Merge pull request #324 from softwarepub/feature/adr-for-plugin-init

adr for plugin init descision

Author: nheeb

docs/adr/0013-plugin-init.md

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+<!--
+SPDX-FileCopyrightText: 2022 German Aerospace Center (DLR), Forschungszentrum Jülich, Helmholtz-Zentrum Dresden-Rossendorf
+
+SPDX-License-Identifier: CC-BY-SA-4.0
+-->
+# Installing plugins from the marketplace using hermes init
+
+* Status: accepted
+* Deciders: nheeb
+* Date: 2025-03-04
+
+## Context and Problem Statement
+
+For a smooth user experience common plugins (those which are on the marketplace) should be installable via `hermes init`. That however means we need to decide on a way for the plugins to ask question during that same init process.
+
+## Considered Options
+
+* **Full install**: Plugins are installed locally during `hermes init`, can hook into the init process, and ask questions themselves to adjust the `hermes.toml` or similar.
+* **No install**: Plugins are only added to the CI pipeline as `pip install ...` lines. Additional questions for the init process could be added in the marketplace input mask along with a property name under which the answer is stored in the `hermes.toml`.
+* **Partial install**: Plugins are only added to the CI pipeline as `pip install ...` lines. Additional questions for the init process are handled in a "detached" script that is downloaded, executed locally, and then deleted again (this script may only have dependencies of Hermes).
+
+## Decision Outcome
+
+Chosen option: "**Partial install**", because it is a good trade-off between giving plugins more controll over their init process and not being too invasive with local installs.
+
+## Pros and Cons of the Options
+
+### Full install
+- (+) Plugins have a lot of control over how they design their own init process.
+- (+) The plugin can be used locally on the device directly if the user intends to do so.
+- (-) The plugin might be installed unnecessarily, as locally only the init part may be executed.
+- (-) The plugin may introduce many dependencies that the user doesn’t necessarily need.
+- (-) There could be environment complications (e.g., if Hermes was installed with `pipx`).
+
+### No install
+- (+) Nothing is installed locally via `hermes init`.
+- (+) Overall, slightly less effort for the init command and plugin developers.
+- (-) The marketplace would need input masks for an arbitrary number of such questions.
+- (-) Plugins have little control over how they design their own init process.
+- (-) Plugins intended for local use must be installed manually.
+
+### Partial install
+- (+) Nothing is installed locally via `hermes init`.
+- (+) Plugins have relatively high control over how they design their own init process.
+- (-) Plugins intended for local use must be installed manually.