Revised README, also add EOL at end of file

Attempt to fix trailing white space

Checked for typos

Fix minor formatting error, test Git still works

WIP: update top-level README

Author: Jiaxin Fan

README.md

@@ -114,3 +114,4 @@ This will return the following runtime images with the following names: `action-
 ```
 ./gradlew :tests:test
 ```
+An update about the details of verifying a standalone container can be found [here](https://github.com/apache/openwhisk-runtime-nodejs/pull/227/files#diff-c115bfeccd5f4a2e984d66e08ad3b677350baecacc248bc20d7585c2b6fe11e8)

tests/src/test/standalone/README.md

@@ -26,32 +26,64 @@ The following example shows how to generate a Docker image for the Node.js 18 ru
 ```
 ./gradlew core:nodejs18Action:distDocker
 ```
-This will return the following runtime image with the name `action-nodejs-v18`
+This will return the following runtime image with the name `action-nodejs-v18`, which should be listed after using the `docker images`
 
 ## Running the Container
-For the purpose of the test. We are going to access the the runner container via `localhost`.
-The `Action` container exposes `port 8080` (see the Dockerfile for the associated Docker image), thus we publish the container's `port 8080` to the `localhost`:
+For the purpose of the test. We are going to start the container that has a web service running inside it built using Node/Express. In order to access this service within the container from the outside, as we are about to do using `curl`, port mapping needs to be done next. As a result, we can now access the web service inside docker by first reaching an IP port on `localhost`, which subsequently forwards the request to the docker container's designated port.
+In our example, the `Action` container exposes `port 8080` (see the Dockerfile for the associated Docker image), thus we publish the container's `port 8080` to the `localhost` (here, `port 3008` on `localhost` is chosen arbitrarily, as long as the port is not already assigned for something else):
 ```
 docker run --publish 3008:8080 -i -t action-nodejs-v18:latest
 ```
+A simpler way is to map `port 80` on `localhost` to the container's `port 8080`. The port number assigned to the HTTP protocol is `80` Since we will be sending actions against the runtime using HTTP, using this number will allow us to omit the port in the request later. Without loss of generality, the following examples will use the arbitrarily chosen `port 3008`
 
 ## Testing
 This example has prepared a `helloworld.json` file to post using `curl`.
+```json
+{
+  "value": {
+    "name" : "nodejs-helloworld",
+    "main" : "main",
+    "binary": false,
+    "code" : "function main() {return {payload: 'Hello World!'};}"
+  }
+}
+```
+The json file contains a simple JavaScript function, which is the actual payload.
 
 ### Initialze the Runtime
-Initialize the runtime with by invoking the ```/init``` endpoint.
+Before issuing the action against the runtime, we first initialize the function with by invoking the ```/init``` endpoint.
 ```
 curl -H "Content-Type:application/json" -X POST --data '@openwhisk-runtime-nodejs/tests/src/test/standalone/helloworld/helloworld.json' http://localhost:3008/init
 
 {"OK":true}
 ```
+being the expected response.
+
+As mentioned above, if `port 80` on `localhost` was used, the command could simply be
+```
+curl -H "Content-Type:application/json" -X POST --data '@openwhisk-runtime-nodejs/tests/src/test/standalone/helloworld/helloworld.json' http://localhost/init
+```
 
 #### Run the function
 
-Execute the function using the ```/run``` endpoint.
+Invoke the function using the ```/run``` endpoint.
 
 ```
 curl -H ""Content-Type:application/json" -X POST --data '@openwhisk-runtime-nodejs/tests/src/test/standalone/helloworld/helloworld.json' http://localhost:3008/run
+```
 
+The JavaScript function in this example is one without arguments. Using the same json file as during initialization won't be a problem. Strictly speaking, we should have provided another json file with the arguments. In our case, it should simply be
+```json
+{
+   "value": {}
+}
+```
+The expected response should be
+```
 {"payload":"Hello World!"}
-```
+```
+Also the running container will print
+```
+XXX_THE_END_OF_A_WHISK_ACTIVATION_XXX
+```
+in the terminal