# istio-distributed-tracing-example

**Repository Path**: keren_chen/istio-distributed-tracing-example

## Basic Information

- **Project Name**: istio-distributed-tracing-example
- **Description**: https://github.com/snowdrop/istio-distributed-tracing-example.git
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2022-09-27
- **Last Updated**: 2022-09-27

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

= Istio Distributed Tracing Mission

== Purpose
Showcase Istio's Distributed Tracing via a (minimally) instrumented set of Spring Boot applications

== Prerequisites
. Openshift 3.10 cluster
. Istio 1.0.x installed on the aforementioned cluster using the link:https://github.com/Maistra/istio-operator[Istio Operator].
.. Follow link:https://github.com/Maistra/openshift-ansible/blob/maistra-0.1.0-ocp-3.1.0-istio-1.0.0/istio/Installation.md[these] instructions for more information about the Operator
. Login to the cluster with the *admin* user

== Environment preparation

Create a new project/namespace on the cluster. This is where your application will be deployed.

```bash
oc new-project <whatever valid project name you want>
```

In link:https://docs.openshift.com/container-platform/3.11/servicemesh-install/servicemesh-install.html#configuring-security-constraints-for-application-service-accounts[OpenShift] each service account must be granted permissions with the anyuid and privileged Security Context Constraints (SCC) to enable the sidecars to run correctly.

```bash
oc adm policy add-scc-to-user anyuid -z default -n <whatever valid project name you want>
oc adm policy add-scc-to-user privileged -z default -n <whatever valid project name you want>
```

== Build and deploy the application

=== With Fabric8 Maven Plugin (FMP)
Execute the following command to build the project and deploy it to OpenShift:
```bash
mvn clean fabric8:deploy -Popenshift
```
Configuration for FMP may be found both in pom.xml and `src/main/fabric8` files/folders.

This configuration is used to define service names and deployments that control how pods are labeled/versioned on the OpenShift cluster. Labels and versions are key concepts for creating load-balanced or multi-versioned pods in a service.


=== With Source to Image build (S2I)
Run the following commands to apply and execute the OpenShift templates that will configure and deploy the applications:
```bash
    find . | grep openshiftio | grep application | xargs -n 1 oc apply -f

    oc new-app --template=istio-distributed-tracing-example-greeting-service -p SOURCE_REPOSITORY_URL=https://github.com/snowdrop/istio-distributed-tracing-example -p SOURCE_REPOSITORY_REF=master -p SOURCE_REPOSITORY_DIR=spring-boot-istio-distributed-tracing-greeting-service
    oc new-app --template=istio-distributed-tracing-example-cute-name-service -p SOURCE_REPOSITORY_URL=https://github.com/snowdrop/istio-distributed-tracing-example -p SOURCE_REPOSITORY_REF=master -p SOURCE_REPOSITORY_DIR=spring-boot-istio-distributed-tracing-cute-name-service
```

= Use Cases
== Access the application via the Istio ingress-gateway
. Create a RouteRule to forward traffic from istio-ingress to the demo application
+
```bash
    oc create -f rules/greeting-gateway.yml
```
. Access the application
+
Run the following command to determine the appropriate URL to access our demo. Make sure you access the url with the HTTP scheme. HTTPS is NOT enabled by default:
+
```bash
echo http://$(oc get route istio-ingressgateway -o jsonpath='{.spec.host}{"\n"}' -n istio-system)/greeting/
```
+
The result of the above command is the istio-system istio-ingress URL, appended with the RouteRule path. Open this URL in your a web browser.
. Follow the instructions in the application UI

== View application traces
. Access the Jaeger tracing dashboard
+
The traces from the invocation of the two endpoints should look like the following:
+
image::spring-boot-istio-distributed-tracing-greeting-service/src/main/resources/static/traces.jpg[]
+
Note that it could take a few seconds for all the spans to be collected and presented in a trace that matches the picture above


== Undeploy the application

=== With Fabric8 Maven Plugin (FMP)
```bash
mvn fabric8:undeploy
```

=== With Source to Image build (S2I)
```bash
oc delete all --all
oc delete ingress --all
find . | grep openshiftio | grep application | xargs -n 1 oc delete -f
```

=== Remove the namespace
This will delete the project from the OpenShift cluster
```bash
oc delete project <your project name>
```

== Integration tests

To run integration tests, create a new namespace and run maven job
```bash
oc new-project <project-name>
mvn clean verify -Popenshift,openshift-it
```