Proposing a Transaction

Proposed transactions can be used everywhere multiple parties have to agree for a transaction to become valid.

Crafting a Transaction

It is recommended that the reader first reads through the following tutorial:

Proposing a Transaction

A proposed transaction is encapsulated within another operation type. We can achieve this by slightly modifying our procedure:

>>> begin_builder_transaction
>>> add_operation_to_builder_transaction $HANDLE [opId, {operation}]

# New:
>>> propose_builder_transaction2 $HANDLE <proposing-account-name> <expiration> <review-period-secs> false

>>> set_fees_on_builder_transaction $HANDLE BTS
>>> sign_builder_transaction $HANDLE true

Definition

signed_transaction graphene::wallet::wallet_api::propose_builder_transaction(transaction_handle_type handle, time_point_sec expiration = time_point::now() + fc::minutes(1), uint32_t review_period_seconds = 0, bool broadcast = true)
signed_transaction graphene::wallet::wallet_api::propose_builder_transaction2(transaction_handle_type handle, string account_name_or_id, time_point_sec expiration = time_point::now() + fc::minutes(1), uint32_t review_period_seconds = 0, bool broadcast = true)

Approving a Proposal

A proposal can be approved simply by:

approve_proposal <proposing-account> <proposal_id> {"active_approvals_to_add" : ["<account-name-required-for-approval>"]} false

When replacing the final false with true, the transaction will be broadcasted!

Available approval options are:

  • active_approvals_to_add
  • active_approvals_to_remove
  • owner_approvals_to_add
  • owner_approvals_to_remove
  • key_approvals_to_add
  • key_approvals_to_remove

Definition

signed_transaction graphene::wallet::wallet_api::approve_proposal(const string &fee_paying_account, const string &proposal_id, const approval_delta &delta, bool broadcast)

Approve or disapprove a proposal.

Return
the signed version of the transaction
Parameters
  • fee_paying_account: The account paying the fee for the op.
  • proposal_id: The proposal to modify.
  • delta: Members contain approvals to create or remove. In JSON you can leave empty members undefined.
  • broadcast: true if you wish to broadcast the transaction

Example: Setting Smartcoin parameter

A simple asset_update takes the following form:

get_prototype_operation asset_update_bitasset_operation
[
  12,{
    "fee": {
      "amount": 0,
      "asset_id": "1.3.0"
    },
    "issuer": "1.2.0",
    "asset_to_update": "1.3.0",
    "new_options": {
      "feed_lifetime_sec": 86400,
      "minimum_feeds": 1,
      "force_settlement_delay_sec": 86400,
      "force_settlement_offset_percent": 0,
      "maximum_force_settlement_volume": 2000,
      "short_backing_asset": "1.3.0",
      "extensions": []
    },
    "extensions": []
  }
]

The operation id for the asset_update_bitasset_operation is thus 12 (third line) and the core elements (removing fee) of this operation take the form:

{
   "issuer": "1.2.0",
   "asset_to_update": "1.3.0",
   "new_options": {
     "feed_lifetime_sec": 86400,
     "minimum_feeds": 1,
     "force_settlement_delay_sec": 86400,
     "force_settlement_offset_percent": 0,
     "maximum_force_settlement_volume": 2000,
     "short_backing_asset": "1.3.0",
     "extensions": []
   },
   "extensions": []
}

We add an operation to a transaction as follows (line breaks inserted for readability):

>>> begin_builder_transaction
0
>>> add_operation_to_builder_transaction
        0
        [12, {
              "asset_to_update": "1.3.113",
              "issuer": "1.2.0",
              "extensions": [],
              "new_options": {
                "feed_lifetime_sec": 86400,
                "force_settlement_delay_sec": 86400,
                "short_backing_asset": "1.3.0",
                "maximum_force_settlement_volume": 200,
                "force_settlement_offset_percent": 0,
                "minimum_feeds": 7,
                "extensions": []
              },
            }]

The corresponding asset id can be obtained with get_asset.

Now let’s make it a proposal for the committee members to sign:

>>> propose_builder_transaction2 0 init0 "2015-12-10T14:55:00" 3600 false

We add a fee payed in BTS, sign and broadcast the transaction (if valid):

>>> set_fees_on_builder_transaction 0 BTS
>>> sign_builder_transaction 0 true