From 0df139edb329efbb7dfad769ef500ea48f6818b7 Mon Sep 17 00:00:00 2001
From: Dirk Bolte <dirk.bolte@gmx.de>
Date: Fri, 1 Mar 2024 10:34:55 +0100
Subject: [PATCH] bug: prevent java.util.ConcurrentModificationException in
 Transaction (#120)

- copy context set to work on individual entity
- updated demo documentation

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## References

#119

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upstream and downstream changes -->

## Submitter checklist

- [x] Recommended: Join [WireMock Slack](https://slack.wiremock.org/) to
get any help in `#help-contributing` or a project-specific channel like
`#wiremock-java`
- [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
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---
 demo/README.md                                | 24 +++++++++++++++++--
 demo/docker_container_test.http               |  8 +++++++
 .../extensions/TransactionEventListener.java  |  1 -
 .../state/internal/TransactionManager.java    |  3 ++-
 4 files changed, 32 insertions(+), 4 deletions(-)
 create mode 100644 demo/docker_container_test.http

diff --git a/demo/README.md b/demo/README.md
index e2bcf94..dda7683 100644
--- a/demo/README.md
+++ b/demo/README.md
@@ -89,11 +89,31 @@ cd wiremock-state-extension
 
 ### Step 2: Build the Project
 
+From directory of this README:
+
+```shell
+cd ..
 ./gradlew build
+```
+
+### Step 3: download wiremock standalone
+
+From directory of this README:
+
+```shell
+cd ..
+curl -o build/libs/wiremock-standalone-3.4.1.jar https://repo1.maven.org/maven2/org/wiremock/wiremock-standalone/3.4.1/wiremock-standalone-3.4.1.jar
+```
+
+### Step 4: Start WireMock with the State Extension
 
-### Start WireMock with the State Extension
+From directory of this README:
+
+```shell
+cd ..
+java -cp build/libs/wiremock-state-extension-standalone-0.6.0-SNAPSHOT.jar:build/libs/wiremock-standalone-3.4.1.jar wiremock.Run --verbose --global-response-templating --root-dir demo/stubs
+```
 
-java -jar build/libs/wiremock-standalone-*.jar --extensions="com.github.tomakehurst.wiremock.extension.StateExtension"
 This command starts WireMock with the State Extension enabled.
 
 ### Access the Demo
diff --git a/demo/docker_container_test.http b/demo/docker_container_test.http
new file mode 100644
index 0000000..842cf50
--- /dev/null
+++ b/demo/docker_container_test.http
@@ -0,0 +1,8 @@
+### empty get
+
+POST http://localhost:8080//api/v1/todolist
+
+{
+  "title": "a",
+  "description": "as"
+}
diff --git a/src/main/java/org/wiremock/extensions/state/extensions/TransactionEventListener.java b/src/main/java/org/wiremock/extensions/state/extensions/TransactionEventListener.java
index 6019ab1..c703af9 100644
--- a/src/main/java/org/wiremock/extensions/state/extensions/TransactionEventListener.java
+++ b/src/main/java/org/wiremock/extensions/state/extensions/TransactionEventListener.java
@@ -54,6 +54,5 @@ public void afterComplete(ServeEvent serveEvent, Parameters parameters) {
         String requestId = serveEvent.getId().toString();
         var contextNames = transactionManager.getContextNamesByRequestId(requestId);
         contextNames.forEach((contextName) -> transactionManager.deleteTransaction(requestId, contextName));
-
     }
 }
diff --git a/src/main/java/org/wiremock/extensions/state/internal/TransactionManager.java b/src/main/java/org/wiremock/extensions/state/internal/TransactionManager.java
index 662aaf6..23cac73 100644
--- a/src/main/java/org/wiremock/extensions/state/internal/TransactionManager.java
+++ b/src/main/java/org/wiremock/extensions/state/internal/TransactionManager.java
@@ -19,6 +19,7 @@
 import org.wiremock.extensions.state.internal.model.Transaction;
 
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import java.util.function.Consumer;
@@ -59,7 +60,7 @@ public Set<String> getContextNamesByRequestId(String requestId) {
         var transactionKey = createTransactionKey(requestId);
         synchronized (store) {
             @SuppressWarnings("unchecked") var requestTransactions = store.get(transactionKey).map(it -> (Map<String, Transaction>) it).orElse(new HashMap<>());
-            return requestTransactions.keySet();
+            return new HashSet<>(requestTransactions.keySet());
         }
     }