Tangle-Accelerator Development

tags: tangle-accelerator

HTTP Server

• build with C++ boost/beast library
• TODO: 測試多個 request 同時進來

JSON parser

解析 request，並以 JSON 格式 response，使用 cJSON 實做

下列 function 需要 serialization:

• generate_address
• get_tips
• send_transfer

Function Overview

core function 皆會使用到 entangled/cclient，參考到 IOTA cclient 使用指南

Core

• ta_generate_address - may need updated(下方 issue)
• ta_get_tips - may need updated
  • cclient_get_txn_to_approve - may need updated
  • cclient_get_tips - may need updated
• ta_send_transfer - on-going
• ta_find_transaction_by_tag - on-going
• ta_get_txn_msg

Should be deprecated

• insert_to_trytes: cclient 已有其他方式
• ta_attach_debug_message_to_tangle: 交給 test case 處理

TangleID

• TODO

send_transfer

dcurl

為了使用 dcurl 進行 PoW 加速，我們需要
實做 attachToTangle 流程

send_transfer Flow

• Generate new address
• Make transaction
  • Set address
  • Set tag
  • Set message
  • Set value
• Make bundle
  • Add transaction
  • Finalize
    • calculate bundle hash
    • Fill bundle hash through txs
      • pyota will fill in bundle hash in finalize
• getTransactionToApprove
• get transaction trytes
  • transaction_sesrialize_to_flex_trits
• Fill in trunk, branch in each transaction
• Fill in timestamp in each transaction
• PoW
• fill in nonce

IOTA transaction tryte offset

Transaction raw trytes

transaction_sesrialize_to_flex_trits

  def as_tryte_string(self):
    # type: () -> TransactionTrytes
    """ 
    Returns a TryteString representation of the transaction.
    """
    return TransactionTrytes(
       self.signature_message_fragment
     + self.address.address
     + self.value_as_trytes
     + self.legacy_tag
     + self.timestamp_as_trytes
     + self.current_index_as_trytes
     + self.last_index_as_trytes
     + self.bundle_hash
     + self.trunk_transaction_hash                                                                                                                           
     + self.branch_transaction_hash
     + self.tag
     + self.attachment_timestamp_as_trytes
     + self.attachment_timestamp_lower_bound_as_trytes
     + self.attachment_timestamp_upper_bound_as_trytes
     + self.nonce
    )   

common/model: Transfer

Transfer

typedef struct _transfer {
  transfer_type_e type;
  const flex_trit_t *address;
  const flex_trit_t *tag;
  int64_t value;
  uint64_t timestamp;
  void *meta;  // extend informations depended on transfer type.
} transfer_t;

3 types of transfer, each one has its own meta data structure:

DATA

typedef struct _transfer_data {
  const flex_trit_t *data;
  size_t len;
} transfer_data_t;

VALUE_OUT

typedef struct _transfer_value_out {
  const flex_trit_t *seed;
  uint8_t security;
  uint64_t seed_index;
} transfer_value_out_t;

VALUE_IN

typedef struct _transfer_value_in {
  // can have up to 2187 trytes as data
  size_t len;
  const flex_trit_t *data;
} transfer_value_in_t;

Transfer Iterator
transfer_iterator_new

• In this function, bundle_hash is calculated

transfer_iterator_next

• generate transaction from transfer array

unkown nouns

• remainder in prepare_transfers

Send_transfer

1. prepare_transfer
2. get bundle trits
3. send_trytes

Prepare_transfer

1. transfer_iterator_new
   • cacluate bundle hash
2. transfer_interator_next
   • generate a transaction_t object
   • fill in bundle, address, tag, obsolete_tag, timestamp, current_index, last_index
   • fill in metadata
     • DATA: message
     • VALUE_OUT: value, signature
       • if index == 0, gen signature
     • VALUE_IN: value, signature
3. bundle_add_transaction
4. bundle_finalize
   • Since bundle hash is calculated in transfer_iterator_new, why do we still need bundle_finalize?
   • source code link

Send_trytes

1. get_transactions_to_approve
2. attach_to_tangle
3. sotre_and_broadcast

cache server 不能獨立於 tangle-accelerator 的原因

• 安全考量，使用者也需要信任 Caching server，但 TA 是安全的 (Root Of Trust)
• 如果 tx invalid, caching server 也不知道，TA 還能直接向 full node 查證