Patch Integrator (PI)

The goal of this project is to integrate missed patches from base repository to a divergent variant fork. It extends the work done in RefactoringInMergeCommits project.

Project Context

LinkedIn is a clone-and-own variant of Apache Kafka that was created by copying and adapting the existing code of Apache Kafka that was forked on 2011-08-15T18:06:16Z. The two software systems kept on synchronizing their new updates until 2021-07-06T17:39:59Z. Since 2021-07-06T17:39:59Z (divergence date), the two projects do not share common commits yet actively evolve in parallel. Currently, ( as of 2022-10-01T15:01:39Z), LinkedIn has 367 individual commits, and Apache Kafka has 1,216 individual commits. Development becomes redundant with the continued divergence, and maintenance efforts rapidly grow. For example, if a bug is discovered in a shared file and fixed in one variant, it is not easy to tell if it has been fixed in the other variant.

System Requirements

• Linux or macOS
• git
• GitHub
• Java 11
• MySQL 5.7

Dependencies

Project dependencies are easily managed using gradle build tool.

dependencies {
    testCompile group: 'junit', name: 'junit', version: '4.12'
    testImplementation 'org.junit.jupiter:junit-jupiter-engine:5.9.2'
    implementation 'com.github.tsantalis:refactoring-miner:2.3.2'
    implementation 'org.kohsuke:github-api:1.135'
    implementation 'commons-cli:commons-cli:1.2'
    implementation 'org.eclipse.jgit:org.eclipse.jgit:6.4.0.202211300538-r'
    implementation 'org.apache.logging.log4j:log4j-api:2.20.0'
    implementation 'org.apache.logging.log4j:log4j-core:2.20.0'
    implementation 'org.javalite:activejdbc:2.2'
    implementation 'org.javalite:activejdbc-instrumentation:2.3'
    implementation 'mysql:mysql-connector-java:8.0.32'
}

Running Patch Integrator

1. Database Setting

PI runs on MySQL database engine. Modify the database.properties file and add your MySQL username and password:

development.driver=com.mysql.cj.jdbc.Driver
development.username=USERNAME
development.password=PASSWORD
development.url=jdbc:mysql://localhost/Patch_Integrator

You can choose a different database name. To do this, simply edit Patch_Integrator in the development.url property above. Please make sure that another database with the same name doesn't exist, since it'll most likely have a different schema and the program will run into problems.

2. Create Dataset

The program requires a text file consisting of the following: (i) GitHub repo of the mainline (SOURCE_REPO), (ii) GitHub repo of the divergent fork (DIVERGENT_REPO) and (iii) list of patches to be integrate from mainline to divergent fork. Each line in the text file should include the complete URL of repos in common separated format. We have included a sample of the reposList.txt file.

3. Build the Project

PI can be built using gradle build tool:

./gradlew build

Run the project using;

./gradlew run

Note that the results will be stored in MySQL database configured in step 1 above.

You can also run unit tests:

./gradlew test

To build a jar file run ./gradlew build, the jar file will be stored in build > libs directory with the file name: PatchIntegrator-1.0-SNAPSHOT.jar

4. Run the JAR

You can run the JAR file with the following command:

java -jar PatchIntegrator-1.0-SNAPSHOT.jar [OPTIONS]

Note that none of the options are required. Here is a list of available options:

-c,--clonepath <file>        directory to temporarily download repositories (default=projects)
-d,--dbproperties <file>     database properties file (default=database.properties)
-h,--help                    print this message
-p,--parallelism <threads>   number of threads for parallel computing (default=1)
-r,--reposfile <file>        list of repositories to be analyzed (default=reposList.txt)

Here is an example command with all the options:

 java -jar PatchIntegrator-1.0-SNAPSHOT.jar -r reposList.txt -c projects -d mydb.properties -p 8 

5. Analysis