update

Author: gregvers

.gitignore

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+.DS_Store

helloworld/README.md

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-# Oracle Functions Hello World
+# Function Hello World
 
-Get started with Java, Nodejs, Python, Golang and Ruby functions on Oracle Functions
+This function returns the "Hello World" message or "Hello <name>" when you provide a name in the function call payload.
 
-- Pre-requisite - [Create Application](create-application.md)
-- [Java](java/README.md)
-- [Nodejs](node/README.md)
-- [Python](python/README.md)
-- [Golang](golang/README.md)
-- [Ruby](ruby/README.md)
+As you make your way through this tutorial, look out for this icon ![user input icon](./images/userinput.png).
+Whenever you see it, it's time for you to perform an action.
+
+
+## Pre-requisites
+1. Start by making sure all of your policies are correct from this [guide](https://docs.cloud.oracle.com/iaas/Content/Functions/Tasks/functionscreatingpolicies.htm?tocpath=Services%7CFunctions%7CPreparing%20for%20Oracle%20Functions%7CConfiguring%20Your%20Tenancy%20for%20Function%20Development%7C_____4)
+
+2. Have [Fn CLI setup with Oracle Functions](https://docs.cloud.oracle.com/iaas/Content/Functions/Tasks/functionsconfiguringclient.htm?tocpath=Services%7CFunctions%7CPreparing%20for%20Oracle%20Functions%7CConfiguring%20Your%20Client%20Environment%20for%20Function%20Development%7C_____0)
+
+
+## Create an Application to run your function
+You can use an application already created or create a new one using either the CLI or the OCI console.
+
+![user input icon](./images/userinput.png)
+
+### using the CLI
+```
+fn create app <app-name> --annotation oracle.com/oci/subnetIds='["<subnet-ocid>"]'
+```
+Get the OCID of the subnet in your VCN you wish to use.
+
+e.g.
+```
+fn create app myapp --annotation oracle.com/oci/subnetIds='["ocid1.subnet.oc1.phx.aaaaaaaacnh..."]'
+```
+
+### using the OCI console
+Log in to the [OCI console](https://console.us-phoenix-1.oraclecloud.com/) with your account, select the same region and compartment you specified when you configured the Fn CLI context.
+
+On the OCI console, navigate to Developer Services > Functions. Click `Create Application` and specify:
+- The name for the new application as *myapp*.
+- The VCN and subnet in which to run the function.
+
+Click `Create`.
+
+![](./images/create-application.png "Create Application")
+
+
+## Writing the code of function
+
+The [Python folder](./python) contains the files to deploy the HelloWorld function in Python:
+* the code of the function, [func.py](./python/func.py)
+* its dependencies, [requirements.txt](./python/requirements.txt)
+* the function metadata, [func.yaml](./python/func.yaml)
+
+The [Java folder](./java) contains the files to deploy the HelloWorld function in Java:
+* the code of the function, [src/main/java/com/example/fn/HelloFunction.java](./java/src/main/java/com/example/fn/HelloFunction.java)
+* its dependencies, [pom.xml](./java/pom.xml)
+* the function metadata, [func.yaml](./java/func.yaml)
+
+![user input icon](./images/userinput.png)
+
+You can also generation your own HelloWorld function files by running the following command from your terminal:
+
+```
+fn init --runtime <runtime-language> helloworld
+```
+
+where <runtime-language> is one of the supported runtime languages (currently go, java, node, and python are supported).
+
+For example:
+```
+fn init --runtime python helloworld
+```
+
+A directory called *helloworld* is created containing the necessary files to deploy the HelloWorld function.
+
+
+## Deploy the function
+
+![user input icon](./images/userinput.png)
+
+Change directory to the *helloworld* directory created in the previous step:
+
+```
+cd helloworld
+```
+
+If you did not generate your own function and you are deploying what is provided in this repo, change to either `Java` or `Python`.
+
+To deploy the function, run the following command:
+```
+fn -v deploy --app <your app name>
+```
+e.g.
+```
+fn -v deploy --app myapp
+```
+
+
+## Invoke the function
+
+![user input icon](./images/userinput.png)
+
+Invoke the *helloworld* function by entering:
+
+```
+fn invoke <your app name> helloworld
+```
+e.g. 
+```
+fn invoke myapp helloworld
+```
+
+The Python version displays `{"message":"Hello World!"}` and the Java version displays `Hello World!`
+
+You can also pass in a payload to invoke the function. 
+For Java, run:
+```
+echo -n "Bob" | fn invoke <your app name> helloworld
+```
+The `Hello Bob!` output is displayed.
+For Python, run:
+```
+echo -n '{"name":"Bob"}' | fn invoke <your app name> helloworld
+```
+The `{"message":"Hello Bob!"}` output is displayed.
+
+Congratulations! You've just created, deployed, and invoked the HelloWorld function using Oracle Functions!