElseThrow(() -> new NotFoundException("Flag " + flagId + " not defined"));
+        return new DefinedFlag(definition);
+    }
+
+    private HttpResponse getFlagDataList(HttpRequest request) {
+        return new FlagDataListResponse(flagsV1Uri(request), flagsDb.getAllFlags(),
+                Objects.equals(request.getProperty("recursive"), "true"));
+    }
+
+    private HttpResponse getFlagData(FlagId flagId) {
+        FlagData data = flagsDb.getValue(flagId).orElseThrow(() -> new NotFoundException("Flag " + flagId + " not set"));
+        return new FlagDataResponse(data);
+    }
+
+    private HttpResponse putFlagData(HttpRequest request, FlagId flagId) {
+        FlagData data;
+        try {
+            data = FlagData.deserialize(request.getData());
+        } catch (UncheckedIOException e) {
+            return HttpErrorResponse.badRequest("Failed to deserialize request data: " + Exceptions.toMessageString(e));
+        }
+
+        if (!isForce(request)) {
+            FlagDefinition definition = Flags.getFlag(flagId).get(); // FlagId has been validated in findFlagId()
+            data.validate(definition.getUnboundFlag().serializer());
+        }
+
+        flagsDb.setValue(flagId, data);
+        return new OKResponse();
+    }
+
+    private HttpResponse deleteFlagData(FlagId flagId) {
+        flagsDb.removeValue(flagId);
+        return new OKResponse();
+    }
+
+    private FlagId findFlagId(HttpRequest request, Path path) {
+        FlagId flagId = new FlagId(path.get("flagId"));
+
+        if (!isForce(request)) {
+            Flags.getFlag(flagId).orElseThrow(() ->
+                    new NotFoundException("There is no flag '" + flagId + "' (use ?force=true to override)"));
+        }
+
+        return flagId;
+    }
+
+    private boolean isForce(HttpRequest request) {
+        return Objects.equals(request.getProperty("force"), "true");
+    }
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/OKResponse.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/OKResponse.java
new file mode 100644
index 00000000000..87c02ae56f1
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/OKResponse.java
@@ -0,0 +1,20 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.yahoo.container.jdisc.EmptyResponse;
+import com.yahoo.jdisc.Response;
+import com.yahoo.vespa.config.server.http.HttpConfigResponse;
+
+/**
+ * @author hakonhall
+ */
+public class OKResponse extends EmptyResponse {
+    public OKResponse() {
+        super(Response.Status.OK);
+    }
+
+    @Override
+    public String getContentType() {
+        return HttpConfigResponse.JSON_CONTENT_TYPE;
+    }
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/V1Response.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/V1Response.java
new file mode 100644
index 00000000000..3594c801ca8
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/flags/V1Response.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.config.server.http.flags;
+
+import com.yahoo.jdisc.Response;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.SlimeUtils;
+import com.yahoo.vespa.config.server.http.HttpConfigResponse;
+import com.yahoo.vespa.config.server.http.StaticResponse;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static com.yahoo.yolean.Exceptions.uncheck;
+
+/**
+ * @author hakonhall
+ */
+public class V1Response extends StaticResponse {
+    public V1Response(String flagsV1Uri, String... names) {
+        super(Response.Status.OK, HttpConfigResponse.JSON_CONTENT_TYPE, generateBody(flagsV1Uri, Arrays.asList(names)));
+    }
+
+    private static String generateBody(String flagsV1Uri, List<String> names) {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        names.forEach(name -> {
+            Cursor data = root.setObject(name);
+            data.setString("url", flagsV1Uri + "/" + name);
+        });
+        return Utf8.toString(uncheck(() -> SlimeUtils.toJsonBytes(slime)));
+    }
+}
diff --git a/configserver/src/main/resources/configserver-app/services.xml b/configserver/src/main/resources/configserver-app/services.xml
index b429e220c33..cfacd6ff8c9 100644
--- a/configserver/src/main/resources/configserver-app/services.xml
+++ b/configserver/src/main/resources/configserver-app/services.xml
@@ -54,7 +54,7 @@
     <preprocess:include file='model-integration.xml' required='true' />
 
     <component id="com.yahoo.vespa.configserver.flags.ConfigServerFlagSource" bundle="configserver-flags"/>
-    <component id="com.yahoo.vespa.flags.persistence.FlagsDb" bundle="flags"/>
+    <component id="com.yahoo.vespa.configserver.flags.db.FlagsDbImpl" bundle="configserver-flags"/>
 
     <preprocess:include file='metrics-packets.xml' required='false' />
     <preprocess:include file='container.xml' required='false' />
@@ -92,6 +92,10 @@
     <handler id='com.yahoo.vespa.config.server.http.status.StatusHandler' bundle='configserver'>
       <binding>http://*/status</binding>
     </handler>
+    <handler id='com.yahoo.vespa.config.server.http.flags.FlagsHandler' bundle='configserver'>
+      <binding>http://*/flags/v1</binding>
+      <binding>http://*/flags/v1/*</binding>
+    </handler>
     <handler id='com.yahoo.vespa.config.server.http.v2.TenantHandler' bundle='configserver'>
       <binding>http://*/application/v2/tenant/</binding>
       <binding>http://*/application/v2/tenant/*</binding>
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/http/flags/FlagsHandlerTest.java b/configserver/src/test/java/com/yahoo/vespa/config/server/http/flags/FlagsHandlerTest.java
new file mode 100644
index 00000000000..5ae6ce9820b
--- /dev/null
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/http/flags/FlagsHandlerTest.java
@@ -0,0 +1,200 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.server.http.flags;
+
+import com.yahoo.container.jdisc.HttpRequest;
+import com.yahoo.container.jdisc.HttpResponse;
+import com.yahoo.jdisc.http.HttpRequest.Method;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.server.http.SessionHandlerTest;
+import com.yahoo.vespa.configserver.flags.db.FlagsDbImpl;
+import com.yahoo.vespa.curator.mock.MockCurator;
+import com.yahoo.vespa.flags.FetchVector;
+import com.yahoo.vespa.flags.FlagId;
+import com.yahoo.vespa.flags.Flags;
+import com.yahoo.vespa.flags.UnboundBooleanFlag;
+import org.junit.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static com.yahoo.yolean.Exceptions.uncheck;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertEquals;
+
+/**
+ * @author hakonhall
+ */
+public class FlagsHandlerTest {
+    private static final UnboundBooleanFlag FLAG1 = Flags.defineFeatureFlag(
+            "id1", false, "desc1", "mod1");
+    private static final UnboundBooleanFlag FLAG2 = Flags.defineFeatureFlag(
+            "id2", true, "desc2", "mod2",
+            FetchVector.Dimension.HOSTNAME, FetchVector.Dimension.APPLICATION_ID);
+
+    private static final String FLAGS_V1_URL = "https://foo.com:4443/flags/v1";
+
+    private final FlagsDbImpl flagsDb = new FlagsDbImpl(new MockCurator());
+    private final FlagsHandler handler = new FlagsHandler(FlagsHandler.testOnlyContext(), flagsDb);
+
+    @Test
+    public void testV1() {
+        String expectedResponse = "{" +
+                Stream.of("data", "defined")
+                        .map(name -> "\"" + name + "\":{\"url\":\"https://foo.com:4443/flags/v1/" + name + "\"}")
+                        .collect(Collectors.joining(",")) +
+                "}";
+        verifySuccessfulRequest(Method.GET, "", "", expectedResponse);
+        verifySuccessfulRequest(Method.GET, "/", "", expectedResponse);
+    }
+
+    @Test
+    public void testDefined() {
+        try (Flags.Replacer replacer = Flags.clearFlagsForTesting()) {
+            fixUnusedWarning(replacer);
+            Flags.defineFeatureFlag("id", false, "desc", "mod", FetchVector.Dimension.HOSTNAME);
+            verifySuccessfulRequest(Method.GET, "/defined", "",
+                    "{\"id\":{\"description\":\"desc\",\"modification-effect\":\"mod\",\"dimensions\":[\"hostname\"]}}");
+
+            verifySuccessfulRequest(Method.GET, "/defined/id", "",
+                    "{\"description\":\"desc\",\"modification-effect\":\"mod\",\"dimensions\":[\"hostname\"]}");
+        }
+    }
+
+    private void fixUnusedWarning(Flags.Replacer replacer) { }
+
+    @Test
+    public void testData() {
+        // PUT flag with ID id1
+        verifySuccessfulRequest(Method.PUT, "/data/" + FLAG1.id(),
+                "{\n" +
+                        "  \"id\": \"id1\",\n" +
+                        "  \"rules\": [\n" +
+                        "    {\n" +
+                        "      \"value\": true\n" +
+                        "    }\n" +
+                        "  ]\n" +
+                        "}",
+                "");
+
+        // GET on ID id1 should return the same as the put.
+        verifySuccessfulRequest(Method.GET, "/data/" + FLAG1.id(),
+                "", "{\"id\":\"id1\",\"rules\":[{\"value\":true}]}");
+
+        // List all flags should list only id1
+        verifySuccessfulRequest(Method.GET, "/data",
+                "", "{\"flags\":[{\"id\":\"id1\",\"url\":\"https://foo.com:4443/flags/v1/data/id1\"}]}");
+
+        // Should be identical to above: suffix / on path should be ignored
+        verifySuccessfulRequest(Method.GET, "/data/",
+                "", "{\"flags\":[{\"id\":\"id1\",\"url\":\"https://foo.com:4443/flags/v1/data/id1\"}]}");
+
+        // Verify absent port => absent in response
+        assertThat(handleWithPort(Method.GET, -1, "/data", "", 200),
+                is("{\"flags\":[{\"id\":\"id1\",\"url\":\"https://foo.com/flags/v1/data/id1\"}]}"));
+
+        // PUT id2
+        verifySuccessfulRequest(Method.PUT, "/data/" + FLAG2.id(),
+                "{\n" +
+                        "  \"id\": \"id2\",\n" +
+                        "  \"rules\": [\n" +
+                        "    {\n" +
+                        "      \"conditions\": [\n" +
+                        "        {\n" +
+                        "          \"type\": \"whitelist\",\n" +
+                        "          \"dimension\": \"hostname\",\n" +
+                        "          \"values\": [ \"host1\", \"host2\" ]\n" +
+                        "        },\n" +
+                        "        {\n" +
+                        "          \"type\": \"blacklist\",\n" +
+                        "          \"dimension\": \"application\",\n" +
+                        "          \"values\": [ \"app1\", \"app2\" ]\n" +
+                        "        }\n" +
+                        "      ],\n" +
+                        "      \"value\": true\n" +
+                        "    }\n" +
+                        "  ],\n" +
+                        "  \"attributes\": {\n" +
+                        "    \"zone\": \"zone1\"\n" +
+                        "  }\n" +
+                        "}\n",
+                "");
+
+        // GET on id2 should now return what was put
+        verifySuccessfulRequest(Method.GET, "/data/" + FLAG2.id(), "",
+                "{\"id\":\"id2\",\"rules\":[{\"conditions\":[{\"type\":\"whitelist\",\"dimension\":\"hostname\",\"values\":[\"host1\",\"host2\"]},{\"type\":\"blacklist\",\"dimension\":\"application\",\"values\":[\"app1\",\"app2\"]}],\"value\":true}],\"attributes\":{\"zone\":\"zone1\"}}");
+
+        // The list of flag data should return id1 and id2
+        verifySuccessfulRequest(Method.GET, "/data",
+                "",
+                "{\"flags\":[{\"id\":\"id1\",\"url\":\"https://foo.com:4443/flags/v1/data/id1\"},{\"id\":\"id2\",\"url\":\"https://foo.com:4443/flags/v1/data/id2\"}]}");
+
+        // Putting (overriding) id1 should work silently
+        verifySuccessfulRequest(Method.PUT, "/data/" + FLAG1.id(),
+                "{\n" +
+                        "  \"id\": \"id1\",\n" +
+                        "  \"rules\": [\n" +
+                        "    {\n" +
+                        "      \"value\": false\n" +
+                        "    }\n" +
+                        "  ]\n" +
+                        "}\n",
+                "");
+
+        // Verify PUT
+        verifySuccessfulRequest(Method.GET, "/data/" + FLAG1.id(), "", "{\"id\":\"id1\",\"rules\":[{\"value\":false}]}");
+
+        // Get all recursivelly displays all flag data
+        verifySuccessfulRequest(Method.GET, "/data?recursive=true", "",
+                "{\"flags\":[{\"id\":\"id1\",\"rules\":[{\"value\":false}]},{\"id\":\"id2\",\"rules\":[{\"conditions\":[{\"type\":\"whitelist\",\"dimension\":\"hostname\",\"values\":[\"host1\",\"host2\"]},{\"type\":\"blacklist\",\"dimension\":\"application\",\"values\":[\"app1\",\"app2\"]}],\"value\":true}],\"attributes\":{\"zone\":\"zone1\"}}]}");
+
+        // Deleting both flags
+        verifySuccessfulRequest(Method.DELETE, "/data/" + FLAG1.id(), "", "");
+        verifySuccessfulRequest(Method.DELETE, "/data/" + FLAG2.id(), "", "");
+
+        // And the list of data flags should now be empty
+        verifySuccessfulRequest(Method.GET, "/data", "", "{\"flags\":[]}");
+    }
+
+    @Test
+    public void testForcing() {
+        assertThat(handle(Method.PUT, "/data/" + new FlagId("undef"), "", 404),
+                containsString("There is no flag 'undef'"));
+
+        assertThat(handle(Method.PUT, "/data/" + new FlagId("undef") + "?force=true", "", 400),
+                containsString("No content to map due to end-of-input"));
+
+        assertThat(handle(Method.PUT, "/data/" + FLAG1.id(), "{}", 400),
+                containsString("Flag ID missing"));
+
+        assertThat(handle(Method.PUT, "/data/" + FLAG1.id(), "{\"id\": \"id1\",\"rules\": [{\"value\":\"string\"}]}", 400),
+                containsString("Wrong type of JsonNode: STRING"));
+
+        assertThat(handle(Method.PUT, "/data/" + FLAG1.id() + "?force=true", "{\"id\": \"id1\",\"rules\": [{\"value\":\"string\"}]}", 200),
+                is(""));
+    }
+
+    private void verifySuccessfulRequest(Method method, String pathSuffix, String requestBody, String expectedResponseBody) {
+        assertThat(handle(method, pathSuffix, requestBody, 200), is(expectedResponseBody));
+    }
+
+    private String handle(Method method, String pathSuffix, String requestBody, int expectedStatus) {
+        return handleWithPort(method, 4443, pathSuffix, requestBody, expectedStatus);
+    }
+
+    private String handleWithPort(Method method, int port, String pathSuffix, String requestBody, int expectedStatus) {
+        String uri = "https://foo.com" + (port < 0 ? "" : ":" + port) + "/flags/v1" + pathSuffix;
+        HttpRequest request = HttpRequest.createTestRequest(uri, method, makeInputStream(requestBody));
+        HttpResponse response = handler.handle(request);
+        assertEquals(expectedStatus, response.getStatus());
+        assertEquals("application/json", response.getContentType());
+        return uncheck(() -> SessionHandlerTest.getRenderedString(response));
+    }
+
+    private InputStream makeInputStream(String content) {
+        return new ByteArrayInputStream(Utf8.toBytes(content));
+    }
+}
\ No newline at end of file