https://github.com/gilluan/java-basic-lambda
java basic lambda sample with h2
https://github.com/gilluan/java-basic-lambda
Last synced: 3 months ago
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java basic lambda sample with h2
- Host: GitHub
- URL: https://github.com/gilluan/java-basic-lambda
- Owner: gilluan
- Created: 2021-03-25T03:05:24.000Z (about 4 years ago)
- Default Branch: main
- Last Pushed: 2021-03-25T03:05:50.000Z (about 4 years ago)
- Last Synced: 2025-01-21T23:31:31.548Z (5 months ago)
- Language: Java
- Size: 2.28 MB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# Basic function with minimal dependencies (Java)
The project source includes function code and supporting resources:
- `src/main` - A Java function.
- `src/test` - A unit test and helper classes.
- `template.yml` - An AWS CloudFormation template that creates an application.
- `build.gradle` - A Gradle build file.
- `pom.xml` - A Maven build file.
- `1-create-bucket.sh`, `2-deploy.sh`, etc. - Shell scripts that use the AWS CLI to deploy and manage the application.
Use the following instructions to deploy the sample application.
# Requirements
- [Java 8 runtime environment (SE JRE)](https://www.oracle.com/java/technologies/javase-downloads.html)
- [Gradle 5](https://gradle.org/releases/) or [Maven 3](https://maven.apache.org/docs/history.html)
- The Bash shell. For Linux and macOS, this is included by default. In Windows 10, you can install the [Windows Subsystem for Linux](https://docs.microsoft.com/en-us/windows/wsl/install-win10) to get a Windows-integrated version of Ubuntu and Bash.
- [The AWS CLI](https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-install.html) v1.17 or newer.
If you use the AWS CLI v2, add the following to your [configuration file](https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-files.html) (`~/.aws/config`):
```
cli_binary_format=raw-in-base64-out
```
This setting enables the AWS CLI v2 to load JSON events from a file, matching the v1 behavior.
# Setup
Download or clone this repository.
$ git clone https://github.com/awsdocs/aws-lambda-developer-guide.git
$ cd aws-lambda-developer-guide/sample-apps/java-basic
To create a new bucket for deployment artifacts, run `1-create-bucket.sh`.
java-basic$ ./1-create-bucket.sh
make_bucket: lambda-artifacts-a5e4xmplb5b22e0d
# Deploy
To deploy the application, run `2-deploy.sh`.
java-basic$ ./2-deploy.sh
BUILD SUCCESSFUL in 1s
Successfully packaged artifacts and wrote output template to file out.yml.
Waiting for changeset to be created..
Successfully created/updated stack - java-basic
This script uses AWS CloudFormation to deploy the Lambda functions and an IAM role. If the AWS CloudFormation stack that contains the resources already exists, the script updates it with any changes to the template or function code.
You can also build the application with Maven. To use maven, add `mvn` to the command.
java-basic$ ./2-deploy.sh mvn
[INFO] Scanning for projects...
[INFO] -----------------------< com.example:java-basic >-----------------------
[INFO] Building java-basic-function 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
...
# Test
To invoke the function, run `3-invoke.sh`.
java-basic$ ./3-invoke.sh
{
"StatusCode": 200,
"ExecutedVersion": "$LATEST"
}
"200 OK"
Let the script invoke the function a few times and then press `CRTL+C` to exit.
The application uses AWS X-Ray to trace requests. Open the [X-Ray console](https://console.aws.amazon.com/xray/home#/service-map) to view the service map.
Choose a node in the main function graph. Then choose **View traces** to see a list of traces. Choose any trace to view a timeline that breaks down the work done by the function.
# Configure Handler Class
By default, the function uses a handler class named `Handler` that takes a map as input and returns a string. The project also includes handlers that use other input and output types. These are defined in the following files under src/main/java/example:
- `Handler.java` – Takes a `Map` as input.
- `HandlerInteger.java` – Takes an `Integer` as input.
- `HandlerList.java` – Takes a `List` as input.
- `HandlerDivide.java` – Takes a `List` with two integers as input.
- `HandlerStream.java` – Takes an `InputStream` and `OutputStream` as input.
- `HandlerString.java` – Takes a `String` as input.
- `HandlerWeatherData.java` – Takes a custom type as input.
To use a different handler, change the value of the Handler setting in the application template (`template.yml` or `template-mvn.yaml`). For example, to use the list handler:
Properties:
CodeUri: build/distributions/java-basic.zip
Handler: example.HandlerList
Deploy the change, and then use the invoke script to test the new configuration. For handlers, that don't take a JSON object as input, pass the type (`string`, `int` or `list`) as an argument to the invoke script.
./3-invoke.sh list
{
"StatusCode": 200,
"ExecutedVersion": "$LATEST"
}
9979
# Cleanup
To delete the application, run `4-cleanup.sh`.
java-basic$ ./4-cleanup.sh