Hi, I wanted to open a ROOT File from GitLab repo. I tried:
TFile* file = TFile::Open(“url/filename”);
and
TFile* file = TFile::Open(“url/filename”, “WEB”);
But It didn’t find the file.
How can I do it?
Imanol
Please read tips for efficient and successful posting and posting code
ROOT Version: Not Provided
Platform: Not Provided
Compiler: Not Provided
Try:
root -l -q -b -e 'TFile *f = TFile::Open("http://root.cern.ch/files/atlas.root"); f->ls();'
root -l -q -b -e 'TFile *f = TFile::Open("https://root.cern.ch/files/atlas.root"); f->ls();'
It works, but I don’t understand the difference between this and my code. Maybe the GitLab server is spoiling something?
Imanol
You may need something like: "http://myusername:mypasswd@my.server/my/file.root"
Make sure that “wget” works, e.g.: wget http://myusername:mypasswd@my.server/my/file.root
Here’s a simple GitHub test (note: the “View raw” link is used):
root -l -q -b -e 'TFile *f = TFile::Open("https://github.com/root-project/root/blob/master/tutorials/gallery.root?raw=true"); f->ls();'
That GitHub test works, I guess that the difference is the permission, my repository is private. How can I add this?
Make sure you can retrieve your file with the “wget” and/or “curl”. Then ROOT should be able to retrieve it, too.
I can retrieve it with “wget” but ROOT is giving me the error:
Error in : can not open file “path/file” with davix: Result HTTP 404 : File not found after 3 attempts (18)
Have you added the “token”, e.g.:
"https://my.git.lab/api/v4/projects/MyRepositoryID/repository/files/MyFile.root/raw?private_token=MyReadApiOrReadRepositoryToken"
@Axel We need someone who could have a look at it.
What do you mean? Where should I add this?
How exactly do you get your file with “wget”?
Do I understand it right that when you:
wget https://gitlab.cern.ch/path/filename.root
you really get the raw “filename.root” (which you can then open in ROOT)?
@Axel … ROOT 6.26/10 on a Ubuntu 22.04 / x86_64 / GCC 11.3.0 fails in a simple test:
gitlab.cern.ch → HepMC/HepMC3 → python/test/inputIO4.root
This is a public repository, so “wget” doesn’t need any tokens:
wget "https://gitlab.cern.ch/api/v4/projects/hepmc%2FHepMC3/repository/files/python%2Ftest%2FinputIO4.root/raw" -O inputIO4.root
wget "https://gitlab.cern.ch/api/v4/projects/6751/repository/files/python%2Ftest%2FinputIO4.root/raw" -O inputIO4.root
Unfortunately, ROOT fails:
root -l -q -b -e 'TFile *f = TFile::Open("https://gitlab.cern.ch/api/v4/projects/hepmc%2FHepMC3/repository/files/python%2Ftest%2FinputIO4.root/raw");'
root -l -q -b -e 'TFile *f = TFile::Open("https://gitlab.cern.ch/api/v4/projects/6751/repository/files/python%2Ftest%2FinputIO4.root/raw");'
Even if I try to use a “Personal Access Token” (a “read_repository” or “read_api” one):
root -l -q -b -e 'TFile *f = TFile::Open("https://gitlab.cern.ch/api/v4/projects/hepmc%2FHepMC3/repository/files/python%2Ftest%2FinputIO4.root/raw?private_token=AReadRepositoryOrReadApiToken");'
root -l -q -b -e 'TFile *f = TFile::Open("https://gitlab.cern.ch/api/v4/projects/6751/repository/files/python%2Ftest%2FinputIO4.root/raw?private_token=AReadRepositoryOrReadApiToken");'
In all cases, I get the following:
Error in <TDavixFile::Init>: file https://gitlab.cern.ch/api/v4/projects/.../repository/files/python%2Ftest%2FinputIO4.root/raw is truncated at 0 bytes: should be 2127856, trying to recover
Warning in <TDavixFile::Init>: no keys recovered, file has been made a Zombie
root -l -q -b -e 'TFile *f = TFile::Open("https://gitlab.cern.ch/hepmc/HepMC3/-/raw/master/python/test/inputIO4.root?inline=false");' works more or less well 
@Axel Could you please post the relevant link to GitLab documentation?
The one I know is:
GitLab → API Docs → REST API resources → Repository files API → Get raw file from repository
I just went here
Then there’s the “Download” button on the right, I took its URL. Note that GitLab is no full featured web server - this isn’t as fast / efficient as a regular Apache / nginx etc.
@Axel Could you please try “your method” with some “private GitLab repository” (which requires a “private_token” to retrieve files)?
Sorry, I just decided to use another strategy, so this is no longer necessary. Thank you for your help
This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.