doc: Add idea for composable functions

README.md

@@ -15,6 +15,7 @@ Task sources:
 * :heavy_check_mark: __Trello__
 * :x: Nextcloud Deck (not yet) - [API Reference](https://github.com/nextcloud/deck/blob/master/docs/API.md)
 * :x: Wekan (not yet) - [API Reference](https://github.com/wekan/wekan/wiki/REST-API)
+* :x: Gitea / Forgejo (not yet)
 * :x: Libreboard (not yet)
 * :x: Github Projects (not yet)
 
@@ -24,9 +25,18 @@ Source selection
 * :heavy_check_mark: __Favorited boards__
 * :heavy_check_mark: __Only selected ones__
 
+Actions
+
+* :heavy_check_mark: __List tasks__
+* :x: Create task
+* :x: Read task
+* :x: Update task
+* :x: Remove task
+
 Delivery via:
 
 * :heavy_check_mark: __E-mail__
+* :x: Terminal
 * :x: Telegram
 * :x: Slack
 * :x: SMS

doc/draft-composable-functions.md

@@ -0,0 +1,51 @@
+# Composable functions
+
+## Example
+
+### With pipes
+
+    musala-pull SOURCE \
+      | musala-add TASK \
+      | musala-remove --purge SOMETASK \
+      | musala-push DEST
+
+### With internal filters
+
+Also writeable like
+
+    musala pull SOURCE % add TASK1 % remove --purge TASK2 % push DEST
+
+
+## Commands
+
+### musala pull
+
+Download all tasks from source
+
+Get tasks from remote source
+
+Writes tasks as JSON to stdout
+
+### musala add
+
+Add new task
+
+Get tasks from stdin (json)
+
+Add a new task
+
+Writes tasks as JSON to stdout
+
+### musala remove
+
+* Get tasks from stdin (json)
+* Mark a task as removed
+* Remove tasks marked as remove (if --purge enabled)
+* Writes tasks as JSON to stdout
+
+### musala push
+
+* Get tasks from stdin (json)
+* Writes tasks to REMOTE DESTINATION
+
+