Implement parsing of tracing configuration

README.md

@@ -150,14 +150,27 @@ The flag names, metavars and help text match those historically accepted by
 `cardano-node`, so existing operator scripts keep working. You can inspect the
 parsed options with `cabal run cardano-config -- resolve --help`.
 
-## Tracing options are **not** parsed by this library
-
-Tracing is **not** parsed: it is owned by the node's tracing system (hermod /
-`trace-dispatcher`) and given under a single top-level `HermodTracing` key whose
-value is a path to a separate file. The key is recognised and captured opaquely
-(it appears in the schema), but its contents are not interpreted here. The
-authoritative schema lives in
-[`hermod-tracing`](https://github.com/IntersectMBO/hermod-tracing).
+## Tracing options are owned by `trace-dispatcher`
+
+Tracing is owned by the node's tracing system (hermod / `trace-dispatcher`),
+given under a single top-level `HermodTracing` key whose value is **either** a
+path to a separate file holding the tracing configuration **or** that
+configuration object inline. This library does not define or validate the shape
+of that object — the authoritative schema lives in
+[`hermod-tracing`](https://github.com/IntersectMBO/hermod-tracing), so the
+configuration schema describes `HermodTracing` only as "a path or a JSON
+object".
+
+Instead, the parser hands the `HermodTracing` value to `trace-dispatcher`'s own
+parser (`readConfiguration`), which resolves it into a `TraceConfig`: a file
+reference is read via `FromFile` (after resolving the path to its canonical
+location), an inline object via `FromJSONObject`.
+
+The resolved `TraceConfig` is carried through to the final `NodeConfiguration`
+(as `tracingConfiguration :: Maybe TraceConfig`), so a consumer of the library
+gets the tracing configuration already parsed, and `cardano-config resolve`
+emits it back under the `HermodTracing` key (as an inline object). It is
+`Nothing`/absent when the configuration has no `HermodTracing` key.
 
 ## Mandatory keys
 

cabal.project

@@ -17,33 +17,6 @@ index-state:
 packages:
   .
 
--- cardano-ledger at current master (provides the genesis types we decode here).
--- Kept to the minimum set of subdirs we actually depend on; add more only if the
--- solver requires them.
-source-repository-package
-  type: git
-  location: https://github.com/IntersectMBO/cardano-ledger
-  tag: 29c7e3040621f323f3af27fd4e89a223ba429021
-  --sha256: sha256-XPXfHvYjuzN0ASL/z4HwWJwDPQn7vJbTPlEa5zV3w9k=
-  subdir:
-    eras/byron/ledger/impl
-    eras/byron/crypto
-    eras/byron/ledger/executable-spec
-    eras/byron/chain/executable-spec
-    eras/shelley/impl
-    eras/allegra/impl
-    eras/mary/impl
-    eras/alonzo/impl
-    eras/babbage/impl
-    eras/conway/impl
-    eras/dijkstra/impl
-    libs/cardano-ledger-core
-    libs/cardano-ledger-binary
-    libs/cardano-data
-    libs/vector-map
-    libs/non-integral
-    libs/small-steps
-
 -- Ensures colourized output from test runners
 test-show-details: direct
 tests: true
@@ -73,6 +46,7 @@ if impl(ghc >=9.14)
     , canonical-json:containers
     , cborg:base
     , cborg:containers
+    , cborg-json:base
     , constrained-generators:QuickCheck
     , dependent-map:containers
     , dictionary-sharing:containers
@@ -91,3 +65,41 @@ if impl(ghc >=9.14)
 constraints:
   -- Happy version 2.2.1 fails to compile haskell-src-exts
   , happy < 2.2.1
+
+-- cardano-ledger at current master (provides the genesis types we decode here).
+-- Kept to the minimum set of subdirs we actually depend on; add more only if the
+-- solver requires them.
+source-repository-package
+  type: git
+  location: https://github.com/IntersectMBO/cardano-ledger
+  tag: 29c7e3040621f323f3af27fd4e89a223ba429021
+  --sha256: sha256-XPXfHvYjuzN0ASL/z4HwWJwDPQn7vJbTPlEa5zV3w9k=
+  subdir:
+    eras/byron/ledger/impl
+    eras/byron/crypto
+    eras/byron/ledger/executable-spec
+    eras/byron/chain/executable-spec
+    eras/shelley/impl
+    eras/allegra/impl
+    eras/mary/impl
+    eras/alonzo/impl
+    eras/babbage/impl
+    eras/conway/impl
+    eras/dijkstra/impl
+    libs/cardano-ledger-core
+    libs/cardano-ledger-binary
+    libs/cardano-data
+    libs/vector-map
+    libs/non-integral
+    libs/small-steps
+
+-- trace-dispatcher (hermod tracing) — provides the tracing configuration parser
+-- (ConfigSource/readConfiguration) used to resolve the HermodTracing key.
+-- Pinned to the merge commit after hermod-tracing#18 (mkarg/config-source).
+source-repository-package
+  type: git
+  location: https://github.com/IntersectMBO/hermod-tracing
+  tag: 3d7aeb85d9ef01df48a44c751e45609b4c6dea00
+  --sha256: sha256-r4bVm4x2akrCLcg5f0TG6aovCGqNnZkiiBckA3YCz7Q=
+  subdir:
+    trace-dispatcher

cardano-config.cabal

@@ -97,6 +97,7 @@ library internal
     scientific,
     text,
     time,
+    trace-dispatcher,
     transformers,
     yaml,
 

defaults/HermodTracing.json

@@ -0,0 +1,79 @@
+{
+  "ApplicationName": null,
+  "Forwarder": null,
+  "MetricsPrefix": "cardano.node.metrics.",
+  "Options": {
+    "": {
+      "backends": [
+        "Stdout MachineFormat",
+        "EKGBackend"
+      ],
+      "detail": "DNormal",
+      "severity": "Notice"
+    },
+    "BlockFetch.Client.CompletedBlockFetch": {
+      "maxFrequency": 2
+    },
+    "BlockFetch.Decision": {
+      "severity": "Silence"
+    },
+    "ChainDB": {
+      "severity": "Info"
+    },
+    "ChainDB.AddBlockEvent.AddBlockValidation": {
+      "severity": "Silence"
+    },
+    "ChainDB.AddBlockEvent.AddBlockValidation.ValidCandidate": {
+      "maxFrequency": 2
+    },
+    "ChainDB.AddBlockEvent.AddedBlockToQueue": {
+      "maxFrequency": 2
+    },
+    "ChainDB.AddBlockEvent.AddedBlockToVolatileDB": {
+      "maxFrequency": 2
+    },
+    "ChainDB.CopyToImmutableDBEvent.CopiedBlockToImmutableDB": {
+      "maxFrequency": 2
+    },
+    "ChainSync.Client": {
+      "severity": "Warning"
+    },
+    "Forge.Loop": {
+      "severity": "Info"
+    },
+    "Forge.StateInfo": {
+      "severity": "Info"
+    },
+    "LedgerMetrics": {
+      "severity": "Silence"
+    },
+    "Mempool": {
+      "severity": "Info"
+    },
+    "Net.ConnectionManager.Remote": {
+      "severity": "Info"
+    },
+    "Net.ErrorPolicy": {
+      "severity": "Info"
+    },
+    "Net.InboundGovernor": {
+      "severity": "Warning"
+    },
+    "Net.InboundGovernor.Remote": {
+      "severity": "Info"
+    },
+    "Net.Mux.Remote": {
+      "severity": "Info"
+    },
+    "Net.PeerSelection": {
+      "severity": "Silence"
+    },
+    "Resources": {
+      "severity": "Silence"
+    },
+    "Startup.DiffusionInit": {
+      "severity": "Info"
+    }
+  },
+  "PrometheusSimpleRun": null
+}

schemas/config.legacy-one-file.schema.json

@@ -236,10 +236,20 @@
             "type": "string"
         },
         "HermodTracing": {
-            "description": "Tracing configuration as a path to a separate file holding it. Consumed by the node tracing system (trace-dispatcher), not parsed or validated by cardano-config.",
-            "format": "path",
-            "title": "HermodTracing",
-            "type": "string"
+            "anyOf": [
+                {
+                    "format": "path",
+                    "title": "String",
+                    "type": "string"
+                },
+                {
+                    "additionalProperties": {},
+                    "title": "Object",
+                    "type": "object"
+                }
+            ],
+            "description": "Tracing configuration, given as a path to a separate file holding it or as that configuration object inline. Consumed by the node tracing system (trace-dispatcher), which owns its schema; not described further by cardano-config.",
+            "title": "HermodTracing"
         },
         "LedgerDB": {
             "description": "The LedgerDB configuration\nLedgerDB",

schemas/config.schema.json

@@ -97,10 +97,20 @@
             "title": "ConsensusConfig"
         },
         "HermodTracing": {
-            "description": "Tracing configuration as a path to a separate file holding it. Consumed by the node tracing system (trace-dispatcher), not parsed or validated by cardano-config.",
-            "format": "path",
-            "title": "HermodTracing",
-            "type": "string"
+            "anyOf": [
+                {
+                    "format": "path",
+                    "title": "String",
+                    "type": "string"
+                },
+                {
+                    "additionalProperties": {},
+                    "title": "Object",
+                    "type": "object"
+                }
+            ],
+            "description": "Tracing configuration, given as a path to a separate file holding it or as that configuration object inline. Consumed by the node tracing system (trace-dispatcher), which owns its schema; not described further by cardano-config.",
+            "title": "HermodTracing"
         },
         "LocalConnectionsConfig": {
             "anyOf": [

src/Cardano/Configuration.hs

@@ -86,6 +86,8 @@ module Cardano.Configuration
     -- * Configuration file
   , File.NodeConfigurationFromFile
   , File.TracingConfiguration (..)
+  , File.TracingConfigSource (..)
+  , File.TraceConfig
   , File.parseConfigurationFiles
   , File.ConfigWarning (..)
   , File.renderConfigWarning
@@ -123,6 +125,12 @@ data NodeConfiguration = NodeConfiguration
   , localConnectionsConfig :: File.LocalConnectionsConfig Identity
   , testingConfiguration :: File.TestingConfiguration Identity
   , mempoolConfiguration :: File.MempoolConfiguration Identity
+  , tracingConfiguration :: File.TraceConfig
+  -- ^ The tracing configuration resolved from the top-level @HermodTracing@ key
+  -- by @trace-dispatcher@'s parser (see 'File.resolveTracingConfiguration'), or
+  -- 'File.defaultCardanoTracingConfig' when no @HermodTracing@ key is present.
+  -- Carried through unchanged from the file-parse result so consumers get the
+  -- parsed 'File.TraceConfig'.
   , byronGenesisConfig :: ByronGenesisConfig
   -- ^ The parsed Byron genesis.
   , shelleyGenesisConfig :: ShelleyGenesis
@@ -302,6 +310,7 @@ resolveConfigurationWith checks cli file = do
         , localConnectionsConfig = localConnections
         , testingConfiguration = testing
         , mempoolConfiguration = mempool
+        , tracingConfiguration = File.tracingConfiguration file
         , byronGenesisConfig = File.byronGenesisConfig file
         , shelleyGenesisConfig = File.shelleyGenesisConfig file
         , alonzoGenesisConfig = File.alonzoGenesisConfig file

src/Cardano/Configuration/File.hs

@@ -31,6 +31,9 @@ module Cardano.Configuration.File
   , TestingConfiguration (..)
   , MempoolConfiguration (..)
   , TracingConfiguration (..)
+  , TracingConfigSource (..)
+  , TraceConfig
+  , defaultCardanoTracingConfig
 
     -- * Resolving components
   , finalizeNetwork
@@ -69,6 +72,11 @@ import Cardano.Configuration.File.Protocol
 import Cardano.Configuration.File.Storage
 import Cardano.Configuration.File.Testing
 import Cardano.Configuration.File.Tracing
+  ( TracingConfigSource (..)
+  , TracingConfiguration (..)
+  , defaultCardanoTracingConfig
+  , resolveTracingConfiguration
+  )
 import Cardano.Configuration.Genesis
   ( GenesisReadError
   , genesisErrorFile
@@ -83,6 +91,7 @@ import Cardano.Ledger.BaseTypes (StrictMaybe (..), maybeToStrictMaybe, strictMay
 import Cardano.Ledger.Conway.Genesis (ConwayGenesis)
 import Cardano.Ledger.Dijkstra.Genesis (DijkstraGenesis)
 import Cardano.Ledger.Shelley.Genesis (ShelleyGenesis)
+import Cardano.Logging.Types (TraceConfig)
 import Control.Exception (throwIO)
 import Data.Aeson (FromJSON, Value)
 import qualified Data.Aeson.Key as K
@@ -126,10 +135,14 @@ data NodeConfigurationFromFileF f
   , localConnectionsConfig :: f (LocalConnectionsConfig StrictMaybe)
   , testingConfiguration :: f (TestingConfiguration StrictMaybe)
   , mempoolConfiguration :: f (MempoolConfiguration StrictMaybe)
-  , tracingConfiguration :: TracingConfiguration
-  -- ^ Tracing keys, captured opaquely; see 'TracingConfiguration'. Unlike the
-  -- other components this is never read from a sub-file: the node's tracing
-  -- system resolves its own @HermodTracing@ file indirection.
+  , tracingConfiguration :: TraceConfig
+  -- ^ The tracing configuration referenced by the top-level @HermodTracing@ key,
+  -- resolved by @trace-dispatcher@'s own parser ('resolveTracingConfiguration'):
+  -- a @HermodTracing@ file path is read from that file, an inline object is read
+  -- directly. When no @HermodTracing@ key is present it falls back to
+  -- 'defaultCardanoTracingConfig', so a tracing configuration is always present.
+  -- Its schema is owned by @trace-dispatcher@, not described here (see
+  -- 'TracingConfiguration').
   , byronGenesisConfig :: ByronGenesisConfig
   -- ^ The parsed Byron genesis (read from the @ByronGenesisFile@).
   , shelleyGenesisConfig :: ShelleyGenesis
@@ -210,7 +223,11 @@ parseConfigurationVersion1 root minNodeVer configValue = do
   localConnections <- parseSection root configValue "LocalConnectionsConfig"
   testing <- parseSection root configValue "TestingConfig"
   mempool <- parseSection root configValue "MempoolConfig"
+  -- The @HermodTracing@ value is captured (as a file path or an inline object)
+  -- and then handed to trace-dispatcher's own parser, which resolves it to a
+  -- 'TraceConfig' — reading the referenced file, or the inline object directly.
   tracing <- runCodec Nothing "Tracing" configValue
+  traceConfig <- resolveTracingConfiguration root tracing
   -- The genesis files referenced by the configuration are read and decoded
   -- here, so that JSON resolution happens entirely within this library.
   let byronCfg = byronGenesis protocol
@@ -238,7 +255,7 @@ parseConfigurationVersion1 root minNodeVer configValue = do
       , localConnectionsConfig = Identity localConnections
       , testingConfiguration = Identity testing
       , mempoolConfiguration = Identity mempool
-      , tracingConfiguration = tracing
+      , tracingConfiguration = traceConfig
       , byronGenesisConfig = byronGenesisData
       , shelleyGenesisConfig = shelleyGenesisData
       , alonzoGenesisConfig = alonzoGenesisData