new process to integrate AI to existing project (#158)

## Purpose
<!-- Describe the intention of the changes being proposed. What problem
does it solve or functionality does it add? -->
* ...

## Does this introduce a breaking change?
<!-- Mark one with an "x". -->
```
[ ] Yes
[ ] No
```

## Pull Request Type
What kind of change does this Pull Request introduce?

<!-- Please check the one that applies to this PR using "x". -->
```
[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:
```

## How to Test
*  Get the code

```
git clone [repo-address]
cd [repo-name]
git checkout [branch-name]
npm install
```

* Test the code
<!-- Add steps to run the tests suite and/or manually test -->
```
```

## What to Check
Verify that the following are valid
* ...

## Other Information
<!-- Add any other helpful information that may be needed here. -->

Author: sonwan2020

docs/05_lab_openai/05_openai.md

@@ -69,12 +69,12 @@ We utilize the `Github Copilot Chat` extension in VSCode to help us to initial t
    mkdir spring-petclinic-chat-service
 
    curl https://start.spring.io/starter.tgz \
-   -d dependencies=web,cloud-eureka,cloud-config-client,actuator,lombok,spring-ai-azure-openai \
-   -d bootVersion=3.3.6 -d name=chat-service -d type=maven-project \
-   -d jvmVersion=17 -d language=java -d packaging=jar \
-   -d groupId=org.springframework.samples.petclinic -d artifactId=chat-service \
-   -d description="Spring Petclinic Chat Service" \
-   | tar -xzvf - -C spring-petclinic-chat-service
+       -d dependencies=web,cloud-eureka,cloud-config-client,actuator,lombok,spring-ai-azure-openai \
+       -d bootVersion=3.3.6 -d name=chat-service -d type=maven-project \
+       -d jvmVersion=17 -d language=java -d packaging=jar \
+       -d groupId=org.springframework.samples.petclinic -d artifactId=chat-service \
+       -d description="Spring Petclinic Chat Service" \
+       | tar -xzvf - -C spring-petclinic-chat-service
    ```
 
    We may open the new application in VSCode to next operations.
@@ -98,7 +98,8 @@ We utilize the `Github Copilot Chat` extension in VSCode to help us to initial t
    Here we use the latest test code from Spring AI as part of the prompt. Download the latest chat client sample to your local environment:
 
    ```bash
-   wget https://raw.githubusercontent.com/spring-projects/spring-ai/refs/heads/main/models/spring-ai-azure-openai/src/test/java/org/springframework/ai/azure/openai/AzureOpenAiChatClientIT.java -P spring-petclinic-chat-service/src/main/resources/
+   IT_FILE="https://raw.githubusercontent.com/spring-projects/spring-ai/refs/heads/1.0.0-M4/models/spring-ai-azure-openai/src/test/java/org/springframework/ai/azure/openai/AzureOpenAiChatClientIT.java"
+   wget $IT_FILE -P spring-petclinic-chat-service/src/main/resources/
    ```
 
    Open the `Github Copilot Chat` window and drag the downloaded file into the chat window. And input the prompt:
@@ -221,17 +222,17 @@ We utilize the `Github Copilot Chat` extension in VSCode to help us to initial t
    @Data
    public class Owner implements Serializable {
 
-   private Integer id;
+       private Integer id;
 
-   private String firstName;
+       private String firstName;
 
-   private String lastName;
+       private String lastName;
 
-   private String address;
+       private String address;
 
-   private String city;
+       private String city;
 
-   private String telephone;
+       private String telephone;
    }
    ```
 
@@ -303,7 +304,7 @@ We utilize the `Github Copilot Chat` extension in VSCode to help us to initial t
 
    ```bash
    az containerapp update --name $APP_NAME --resource-group $RESOURCE_GROUP \
-    --source ./spring-petclinic-$APP_NAME
+       --source ./spring-petclinic-$APP_NAME
    ```
 
    - Verify the new RAG empowered AI bot about owners.

docs/05_lab_openai/05_openai_existing.md

@@ -0,0 +1,336 @@
+---
+title: 'Integrate AI to existing project'
+layout: default
+nav_order: 4
+parent: 'Lab 5: Integrate with Azure OpenAI'
+---
+
+# Integrate AI into your existing project
+
+In this chapter, we will learn how to create AI Java applications using Azure OpenAI and Spring AI.
+
+Start from a simple spring boot application, we will add AI components to the project and leverage AI to integrate with existing the petclinic solution we deployed in this lab.
+
+# Step by step guide
+
+1. We have simple sample saved in the tools directory, copy it under the folder `spring-petclinic-microservices`:
+
+   ```bash
+   cp -r ../tools/spring-petclinic-chat-service .
+   ```
+
+1. Open the chat-service project in VSCode
+
+   ```bash
+   code spring-petclinic-chat-service
+   ```
+
+1. In the VSCode IDE, make sure you have extension `Github Copilot Chat` installed, and login to Copilot with your github account.
+
+   Open the Github Copilot Chat Window, you can ask copliot in the "Ask Copilot" input box.
+
+1. Create a file for your system prompt.
+
+   Create file `src/main/resources/prompts/system-message.st` with content
+
+   ```text
+   You are a chatbot good at telling jokes.
+   ```
+
+1. Ask Copilot to create code for open AI integration.
+
+   Click the file `src/main/resources/AzureOpenAiChatClientIT.java`, and input the following prompt to "Ask Copilot":
+
+   ```text
+   Refer to the sample file named "AzureOpenAIChatClientIT.java", add a new ChatController with POST endpoint at '/chatclient' to the chat-service project:
+   * Use ChatClient to do the chat completion with Azure OpenAI Endpoint
+   * Use User Prompt from file "resources/prompts/system-message.st", do not use method getPath()
+   * The input of the endpoint '/chatclient' is a string from the request
+   * The output of the endpoint '/chatclient' is a string returned by openAI
+   * Use a configure file "ChatConfigure.java" file to init OpenAI ChatClient with Azure OpenAI Endpoint and API Key
+   ```
+
+   You will see output like:
+
+   ![lab 5 copilot generate code 1](../../images/copilot-gen-code-1.png)
+
+   ![lab 5 copilot generate code 2](../../images/copilot-gen-code-2.png)
+
+1. Follow the steps to make changes to the project.
+
+   In the VSCode terminal (current directory `spring-petclinic-chat-service`), run maven command to build the project:
+
+   ```bash
+   mvn clean package
+   ```
+
+   Fix the erorrs if there are any.
+
+1. Verify the chat endpoint.
+
+   - In the VSCode terminal, set the endpoint and api-key of your open ai instance, and run the app:
+
+   ```bash
+   export AZURE_OPENAI_API_KEY="<OPENAI-API-KEY>"
+   export AZURE_OPENAI_ENDPOINT="<OPENAI-ENDPOINT>"
+
+   mvn spring-boot:run
+   ```
+
+   Ignore the warnings on `c.n.discovery.InstanceInfoReplicator`.
+
+   - In your commandline environment, verify the '/chatclient' endpoint with simple command:
+
+   ```bash
+   curl -XPOST http://localhost:8080/chatclient -d 'Hi, tell a joke'
+   ```
+
+   You will get a joke generated by OpenAI. Congratulations!
+
+1. Deploy the `chat-service` to your Container Apps Environment.
+
+   In your commandline environment (current directory `spring-petclinic-microservices`), run:
+
+   ```bash
+   APP_NAME=chat-service
+
+   AZURE_OPENAI_API_KEY="<AZURE-OPENAI-API-KEY>"
+   AZURE_OPENAI_ENDPOINT="<AZURE-OPENAI-ENDPOINT>"
+
+   cp -f ../tools/Dockerfile ./spring-petclinic-$APP_NAME/Dockerfile
+   az containerapp create \
+       --name $APP_NAME \
+       --resource-group $RESOURCE_GROUP \
+       --environment $ACA_ENVIRONMENT \
+       --source ./spring-petclinic-$APP_NAME \
+       --registry-server $MYACR.azurecr.io \
+       --registry-identity $APPS_IDENTITY_ID \
+       --ingress external \
+       --target-port 8080 \
+       --min-replicas 1 \
+       --max-replicas 1 \
+       --env-vars AZURE_OPENAI_API_KEY="$AZURE_OPENAI_API_KEY" AZURE_OPENAI_ENDPOINT="$AZURE_OPENAI_ENDPOINT" \
+       --bind $JAVA_EUREKA_COMP_NAME \
+       --runtime java
+   ```
+
+   In your browser navigate to the [Azure portal](http://portal.azure.com) and find the container app `chat-service`. Check the details.
+
+   Verify chat-service in Azure Container Apps.
+
+   ```bash
+   CHAT_URL=$(az containerapp show \
+       --resource-group $RESOURCE_GROUP \
+       --name $APP_NAME \
+       --query properties.configuration.ingress.fqdn \
+       -o tsv)
+
+   curl -XPOST https://$CHAT_URL/chatclient -d 'Hi, tell a joke'
+   ```
+
+1. Function Calling with SpringAI
+
+   In this section, we will implement a basic RAG (Retrieval-Augmented Generation) pattern using Spring AI. The Retrieval-Augmented Generation (RAG) pattern is an industry standard approach to building applications that use large language models to reason over specific or proprietary data that is not already known to the large language model. This is critical because Azure Open AI model that we integrated in the previous step don't know anything about the PetClinic application. Refer to [Spring AI FunctionCallback API](https://docs.spring.io/spring-ai/reference/1.0/api/function-callback.html) for more information.
+
+   {: .note }
+   The Spring AI API is under development and the interface may change time to time. At this moment, we are using the API version `1.0.0-M4` in this sample.
+
+   In this sample, we will implement a FunctionCallback interface for AI to get the owners information from existing petclinic solution.
+
+   - Create a new `Owner.java` for owner details.
+
+   ```java
+   package org.springframework.samples.petclinic.chat_service;
+
+   import lombok.Data;
+
+   import java.io.Serializable;
+
+   @Data
+   public class Owner implements Serializable {
+
+       private Integer id;
+
+       private String firstName;
+
+       private String lastName;
+
+       private String address;
+
+       private String city;
+
+       private String telephone;
+   }
+   ```
+
+   - Create a new file `OwnerService.java` to retrieve owner info from `api-gateway`.
+
+   ```java
+   package org.springframework.samples.petclinic.chat_service;
+
+   import java.util.List;
+
+   import org.springframework.core.ParameterizedTypeReference;
+   import org.springframework.http.HttpMethod;
+   import org.springframework.stereotype.Service;
+   import org.springframework.web.client.RestTemplate;
+
+   @Service
+   public class OwnerService {
+
+       public List<Owner> getOwners() {
+
+           RestTemplate restTemplate = new RestTemplate();
+           var responseEntity = restTemplate.exchange(
+                   "http://api-gateway/api/customer/owners",
+                   HttpMethod.GET,
+                   null,
+                   new ParameterizedTypeReference<List<Owner>>() {
+                   });
+
+           List<Owner> owners = responseEntity.getBody();
+           return owners;
+       }
+   }
+   ```
+
+   - Add FunctionCallbacks to chat client.
+
+     First Add an attribute to ChatController"
+
+     ```java
+     @Autowired
+     private OwnerService ownerService;
+     ```
+
+     Add Functions to chat client. The new code segment would like, see the `functions` part.
+
+     ```java
+         ChatResponse response = this.chatClient.prompt()
+                  .system(s -> s.text(systemText))
+                  .user(userPrompt)
+                  .functions(FunctionCallback.builder()
+                           .description("list all owners")
+                           .method("getOwners")
+                           .targetObject(ownerService)
+                           .build())
+                  .call()
+                  .chatResponse();
+     ```
+
+     Fix the `import` issues with the help of VSCode.
+
+   - Rebuild the project in the VSCode termimal window (current directory spring-petclinic-chat-service):
+
+   ```bash
+   mvn clean package -DskipTests
+   ```
+
+   - Update the chat-service in your commandline window (current directory spring-petclinic-microservices):
+
+   ```bash
+   az containerapp update --name $APP_NAME --resource-group $RESOURCE_GROUP \
+       --source ./spring-petclinic-$APP_NAME
+   ```
+
+   Verify the AI integrated with spring petclinic output:
+
+   ```bash
+   curl -XPOST https://$CHAT_URL/chatclient -d 'list the names of the owners'
+
+   curl -XPOST https://$CHAT_URL/chatclient -d 'list the owners from Madison'
+   ```
+
+   You may create more owners in the api-gateway page and ask more questions on the owners. Note, here we only implemented the owner function.
+
+1. Here we have finished the first function for AI component to communicate with the existing system. Future more:
+
+   - You may add more functions to empower the AI strenght. Just like the getOwners sample.
+   - You may integration a chatbox in the api-gateway page. see [Chatbox in api-gateway](#optional-integrate-the-chat-client-into-api-gateway).
+
+# (Optional) Integrate the chat client into api-gateway
+
+1. Update service `api-gateway` to add a new chat window.
+
+   - Add new route entry for `chat-service`. Note this name will be used later. Open file `spring-petclinic-api-gateway/src/main/resources/application.yml` and append new entry like below:
+
+    ```yml
+           - id: chat-service
+             uri: lb://chat-service
+             predicates:
+               - Path=/api/chat/**
+             filters:
+               - StripPrefix=2
+     ```
+
+   - Add chatbox for api gateway
+
+   ```bash
+   git apply -f ../tools/api-gateway-chatbox.patch
+   ```
+
+   - Rebuild the api-gateway project and update the container app.
+
+   ```bash
+   APP_NAME=api-gateway
+   mvn clean package -DskipTests -pl spring-petclinic-$APP_NAME
+   az containerapp update --name $APP_NAME --resource-group $RESOURCE_GROUP \
+       --source ./spring-petclinic-$APP_NAME
+   ```
+
+   - Check the new chatbox in the petclinic page.
+
+   ```bash
+   api_gateway_FQDN=$(az containerapp show \
+     --resource-group $RESOURCE_GROUP \
+     --name $APP_NAME \
+     --query properties.configuration.ingress.fqdn \
+      -o tsv)
+
+   echo https://$api_gateway_FQDN
+   ```
+
+   Open the api-gateway url and there is a chatbox at the right bottom corner.
+
+   ![lab 5 api-gateway new chat box](../../images/api-gateway-chatbox.png)
+
+1. Verify the new RAG empowered AI bot about owners.
+
+   ![lab 5 open-ai-rag-bot](../../images/open-ai-rag-bot.png)
+
+# (Optional) Prepare the simple project
+
+1. Create a project from [spring initializr](https://start.spring.io/):
+
+   ```bash
+   curl https://start.spring.io/starter.tgz \
+       -d dependencies=web,cloud-eureka,actuator,lombok,spring-ai-azure-openai \
+       -d name=chat-service -d type=maven-project \
+       -d jvmVersion=17 -d language=java -d packaging=jar \
+       -d groupId=org.springframework.samples.petclinic -d artifactId=chat-service \
+       -d description="Spring Petclinic Chat Service" \
+       | tar -xzvf - -C spring-petclinic-chat-service
+   ```
+
+1. Update `application.properties` to `application.yml`
+
+   ```yml
+   spring:
+     application:
+       name: chat-service
+   ```
+
+1. Version
+
+   Verify the version of spring-ai is `1.0.0-M4`
+
+   Download the template file from branch `1.0.0.4`
+
+   ```bash
+   IT_FILE="https://raw.githubusercontent.com/spring-projects/spring-ai/refs/heads/1.0.0-M4/models/spring-ai-azure-openai/src/test/java/org/springframework/ai/azure/openai/AzureOpenAiChatClientIT.java"
+   wget $IT_FILE -P spring-petclinic-chat-service/src/main/resources/
+   ```
+
+1. Enable Eureka Client in class `ChatServiceApplication`:
+
+   ![lab 5 eureka client](../../images/open-ai-eureka-client.png)