ADR for require no maintenance to keep bootstrapping cli up to date

docs/adrs/0026-require-no-maintenance-to-keep-bootstrapping-cli-up-to-date.md

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+# 26. require no maintenance to keep bootstrapping cli up to date
+
+Date: 2023-12-13
+
+## Status
+
+Provisional
+
+## Context
+
+Currently, CLI bootstrapping creates and manages WGE values [here](https://github.com/weaveworks/weave-gitops-enterprise/blob/d27d52cf1053d194a40e7652a570d810db552613/pkg/bootstrap/steps/install_wge.go#L49-L124). This means any update / breaking change happens to WGE values
+will lead to degraded bootstrapping process for users and maintaining it will require extra cost. Values should be kept up to date accordingly when they change in the WGE. 
+
+## Decision
+
+### Options
+
+#### option a) Fetching the values file from the corresponding version
+
+example response for fetching the chart from [wge charts url](https://charts.dev.wkp.weave.works/releases/charts-v3)
+
+```yaml
+apiVersion: v1
+entries:
+  mccp:
+  - apiVersion: v2
+    appVersion: 1.16.0
+    created: "2023-12-11T13:29:39.19014457Z"
+    dependencies:
+    - condition: cluster-controller.enabled
+      name: cluster-controller
+      repository: file://../cluster-controller
+      version: 1.0.0
+    - condition: templates-controller.enabled
+      name: templates-controller
+      repository: file://../templates-controller
+      version: 0.3.0
+   .
+   .
+   .
+   .
+    description: A Helm chart for Kubernetes
+    digest: 8d7bab57fd4a1e87112ff950c3b9f65d26df968006d7968af3d5abec843faa79
+    name: mccp
+    type: application
+    urls:
+    - https://s3.us-east-1.amazonaws.com/weaveworks-wkp/releases/charts-v3/mccp-0.38.1.tgz
+    version: 0.38.1
+```
+
+Example url for `v0.38.1` version: `https://s3.us-east-1.amazonaws.com/weaveworks-wkp/releases/charts-v3/mccp-0.38.1.tgz`
+
+By downloading and uncompressing this file you will have the values file corresponding to the downloaded version
+
+Example for `v0.38.1` `mccp/values.yaml`
+
+```yaml
+# Default values for mccp.
+# This is a YAML-formatted file.
+# Declare variables to be passed into your templates.
+
+imagePullSecrets: []
+nameOverride: ""
+fullnameOverride: ""
+
+images:
+  clustersService: docker.io/weaveworks/weave-gitops-enterprise-clusters-service:v0.38.1
+  uiServer: docker.io/weaveworks/weave-gitops-enterprise-ui-server:v0.38.1
+.
+.
+.
+.
+.
+.
+```
+
+After that, This values file will be converted to `map[string]interface{}` then update the specific values from installation like `oidc` values.
+
+**Pros**
+
+- Values will always be up to date
+
+**Cons**
+
+- Lost the structured values files
+- Extra overhead for downloading / uncompressing the chart file
+
+
+
+#### option B) Refactoring the `install wge` step to the shape of [terraform](https://github.com/weaveworks/weave-gitops-enterprise/blob/7a26044174a046fbf25e7f005b895f8a0a5400dc/pkg/bootstrap/steps/terraform.go)
+
+where we dont manage values.  Something like consuming a helmrelease manifest as stated [here](https://docs.gitops.weave.works/docs/enterprise/getting-started/install-enterprise/#configure-helm-chart-and-commit).
+To generate and publish that manifest could be done as part of the release process (we have to do it as part of https://github.com/weaveworks/weave-gitops-enterprise/issues/2213) 
+
+#### option C) How flux does it where flux v2.1.0 can only bootstrap flux for v2.1.0
+
+so in this case refactoring install wge to just install the version that the cli belongs to. for example gitops-ee v0.38 only install v0.38, etc ... 
+see artifacts in https://github.com/fluxcd/flux2/releases/tag/v2.2.0 and https://github.com/fluxcd/flux2/blob/00c6ac81b9938e80a79c5b625b06cfb4f220c3db/pkg/manifestgen/install/manifests.go#L37
+
+
+
+