Change getExposedPorts to return port w/ protocol (#349)

* Change getExposedPorts to return port w/ protocol

* member ordering

* Add comment to explain using the port prefix

commands/start-container.ts

@@ -29,7 +29,8 @@ export async function startContainer(context?: ImageNode, interactive?: boolean)
         docker.getExposedPorts(imageToStart.Id).then((ports: string[]) => {
             let options = `--rm ${interactive ? '-it' : '-d'}`;
             if (ports.length) {
-                const portMappings = ports.map((port) => `-p ${port}:${port}`);
+                const portMappings = ports.map((port) => `-p ${port.split("/")[0]}:${port}`); //'port' is of the form number/protocol, eg. 8080/udp.
+                // In the command, the host port has just the number (mentioned in the EXPOSE step), while the destination port can specify the protocol too
                 options += ` ${portMappings.join(' ')}`;
             }
 

commands/utils/docker-endpoint.ts

@@ -107,7 +107,7 @@ class DockerClient {
     public getExposedPorts(imageId: string): Thenable<string[]> {
         return new Promise((resolve, reject) => {
             this.getImage(imageId).inspect((error, { Config: { ExposedPorts = {} } }) => {
-                const ports = Object.keys(ExposedPorts).map((port) => port.split("/")[0]);
+                const ports = Object.keys(ExposedPorts);
                 resolve(ports);
             });
         });