[rfile] Introduce ListKeys() method #20056

silverweed · 2025-10-08T09:57:04Z

Followup of #19958. Other than addressing @pcanal's comments, this PR introduces the ListKeys() method, which iterates over the keys of some subdirectory.
They do so via an iterator that returns an abridged version of TKey, currently containing only barebones information (more may be added later).

Checklist:

tested changes locally
updated the docs (if necessary)

github-actions · 2025-10-08T11:49:06Z

Test Results

19 files 19 suites 3d 8h 51m 22s ⏱️
3 688 tests 3 687 ✅ 0 💤 1 ❌
68 375 runs 68 370 ✅ 0 💤 5 ❌

For more details on these failures, see this check.

Results for commit d4daafe.

♻️ This comment has been updated with latest results.

io/io/inc/ROOT/RFile.hxx

jblomer · 2025-10-09T11:45:42Z

io/io/inc/ROOT/RFile.hxx

+Querying this information can be done via RFile::GetKeys() or RFile::GetKeysNonRecursive. Reading an object's Key
+doesn't deserialize the full object, so it's a relatively lightweight operation.
+*/
+struct RFileKeyInfo {


I'm not sure this is the best name, because the keys are the same whether it is TFile or RFile. I'd probably prefer RFile::RKeyInfo or Detail::RKeyInfo... (not entirely sure about those two either).

io/io/inc/ROOT/RFile.hxx

io/io/src/RFile.cxx

pcanal · 2025-10-09T15:54:54Z

io/io/src/RFile.cxx

      throw ROOT::RException(R__FAIL("failed to open file " + std::string(path) + " for reading"));

+   if (tfile->IsRaw() || !tfile->IsBinary() || tfile->IsArchive())
+      throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));


Suggested change

throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));

throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT binary file"));

whether we want to hint on whether xml and archive file will be supported at some point is another question.

pcanal · 2025-10-09T15:55:20Z

io/io/src/RFile.cxx

      throw ROOT::RException(R__FAIL("failed to open file " + std::string(path) + " for updating"));

+   if (tfile->IsRaw() || !tfile->IsBinary() || tfile->IsArchive())
+      throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));


Suggested change

throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));

throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT binary file"));

pcanal · 2025-10-09T15:55:36Z

io/io/src/RFile.cxx

      throw ROOT::RException(R__FAIL("failed to open file " + std::string(path) + " for writing"));

+   if (tfile->IsRaw() || !tfile->IsBinary() || tfile->IsArchive())
+      throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));


Suggested change

throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));

throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT binary file"));

pcanal · 2025-10-09T15:59:29Z

io/io/inc/ROOT/RFile.hxx

+   std::string fName;
+   std::string fTitle;
+   std::string fClassName;
+   std::uint16_t fCycle = 0;


Here we choose to duplicate the information rather than forwarding it from the live TKey. What are the pros and cons?

pcanal · 2025-10-09T16:02:52Z

io/io/inc/ROOT/RFile.hxx

+(since they are a concept in the ROOT binary format). However they are for now only interacted with indirectly, via the
+use of filesystem-like string-based paths. If you Put an object in an RFile under the path "path/to/object", "object"
+will be stored under directory "to" which is in turn stored under directory "path". This hierarchy is encoded in the
+ROOT file itself and it can provide some optimization and/or conveniencies when querying objects.


Suggested change

ROOT file itself and it can provide some optimization and/or conveniencies when querying objects.

ROOT file itself and it can provide some optimization and/or conveniences when querying objects.

pcanal · 2025-10-09T16:08:52Z

io/io/inc/ROOT/RFile.hxx

   /// Flushes the RFile if needed and closes it, disallowing any further reading or writing.
   void Close();
+
+   /// Returns an iterable over all paths of objects written into this RFile starting at path "rootPath".


The sentence does not give wiggle room to include the case (flags & kListRecursive) == 0. We should add a conditional somewhere, for example

Suggested change

/// Returns an iterable over all paths of objects written into this RFile starting at path "rootPath".

/// Returns an iterable over all paths of objects written into this RFile starting at path "rootPath" (defaulting to also include the content of sub-directories)

(but the proposed words don't seem to match the first part (path vs directories))

pcanal · 2025-10-09T16:14:01Z

io/io/src/RFile.cxx

+
+      // Reconstruct the full path of the key
+      const auto &fullPath = dirPath + dirSep + key->GetName();
+      const auto nesting = fIterStack.size() - 1;


Suggested change

const auto nesting = fIterStack.size() - 1;

const std::uint16_t nesting = fIterStack.size() - 1;

To avoid the warnings:

comparison of integer expressions of different signedness: ‘const long unsigned int’ and ‘int’ [-Wsign-compare]

Alternatively fRootDirNesting could be made the same as decltype(fIterStack.size())

pcanal · 2025-10-09T16:53:32Z

io/io/src/RFile.cxx

   if (!tfile || tfile->IsZombie())
      throw ROOT::RException(R__FAIL("failed to open file " + std::string(path) + " for reading"));

+   if (tfile->IsRaw() || !tfile->IsBinary() || tfile->IsArchive())


Why is RFile sensitive to the backend (binary vs text) used by TFIle?

silverweed requested review from enirolf, hageboeck, hahnjo, jblomer and vepadulano October 8, 2025 09:57

silverweed self-assigned this Oct 8, 2025

silverweed added the in:I/O label Oct 8, 2025

silverweed requested a review from pcanal as a code owner October 8, 2025 09:57

silverweed force-pushed the rfile_02 branch 3 times, most recently from ed31e98 to a001f6d Compare October 8, 2025 15:00

jblomer reviewed Oct 9, 2025

View reviewed changes

silverweed added 2 commits October 9, 2025 15:17

[rfile] Some improvements to doc and tests; use Info for extension msg

0bdea40

[rfile] Throw exception for .zip files

d98d9b9

silverweed force-pushed the rfile_02 branch from a001f6d to 48d1ff7 Compare October 9, 2025 14:14

silverweed changed the title ~~[rfile] Introduce GetKeys() methods~~ [rfile] Introduce ListKeys() method Oct 9, 2025

silverweed force-pushed the rfile_02 branch from 48d1ff7 to 7f3f1db Compare October 9, 2025 14:15

[rfile] add ListKeys() method

d4daafe

silverweed force-pushed the rfile_02 branch from 7f3f1db to d4daafe Compare October 9, 2025 14:18

pcanal reviewed Oct 9, 2025

View reviewed changes

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

[rfile] Introduce ListKeys() method #20056

[rfile] Introduce ListKeys() method #20056

silverweed commented Oct 8, 2025 •

edited

Loading

Uh oh!

github-actions bot commented Oct 8, 2025 •

edited

Loading

Uh oh!

Uh oh!

Uh oh!

jblomer Oct 9, 2025

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

pcanal Oct 9, 2025

Uh oh!

Uh oh!

	throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT file"));
	throw ROOT::RException(R__FAIL("Opened file " + std::string(path) + " is not a ROOT binary file"));

	ROOT file itself and it can provide some optimization and/or conveniencies when querying objects.
	ROOT file itself and it can provide some optimization and/or conveniences when querying objects.

	/// Returns an iterable over all paths of objects written into this RFile starting at path "rootPath".
	/// Returns an iterable over all paths of objects written into this RFile starting at path "rootPath" (defaulting to also include the content of sub-directories)

	const auto nesting = fIterStack.size() - 1;
	const std::uint16_t nesting = fIterStack.size() - 1;

[rfile] Introduce ListKeys() method #20056

Are you sure you want to change the base?

[rfile] Introduce ListKeys() method #20056

Conversation

silverweed commented Oct 8, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Checklist:

Uh oh!

github-actions bot commented Oct 8, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Test Results

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

silverweed commented Oct 8, 2025 •

edited

Loading

github-actions bot commented Oct 8, 2025 •

edited

Loading