conway governance hash: add option to write hash to file (--out-file)

cardano-cli/cardano-cli.cabal

@@ -317,6 +317,7 @@ test-suite cardano-cli-test
 
   other-modules:        Test.Cli.CliIntermediateFormat
                         Test.Cli.FilePermissions
+                        Test.Cli.Governance.Hash
                         Test.Cli.ITN
                         Test.Cli.JSON
                         Test.Cli.Pioneers.Exercise1

cardano-cli/src/Cardano/CLI/EraBased/Commands/Governance/Hash.hs

@@ -20,8 +20,9 @@ newtype GovernanceHashCmds era = GovernanceHashCmd (GovernanceHashCmdArgs era)
 
 data GovernanceHashCmdArgs era
   = GovernanceHashCmdArgs {
-      eon    :: !(ConwayEraOnwards era),
-      toHash :: !GovernanceHashSource
+      eon     :: !(ConwayEraOnwards era)
+    , toHash  :: !GovernanceHashSource
+    , moutFile :: !(Maybe (File () Out)) -- ^ The output file to which the hash is written
   } deriving Show
 
 data GovernanceHashSource

cardano-cli/src/Cardano/CLI/EraBased/Options/Governance/Hash.hs

@@ -25,9 +25,10 @@ pGovernanceHashCmds era = do
   return
     $ subParser "hash"
     $ Opt.info
-        ( Cmd.GovernanceHashCmd . GovernanceHashCmdArgs eon
-            <$> pGovernanceHashSource
-        )
+        ( fmap Cmd.GovernanceHashCmd
+            (GovernanceHashCmdArgs eon
+               <$> pGovernanceHashSource
+               <*> optional pOutputFile))
     $ Opt.progDesc "Compute the hash to pass to the various --*-hash arguments of governance commands."
 
 pGovernanceHashSource :: Parser Cmd.GovernanceHashSource

cardano-cli/src/Cardano/CLI/EraBased/Run/Governance/Hash.hs

@@ -24,12 +24,10 @@ import           Cardano.Ledger.Crypto
 import           Cardano.Ledger.SafeHash (extractHash)
 import qualified Cardano.Ledger.SafeHash as Ledger
 
-import           Control.Monad.IO.Class
 import           Control.Monad.Trans.Except
 import           Control.Monad.Trans.Except.Extra
 import qualified Data.ByteString as BS
 import           Data.Function
-import qualified Data.Text as Text
 import qualified Data.Text.Encoding as Text
 import qualified Data.Text.IO as Text
 
@@ -43,7 +41,7 @@ runGovernanceHashCmds (Cmd.GovernanceHashCmd args)=
 runGovernanceHashCmd :: ()
   => Cmd.GovernanceHashCmdArgs era
   -> ExceptT GovernanceHashError IO ()
-runGovernanceHashCmd Cmd.GovernanceHashCmdArgs { toHash } =
+runGovernanceHashCmd Cmd.GovernanceHashCmdArgs { toHash, moutFile } =
   -- TODO @smelc we probably want an option to write the computed hash to a file
   -- This can be done in a separate PR
   case toHash of
@@ -61,5 +59,9 @@ runGovernanceHashCmd Cmd.GovernanceHashCmdArgs { toHash } =
       let hash = Ledger.hashAnchorData $ Ledger.AnchorData $ Text.encodeUtf8 text
       printHash hash
   where
-    printHash :: Ledger.SafeHash StandardCrypto i -> ExceptT a IO ()
-    printHash = liftIO . putStr . Text.unpack . hashToTextAsHex . extractHash
+    printHash :: Ledger.SafeHash StandardCrypto i -> ExceptT GovernanceHashError IO ()
+    printHash hash = do
+      firstExceptT GovernanceHashWriteFileError $
+        newExceptT $ writeTextOutput moutFile text
+      where
+        text = hashToTextAsHex . extractHash $ hash

cardano-cli/src/Cardano/CLI/Types/Errors/GovernanceHashError.hs

@@ -8,10 +8,13 @@ import           Cardano.Api
 import           Cardano.Prelude (Exception (displayException), IOException)
 
 data GovernanceHashError
-  = GovernanceHashReadFileError FilePath IOException
+  = GovernanceHashReadFileError !FilePath !IOException
+  | GovernanceHashWriteFileError !(FileError ())
   deriving Show
 
 instance Error GovernanceHashError where
   displayError = \case
     GovernanceHashReadFileError filepath exc ->
       "Cannot read " <> filepath <> ": " <> displayException exc
+    GovernanceHashWriteFileError fileErr ->
+      displayError fileErr

cardano-cli/test/cardano-cli-golden/Test/Golden/Governance/Action.hs

@@ -10,6 +10,7 @@ import           Test.Cardano.CLI.Util
 import           Hedgehog (Property)
 import qualified Hedgehog.Extras.Test.Base as H
 import qualified Hedgehog.Extras.Test.Golden as H
+import qualified Hedgehog.Extras as H
 
 hprop_golden_governance_action_create_constitution :: Property
 hprop_golden_governance_action_create_constitution =
@@ -53,12 +54,18 @@ hprop_golden_conway_governance_action_view_constitution_json :: Property
 hprop_golden_conway_governance_action_view_constitution_json =
   propertyOnce . H.moduleWorkspace "tmp" $ \tempDir -> do
     stakeAddressVKeyFile <- H.note "test/cardano-cli-golden/files/input/governance/stake-address.vkey"
+    hashFile <- noteTempFile tempDir "hash.txt"
 
     actionFile <- noteTempFile tempDir "action"
 
-    proposalHash <- execCardanoCLI
+    -- We go through a file for the hash, to test --out-file
+    void $ execCardanoCLI
       [ "conway", "governance", "hash"
-      , "--text", "whatever "]
+      , "--text", "whatever "
+      , "--out-file", hashFile
+      ]
+
+    proposalHash <- H.readFile hashFile
 
     void $ execCardanoCLI
       [ "conway", "governance", "action", "create-constitution"

cardano-cli/test/cardano-cli-golden/files/golden/help.cli

@@ -6182,6 +6182,7 @@ Usage: cardano-cli conway governance hash
                                             | --file-binary FILE
                                             | --file-text FILE
                                             )
+                                            [--out-file FILE]
 
   Compute the hash to pass to the various --*-hash arguments of governance
   commands.

cardano-cli/test/cardano-cli-golden/files/golden/help/conway_governance_hash.cli

@@ -3,6 +3,7 @@ Usage: cardano-cli conway governance hash
                                             | --file-binary FILE
                                             | --file-text FILE
                                             )
+                                            [--out-file FILE]
 
   Compute the hash to pass to the various --*-hash arguments of governance
   commands.
@@ -11,4 +12,5 @@ Available options:
   --text TEXT              Text to hash as UTF-8
   --file-binary FILE       Binary file to hash
   --file-text FILE         Text file to hash
+  --out-file FILE          The output file.
   -h,--help                Show this help text

cardano-cli/test/cardano-cli-test/Test/Cli/Governance/Hash.hs

@@ -0,0 +1,42 @@
+{- HLINT ignore "Use camelCase" -}
+
+module Test.Cli.Governance.Hash where
+
+import           Control.Monad (void)
+
+import           Test.Cardano.CLI.Util
+
+import           Hedgehog (Property)
+import qualified Hedgehog as H
+import qualified Hedgehog.Extras as H
+
+hprop_governance_hash_trip :: Property
+hprop_governance_hash_trip =
+  propertyOnce $ do
+    governance_hash_trip_fun "foo"
+    governance_hash_trip_fun "longerText"
+    governance_hash_trip_fun "nonAscii: 你好"
+    governance_hash_trip_fun "nonAscii: à la mode de Cæn"
+
+-- Test that @cardano-cli conway governance hash --text > file1@ and
+-- @cardano-cli conway governance hash --text --out-file file2@ yields
+-- similar @file1@ and @file2@ files.
+governance_hash_trip_fun :: String -> H.PropertyT IO ()
+governance_hash_trip_fun input =
+  H.moduleWorkspace "tmp" $ \tempDir -> do
+    hashFile <- noteTempFile tempDir "hash.txt"
+
+    hash <- execCardanoCLI
+      [ "conway", "governance", "hash"
+        , "--text", input
+      ]
+
+    void $ execCardanoCLI
+      [ "conway", "governance", "hash"
+      , "--text", input
+      , "--out-file", hashFile
+      ]
+
+    hashFromFile <- H.readFile hashFile
+
+    H.diff hash (==) hashFromFile