Implementation of a DApp (Decentralized Application) using decentralized keywords Search Engine based on a hypercube structure; integrated with IPFS and Algorand blockchain using Python.

Smart Contracts are developed with Reach language and are located inside SmartContract_UI.

The folder /SmartContract_UI/test-suite contains some smart contracts and the simulation scripts.

Working on proof of location, simulated in a permissionless system.

Working on interactions between Python and Smart Contract.

Performance evaluation with startSimulation.py .

• Docker
• Docker Compose -> install

git clone
cd hypfs/server
docker build -t hypercube .
cd ../client
docker build -t hypercube-client .
cd ..
docker-compose up -d

To run in "local mode" skip usage section and use:

• docker run -d --name ipfs_host -e IPFS_PROFILE=server -v $ipfs_staging:/export -v $ipfs_data:/data/ipfs -p 4001:4001 -p 4001:4001/udp -p 127.0.0.1:8080:8080 -p 127.0.0.1:5001:5001 ipfs/go-ipfs:latest: this allow to start an IPFS docker container Source
• Install both the requirements.txt inside client and server directories pip3 install -r requirements.txt
• Start the server: python server.py 8881, where 8881 is the port
• Start the client: python menu.py /ip4/127.0.0.1/tcp/5001 1

1. Check status docker-compose logs -f for all services docker-compose logs -f hypercube_0 for an hypercube node `docker-compose logs -f ipfs

2. Start client hash docker-compose run hypercube-client bash

3. Work with the client bash python menu.py /ip4/127.0.0.1/tcp/5001 1

   • the first parameter is your IPFS node API address
   • the second parameter is the ID one Hypercube node (are configured to be from 1 to 8)

   python

   • to open a python console, then:
   • from client import Client
   • client = Client('/ip4/127.0.0.1/tcp/5001',1) (a warning will appear)
   • client.add_obj('test.txt',3) for adding an object, use only keywords from 0 to 7
   • client.pin_search(3,-1) to search using the keyword '3'
   • client.get_obj('QmT78zSuBmuS4z925WZfrqQ1qHaJ56DQaTfyMUF7F8ff5o') will download an object from IPFS in the objects directory

• contains the hypercube and node implementation
• /hop_counter contains an app for counting network hops

• contains all the client for interacting with nodes
• /results: contains the results of tests carried out with the bench.py script.
• /demo: contains a library for the interface of the menu.py script.
• /objects: contains the objects downloaded from IPFS.

• menu.py: script that provides a user-friendly command line UI.
• bench.py: script used for testing.

• Zichichi M., Serena L., Ferretti S., D'Angelo G., Governing Decentralized Complex Queries Through a DAO, in Proc. of the Conference on Information Technology for Social Good (GoodIT). 9-11 September 2021
• Zichichi M., Serena L., Ferretti S., D'Angelo G., Towards Decentralized Complex Queries over Distributed Ledgers: a Data Marketplace Use-case , in Proc. of the 30th IEEE International Conference on Computer Communications and Networks (ICCCN). 3rd International Workshop on Social (Media) Sensing. 19-22 July 2021

Apache License 2.0

• writeobblockchain file: Remove the passphase
• writeobblockchain file: Send the transaction to a specific address: the address of the COMPANY
• SmartContract_UI/index.rsh: Notify the attacher when he is inserting a new position. If his DID already exists, the position will not be added to the map
• SmartContract_UI/index.mjs: Refactoring the amount sent by Verifier to smart contract
• SmartContract_UI: recover the address of users in the map passing a specific row of the map to frontend. Then split and passed the address to backend
• SmartContract_UI/index.rsh: add the timeout to the first API (insert_position)
• Display the whole map to the Verifier, when he required for that