Revert "Remove implicit and potensially false dependency on jdisc_http_service"

2 files changed, 201 insertions, 6 deletions

diff --git a/container-core/pom.xml b/container-core/pom.xml
index 68556c70e22..0fbb590a1de 100644
--- a/container-core/pom.xml
+++ b/container-core/pom.xml
@@ -101,12 +101,6 @@
     </dependency>
     <dependency>
       <groupId>com.yahoo.vespa</groupId>
-      <artifactId>jdisc_http_service</artifactId>
-      <version>${project.version}</version>
-      <scope>provided</scope>
-    </dependency>
-    <dependency>
-      <groupId>com.yahoo.vespa</groupId>
       <artifactId>linguistics</artifactId>
       <version>${project.version}</version>
       <exclusions>
diff --git a/container-core/src/main/java/com/yahoo/container/http/filter/FilterChainRepository.java b/container-core/src/main/java/com/yahoo/container/http/filter/FilterChainRepository.java
new file mode 100644
index 00000000000..31bceca9337
--- /dev/null
+++ b/container-core/src/main/java/com/yahoo/container/http/filter/FilterChainRepository.java
@@ -0,0 +1,201 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.container.http.filter;
+
+import com.yahoo.component.AbstractComponent;
+import com.yahoo.component.ComponentId;
+import com.yahoo.component.ComponentSpecification;
+import com.yahoo.component.chain.Chain;
+import com.yahoo.component.chain.ChainedComponent;
+import com.yahoo.component.chain.ChainsConfigurer;
+import com.yahoo.component.chain.model.ChainsModel;
+import com.yahoo.component.chain.model.ChainsModelBuilder;
+import com.yahoo.component.provider.ComponentRegistry;
+import com.yahoo.container.core.ChainsConfig;
+import com.yahoo.jdisc.http.filter.RequestFilter;
+import com.yahoo.jdisc.http.filter.ResponseFilter;
+import com.yahoo.jdisc.http.filter.SecurityRequestFilter;
+import com.yahoo.jdisc.http.filter.SecurityRequestFilterChain;
+import com.yahoo.jdisc.http.filter.SecurityResponseFilter;
+import com.yahoo.jdisc.http.filter.SecurityResponseFilterChain;
+import com.yahoo.jdisc.http.filter.chain.RequestFilterChain;
+import com.yahoo.jdisc.http.filter.chain.ResponseFilterChain;
+import com.yahoo.processing.execution.chain.ChainRegistry;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.logging.Logger;
+
+import static java.util.Collections.emptyList;
+import static java.util.stream.Collectors.toList;
+import static java.util.stream.Collectors.toSet;
+
+/**
+ * Creates JDisc request/response filter chains.
+ *
+ * @author Tony Vaagenes
+ * @author bjorncs
+ */
+public class FilterChainRepository extends AbstractComponent {
+    private static final Logger log = Logger.getLogger(FilterChainRepository.class.getName());
+
+    private final ComponentRegistry<Object> filterAndChains;
+
+    public FilterChainRepository(ChainsConfig chainsConfig,
+                                 ComponentRegistry<RequestFilter> requestFilters,
+                                 ComponentRegistry<ResponseFilter> responseFilters,
+                                 ComponentRegistry<SecurityRequestFilter> securityRequestFilters,
+                                 ComponentRegistry<SecurityResponseFilter> securityResponseFilters) {
+        ComponentRegistry<Object> filterAndChains = new ComponentRegistry<>();
+        addAllFilters(filterAndChains, requestFilters, responseFilters, securityRequestFilters, securityResponseFilters);
+        addAllChains(filterAndChains, chainsConfig, requestFilters, responseFilters, securityRequestFilters, securityResponseFilters);
+        filterAndChains.freeze();
+        this.filterAndChains = filterAndChains;
+    }
+
+    public Object getFilter(ComponentSpecification componentSpecification) {
+        return filterAndChains.getComponent(componentSpecification);
+    }
+
+    private static void addAllFilters(ComponentRegistry<Object> destination,
+                                      ComponentRegistry<?>... registries) {
+        for (ComponentRegistry<?> registry : registries) {
+            registry.allComponentsById()
+                    .forEach((id, filter) -> destination.register(id, wrapIfSecurityFilter(filter)));
+        }
+    }
+
+    private static void addAllChains(ComponentRegistry<Object> destination,
+                                     ChainsConfig chainsConfig,
+                                     ComponentRegistry<?>... filters) {
+        ChainRegistry<FilterWrapper> chainRegistry = buildChainRegistry(chainsConfig, filters);
+        chainRegistry.allComponents()
+                .forEach(chain -> destination.register(chain.getId(), toJDiscChain(chain)));
+    }
+
+    private static ChainRegistry<FilterWrapper> buildChainRegistry(ChainsConfig chainsConfig,
+                                                                   ComponentRegistry<?>... filters) {
+        ChainRegistry<FilterWrapper> chainRegistry = new ChainRegistry<>();
+        ChainsModel chainsModel = ChainsModelBuilder.buildFromConfig(chainsConfig);
+        ChainsConfigurer.prepareChainRegistry(chainRegistry, chainsModel, allFiltersWrapped(filters));
+        removeEmptyChains(chainRegistry);
+        chainRegistry.freeze();
+        return chainRegistry;
+    }
+
+    private static void removeEmptyChains(ChainRegistry<FilterWrapper> chainRegistry) {
+        chainRegistry.allComponents().stream()
+                .filter(chain -> chain.components().isEmpty())
+                .map(Chain::getId)
+                .peek(id -> log.warning("Removing empty filter chain: " + id))
+                .forEach(chainRegistry::unregister);
+    }
+
+    @SuppressWarnings("unchecked")
+    private static Object toJDiscChain(Chain<FilterWrapper> chain) {
+        if (chain.components().isEmpty())
+            throw new IllegalArgumentException("Empty filter chain: " + chain.getId());
+        checkFilterTypesCompatible(chain);
+        List<?> jdiscFilters = chain.components().stream()
+                        .map(filterWrapper -> filterWrapper.filter)
+                        .collect(toList());
+        List<?> wrappedFilters = wrapSecurityFilters(jdiscFilters);
+        Object head = wrappedFilters.get(0);
+        if (wrappedFilters.size() == 1) return head;
+        else if (head instanceof RequestFilter)
+            return RequestFilterChain.newInstance((List<RequestFilter>) wrappedFilters);
+        else if (head instanceof ResponseFilter)
+            return ResponseFilterChain.newInstance((List<ResponseFilter>) wrappedFilters);
+        throw new IllegalStateException();
+    }
+
+    private static List<?> wrapSecurityFilters(List<?> filters) {
+        List<Object> aggregatedSecurityFilters = new ArrayList<>();
+        List<Object> wrappedFilters = new ArrayList<>();
+        for (Object filter : filters) {
+            if (isSecurityFilter(filter)) {
+                aggregatedSecurityFilters.add(filter);
+            } else {
+                if (!aggregatedSecurityFilters.isEmpty()) {
+                    wrappedFilters.add(createSecurityChain(aggregatedSecurityFilters));
+                    aggregatedSecurityFilters.clear();
+                }
+                wrappedFilters.add(filter);
+            }
+        }
+        if (!aggregatedSecurityFilters.isEmpty()) {
+            wrappedFilters.add(createSecurityChain(aggregatedSecurityFilters));
+        }
+        return wrappedFilters;
+    }
+
+    private static void checkFilterTypesCompatible(Chain<FilterWrapper> chain) {
+        Set<ComponentId> requestFilters = chain.components().stream()
+                .filter(filter -> filter instanceof RequestFilter || filter instanceof SecurityRequestFilter)
+                .map(FilterWrapper::getId)
+                .collect(toSet());
+        Set<ComponentId> responseFilters = chain.components().stream()
+                .filter(filter -> filter instanceof ResponseFilter || filter instanceof SecurityResponseFilter)
+                .map(FilterWrapper::getId)
+                .collect(toSet());
+        if (!requestFilters.isEmpty() && !responseFilters.isEmpty()) {
+            throw new IllegalArgumentException(
+                    String.format(
+                            "Can't mix request and response filters in chain %s: request filters: %s, response filters: %s.",
+                            chain.getId(), requestFilters, responseFilters));
+        }
+    }
+
+    private static ComponentRegistry<FilterWrapper> allFiltersWrapped(ComponentRegistry<?>... registries) {
+        ComponentRegistry<FilterWrapper> wrappedFilters = new ComponentRegistry<>();
+        for (ComponentRegistry<?> registry : registries) {
+            registry.allComponentsById()
+                    .forEach((id, filter) -> wrappedFilters.register(id, new FilterWrapper(id, filter)));
+        }
+        wrappedFilters.freeze();
+        return wrappedFilters;
+    }
+
+    private static Object wrapIfSecurityFilter(Object filter) {
+        if (isSecurityFilter(filter)) return createSecurityChain(Collections.singletonList(filter));
+        return filter;
+    }
+
+    @SuppressWarnings("unchecked")
+    private static Object createSecurityChain(List<?> filters) {
+        Object head = filters.get(0);
+        if (head instanceof SecurityRequestFilter)
+            return SecurityRequestFilterChain.newInstance((List<SecurityRequestFilter>) filters);
+        else if (head instanceof SecurityResponseFilter)
+            return SecurityResponseFilterChain.newInstance((List<SecurityResponseFilter>) filters);
+        throw new IllegalArgumentException("Unexpected class " + head.getClass());
+    }
+
+    private static boolean isSecurityFilter(Object filter) {
+        return filter instanceof SecurityRequestFilter || filter instanceof SecurityResponseFilter;
+    }
+
+    private static class FilterWrapper extends ChainedComponent {
+        public final Object filter;
+        public final Class<?> filterType;
+
+        public FilterWrapper(ComponentId id, Object filter) {
+            super(id);
+            this.filter = filter;
+            this.filterType = getFilterType(filter);
+        }
+
+        private static Class<?> getFilterType(Object filter) {
+            if (filter instanceof RequestFilter)
+                return RequestFilter.class;
+            else if (filter instanceof ResponseFilter)
+                return ResponseFilter.class;
+            else if (filter instanceof SecurityRequestFilter)
+                return SecurityRequestFilter.class;
+            else if (filter instanceof SecurityResponseFilter)
+                return SecurityResponseFilter.class;
+            throw new IllegalArgumentException("Unsupported filter type: " + filter.getClass().getName());
+        }
+    }
+}