leveldb: add torepr for descriptor

format/leveldb/leveldb_descriptor.go

@@ -15,7 +15,8 @@ import (
 	"github.com/wader/fq/pkg/scalar"
 )
 
-//go:embed leveldb_log.md
+//go:embed leveldb_descriptor.jq
+//go:embed leveldb_descriptor.md
 var leveldbDescriptorFS embed.FS
 
 func init() {
@@ -24,6 +25,7 @@ func init() {
 		&decode.Format{
 			Description: "LevelDB Descriptor",
 			DecodeFn:    ldbDescriptorDecode,
+			Functions:   []string{"torepr"},
 		})
 	interp.RegisterFS(leveldbDescriptorFS)
 }

format/leveldb/leveldb_descriptor.jq

@@ -0,0 +1,42 @@
+# TK(2023-12-07): in the output, object-properties are
+# sorted alphabetically... how can one prevent this
+# and keep the original order?
+def _leveldb_descriptor_torepr:
+  def _f:
+   ( if .type == "root" then
+      (
+        [
+          .value.blocks[].records[]
+          | {type: "record", value: .}
+          | _f
+        ]
+      )
+     elif .type == "record" then
+      (
+        if .value.header.record_type != "full" then
+          empty
+        else
+          [
+            .value.data.tags[]
+            | {type: "tag", value: {(.key): .value}}
+            | _f
+          ]
+        end
+      )
+     elif .type == "tag" then
+      (
+        .value
+        | if .comparator then (.comparator |= .data) else . end
+        | if ."new file" then (
+            ."new file".largest_internal_key |= .data
+            | ."new file".smallest_internal_key |= .data
+          ) else . end
+        | if ."compact pointer" then (
+            ."compact pointer".internal_key |= .data
+          ) else . end
+      )
+    end
+   );
+  ( {type: "root", value: .}
+  | _f
+  );

format/leveldb/leveldb_descriptor.md

@@ -1,7 +1,6 @@
 ### Limitations
 
-- fragmented non-"full" records are not decoded further.
-
+- fragmented non-"full" records are not merged and decoded further.
 
 ### Authors
 

format/leveldb/leveldb_log.md

@@ -1,6 +1,6 @@
 ### Limitations
 
-- individual records are not merged and its data further decoded.
+- fragmented non-"full" records are not merged and decoded further.
 
 ### Authors
 

format/leveldb/testdata/help_leveldb_descriptor.fqtest

@@ -9,3 +9,15 @@ Decode examples
   # Decode value as leveldb_descriptor
   ... | leveldb_descriptor
 
+Limitations
+===========
+- fragmented non-"full" records are not merged and decoded further.
+
+Authors
+=======
+- @mikez (https://github.com/mikez), original author
+
+References
+==========
+- https://github.com/google/leveldb/blob/main/doc/impl.md#manifest
+- https://github.com/google/leveldb/blob/main/db/version_edit.cc

format/leveldb/testdata/help_leveldb_log.fqtest

@@ -11,28 +11,7 @@ Decode examples
 
 Limitations
 ===========
-- individual records are not merged and its data further decoded.
-
-Authors
-=======
-- @mikez (https://github.com/mikez), original author
-
-References
-==========
-- https://github.com/google/leveldb/blob/main/doc/log_format.md
-leveldb_log: LevelDB Log decoder
-
-Decode examples
-===============
-
-  # Decode file as leveldb_log
-  $ fq -d leveldb_log . file
-  # Decode value as leveldb_log
-  ... | leveldb_log
-
-Limitations
-===========
-- individual records are not merged and its data further decoded.
+- fragmented non-"full" records are not merged and decoded further.
 
 Authors
 =======