From 7e11c5cbf25eb93636ec3ded79656f63868f0ca5 Mon Sep 17 00:00:00 2001
From: Klaas Freitag <freitag@owncloud.com>
Date: Fri, 19 Mar 2021 14:17:43 +0100
Subject: [PATCH] Add draft of adr for spaces API.

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+# 5. Graph API for Spaces
+
+* Status: proposed
+* Deciders: @butonic, @micbar, @dragotin, @hodyroff, @pmaier1
+* Date: 2021-03-19
+
+Technical Story: API to enable the concept of [Spaces](https://github.com/owncloud/enterprise/issues/3863)
+
+## Context and Problem Statement
+
+As one of the building blocks for Spaces in oCIS we plan to add an API that returns information about available spaces.
+
+> Note: The term "spaces" is used here in the context of "a space where files can be saved", similar to a directory. It is not to be confused with space in the sense of file space for example.
+
+The purpose of this new API is to give clients a very simple way to query the dynamic list of spaces, that the user has access to. Clients can provide a way better user experience with that.
+
+This API would even allow to provide (WebDAV-) endpoints depending on the kind and version of the client asking for it.
+
+This ADR discusses how this API could be designed.
+
+## Decision Drivers
+
+- Make it easy to work with a dynamic list of spaces of a user for the clients.
+- No longer the need to make assumptions about WebDAV- and other routes in clients.
+- More meta data available about spaces for a better user experience.
+- Part of the bigger spaces plan.
+- Important to consider in client migration scenarios, ie. in CERN.
+
+## Considered Options
+
+1. [Microsoft Graph API](https://developer.microsoft.com/en-us/graph) inspired API that provides the requested information.
+
+## Decision Outcome
+
+This the DRAFT for the API.
+
+### API to Get Info about Spaces
+
+ownCloud servers provide an API to query for available spaces of an user.
+
+Most important, the API returns the WebDAV endpoint for each space. With that, clients do not have to make assumptions about WebDAV routes any more.
+
+See [Drive item in Microsoft Graph API](https://docs.microsoft.com/de-de/graph/api/resources/onedrive?view=graph-rest-1.0)
+
+### Get "Home folder"
+
+Retrieve information about the home space of a user. Note: This is only a subset of the spaces the user might have access to.
+
+API Call: `/me/drive`: Returns the information of the users home folder.
+
+### Get All Spaces of a User
+
+Retrieve a list of available spaces of a user. This includes all spaces the user has access to at that moment, also the home space.
+
+API Call: `/me/drives`: Returns a list of spaces.
+
+### Common Reply
+
+The reply to both calls is either one or a list of [Drive representation objects](https://docs.microsoft.com/de-de/graph/api/resources/drive?view=graph-rest-1.0):
+
+```
+{
+  "id": "string",
+  "createdDateTime": "string (timestamp)",
+  "description": "string",
+  "driveType": "personal | business | documentLibrary",
+  "eTag": "string",
+  "lastModifiedDateTime": "string (timestamp)",
+  "name": "string",
+  "owner": { "@odata.type": "microsoft.graph.identitySet" },
+  "webUrl": "url"
+}
+
+```
+
+The meaning of the object are in ownClouds context:
+
+1. **id** - a unique ID identifying the space
+2. **driveType** - describing the type of the space.
+3. **eTag** - the current ETag of the space
+4. **owner** - an owner object to whom the space belong
+5. **webUrl** - the relative Webdav path in ownCloud. It must include the `remote.php` part in oC10 installations.
+
+
+The following driveType values are available in the first step, but might be enhanced later:
+
+* **personal**: The users home space
+* **documentLibrary**: The project spaces available for the user
+* **shares**: The share jail, contains all shares for the user (*)
+
+The (*) marked types are not defined in the official MS API.
+
+### Positive Consequences
+
+- A well understood and mature API from Microsoft adopted to our needs.
+- Prerequisite for Spaces in oCIS.
+- Enables further steps in client development.
+
+### Negative Consequences
+
+- Migration impact on existing installations. Still to be investigated.
+
+### Open Topics
+
+- Do we need a new WebDAV endpoint?
+- What are the WebDAV pathes for Trashbin, Versions
+	+ option: additional entries in the reply struct