Guard null in GlobalVariableStore lock/unlock

[NicoPiel]

$gc()/$g() JS APIs call lock() on keys never registered via putSync(), causing NPE; throw IllegalArgumentException with clear message instead

[github-actions]

Test Results

  111 files  ±0    214 suites  ±0   6m 59s ⏱️ + 1m 9s
  654 tests ±0    654 ✅ ±0  0 💤 ±0  0 ❌ ±0 
1 308 runs  ±0  1 308 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit 2e0ff41. ± Comparison against base commit 5423492.

[mgaffigan]

How can this issue be reproduced?

[NicoPiel]

JavaScript transformer in any channel:

// Never called putSync("myKey", ...) first
globalMap.lock("myKey");   // → NPE

More realistic scenari: race condition or misconfigured channel:

// Channel A clears sync map or removes a key
globalMap.clearSync();  // or globalMap.removeSync("sharedKey")

// Channel B (running concurrently) tries to lock the now-missing key
globalMap.lock("sharedKey");  // → NPE

Will throw something like:

DETAILS:	Wrapped java.lang.NullPointerException: Cannot invoke "com.mirth.connect.server.util.SyncObject.getLock()" because the return value of "java.util.Map.get(Object)" is null
	at b3ce21c4-952b-47ff-88d6-8b5cdf19fcfe_JavaScript_Filter_Transformer_0:103 (doTransform)
	at b3ce21c4-952b-47ff-88d6-8b5cdf19fcfe_JavaScript_Filter_Transformer_0:125 (doScript)
	at b3ce21c4-952b-47ff-88d6-8b5cdf19fcfe_JavaScript_Filter_Transformer_0:127
	at com.mirth.connect.server.transformers.JavaScriptFilterTransformer$FilterTransformerTask.doCall(JavaScriptFilterTransformer.java:235)
	at com.mirth.connect.server.transformers.JavaScriptFilterTransformer$FilterTransformerTask.doCall(JavaScriptFilterTransformer.java:187)
	at com.mirth.connect.server.util.javascript.JavaScriptTask.call(JavaScriptTask.java:114)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:840)
Caused by: java.lang.NullPointerException: Cannot invoke "com.mirth.connect.server.util.SyncObject.getLock()" because the return value of "java.util.Map.get(Object)" is null
	at com.mirth.connect.server.util.GlobalVariableStore.lock(GlobalVariableStore.java:72)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:569)
	at org.mozilla.javascript.MemberBox.invoke(MemberBox.java:138)
	at org.mozilla.javascript.NativeJavaMethod.call(NativeJavaMethod.java:226)
	at org.mozilla.javascript.Interpreter.interpretLoop(Interpreter.java:1692)
	at org.mozilla.javascript.Interpreter.interpret(Interpreter.java:1013)
	at org.mozilla.javascript.InterpretedFunction.call(InterpretedFunction.java:109)
	at org.mozilla.javascript.ContextFactory.doTopCall(ContextFactory.java:412)
	at org.mozilla.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3578)
	at org.mozilla.javascript.InterpretedFunction.exec(InterpretedFunction.java:121)
	at com.mirth.connect.server.util.javascript.JavaScriptTask.executeScript(JavaScriptTask.java:151)
	at com.mirth.connect.server.transformers.JavaScriptFilterTransformer$FilterTransformerTask.doCall(JavaScriptFilterTransformer.java:224)
	... 6 more

[kryskool]

Works for me