index.md

title	description
Homepage	AWS Lambda Powertools Java

Powertools is a suite of utilities for AWS Lambda Functions that makes tracing with AWS X-Ray, structured logging and creating custom metrics asynchronously easier.

!!! tip "Looking for a quick run through of the core utilities?" Check out this detailed blog post with a practical example.

Tenets

This project separates core utilities that will be available in other runtimes vs general utilities that might not be available across all runtimes.

• AWS Lambda only – We optimise for AWS Lambda function environments and supported runtimes only. Utilities might work with web frameworks and non-Lambda environments, though they are not officially supported.
• Eases the adoption of best practices – The main priority of the utilities is to facilitate best practices adoption, as defined in the AWS Well-Architected Serverless Lens; all other functionality is optional.
• Keep it lean – Additional dependencies are carefully considered for security and ease of maintenance, and prevent negatively impacting startup time.
• We strive for backwards compatibility – New features and changes should keep backwards compatibility. If a breaking change cannot be avoided, the deprecation and migration process should be clearly defined.
• We work backwards from the community – We aim to strike a balance of what would work best for 80% of customers. Emerging practices are considered and discussed via Requests for Comment (RFCs)
• Idiomatic – Utilities follow programming language idioms and language-specific best practices.

Install

Powertools dependencies are available in Maven Central. You can use your favourite dependency management tool to install it

• Maven
• Gradle

Quick hello world examples using SAM CLI

You can use SAM to quickly setup a serverless project including AWS Lambda Powertools Java.

  sam init --location gh:aws-samples/cookiecutter-aws-sam-powertools-java

For more information about the project and available options refer to this repository

=== "Maven"

```xml hl_lines="3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55" 
<dependencies>
    ...
    <dependency>
        <groupId>software.amazon.lambda</groupId>
        <artifactId>powertools-tracing</artifactId>
        <version>1.7.1</version>
    </dependency>
    <dependency>
        <groupId>software.amazon.lambda</groupId>
        <artifactId>powertools-logging</artifactId>
        <version>1.7.1</version>
    </dependency>
    <dependency>
        <groupId>software.amazon.lambda</groupId>
        <artifactId>powertools-metrics</artifactId>
        <version>1.7.1</version>
    </dependency>
    ...
</dependencies>
...
<!-- configure the aspectj-maven-plugin to compile-time weave (CTW) the aws-lambda-powertools-java aspects into your project -->
<build>
    <plugins>
        ...
        <plugin>
             <groupId>org.codehaus.mojo</groupId>
             <artifactId>aspectj-maven-plugin</artifactId>
             <version>1.14.0</version>
             <configuration>
                 <source>1.8</source>
                 <target>1.8</target>
                 <complianceLevel>1.8</complianceLevel>
                 <aspectLibraries>
                     <aspectLibrary>
                         <groupId>software.amazon.lambda</groupId>
                         <artifactId>powertools-tracing</artifactId>
                     </aspectLibrary>
                     <aspectLibrary>
                         <groupId>software.amazon.lambda</groupId>
                         <artifactId>powertools-logging</artifactId>
                     </aspectLibrary>
                     <aspectLibrary>
                         <groupId>software.amazon.lambda</groupId>
                         <artifactId>powertools-metrics</artifactId>
                     </aspectLibrary>
                 </aspectLibraries>
             </configuration>
             <executions>
                 <execution>
                     <goals>
                         <goal>compile</goal>
                     </goals>
                 </execution>
             </executions>
        </plugin>
        ...
    </plugins>
</build>
```

=== "Gradle"

```groovy
plugins{
    id 'java'
    id 'aspectj.AspectjGradlePlugin' version '0.0.6'
}
repositories {
    jcenter()
}
dependencies {
    implementation 'software.amazon.lambda:powertools-tracing:1.7.1'
    aspectpath 'software.amazon.lambda:powertools-tracing:1.7.1'
    implementation 'software.amazon.lambda:powertools-logging:1.7.1'
    aspectpath 'software.amazon.lambda:powertools-logging:1.7.1'
    implementation 'software.amazon.lambda:powertools-metrics:1.7.1'
    aspectpath 'software.amazon.lambda:powertools-metrics:1.7.1'
}
```
**Note:**

Please add `aspectjVersion = '1.9.6'` to the `gradle.properties` file. The aspectj plugin works at the moment with gradle 5.x only if
you are using `java 8` as runtime. Please refer to [open issue](https://github.com/awslabs/aws-lambda-powertools-java/issues/146) for more details.

Environment variables

!!! info Explicit parameters take precedence over environment variables.

Environment variable	Description	Utility
POWERTOOLS_SERVICE_NAME	Sets service name used for tracing namespace, metrics dimension and structured logging	All
POWERTOOLS_METRICS_NAMESPACE	Sets namespace used for metrics	Metrics
POWERTOOLS_LOGGER_SAMPLE_RATE	Debug log sampling	Logging
POWERTOOLS_LOG_LEVEL	Sets logging level	Logging
POWERTOOLS_TRACER_CAPTURE_RESPONSE	Enables/Disables tracing mode to capture method response	Tracing
POWERTOOLS_TRACER_CAPTURE_ERROR	Enables/Disables tracing mode to capture method error	Tracing