Wire newly introduce governance commands in the CLI

  Mostly plumbing and parser implementation following what already exists.

cardano-cli/ChangeLog.md

@@ -4,6 +4,23 @@
 
 - Remove cardano-cli address build-script ([PR 4700](https://github.com/input-output-hk/cardano-node/pull/4700))
 
+- New commands for on-chain SPOs polls under `shelley governance`:
+  - `create-poll`:
+      For the current governing entities, as a means to create new polls.
+
+  - `answer-poll`:
+      For participants who want to answer a given poll.
+
+  - `verify-poll`:
+      For anyone who seek to verify a poll entry (e.g. explorers)
+
+  The commands are built to fit and play nicely within the cardano-cli.
+  The poll and answers structures are based on transaction metadata and
+  require to be embedded in an actual transaction. The added commands
+  however only works from metadata and raw "GovernancePoll" envelopes.
+
+  See [CIP proposal](https://github.com/cardano-foundation/CIPs/pull/496) for details.
+
 ### Features
 
 - Default to the ledger's CDDL format for transaction body creation by removing flags `--cddl-format` and `--cli-format` from `build` and `build-raw` ([PR 4303](https://github.com/input-output-hk/cardano-node/pull/4303))

cardano-cli/src/Cardano/CLI/Shelley/Commands.hs

@@ -416,6 +416,18 @@ data GovernanceCmd
                              [VerificationKeyFile]
                              ProtocolParametersUpdate
                              (Maybe FilePath)
+  | GovernanceCreatePoll
+      Text -- Prompt
+      [Text] -- Choices
+      (Maybe Word) -- Nonce
+      OutputFile
+  | GovernanceAnswerPoll
+      FilePath -- Poll file
+      SigningKeyFile
+      (Maybe Word) -- Answer index
+  | GovernanceVerifyPoll
+      FilePath -- Poll file
+      FilePath -- Metadata JSON file
   deriving Show
 
 renderGovernanceCmd :: GovernanceCmd -> Text
@@ -426,6 +438,9 @@ renderGovernanceCmd cmd =
     GovernanceMIRTransfer _ _ TransferToTreasury -> "governance create-mir-certificate transfer-to-treasury"
     GovernanceMIRTransfer _ _ TransferToReserves -> "governance create-mir-certificate transfer-to-reserves"
     GovernanceUpdateProposal {} -> "governance create-update-proposal"
+    GovernanceCreatePoll{} -> "governance create-poll"
+    GovernanceAnswerPoll{} -> "governance answer-poll"
+    GovernanceVerifyPoll{} -> "governance verify-poll"
 
 data TextViewCmd
   = TextViewInfo !FilePath (Maybe OutputFile)

cardano-cli/src/Cardano/CLI/Shelley/Parsers.hs

@@ -1090,6 +1090,15 @@ pGovernanceCmd =
     , subParser "create-update-proposal"
       $ Opt.info pUpdateProposal
       $ Opt.progDesc "Create an update proposal"
+    , subParser "create-poll"
+      $ Opt.info pGovernanceCreatePoll
+      $ Opt.progDesc "Create an SPO poll"
+    , subParser "answer-poll"
+      $ Opt.info pGovernanceAnswerPoll
+      $ Opt.progDesc "Answer an SPO poll"
+    , subParser "verify-poll"
+      $ Opt.info pGovernanceVerifyPoll
+      $ Opt.progDesc "Verify an answer to a given SPO poll"
     ]
   where
     mirCertParsers :: Parser GovernanceCmd
@@ -1151,6 +1160,78 @@ pGovernanceCmd =
                         <*> pProtocolParametersUpdate
                         <*> optional pCostModels
 
+    pGovernanceCreatePoll :: Parser GovernanceCmd
+    pGovernanceCreatePoll =
+      GovernanceCreatePoll
+        <$> pPollQuestion
+        <*> some pPollAnswer
+        <*> optional pPollNonce
+        <*> pOutputFile
+
+    pGovernanceAnswerPoll :: Parser GovernanceCmd
+    pGovernanceAnswerPoll =
+      GovernanceAnswerPoll
+        <$> pPollFile
+        <*> pSigningKeyFile Input
+        <*> optional pPollAnswerIndex
+
+    pGovernanceVerifyPoll :: Parser GovernanceCmd
+    pGovernanceVerifyPoll =
+      GovernanceVerifyPoll
+        <$> pPollFile
+        <*> pPollMetadataFile
+
+
+pPollQuestion :: Parser Text
+pPollQuestion =
+  Opt.strOption
+    (  Opt.long "question"
+    <> Opt.metavar "STRING"
+    <> Opt.help "The question for the poll."
+    )
+
+pPollAnswer :: Parser Text
+pPollAnswer =
+  Opt.strOption
+    (  Opt.long "answer"
+    <> Opt.metavar "STRING"
+    <> Opt.help "A possible choice for the poll. The option is repeatable."
+    )
+
+pPollAnswerIndex :: Parser Word
+pPollAnswerIndex =
+  Opt.option auto
+    (  Opt.long "answer"
+    <> Opt.metavar "INT"
+    <> Opt.help "The index of the chosen answer in the poll. Optional. Asked interactively if omitted."
+    )
+
+pPollFile :: Parser FilePath
+pPollFile =
+  Opt.strOption
+    (  Opt.long "poll-file"
+    <> Opt.metavar "FILE"
+    <> Opt.help "Filepath to the ongoing poll."
+    <> Opt.completer (Opt.bashCompleter "file")
+    )
+
+pPollNonce :: Parser Word
+pPollNonce =
+  Opt.option auto
+    (  Opt.long "nonce"
+    <> Opt.metavar "UINT"
+    <> Opt.help "An (optional) nonce for non-replayability."
+    )
+
+pPollMetadataFile :: Parser FilePath
+pPollMetadataFile =
+  Opt.strOption
+    (  Opt.long "metadata-file"
+    <> Opt.metavar "FILE"
+    <> Opt.help "Filepath of the metadata file, in (detailed) JSON format."
+    <> Opt.completer (Opt.bashCompleter "file")
+    )
+
 pTransferAmt :: Parser Lovelace
 pTransferAmt =
     Opt.option (readerFromParsecParser parseLovelace)

cardano-cli/src/Cardano/CLI/Shelley/Run/Governance.hs

@@ -112,6 +112,12 @@ runGovernanceCmd (GovernanceGenesisKeyDelegationCertificate genVk genDelegVk vrf
   runGovernanceGenesisKeyDelegationCertificate genVk genDelegVk vrfVk out
 runGovernanceCmd (GovernanceUpdateProposal out eNo genVKeys ppUp mCostModelFp) =
   runGovernanceUpdateProposal out eNo genVKeys ppUp mCostModelFp
+runGovernanceCmd (GovernanceCreatePoll prompt choices nonce out) =
+  runGovernanceCreatePoll prompt choices nonce out
+runGovernanceCmd (GovernanceAnswerPoll poll sk ix) =
+  runGovernanceAnswerPoll poll sk ix
+runGovernanceCmd (GovernanceVerifyPoll poll metadata) =
+  runGovernanceVerifyPoll poll metadata
 
 runGovernanceMIRCertificatePayStakeAddrs
   :: Shelley.MIRPot