updated readme

README.md

@@ -48,7 +48,7 @@ To be configured on the repository settings.
 Clone the repository with the following command:
 
 ```bash
-git clone https://github.com/intertwin-eu/interlink-docker-plugin-docker-plugin.git && cd interlink-docker-plugin
+git clone https://github.com/interTwin-eu/interlink-docker-plugin.git && cd interlink-docker-plugin
 ```
 
 and run the following command to build the docker image:
@@ -63,5 +63,64 @@ docker build . -t  <image_name>:<tag> -f docker/Dockerfile.sidecar-docker
 To build the plugin executable, clone the repository and run the makefile:
 
 ```bash
-git clone https://github.com/intertwin-eu/interlink-docker-plugin-docker-plugin.git && cd interlink-docker-plugin && make 
+git clone https://github.com/interTwin-eu/interlink-docker-plugin.git && cd interlink-docker-plugin && make 
+```
+
+## Docker plugin logic and configuration
+
+An Interlink plugin is the last component of the InterLink chain (check here the InterLink flow ...). 
+In particular, the docker plugin is responsible for executing the requests coming from the InterLink server, i.e. the requests to create, delete, logs and status of a POD, as docker containers.
+There are two main versions of the plugin that correspond with two different branches of the repository: the main and the 2-light-version-no-gpu.
+The main version of the plugin supports the creation of docker containers with GPU support, while the 2-light-version-no-gpu does not support GPU. In the first case, to build the binary executable, the following command should be used:
+
+```bash
+CGO_ENABLED=1 GOOS=linux go build -o bin/docker-sd cmd/main.go
+```
+As you can see, the CGO_ENABLED flag is set to 1, which means that the plugin will be built to allow the GO program to use C code. This is necessary to use the Nvidia GPU libraries.
+In the second case, the command is the following:
+
+```bash
+CGO_ENABLED=0 GOOS=linux go build -o bin/docker-sd cmd/main.go
+```
+In this case, the CGO_ENABLED flag is set to 0, which means that the plugin will be built without the support of C code, and therefore without the support of Nvidia GPU libraries but with the advantage of a lighter version of the plugin.
+
+When the docker plugin receives a create request from the InterLink server, it will first prepare and create all the necessary files to run the docker containers associated with the request. Then, it will use the docker API to create a DIND container (Docker in Docker) in which all the POD's containers will be executed.
+Therefore, a POD request coming from the InterLink server will be translated into a DIND container. 
+The reason for this choice is that the DIND container allows the plugin to execute the docker containers associated with the POD request in a controlled environment, without interfering with the host machine's docker containers. Moreover, to a DIND container a docker network is attached, which allows the containers to communicate with each other in a secure way, without exposing the ports to the host machine.
+The docker images of the docker host are shared with the DIND container, so that the containers can be executed in the DIND container without the need to download them again.
+Overall, even if the DIND container is a heavier solution that introduces an overhead in the execution of the containers, this choice is cleaner than running the containers directly on the host machine, as it allows the plugin to manage the containers in a more controlled way.
+The following figure shows the architecture of the plugin:
+
+<img src="img/dockerplugin.png" width="300">
+
+When a delete request is received, the plugin will force the stop of the DIND container and remove it. The plugin will also remove all the files created for the POD request.
+When a logs request is received, the plugin will return the logs of the specified container running in the DIND container.
+When a status request is received, the plugin will return the status of the specified container running in the DIND container.
+If you want to run the plugin as a binary executable, you first have to export the configuration file as an environment variable:
+
+```bash
+export INTERLINKCONFIGPATH=<path_to_config_file>
+```
+An example of configuration file can be the following:
+```yaml
+InterlinkURL: "http://127.0.0.1"
+SidecarURL: "http://127.0.0.1"
+InterlinkPort: "3000"
+SidecarPort: "4000"
+CommandPrefix: ""
+ExportPodData: true
+DataRootFolder: ".local/interlink/jobs/"
+ServiceAccount: "interlink"
+Namespace: "vk"
+Tsocks: false
+TsocksPath: "$WORK/tsocks-1.8beta5+ds1/libtsocks.so"
+TsocksLoginNode: "login01"
+BashPath: /bin/bash
+VerboseLogging: true
+ErrorsOnlyLogging: false
+```
+and then run the plugin with the following command:
+
+```bash
+./bin/docker-sd
 ```