There is no problem preparing 0 value transfer which bundle only has one transaction. However, if we send a value transfer, the bundle would be inconsistent since all transactions' trunk/branch transactions are point to same tips.

Expected behavior:

Actual behavior:

Reproduction:

171.34.168.69 - - [22/Jun/2018 12:28:14] "GET http://www.minghui.org/ HTTP/1.1" 200 -
----------------------------------------
Exception happened during processing of request from ('171.34.168.69', 58976)
Traceback (most recent call last):
  File "/usr/lib/python2.7/SocketServer.py", line 290, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/usr/lib/python2.7/SocketServer.py", line 318, in process_request
    self.finish_request(request, client_address)
  File "/usr/lib/python2.7/SocketServer.py", line 331, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/usr/lib/python2.7/SocketServer.py", line 654, in __init__
    self.finish()
  File "/usr/lib/python2.7/SocketServer.py", line 713, in finish
    self.wfile.close()
  File "/usr/lib/python2.7/socket.py", line 283, in close
    self.flush()
  File "/usr/lib/python2.7/socket.py", line 307, in flush
    self._sock.sendall(view[write_offset:write_offset+buffer_size])
error: [Errno 32] Broken pipe
----------------------------------------

When sending the new claim request to swarm node, it will get the empty reply from server.

To reproduce this error, launch the server and use the following command.

curl http://localhost:8000 \
          -X POST \
          -H 'Content-Type: application/json' \
          -d '{"command":"new_claim","uuid": "SD9BCRDGJYWDHPTDNOPRULFWWG","part_a":"9JVXCXMFAMKLUQQCDACSWJVDLH","part_b":"9JVXCXMFAMKLUQQCDACSWJVDLH","exp_date":"20190101","claim_pic":"https://www.chill.ie/images/Customer-Care/ncb-example.png", "msg":"testing message"}'
curl: (52) Empty reply from server

The server-side will print the following error message.

Exception happened during processing of request from ('1.34.47.14', 54055)
Traceback (most recent call last):
  File "/usr/local/lib/python3.5/socketserver.py", line 313, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/usr/local/lib/python3.5/socketserver.py", line 341, in process_request
    self.finish_request(request, client_address)
  File "/usr/local/lib/python3.5/socketserver.py", line 354, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/usr/local/lib/python3.5/socketserver.py", line 681, in __init__
    self.handle()
  File "/usr/local/lib/python3.5/http/server.py", line 422, in handle
    self.handle_one_request()
  File "/usr/local/lib/python3.5/http/server.py", line 410, in handle_one_request
    method()
  File "server.py", line 63, in do_POST
    result = extension_tangleid.load(request_data)
  File "/home/ender503/iota-swarm-node/extensions/tangleid/main.py", line 13, in load
    bundle_hash = new_claim(data)
  File "/home/ender503/iota-swarm-node/extensions/tangleid/main.py", line 52, in new_claim
    response = send_transfer(tag, json.dumps(data), address, 0, dict_tips, debug=0)
  File "/home/ender503/iota-swarm-node/swarm_node.py", line 172, in send_transfer
    return str(obj_txn['hashes'][0])
IndexError: list index out of range

According to IOTA R&D roadmap, IOTA Foundation is planning to rewrite the Masked Authenticated Message (MAM) implementation. Once iota.lib.py completes the transition, dev-team will work on adding that functionality to PyOTA. Therefore the MAM temporarily workaround of python is implement it with iota.lib.js and running as an independent daemon that can access via REST API by swarm-node.

I create a new claim by new_claim command, but the transaction message is not JSON format on the
Tangle Explorer

Expected Format

{
  "uuid": "SD9BCRDGJYWDHPTDNOPRULFWWG",
  "part_a": "9JVXCXMFAMKLUQQCDACSWJVDLH",
  "part_b": "9JVXCXMFAMKLUQQCDACSWJVDLH",
  "command": "new_claim",
  "msg": "testing message",
  "exp_date": "20190101",
  "claim_pic": "https://www.chill.ie/images/Customer-Care/ncb-example.png"
}

Current Format

{u'uuid': u'SD9BCRDGJYWDHPTDNOPRULFWWG', u'part_a': u'9JVXCXMFAMKLUQQCDACSWJVDLH', u'part_b': u'9JVXCXMFAMKLUQQCDACSWJVDLH', u'command': u'new_claim', u'msg': u'testing message', u'exp_date': u'20190101', u'claim_pic': u'https://www.chill.ie/images/Customer-Care/ncb-example.png'}

Key index is address index from seed, but it is set as 1 currently:

Usually get_inputs() would return parameters that inputs need, so it should look like this:

addy.key_index = dict_inputs['inputs'][index_input].key_index

Unlike devnet, transaction without attachment_timestamp won't be confirm on mainnet even with recent hercules tip-sel algo. I can provide more results if needed. As for now, here's side by side comparison:

• Mainnet: With timestamp / Without timestamp
• Devnet: With timestamp / Without timestamp

The possible steps to implement load balancing with swarm nodes can be enumerated as follows:

1. Both public and private IP swarm node support because the swarm node may deploy on IoT devices that have private IP only.
2. First available process in the queue list has the highest priority because of swarm node deploy on a wide variety of devices, we should set the higher level device on the top.
3. No head-of-line blocking problem.

Reference:

• Request load balancing (passenger)

Since the extension only gets the parsed POST data from the server.py, it would be nice to let extension get the raw data, HTTP Header and request_path, it will give the extension more ability. 🤔

Since dcurl prefers Python 3 for packaging, it would be more consistent if we can switch iota-swarm-node to Python 3+ (version 3.7 in particular).