docs: add instructions to install the CLI through Krew (#193)

# Description

[Retina is available in
Krew!](kubernetes-sigs/krew-index#3722)
Updates the docs with installation instructions using Krew.
Also updates the Helm chart installation instructions to fetch the
latest released version instead of hardcoding a version.

## Related Issue

related to #108 
provides a permanent fix for #163

---------

Signed-off-by: Evan Baker <[email protected]>
Co-authored-by: Jacques I Massa <[email protected]>

Author: rbtr

.goreleaser.yaml

@@ -22,7 +22,7 @@ builds:
       - windows
       - darwin
     ldflags:
-      - -X github.com/microsoft/retina/cli/cmd.Version={{.Version}}
+      - -X github.com/microsoft/retina/cli/cmd.Version=v{{.Version}}
     main: cli/main.go
 
 archives:

README.md

@@ -40,10 +40,12 @@ Retina has two major features:
 Retina can be installed using the Helm chart from GHCR:
 
 ```bash
+# Set the version to a specific version here or get latest version from GitHub API.
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
 helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
-    --version v0.0.2 \
-		--set image.tag=v0.0.2 \
-		--set operator.tag=v0.0.2 \
+    --version $VERSION \
+		--set image.tag=$VERSION \
+		--set operator.tag=$VERSION \
 		--set logLevel=info \
 		--set enabledPlugin_linux="\[dropreason\,packetforward\,linuxutil\,dns\]"
 ```
@@ -56,31 +58,25 @@ After Helm install, follow steps in [Using Prometheus and Grafana](https://retin
 
 #### Captures via CLI
 
-Currently, Retina CLI only supports Linux.
+The preferred way to install the Retina CLI using [Krew](https://krew.sigs.k8s.io/).
 
-- Option 1: Download from Release
-
-  Download the correct `kubectl-retina` package for your platform from the latest [Retina release](https://github.com/microsoft/retina/releases).
-  Feel free to move the binary to `/usr/local/bin/`, or add it to your `PATH` otherwise.
-
-- Option 2: Build from source
-
-  Requirements:
-
-  - go 1.21 or newer
+```bash
+kubectl krew install retina
+```
 
-  Clone the Retina repo and execute:
+Other installation options are documented in [CLI Installation](https://retina.sh/docs/installation/cli).
 
-  ```shell
-  go build -o bin/kubectl-retina cli/main.go
-  ```
+Verify installation:
 
-  and move bin/kubectl-retina in to your $PATH.
+```bash
+$ kubectl retina version
+v0.0.4 # or latest version
+```
 
-Execute Retina:
+To quickly start creating a capture:
 
-```shell
-kubectl-retina capture create --help
+```bash
+kubectl retina capture create --name <my-capture> --namespace <my-namespace> --selector <app=my-app>
 ```
 
 For further CLI documentation, see [Capture with Retina CLI](https://retina.sh/docs/captures/cli).
@@ -90,10 +86,11 @@ For further CLI documentation, see [Capture with Retina CLI](https://retina.sh/d
 Install Retina using Helm:
 
 ```bash
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
 helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
-    --version v0.0.2 \
-    --set image.tag=v0.0.2 \
-    --set operator.tag=v0.0.2 \
+    --version $VERSION \
+    --set image.tag=$VERSION \
+    --set operator.tag=$VERSION \
     --set image.pullPolicy=Always \
     --set logLevel=info \
     --set os.windows=true \

docs/installation/cli.md

@@ -4,23 +4,34 @@ Currently, Retina CLI supports Linux, Windows, and MacOS on x86_64 and ARM64 pla
 
 For CLI usage, see [Capture with Retina CLI](../captures/cli.md).
 
-## Option 1: Download from Release
+## Option 1: Install using Krew
 
-Download `kubectl-retina` from the latest [Retina release](https://github.com/microsoft/retina/releases).
-Feel free to move the binary to `/usr/local/bin/`, or add it to your `PATH` otherwise.
+Retina CLI is available as a [Krew plugin](https://krew.sigs.k8s.io/)! To install it, run:
+
+```bash
+kubectl krew install retina
+```
+
+## Option 2: Download the binary from the latest release on GitHub
+
+Download the `kubectl-retina` package for your platform from the latest [Retina release](https://github.com/microsoft/retina/releases/latest).
 
 ## Option 2: Build from source
 
 Building the CLI requires go1.21 or greater.
 
-To build the CLI simply with Go:
+To build the CLI simply and quickly with Go:
 
 ```bash
 go build -o bin/kubectl-retina cli/main.go
 ```
 
-To cross-compile for all supported platforms, use [GoReleaser](https://goreleaser.com/):
+The release pipeline uses [GoReleaser](https://goreleaser.com/), which is the recommended way to build the CLI.
+
+To build the CLI with GoReleaser:
 
 ```bash
-goreleaser build --snapshot --clean
+goreleaser build --snapshot --clean [--single-target]
 ```
+
+Note: --single-target is optional and can be used to build for the current platform only. Omit it to cross-compile for all supported platforms.

docs/installation/setup.md

@@ -6,28 +6,28 @@ Note: you can also run captures with just the [CLI](./cli.md).
 
 ## Installation
 
-When installing with helm, substitute the `version` and image `tag` arguments to the desired version, if different.
-
 ### Basic Mode
 
 ```shell
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
 helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
-    --version v0.0.2 \
+    --version $VERSION \
     --namespace kube-system \
-    --set image.tag=v0.0.2 \
-    --set operator.tag=v0.0.2 \
+    --set image.tag=$VERSION \
+    --set operator.tag=$VERSION \
     --set logLevel=info \
     --set enabledPlugin_linux="\[dropreason\,packetforward\,linuxutil\,dns\]"
 ```
 
 ### Basic Mode (with Capture support)
 
 ```shell
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
 helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
-    --version v0.0.2 \
+    --version $VERSION \
     --namespace kube-system \
-    --set image.tag=v0.0.2 \
-    --set operator.tag=v0.0.2 \
+    --set image.tag=$VERSION \
+    --set operator.tag=$VERSION \
     --set logLevel=info \
     --set image.pullPolicy=Always \
     --set logLevel=info \
@@ -43,11 +43,12 @@ helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
 See [Metric Modes](../metrics/modes.md).
 
 ```shell
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
 helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
-    --version v0.0.2 \
+    --version $VERSION \
     --namespace kube-system \
-    --set image.tag=v0.0.2 \
-    --set operator.tag=v0.0.2 \
+    --set image.tag=$VERSION \
+    --set operator.tag=$VERSION \
     --set image.pullPolicy=Always \
     --set logLevel=info \
     --set os.windows=true \
@@ -64,11 +65,12 @@ helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
 See [Metric Modes](../metrics/modes.md).
 
 ```shell
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
 helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
-    --version v0.0.2 \
+    --version $VERSION \
     --namespace kube-system \
-    --set image.tag=v0.0.2 \
-    --set operator.tag=v0.0.2 \
+    --set image.tag=$VERSION \
+    --set operator.tag=$VERSION \
     --set image.pullPolicy=Always \
     --set logLevel=info \
     --set os.windows=true \