Looking at a diff between 4.3.6 and 4.3.7, the only thing that seems relevant 
is this change, maybe the issue with multiple threads writing the config at the 
same time needs to be solved in a different way?

My guess is this fixed the race condition by making it atomic, but it doesn’t 
stop it from happening twice in quick succession.

commit 1221b0158d2494523cf94cc3f223bd552a2467c7
Author: Grzegorz Grzybek [email protected]<mailto:[email protected]>
Date:   Wed Feb 9 11:53:33 2022 +0100

    [KARAF-7389] Prevent two threads (feature installer, CM Event Dispatcher 
through fileinstall) writing the same config file

    (cherry picked from commit f3260d5ab641cdbf1bbd594875c07d974ed470a0)

diff --git 
a/features/core/src/main/java/org/apache/karaf/features/internal/service/FeatureConfigInstaller.java
 
b/features/core/src/main/java/org/apache/karaf/features/internal/service/FeatureConfigInstaller.java
index ba46eb3a2d..40bb666a34 100644
--- 
a/features/core/src/main/java/org/apache/karaf/features/internal/service/FeatureConfigInstaller.java
+++ 
b/features/core/src/main/java/org/apache/karaf/features/internal/service/FeatureConfigInstaller.java
@@ -139,2 +139,3 @@ public class FeatureConfigInstaller {
                     properties.put(CONFIG_KEY, cid.pid);
+                    cfg.update(cfgProps);
                     if (storage != null && configCfgStore) {
@@ -142,3 +143,2 @@ public class FeatureConfigInstaller {
                     }
-                    cfg.update(cfgProps);
                     try {
@@ -327,7 +327,9 @@ public class FeatureConfigInstaller {
             if (!cfgFile.exists()) {
+                File tmpCfgFile = File.createTempFile(cfgFile.getName(), 
".tmp", cfgFile.getParentFile());
                 if (jsonFormat) {
-                    Configurations.buildWriter().build(new 
FileWriter(cfgFile)).writeConfiguration(convertToDict(props));
+                    Configurations.buildWriter().build(new 
FileWriter(tmpCfgFile)).writeConfiguration(convertToDict(props));
                 } else {
-                    props.save(cfgFile);
+                    props.save(tmpCfgFile);
                 }
+                tmpCfgFile.renameTo(cfgFile);
             } else {

From: Jesse White <[email protected]>
Date: Tuesday, May 30, 2023 at 7:11 PM
To: [email protected] <[email protected]>
Subject: same configuration registered with multiple PIDs in 
ManagedServiceFactory
Hey folks,

I've encountered some odd behavior with Karaf 4.4.3, and I'd like to confirm if 
this is a bug or if there are some settings I can tune to alter the behavior.

Here's how to reproduce:

  *   Start Karaf 4.4.3 w/ JDK 11
  *   Install the managed factory example

     *   feature:repo-add 
mvn:org.apache.karaf.examples/karaf-config-example-features/4.4.3/xml

     *   feature:install karaf-config-example-managed-factory

  *   Copy the attached 'config.xml' file to the 'deploy/' directory
  *   Wait about 5 seconds, and notice the following output to the console
New configuration with pid 
org.apache.karaf.example.config.04388423-2d46-4308-8214-3dcd1e0b8fd0
key1 = value1
key2 = value2
org.apache.karaf.features.configKey = org.apache.karaf.example.config-abc
service.factoryPid = org.apache.karaf.example.config
service.pid = 
org.apache.karaf.example.config.04388423-2d46-4308-8214-3dcd1e0b8fd0
18:42:02.131 INFO [features-3-thread-1] Done.
18:42:10.999 INFO [fileinstall-/Users/jesse/labs/karaf/apache-karaf-4.4.3/etc] 
Creating configuration {org.apache.karaf.example.config~abc} from 
/Users/jesse/labs/karaf/apache-karaf-4.4.3/etc/org.apache.karaf.example.config-abc.cfg
New configuration with pid org.apache.karaf.example.config~abc
felix.fileinstall.filename = 
file:/Users/jesse/labs/karaf/apache-karaf-4.4.3/etc/org.apache.karaf.example.config-abc.cfg
key1 = value1
key2 = value2
org.apache.karaf.features.configKey = org.apache.karaf.example.config-abc
service.factoryPid = org.apache.karaf.example.config
service.pid = org.apache.karaf.example.config~abc


Note that the single config results in multiple callbacks under two separate 
pids. This seems isolated to cases where the deploy/ folder is used to write 
the config, and doesn't happen when the configuration is manually placed in 
etc/.

Following the same instructions with Karaf 4.3.6 has the expected behavior. 
Karaf 4.3.7 and later experience this issue though.

Any ideas?

Thanks,
Jesse



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