state lists feature (#17)

- adding additional `list` handling:
  - add items to list (first or last)
  - delete items from list (first, last, index, by property)
  - return selective entries from list
- adding request matchers `listSizeEqualTo`, `listSizeMoreThan`,
`listSizeLessThan`
  - adding explicit property `listSize` to use in response templates
- extended error reporting
- create common base for all tests
- extending documentation to cover new feature
- made sample test cases more "complete"

<!-- Please describe your pull request here. -->

## References

- #16 

<!-- References to relevant GitHub issues and pull requests, esp.
upstream and downstream changes -->

## Submitter checklist

- [x] The PR request is well described and justified, including the body
and the references
- [x] The PR title represents the desired changelog entry
- [x] The repository's code style is followed (see the contributing
guide)
- [x] Test coverage that demonstrates that the change works as expected
- [x] For new features, there's necessary documentation in this pull
request or in a subsequent PR to
[wiremock.org](https://github.com/wiremock/wiremock.org)

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Author: dirkbolte

README.md

@@ -15,6 +15,7 @@
  */
 package org.wiremock.extensions.state.extensions;
 
+import com.github.tomakehurst.wiremock.common.Json;
 import com.github.tomakehurst.wiremock.core.ConfigurationException;
 import com.github.tomakehurst.wiremock.extension.Parameters;
 import com.github.tomakehurst.wiremock.extension.ServeEventListener;
@@ -23,9 +24,13 @@
 import com.github.tomakehurst.wiremock.stubbing.ServeEvent;
 import org.apache.commons.lang3.StringUtils;
 import org.wiremock.extensions.state.internal.ContextManager;
+import org.wiremock.extensions.state.internal.DeleteStateParameters;
 import org.wiremock.extensions.state.internal.ResponseTemplateModel;
+import org.wiremock.extensions.state.internal.StateExtensionMixin;
 
+import java.util.LinkedList;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Optional;
 
 /**
@@ -35,7 +40,7 @@
  *
  * @see org.wiremock.extensions.state.StateExtension
  */
-public class DeleteStateEventListener implements ServeEventListener {
+public class DeleteStateEventListener implements ServeEventListener, StateExtensionMixin {
 
     private final TemplateEngine templateEngine;
     private final ContextManager contextManager;
@@ -46,15 +51,6 @@ public DeleteStateEventListener(ContextManager contextManager, TemplateEngine te
         this.templateEngine = templateEngine;
     }
 
-    public void afterComplete(ServeEvent serveEvent, Parameters parameters) {
-        var model = Map.of(
-            "request", RequestTemplateModel.from(serveEvent.getRequest()),
-            "response", ResponseTemplateModel.from(serveEvent.getResponse())
-        );
-        var contextName = createContextName(model, parameters);
-        contextManager.deleteContext(contextName);
-    }
-
     @Override
     public String getName() {
         return "deleteState";
@@ -65,11 +61,57 @@ public boolean applyGlobally() {
         return false;
     }
 
-    private String createContextName(Map<String, Object> model, Parameters parameters) {
-        var rawContext = Optional.ofNullable(parameters.getString("context")).filter(StringUtils::isNotBlank).orElseThrow(() -> new ConfigurationException("no context specified"));
+    public void afterComplete(ServeEvent serveEvent, Parameters parameters) {
+        var model = Map.of(
+            "request", RequestTemplateModel.from(serveEvent.getRequest()),
+            "response", ResponseTemplateModel.from(serveEvent.getResponse())
+        );
+        var configuration = Json.mapToObject(parameters, DeleteStateParameters.class);
+        var contextName = createContextName(model, configuration);
+        Optional.ofNullable(configuration.getList()).ifPresentOrElse(
+            listConfig -> handleListDeletion(listConfig, contextName, model),
+            () -> contextManager.deleteContext(contextName)
+        );
+    }
+
+    private void handleListDeletion(DeleteStateParameters.ListParameters listConfig, String contextName, Map<String, Object> model) {
+        if (Boolean.TRUE.equals(listConfig.getDeleteFirst())) {
+            contextManager.createOrUpdateContextList(contextName, LinkedList::removeFirst);
+        } else if (Boolean.TRUE.equals(listConfig.getDeleteLast())) {
+            contextManager.createOrUpdateContextList(contextName, LinkedList::removeLast);
+        } else if (StringUtils.isNotBlank(listConfig.getDeleteIndex())) {
+            try {
+                var index = Integer.parseInt(renderTemplate(model, listConfig.getDeleteIndex()));
+                contextManager.createOrUpdateContextList(contextName, list -> list.remove(index));
+            } catch (IndexOutOfBoundsException | NumberFormatException e) {
+                throw createConfigurationError("List index '%s' does not exist or cannot be parsed: %s", listConfig.getDeleteIndex(), e.getMessage());
+            }
+        } else if (listConfig.getDeleteWhere() != null &&
+            listConfig.getDeleteWhere().getProperty() != null &&
+            listConfig.getDeleteWhere().getValue() != null
+        ) {
+            var property = renderTemplate(model, listConfig.getDeleteWhere().getProperty());
+            var value = renderTemplate(model, listConfig.getDeleteWhere().getValue());
+            contextManager.createOrUpdateContextList(contextName, list -> {
+                var iterator = list.iterator();
+                while (iterator.hasNext()) {
+                    var element = iterator.next();
+                    if (Objects.equals(element.getOrDefault(property, null), value)) {
+                        iterator.remove();
+                        break;
+                    }
+                }
+            });
+        } else {
+            throw createConfigurationError("Missing/invalid configuration for list");
+        }
+    }
+
+    private String createContextName(Map<String, Object> model, DeleteStateParameters parameters) {
+        var rawContext = Optional.ofNullable(parameters.getContext()).filter(StringUtils::isNotBlank).orElseThrow(() -> new ConfigurationException("no context specified"));
         String context = renderTemplate(model, rawContext);
         if (StringUtils.isBlank(context)) {
-            throw new ConfigurationException("context is blank");
+            throw createConfigurationError("Context cannot be blank");
         }
         return context;
     }

src/main/java/org/wiremock/extensions/state/extensions/DeleteStateEventListener.java

@@ -15,6 +15,7 @@
  */
 package org.wiremock.extensions.state.extensions;
 
+import com.github.tomakehurst.wiremock.common.Json;
 import com.github.tomakehurst.wiremock.core.ConfigurationException;
 import com.github.tomakehurst.wiremock.extension.Parameters;
 import com.github.tomakehurst.wiremock.extension.ServeEventListener;
@@ -23,7 +24,9 @@
 import com.github.tomakehurst.wiremock.stubbing.ServeEvent;
 import org.apache.commons.lang3.StringUtils;
 import org.wiremock.extensions.state.internal.ContextManager;
+import org.wiremock.extensions.state.internal.RecordStateParameters;
 import org.wiremock.extensions.state.internal.ResponseTemplateModel;
+import org.wiremock.extensions.state.internal.StateExtensionMixin;
 
 import java.util.Map;
 import java.util.Optional;
@@ -36,7 +39,7 @@
  *
  * @see org.wiremock.extensions.state.StateExtension
  */
-public class RecordStateEventListener implements ServeEventListener {
+public class RecordStateEventListener implements ServeEventListener, StateExtensionMixin {
 
     private final TemplateEngine templateEngine;
     private final ContextManager contextManager;
@@ -51,8 +54,10 @@ public void afterComplete(ServeEvent serveEvent, Parameters parameters) {
             "request", RequestTemplateModel.from(serveEvent.getRequest()),
             "response", ResponseTemplateModel.from(serveEvent.getResponse())
         );
+        var configuration = Json.mapToObject(parameters, RecordStateParameters.class);
         var contextName = createContextName(model, parameters);
-        storeContextAndState(contextName, model, parameters);
+        handleState(contextName, model, configuration);
+        handleList(contextName, model, configuration);
     }
 
     @Override
@@ -65,29 +70,43 @@ public boolean applyGlobally() {
         return false;
     }
 
-    private void storeContextAndState(String context, Map<String, Object> model, Parameters parameters) {
-        @SuppressWarnings("unchecked") Map<String, Object> state = Optional.ofNullable(parameters.get("state"))
-            .filter(it -> it instanceof Map)
-            .map(Map.class::cast)
-            .orElseThrow(() -> new ConfigurationException("no state specified"));
-        var properties = state.entrySet()
+    private void handleState(String contextName, Map<String, Object> model, RecordStateParameters parameters) {
+        Optional.ofNullable(parameters.getState())
+            .ifPresent(configuration ->
+                contextManager.createOrUpdateContextState(contextName, getPropertiesFromConfiguration(model, configuration))
+            );
+    }
+
+    private Map<String, String> getPropertiesFromConfiguration(Map<String, Object> model, Map<String, String> configuration) {
+        return configuration.entrySet()
             .stream()
-            .map(entry -> Map.entry(entry.getKey(), renderTemplate(model, entry.getValue().toString())))
+            .map(entry -> Map.entry(entry.getKey(), renderTemplate(model, entry.getValue())))
             .collect(Collectors.toUnmodifiableMap(Map.Entry::getKey, Map.Entry::getValue));
+    }
 
-        contextManager.createOrUpdateContext(context, properties);
+    private void handleList(String contextName, Map<String, Object> model, RecordStateParameters parameters) {
+        Optional.ofNullable(parameters.getList())
+            .ifPresent(listConfiguration -> {
+                    Optional.ofNullable(listConfiguration.getAddFirst())
+                        .ifPresent(configuration ->
+                        contextManager.createOrUpdateContextList(contextName, list -> list.addFirst(getPropertiesFromConfiguration(model, configuration))));
+                    Optional.ofNullable(listConfiguration.getAddLast()).ifPresent(configuration ->
+                        contextManager.createOrUpdateContextList(contextName, list -> list.addLast(getPropertiesFromConfiguration(model, configuration))));
+                }
+            );
     }
 
     private String createContextName(Map<String, Object> model, Parameters parameters) {
         var rawContext = Optional.ofNullable(parameters.getString("context")).filter(StringUtils::isNotBlank).orElseThrow(() -> new ConfigurationException("no context specified"));
         String context = renderTemplate(model, rawContext);
         if (StringUtils.isBlank(context)) {
-            throw new ConfigurationException("context is blank");
+            throw createConfigurationError("context cannot be blank");
         }
         return context;
     }
 
     private String renderTemplate(Object context, String value) {
         return templateEngine.getUncachedTemplate(value).apply(context);
     }
+
 }

src/main/java/org/wiremock/extensions/state/extensions/RecordStateEventListener.java

@@ -15,8 +15,10 @@
  */
 package org.wiremock.extensions.state.extensions;
 
+import com.fasterxml.jackson.core.JsonParser;
 import com.github.jknack.handlebars.Options;
 import com.github.tomakehurst.wiremock.extension.responsetemplating.helpers.HandlebarsHelper;
+import com.jayway.jsonpath.JsonPath;
 import org.apache.commons.lang3.StringUtils;
 import org.wiremock.extensions.state.internal.ContextManager;
 
@@ -39,20 +41,39 @@ public StateHandlerbarHelper(ContextManager contextManager) {
     public Object apply(Object o, Options options) {
         String contextName = options.hash("context");
         String property = options.hash("property");
+        String list = options.hash("list");
         if (StringUtils.isEmpty(contextName)) {
             return handleError("'context' cannot be empty");
         }
-        if (StringUtils.isEmpty(property)) {
-            return handleError("'property' cannot be empty");
+        if (StringUtils.isBlank(property) && StringUtils.isBlank(list)) {
+            return handleError("Either 'property' or 'list' has to be set");
         }
+        if (StringUtils.isNotBlank(property) && StringUtils.isNotBlank(list)) {
+            return handleError("Either 'property' or 'list' has to be set");
+        }
+        if (StringUtils.isNotBlank(property)) {
+            return getProperty(contextName, property);
+        } else {
+            return getList(contextName, list);
+        }
+    }
+
+    private Object getProperty(String contextName, String property) {
         return contextManager.getContext(contextName)
             .map(context -> {
                     if ("updateCount".equals(property)) {
                         return context.getUpdateCount();
+                    } else if ("listSize".equals(property)) {
+                        return context.getList().size();
                     } else {
                         return context.getProperties().get(property);
                     }
                 }
             ).orElse(handleError(String.format("No state for context %s, property %s found", contextName, property)));
     }
+    private Object getList(String contextName, String list) {
+        return contextManager.getContext(contextName)
+            .map(context -> JsonPath.read(context.getList(), list))
+            .orElse(handleError(String.format("No state for context %s, list %s found", contextName, list)));
+    }
 }

src/main/java/org/wiremock/extensions/state/extensions/StateHandlerbarHelper.java

@@ -15,7 +15,6 @@
  */
 package org.wiremock.extensions.state.extensions;
 
-import com.github.tomakehurst.wiremock.core.ConfigurationException;
 import com.github.tomakehurst.wiremock.extension.Parameters;
 import com.github.tomakehurst.wiremock.extension.responsetemplating.RequestTemplateModel;
 import com.github.tomakehurst.wiremock.extension.responsetemplating.TemplateEngine;
@@ -25,6 +24,7 @@
 import org.wiremock.extensions.state.internal.Context;
 import org.wiremock.extensions.state.internal.ContextManager;
 import org.wiremock.extensions.state.internal.ContextTemplateModel;
+import org.wiremock.extensions.state.internal.StateExtensionMixin;
 
 import java.util.Arrays;
 import java.util.HashMap;
@@ -41,7 +41,7 @@
  *
  * @see org.wiremock.extensions.state.StateExtension
  */
-public class StateRequestMatcher extends RequestMatcherExtension {
+public class StateRequestMatcher extends RequestMatcherExtension implements StateExtensionMixin {
 
     private final TemplateEngine templateEngine;
     private final ContextManager contextManager;
@@ -72,7 +72,7 @@ public MatchResult match(Request request, Parameters parameters) {
             .ofNullable(parameters.getString("hasContext", null))
             .map(template -> hasContext(model, parameters, template))
             .or(() -> Optional.ofNullable(parameters.getString("hasNotContext", null)).map(template -> hasNotContext(model, template)))
-            .orElseThrow(() -> new ConfigurationException("Parameters should only contain 'hasContext' or 'hasNotContext'"));
+            .orElseThrow(() -> createConfigurationError("Parameters should only contain 'hasContext' or 'hasNotContext'"));
     }
 
     private MatchResult hasContext(Map<String, Object> model, Parameters parameters, String template) {
@@ -114,7 +114,10 @@ String renderTemplate(Object context, String value) {
     private enum CountMatcher {
         updateCountEqualTo((Context context, Long value) -> context.getUpdateCount().equals(value)),
         updateCountLessThan((Context context, Long value) -> context.getUpdateCount() < value),
-        updateCountMoreThan((Context context, Long value) -> context.getUpdateCount() > value);
+        updateCountMoreThan((Context context, Long value) -> context.getUpdateCount() > value),
+        listSizeEqualTo((Context context, Long value) -> context.getList().size() == value),
+        listSizeLessThan((Context context, Long value) -> context.getList().size() < value),
+        listSizeMoreThan((Context context, Long value) -> context.getList().size() > value);
 
         private final BiFunction<Context, Long, Boolean> evaluator;
 

src/main/java/org/wiremock/extensions/state/extensions/StateRequestMatcher.java

@@ -17,13 +17,15 @@
 
 import java.util.HashMap;
 import java.util.LinkedList;
+import java.util.List;
 import java.util.Map;
 
 public class Context {
 
     private static final int MAX_IDS = 10;
     private final String contextName;
     private final Map<String, String> properties = new HashMap<>();
+    private final LinkedList<Map<String, String>> list = new LinkedList<>();
     private final LinkedList<String> requests = new LinkedList<>();
     private Long updateCount = 1L;
     private Long matchCount = 0L;
@@ -66,12 +68,17 @@ public Map<String, String> getProperties() {
         return properties;
     }
 
+    public LinkedList<Map<String, String>> getList() {
+        return list;
+    }
+
     @Override
     public String toString() {
         return "Context{" +
             "contextName='" + contextName + '\'' +
-            ", updateCount=" + updateCount +
             ", properties=" + properties +
+            ", list=" + list +
+            ", updateCount=" + updateCount +
             '}';
     }
 }

src/main/java/org/wiremock/extensions/state/internal/Context.java

@@ -17,8 +17,10 @@
 
 import com.github.tomakehurst.wiremock.store.Store;
 
+import java.util.LinkedList;
 import java.util.Map;
 import java.util.Optional;
+import java.util.function.Consumer;
 
 public class ContextManager {
 
@@ -46,7 +48,7 @@ public void deleteContext(String contextName) {
         }
     }
 
-    public Long createOrUpdateContext(String contextName, Map<String, String> properties) {
+    public Long createOrUpdateContextState(String contextName, Map<String, String> properties) {
         synchronized (store) {
             var context = store.get(contextName)
                 .map(it -> (Context) it)
@@ -60,6 +62,20 @@ public Long createOrUpdateContext(String contextName, Map<String, String> proper
         }
     }
 
+    public Long createOrUpdateContextList(String contextName, Consumer<LinkedList<Map<String, String>>> consumer) {
+        synchronized (store) {
+            var context = store.get(contextName)
+                .map(it -> (Context) it)
+                .map(it -> {
+                    it.incUpdateCount();
+                    return it;
+                }).orElseGet(() -> new Context(contextName));
+            consumer.accept(context.getList());
+            store.put(contextName, context);
+            return context.getUpdateCount();
+        }
+    }
+
     public Long numUpdates(String contextName) {
         synchronized (store) {
             return store.get(contextName).map(it -> ((Context) it).getUpdateCount()).orElse(0L);