Create SC for Decentralized lists

[damip]

A simple decentralized list tool

A simple decentralized tool to make lists.

Smart contract

Datastore layout

In the datastore we simply have one entry per entry of the list list_name:

["dlist"][len(list_name)][list_name][key] -> [value]  // note that len(list_name) is a constant-size integer that prevents key collisions when we have list names of various lengths

Smart contract interface:

read_item(list: Vec<u8>, key: Vec<u8>) -> Vec<u8>
    reads the value of an item, fails if does not exist

item_exists(list: Vec<u8>, key: Vec<u8>) -> bool
    checks if an item exists

remove_item(list: Vec<u8>, key: Vec<u8>)
    owner only
    removes an item, fails if does not exist

insert_item(list: Vec<u8>, key: Vec<u8>, value: Vec<u8>)
    owner only
    overwrites if exists

Web interface

A simple two-step interface:

• step 1: the list name is taken from a URL parameter https://zzzzzzzzz.zzzzz/yyy/?list=xxxxx and displayed in the frontend. The user is asked to enter a key
  • if key exists in the datastore at ["dlist"][len(list_name)][list_name][key] (do not use the item_exists function, directly read the datastore):
    • step 2:
      • Display that the key is in the list
      • Show the associated value in a multiline textarea and allow the user to update it
      • Display a Remove from list button to remove the item
  • if the key is not in the list
    • step 2:
      • Display the key.
      • Allow the user to enter a value in a multiline textarea. Max len = 10 megabytes when encoded to utf8
      • Have a "Insert to list" button to insert the new value in the list

[pivilartisant]

@damip i believe there is a need to add a feature here that will allow users to remove an indexed item.

Use case would be: I (the users) have an indexed website, after deleting this indexed website I do not want it indexed in this list any more (we retrieve the indexed website in the uploader front end for example)

Wdyt ? does the current implementation satisfy this need ?

[damip]

@damip i believe there is a need to add a feature here that will allow users to remove an indexed item.

Use case would be: I (the users) have an indexed website, after deleting this indexed website I do not want it indexed in this list any more (we retrieve the indexed website in the uploader front end for example)

Wdyt ? does the current implementation satisfy this need ?

In this spec, only the owner of that list can add or remove (see spec) so this question does not apply

[damip]

This proposal is about a generic "list" contract that allows its owner to keep a curated list of arbitrary stuff. It could be useful for example to have curated lists of deweb providers, proposed website blacklists and so on...

For actual decentralized website listing/indexing, instead we are using: https://github.com/massalabs/DeWeb/tree/main/deweb-index which automatically indexes sites based on a call to the "update" function. If we allow users to completely delete a website (delete all the datastore entries including the DEWEB_VERSION of the website), a simple call to the update() function of that indexer will remove the website from the index.

Note that the deweb index is meant to evolve into a fully features website listing and search engine according to https://forum.massa.community/t/decentralized-search-engine-for-the-decentralized-web/