PCF Metrics Spring Tracer Example

This is a Spring Boot repository with three apps: shopping-cart, orders, and payments. These apps use Spring Cloud Sleuth to trace the calls between them. The traces can then be viewed in PCF-Metrics.

Creating your own tracer apps

Most of the app code is standard Spring Boot application code independent of tracing.

To add tracing the following steps are neccesary:

• Each app should have the compile('org.springframework.cloud:spring-cloud-starter-sleuth') dependency in its build.gradle.

• Each SpringBootApplication should have the following snippet:

@Bean
public RestTemplate restTemplate() {
    return new RestTemplate();
}

This allows sleuth to determine which RestTemplate to insert itself into.

• Optionally, to see the parent span id in the app logs, the following line can be added to application.properties:

logging.pattern.level: "%clr(%5p) %clr([${spring.application.name:-},%X{X-B3-TraceId:-},%X{X-B3-SpanId:-},%X{X-B3-ParentSpanId:-},%X{X-Span-Export:-}]){yellow}"

Parent Span Id will show up in the router logs even without this property.

Using the example apps

DEPLOY

To use the script, you must login as a user that has the ability to assign space permissions and make spaces. It will create a given shopping-cart, orders, and payments app that can be used to preview an example trace.

To deploy, use the script ./scripts/deploy.sh. Set the SUFFIX ENV var to a unique identifier for your tracer applications.

For example

cf login
SUFFIX=test ./scripts/deploy.sh

CURL APPS

Curl the /checkout endpoint for the given shopping cart app.

For example

curl shopping-cart-test.cfapps.io/checkout

CLEANUP

To cleanup, use the script ./scripts/cleanup.sh. Set the SUFFIX ENV var to the same identifier used for deployment.

For example

cf login
SUFFIX=test ./scripts/cleanup.sh

Viewing in PCF-Metrics

To view the trace in PCF-Metrics, go to the shopping-cart app in PCF-Metrics. Find the log corresponding to the /checkout endpoint and click the 'View in Trace Explorer' icon.

For example