add tekton results blog

Signed-off-by: Avinal Kumar <avinal.xlvii@gmail.com>

static/content/posts/blogs/hey-tekton-results.md

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 ---
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+title: Tekton Results to the Rescue
+date: 2023-03-16 20:47
+tags: [tekton, kubernetes, redhat, openshift, results]
+category: blogs
+image: "/images/tekton-results-wall.webp"
+description: Tekton Results aims to help users logically group CI/CD workload history and separate out long term result storage away from the Pipeline controller.
+---
+
+# Tekton Results to the Rescue
+
+What do you do with your Tekton Pipelines once it finishes? Depending on if it
+failed or passed, you may keep it to inspect the logs. For most of the users/organizations
+the simplest step is to keep the completed TaskRuns/PipelineRuns object on the
+cluster to retrieve the data later.
+
+Imagine having thousands of runs and although a single TaskRun object takes very
+small space compared to the scale of a production cluster, but these little
+things add up quickly, and soon your cluster will be burdened with objects that
+probably no one will ever revisit. The organization/user is keeping them
+just-in-case if they want to see the logs and other data later.
+
+Although in most of the cases there is a pruning policy that takes care of these
+objects. But there are multiple problems with this approach.
+
+- This type of storage is not reliable and very difficult to query.
+- If the scale is massive, this could lead to destabilization of the cluster.
+- If you have a pruning policy, the completed objects are cleaned, and you lose all the associated data as well.
+
+So, what is the solution, how can you save your pipelines' data without having to keep them on cluster?
+
+## Introducing Tekton Results
+
+As mentioned on the [project repository](https://github.com/tektoncd/results):
+
+> Tekton Results aims to help users logically group CI/CD workload history and separate out long term result storage away from the Pipeline controller. This allows you to:
+>
+> - Provide custom Result metadata about your CI/CD workflows not available in the Tekton TaskRun/PipelineRun CRDs (for example: post-run actions)
+> - Group related workloads together (e.g. bundle related TaskRuns and PipelineRuns into a single unit)
+> - Make long-term result history independent of the Pipeline CRD controller, letting you free up etcd resources for Run execution.
+
+In short, Tekton results archives the run data (called results) and logs to an
+external storage. Now you can safely prune completed TaskRuns/PipelineRuns and
+save run data and logs for a later visit. Let us see how actually Tekton Results
+works under the hood.
+
+### How Tekton Results Works?
+
+Tekton Results is composed of two main components.
+
+- A **watcher** to listen to creation/update of PipelineRuns or TaskRuns.
+- An **API Server** to query the persistent storage for data.
+
+In addition to that, Tekton Results needs a working database connection that can
+be a persistent storage on the same cluster or hosted externally such as RDS.
+If no external storage is attached, logs are also stored on a persistent storage
+on the cluster, you may use a S3 (or compatible) storage solution for that.
+
+The lifecycle of a *result* is as below:
+
+1. The first step is to create a Tekton PipelineRun or TaskRun.
+2. The Watcher listens for any changes in the TaskRun or PipelineRun.
+3. On change, Watcher updates (or creates) a corresponding `Record` or `Result` using the Results API.
+    Watcher adds annotations to the TaskRuns or PipelineRuns with proper identifiers. Watcher uses
+    these annotations to decide if the `Result` has been created/updated/finished or not.
+4. You can now query the Results data using the API. If the run state is incomplete yet, the response
+    from the API will indicate that as well via the status flag.
+5. Once the TaskRun/PipelineRun has been completed, you can safely prune the resource object.
+
+## Installing Tekton Results
+
+Installing Tekton Results is easy. You can use Kubernetes or OpenShift cluster, for this particular
+demonstration, I will be using a Kind cluster and a local database.
+
+### Prerequisites
+
+- [Kind](https://kind.sigs.k8s.io/docs/user/quick-start/#installation) for a local Kubernetes cluster.
+- [kubectl](https://kubernetes.io/docs/tasks/tools/#kubectl)
+- [curl](https://curl.se/download.html) for quering the API.
+- [OpenSSL](https://www.openssl.org/source/) for generating certificates.
+
+### Let's start
+
+1. Create a Kind Cluster
+
+    ```sh
+    kind create cluster --name tekton-results
+    kind export kubeconfig --name tekton-results
+    ```
+
+2. [Tekton Pipelines]() must be installed on the cluster. You can install it using the command below.
+
+    ```sh
+    kubectl apply --filename https://storage.googleapis.com/tekton-releases/pipeline/latest/release.yaml
+    ```
+
+3. Generate a database root password and store as a Kubernetes Secret. If you are using an external
+    database, prove the credential for the same. Here is a bare minimum requirement as YAML.
+
+    ```yaml
+    apiVersion: v1
+    kind: Secret
+    metadata:
+    name: tekton-results-postgres
+    namespace: tekton-pipelines
+    type: Opaque
+    data:
+    POSTGRES_USER: postgres
+    POSTGRES_PASSWORD: <your-password>
+    ```
+
+    You can directly use the command line as well:
+
+    ```sh
+    kubectl create secret generic tekton-results-postgres --namespace="tekton-pipelines" --from-literal=POSTGRES_USER=postgres --from-literal=POSTGRES_PASSWORD=$(openssl rand -base64 20)
+    ```
+
+4. Generate a cert/key pair. You may use any cert management software to generate this. You can even
+    use cluster generated certs.
+
+    ```sh
+    openssl req -x509 \
+    -newkey rsa:4096 \
+    -keyout key.pem \
+    -out cert.pem \
+    -days 365 \
+    -nodes \
+    -subj "/CN=tekton-results-api-service.tekton-pipelines.svc.cluster.local" \
+    -addext "subjectAltName = DNS:tekton-results-api-service.tekton-pipelines.svc.cluster.local"
+    ```
+
+5. Create another TLS Kubernetes Secret with the name `tekon-results-tls` to store the cert/key pair.
+
+    ```sh
+    kubectl create secret tls -n tekton-pipelines tekton-results-tls \
+    --cert=cert.pem \
+    --key=key.pem
+    ```
+
+6. Install Tekton Results
+
+    ```sh
+    kubectl apply -f https://storage.googleapis.com/tekton-releases/results/latest/release.yaml
+    ```
+
+7. You can check the status of the deployments using the below command. Do not worry
+    if some deployments show `CrashLoopBackOff`. Wait for some time, and
+    they should all be running.
+
+    ```sh
+    kubectl get pods -n tekton-pipelines --watch
+    ```
+
+Once all deployments are ready, we can start creating some TaskRuns/PipelineRuns. In the next part
+of this blog, I will explain how to retrieve data from Tekton Results. Happy Reading.
+
+## References
+
+- [Tekton Results](https://github.com/tektoncd/results)
+- [Tekton Pipelines](https://github.com/tektoncd/pipelines)

static/content/posts/blogs/hrt-interview-1.md

@@ -2,7 +2,7 @@
 title: HRT (Hudson River Trading) Systems Internship Interview Experience
 date: 2021-01-04 21:47
 tags: [HRT, hudsonrivertrading, interview, internship]
-category: blog
+category: blogs
 image: "/images/hrt-singapore.webp"
 ---