Merge bitcoin/bitcoin#22918: rpc: Add level 3 verbosity to getblock RPC call (#21245 modified)

5c34507ecb core_write: Rename calculate_fee to have_undo for clarity (fyquah)
8edf6204a8 release-notes: Add release note about getblock verbosity level 3. (fyquah)
459104b2aa rest: Add test for prevout fields in getblock (fyquah)
4330af6f72 rpc: Add test for level 3 verbosity getblock rpc call. (fyquah)
51dbc167e9 rpc: Add level 3 verbosity to getblock RPC call. (fyquah)
3cc95345ca rpc: Replace boolean argument for tx details with enum class. (fyquah)

Pull request description:

  Author of #21245 expressed [time issues](https://github.com/bitcoin/bitcoin/pull/21245#issuecomment-902332088) in the original PR. Given that #21245 has received a lot of review*, I have decided to open this new pull request with [modifications required to get ACK from luke-jr ](https://github.com/bitcoin/bitcoin/pull/21245#issuecomment-905150806) and a few nits of mine.

  ### Original PR description

  > Display the prevout in transaction inputs when calling getblock level 3 verbosity. This PR affects the existing `/rest/block` API by adding a `prevout` fields to tx inputs. This is mentioned in the change to the release notes.
  >
  > I added some functional tests that
  >
  >     * checks that the RPC call still works when TxUndo can't be found
  >
  >     * Doesn't display the "value" or "scriptPubKey" of the previous output when at a lower verbosity level
  >
  >
  > This "completes" the issue #18771

  ### Possible improvements

  * b0bf4f255f - I can include even this commit to this PR if deemed useful or I can leave it for a follow-up PR. See https://github.com/bitcoin/bitcoin/pull/21245#issuecomment-894853784 for more context.

  ### Examples

  Examples of the `getblock` output with various verbose levels. Note that `000000000000001f682b188971cc1a121546be4e9d5baf22934fdc7f538288d5` contains only 2 transactions.

  #### Verbose level 0

  ```bash
  ./bitcoin-cli -testnet getblock 000000000000001f682b188971cc1a121546be4e9d5baf22934fdc7f538288d5 0
  ```

  ##### Verbose level 1

  ```bash
  ./bitcoin-cli -testnet getblock 000000000000001f682b188971cc1a121546be4e9d5baf22934fdc7f538288d5 1
  ```

  ##### Verbose level 2

  ```bash
  ./bitcoin-cli -testnet getblock 000000000000001f682b188971cc1a121546be4e9d5baf22934fdc7f538288d5 2
  ```

  ##### Verbose level 3

  ```bash
  ./bitcoin-cli -testnet getblock 000000000000001f682b188971cc1a121546be4e9d5baf22934fdc7f538288d5 3
  ```

  #### REST

  ```bash
  curl -H "content-type:text/plain;" http://127.0.0.1:18332/rest/block/000000000000001f682b188971cc1a121546be4e9d5baf22934fdc7f538288d5.json
  ```

  <sub>* ... and my everyday obsessive checking of my email inbox whether the PR moves forward.</sub>

  Edit laanwj: Removed at symbol from message, and large example output to prevent it from all ending up in the commit message.

ACKs for top commit:
  0xB10C:
    ACK 5c34507ecb
  meshcollider:
    utACK 5c34507ecb
  theStack:
    ACK 5c34507ecb 👘
  promag:
    Concept ACK 5c34507ecb

Tree-SHA512: bbff120d8fd76e617b723b102b0c606e0d8eb27f21c631d5f4cdab0892137c4bc7c65b1df144993405f942c91be47a26e80480102af55bff22621c19f518aea3

test/functional/interface_rest.py

@@ -318,6 +318,15 @@ class RESTTest (BitcoinTestFramework):
                             if 'coinbase' not in tx['vin'][0]}
         assert_equal(non_coinbase_txs, set(txs))
 
+        # Verify that the non-coinbase tx has "prevout" key set
+        for tx_obj in json_obj["tx"]:
+            for vin in tx_obj["vin"]:
+                if "coinbase" not in vin:
+                    assert "prevout" in vin
+                    assert_equal(vin["prevout"]["generated"], False)
+                else:
+                    assert "prevout" not in vin
+
         # Check the same but without tx details
         json_obj = self.test_rest_request(f"/block/notxdetails/{newblockhash[0]}")
         for tx in txs:

test/functional/rpc_blockchain.py

@@ -434,17 +434,55 @@ class BlockchainTest(BitcoinTestFramework):
         miniwallet.send_self_transfer(fee_rate=fee_per_kb, from_node=node)
         blockhash = self.generate(node, 1)[0]
 
-        self.log.info("Test getblock with verbosity 1 doesn't include fee")
-        block = node.getblock(blockhash, 1)
-        assert 'fee' not in block['tx'][1]
+        def assert_fee_not_in_block(verbosity):
+            block = node.getblock(blockhash, verbosity)
+            assert 'fee' not in block['tx'][1]
 
-        self.log.info('Test getblock with verbosity 2 includes expected fee')
-        block = node.getblock(blockhash, 2)
-        tx = block['tx'][1]
-        assert 'fee' in tx
-        assert_equal(tx['fee'], tx['vsize'] * fee_per_byte)
+        def assert_fee_in_block(verbosity):
+            block = node.getblock(blockhash, verbosity)
+            tx = block['tx'][1]
+            assert 'fee' in tx
+            assert_equal(tx['fee'], tx['vsize'] * fee_per_byte)
 
-        self.log.info("Test getblock with verbosity 2 still works with pruned Undo data")
+        def assert_vin_contains_prevout(verbosity):
+            block = node.getblock(blockhash, verbosity)
+            tx = block["tx"][1]
+            total_vin = Decimal("0.00000000")
+            total_vout = Decimal("0.00000000")
+            for vin in tx["vin"]:
+                assert "prevout" in vin
+                assert_equal(set(vin["prevout"].keys()), set(("value", "height", "generated", "scriptPubKey")))
+                assert_equal(vin["prevout"]["generated"], True)
+                total_vin += vin["prevout"]["value"]
+            for vout in tx["vout"]:
+                total_vout += vout["value"]
+            assert_equal(total_vin, total_vout + tx["fee"])
+
+        def assert_vin_does_not_contain_prevout(verbosity):
+            block = node.getblock(blockhash, verbosity)
+            tx = block["tx"][1]
+            if isinstance(tx, str):
+                # In verbosity level 1, only the transaction hashes are written
+                pass
+            else:
+                for vin in tx["vin"]:
+                    assert "prevout" not in vin
+
+        self.log.info("Test that getblock with verbosity 1 doesn't include fee")
+        assert_fee_not_in_block(1)
+
+        self.log.info('Test that getblock with verbosity 2 and 3 includes expected fee')
+        assert_fee_in_block(2)
+        assert_fee_in_block(3)
+
+        self.log.info("Test that getblock with verbosity 1 and 2 does not include prevout")
+        assert_vin_does_not_contain_prevout(1)
+        assert_vin_does_not_contain_prevout(2)
+
+        self.log.info("Test that getblock with verbosity 3 includes prevout")
+        assert_vin_contains_prevout(3)
+
+        self.log.info("Test that getblock with verbosity 2 and 3 still works with pruned Undo data")
         datadir = get_datadir_path(self.options.tmpdir, 0)
 
         self.log.info("Test getblock with invalid verbosity type returns proper error message")
@@ -458,8 +496,10 @@ class BlockchainTest(BitcoinTestFramework):
         # Move instead of deleting so we can restore chain state afterwards
         move_block_file('rev00000.dat', 'rev_wrong')
 
-        block = node.getblock(blockhash, 2)
-        assert 'fee' not in block['tx'][1]
+        assert_fee_not_in_block(2)
+        assert_fee_not_in_block(3)
+        assert_vin_does_not_contain_prevout(2)
+        assert_vin_does_not_contain_prevout(3)
 
         # Restore chain state
         move_block_file('rev_wrong', 'rev00000.dat')