Remote Code Compiler is an online code compiler designed to support 11 programming languages, making it ideal for competitive programming and coding interviews. It utilizes Docker containers to execute code remotely, ensuring environment separation.
- Supports: Java, Kotlin, C, C++, C#, Golang, Python, Scala, Ruby, Rust, and Haskell.
- Integration with REST Calls (Long Polling and Push Notification), Apache Kafka, and Rabbit MQ Messages, as well as gRPC.
When a request arrives, the compiler gets to work by creating a special container just for compiling the code you sent. This container works closely with the main application, sharing its storage space for easy access to files. Once the code is compiled successfully, the compiler sets up separate containers for running each test. These containers work independently, each having its own space to run the code without being affected by others.
In the execution step, each container is assigned a set number of CPUs (consistent across all containers, with a recommended value of 0.1 CPUs per execution), as well as limits on memory and execution time. When the container hits either the memory threshold or the maximum time allowed, it is automatically terminated, and a user-facing error message is generated to explain the termination cause.
The compiler ensures the security of user code execution by sandboxing the execution environment and applying strict resource limits. Additionally, input sanitization and validation are performed to prevent code injection attacks.
The Remote Code Compiler employs sandboxing techniques to isolate user code executions from the underlying system. Each code execution occurs within a dedicated Docker container, providing a secure and contained environment. This isolation prevents unauthorized access to system resources and protects against potential security vulnerabilities.
Furthermore, all capabilities within a container are dropped to reduce the set of permissions available to processes inside the container. Within the container, the networking stack is completely disabled, only the loopback device is created. This effectively isolates the container from any network, including the host and the internet. Additionally, the container's filesystem is read-only, further enhancing security by preventing any modifications or tampering with the filesystem contents.
Strict resource limits are enforced to prevent resource exhaustion attacks and ensure fair resource allocation. The compiler sets limits on CPU usage, memory consumption, and execution time for each code execution. These limits mitigate the risk of denial-of-service (DoS) attacks and ensure the stability and reliability of the compiler platform.
Input sanitization measures are implemented to validate and sanitize user inputs before execution. This helps prevent code injection attacks and ensures that only safe and trusted inputs are processed by the compiler. By sanitizing inputs, the compiler reduces the risk of executing malicious code and maintains the integrity of the execution environment.
The compiler can scale horizontally to handle increased load by deploying multiple instances behind a load balancer. Each instance is stateless and can independently process incoming requests, ensuring high availability and performance.
Example of an input
{
"testCases": {
"test1": {
"input": "<YOUR_INPUT>",
"expectedOutput": "<YOUR_EXPECTED_OUTPUT>"
},
"test2": {
"input": "<YOUR_INPUT>",
"expectedOutput": "<YOUR_EXPECTED_OUTPUT>"
},
...
},
"sourceCode": "<YOUR_SOURCE_CODE>",
"language": "JAVA",
"timeLimit": 15,
"memoryLimit": 500
}NOTE: The memoryLimit is in MB and the timeLimit is in seconds.
Example of an ouput
The compiler cleans up your output, which means having extra spaces or line breaks does not affect the status of the response.
{
"verdict": "Accepted",
"statusCode": 100,
"error": "",
"testCasesResult": {
"test1": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "0 1 2 3 4 5 6 7 8 9",
"error": "",
"expectedOutput": "0 1 2 3 4 5 6 7 8 9",
"executionDuration": 175
},
"test2": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "9 8 7 1",
"error": "" ,
"expectedOutput": "9 8 7 1",
"executionDuration": 273
},
...
},
"compilationDuration": 328,
"averageExecutionDuration": 183,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "JAVA",
"dateTime": "2022-01-28T23:32:02.843465"
}NOTE: In the response the memoryLimit is in MB and the timeLimit is in milliseconde.
To run this project you need a docker engine running on your machine.
1- Build a docker image:
docker image build . -t compiler2- Create a volume:
docker volume create compiler3- build the necessary docker images used by the compiler
./environment/build.sh4- Run the container:
docker container run -p 8080:8082 -v /var/run/docker.sock:/var/run/docker.sock -v compiler:/compiler -e DELETE_DOCKER_IMAGE=true -e EXECUTION_MEMORY_MAX=10000 -e EXECUTION_MEMORY_MIN=0 -e EXECUTION_TIME_MAX=15 -e EXECUTION_TIME_MIN=0 -e MAX_REQUESTS=1000 -e MAX_EXECUTION_CPUS=0.2 -e COMPILATION_CONTAINER_VOLUME=compiler -t compiler- The value of the env variable DELETE_DOCKER_IMAGE is by default set to true, and that means that each docker image is deleted after the execution of the container.
- The value of the env variable EXECUTION_MEMORY_MAX is by default set to 10 000 MB, and represents the maximum value of memory limit that we can pass in the request. EXECUTION_MEMORY_MIN is by default set to 0.
- The value of the env variable EXECUTION_TIME_MAX is by default set to 15 sec, and represents the maximum value of time limit that we can pass in the request. EXECUTION_TIME_MIN is by default set to 0.
- MAX_REQUESTS represents the number of requests that can be executed in parallel. When this value is reached all incoming requests will be throttled, and the user will get 429 HTTP status code (there will be a retry in queue mode).
- MAX_EXECUTION_CPUS represents the maximum number of cpus to use for each execution (by default the maximum available cpus). If this value is set, then all requests will be throttled when the service reaches the maximum.
- COMPILATION_CONTAINER_VOLUME It should be the same as the volume created in step 2.
- MAX_TEST_CASES Maximum number of test cases a request should handle (by default it's set to 20)
For the documentation visit the swagger page at the following url : http://IP:PORT/swagger-ui.html
curl 'http://localhost:8080/api/compile/json' -X POST -H 'Content-Type: application/json; charset=UTF-8' --data-raw '{"sourcecode":"// Java code here\npublic class main {\n public static void main(String[] args) {\n System.out.println(\"NO\");\n }\n}", "language":"JAVA", "testCases": {"test1" : {"input" : "Test", "expectedOutput" : "NO"}}, "memoryLimit" : 500, "timeLimit": 15 }'NOTE: The memoryLimit is in MB and the timeLimit is in seconds.
Here is a list of Verdicts that can be returned by the compiler:
🎉 Accepted
{
"verdict": "Accepted",
"statusCode": 100,
"error": "",
"testCasesResult": {
"test1": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "0 1 2 3 4 5 6 7 8 9",
"error": "",
"expectedOutput": "0 1 2 3 4 5 6 7 8 9",
"executionDuration": 175
},
"test2": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "9 8 7 1",
"error": "" ,
"expectedOutput": "9 8 7 1",
"executionDuration": 273
},
...
},
"compilationDuration": 328,
"averageExecutionDuration": 183,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "JAVA",
"dateTime": "2022-01-28T23:32:02.843465"
}❌ Wrong Answer
{
"verdict": "Wrong Answer",
"statusCode": 200,
"error": "",
"testCasesResult": {
"test1": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "0 1 2 3 4 5 6 7 8 9",
"error": "",
"expectedOutput": "0 1 2 3 4 5 6 7 8 9",
"executionDuration": 175
},
"test2": {
"verdict": "Wrong Answer",
"verdictStatusCode": 200,
"output": "9 8 7 1",
"error": "" ,
"expectedOutput": "9 8 6 1",
"executionDuration": 273
}
},
"compilationDuration": 328,
"averageExecutionDuration": 183,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "JAVA",
"dateTime": "2022-01-28T23:32:02.843465"
}💩 Compilation Error
{
"verdict": "Compilation Error",
"statusCode": 300,
"error": "# command-line-arguments\n./main.go:5:10: undefined: i\n./main.go:6:21: undefined: i\n./main.go:7:9: undefined: i\n",
"testCasesResult": {},
"compilationDuration": 118,
"averageExecutionDuration": 0,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "GO",
"dateTime": "2022-01-28T23:32:02.843465"
}🕜 Time Limit Exceeded
{
"verdict": "Time Limit Exceeded",
"statusCode": 500,
"error": "Execution exceeded 15sec",
"testCasesResult": {
"test1": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "0 1 2 3 4 5 6 7 8 9",
"error": "",
"expectedOutput": "0 1 2 3 4 5 6 7 8 9",
"executionDuration": 175
},
"test2": {
"verdict": "Time Limit Exceeded",
"verdictStatusCode": 500,
"output": "",
"error": "Execution exceeded 15sec" ,
"expectedOutput": "9 8 7 1",
"executionDuration": 1501
}
},
"compilationDuration": 328,
"averageExecutionDuration": 838,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "JAVA",
"dateTime": "2022-01-28T23:32:02.843465"
}💥 Runtime Error
{
"verdict": "Runtime Error",
"statusCode": 600,
"error": "panic: runtime error: integer divide by zero\n\ngoroutine 1 [running]:\nmain.main()\n\t/app/main.go:11 +0x9b\n",
"testCasesResult": {
"test1": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "0 1 2 3 4 5 6 7 8 9",
"error": "",
"expectedOutput": "0 1 2 3 4 5 6 7 8 9",
"executionDuration": 175
},
"test2": {
"verdict": "Runtime Error",
"verdictStatusCode": 600,
"output": "",
"error": "panic: runtime error: integer divide by zero\n\ngoroutine 1 [running]:\nmain.main()\n\t/app/main.go:11 +0x9b\n" ,
"expectedOutput": "9 8 7 1",
"executionDuration": 0
}
},
"compilationDuration": 328,
"averageExecutionDuration": 175,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "GO",
"dateTime": "2022-01-28T23:32:02.843465"
}💽 Out Of Memory
{
"verdict": "Out Of Memory",
"statusCode": 400,
"error": "fatal error: runtime: out of memory\n\nruntime stack:\nruntime.throw({0x497d72?, 0x17487800000?})\n\t/usr/local/go/src/runtime/panic.go:992 +0x71\nruntime.sysMap(0xc000400000, 0x7ffccb36b0d0?, 0x7ffccb36b13...",
"testCasesResult": {
"test1": {
"verdict": "Accepted",
"verdictStatusCode": 100,
"output": "0 1 2 3 4 5 6 7 8 9",
"error": "",
"expectedOutput": "0 1 2 3 4 5 6 7 8 9",
"executionDuration": 175
},
"test2": {
"verdict": "Out Of Memory",
"verdictStatusCode": 400,
"output": "",
"error": "fatal error: runtime: out of memory\n\nruntime stack:\nruntime.throw({0x497d72?, 0x17487800000?})\n\t/usr/local/go/src/runtime/panic.go:992 +0x71\nruntime.sysMap(0xc000400000, 0x7ffccb36b0d0?, 0x7ffccb36b13..." ,
"expectedOutput": "9 8 7 1",
"executionDuration": 0
}
},
"compilationDuration": 328,
"averageExecutionDuration": 175,
"timeLimit": 1500,
"memoryLimit": 500,
"language": "GO",
"dateTime": "2022-01-28T23:32:02.843465"
}The compiler is equipped with some problems specified in the problems.json file located in the resource folder. These problem sets are automatically loaded upon project startup, granting you the opportunity to explore and test them through the /problems endpoint.
You may want to get the response later and to avoid http timeouts, you can use push notifications, to do so you should pass two header values (url where you want to get the response and set preferPush to prefer-push)
To enable push notifications you should set the environment variable ENABLE_PUSH_NOTIFICATION to true
You have also the possibility to use multipart requests, you typically can use these requests for file uploads and for transferring data of several types in a single request. The only limitation with that, is that you can specify only one test case.
See the documentation in the local folder, a docker-compose is provided.
docker-compose up --buildYou can use the provided helm chart to deploy the project on k8s, see the documentation in the k8s folder.
helm install compiler ./k8s/compilerWe provide you with a script to provision an AKS cluster to ease your deployment experience. See the documentation in the provisioning folder.
It is also possible to visualize information about the images and docker containers that are currently running using these endpoints
You can use the compiler with an event driven architecture. To enable kafka mode you should pass to the container the following env variables :
- ENABLE_KAFKA_MODE : True or False
- KAFKA_INPUT_TOPIC : Input topic, json request
- KAFKA_OUTPUT_TOPIC : Output topic, json response
- KAFKA_CONSUMER_GROUP_ID : Consumer group
- KAFKA_HOSTS : List of brokers
- CLUSTER_API_KEY : API key
- CLUSTER_API_SECRET : API Secret
- KAFKA_THROTTLING_DURATION : Throttling duration, by default set to 10000ms (when number of docker containers running reach MAX_REQUESTS, this value is used to do not lose the request and retry after this duration)
Note:
Having More partitions => More Parallelism => Better performance
docker container run -p 8080:8082 -v /var/run/docker.sock:/var/run/docker.sock -e DELETE_DOCKER_IMAGE=true -e EXECUTION_MEMORY_MAX=10000 -e EXECUTION_MEMORY_MIN=0 -e EXECUTION_TIME_MAX=15 -e EXECUTION_TIME_MIN=0 -e ENABLE_KAFKA_MODE=true -e KAFKA_INPUT_TOPIC=topic.input -e KAFKA_OUTPUT_TOPIC=topic.output -e KAFKA_CONSUMER_GROUP_ID=compilerId -e KAFKA_HOSTS=ip_broker1,ip_broker2,ip_broker3 -e API_KEY=YOUR_API_KEY -e API_SECRET=YOUR_API_SECRET -t compilerTo enable Rabbit MQ mode you should pass to the container the following env variables :
- ENABLE_RABBITMQ_MODE : True or False
- RABBIT_QUEUE_INPUT : Input queue, json request
- RABBIT_QUEUE_OUTPUT : Output queue, json response
- RABBIT_USERNAME : Rabbit MQ username
- RABBIT_PASSWORD : Rabbit MQ password
- RABBIT_HOSTS : List of brokers
- RABBIT_THROTTLING_DURATION : Throttling duration, by default set to 10000ms (when number of docker containers running reach MAX_REQUESTS, this value is used to do not lose the request and retry after this duration)
docker container run -p 8080:8082 -v /var/run/docker.sock:/var/run/docker.sock -e DELETE_DOCKER_IMAGE=true -e EXECUTION_MEMORY_MAX=10000 -e EXECUTION_MEMORY_MIN=0 -e EXECUTION_TIME_MAX=15 -e EXECUTION_TIME_MIN=0 -e ENABLE_RABBITMQ_MODE=true -e RABBIT_QUEUE_INPUT=queue.input -e RABBIT_QUEUE_OUTPUT=queue.output -e RABBIT_USERNAME=username -e RABBIT_PASSWORD=password -e RABBIT_HOSTS=ip_broker1,ip_broker2,ip_broker3 -t compilerCheck out exposed prometheus metrics using the following url : http://IP:PORT/prometheus
By default, only console logging is enabled.
You can store logs in a file and access to it using /logfile endpoint by setting the environment variable ROLLING_FILE_LOGGING to true. All logs will be kept for 7 days with a maximum size of 1 GB.
You can also send logs to logstash pipeline by setting these environment variables LOGSTASH_LOGGING to true and LOGSTASH_SERVER_HOST, LOGSTASH_SERVER_PORT to logstash and port values respectively.
If you encounter any issues or need assistance with the Remote Code Compiler, feel free to reach out for support. You can:
- Open an issue on GitHub: Issues
- Contact the project maintainers directly.
- Zakaria Maaraki - Initial work - zakariamaaraki









