I have done a review of github and bitbucket as candidates for hosting GIT repositories for collaborative 
DAQ-type projects. Here is my impressions.

1. GIT as a software management tool seems to be a reasonable choice for DAQ-type projects. "master" 
repositories can be hosted at places like github or self-hosted (in the simplest case, only 
http://host/~user web access is required to host a git repository), for each "daq project" aka "experiment" 
one would "clone" the master repository, perform any local modifications as required, with full local 
version control, and when desired feed the changes back to the master repository as direct commits (git 
push), as patches posted to github ("pull requests") or patches emailed to the maintainers (git format-
patch).

2. Modern requirements for hosting a DAQ-type project include:
a) code repository (GIT, etc) with reasonably easy user access control (i.e. commit privileges should be 
assigned by the project administrators directly, regardless of who is on the payroll at which lab or who is 
a registered user of CERN or who is in some LDAP database managed by some IT departement 
somewhere).
b) a wiki for documentation, with similar user access control requirements.
c) a mailing list, forum or bug tracking system for communication and "community building"
d) an ability to web host large static files (schematics, datasheets, firmware files, etc)
e) reasonable web-based tools for browsing the files, looking at diffs, "cvs annotate/git blame", etc.

3. Both github and bitbucket satisfy most of these requirements in similar ways:

a) GIT repositories:
aa) access using git, ssh and https with password protection. ssh keys can be uploaded to the server, 
permitting automatic commits from scripts and cron jobs.
bb) anonymous checkout possible (cannot be disabled)
cc) user management is simple: participants have to self-register, confirm their email address, the project 
administrator to gives them commit access to specific git repositories (and wikis).
dd) for the case of multiple project administrators, one creates "teams" of participants. In this 
configuration the repositories are owned by the "team" and all designated "team administrators" have 
equal administrative access to the project.

b) Wiki:
aa) both github and bitbucket provide rudimentary wikis, with wiki pages stored in secondary git 
repositories (*NOT* as a branch or subdirectory of the main repo).
bb) github supports "markdown" and "mediawiki" syntax
cc) bitbucket supports "markdown" and "creole" syntax (all documentation and examples use the "creole" 
syntax).
dd) there does not seem to be any way to set the "project standard" syntax - both wikis have the "new 
page" editor default to the "markdown" syntax.
ee) compared to mediawiki (wikipedia, triumf daq wiki) and even plone, both github and bitbucket wikis 
lack important features:
1) cannot edit individual sections of a page, only the whole page at once, bad if you have long pages.
2) cannot upload images (and other documents) directly through the web editor/interface. Both wikis 
require that you clone the wiki git repository, commit image and other files locally and push the wiki git 
repo into the server (hopefully without any collisions), only then you can use the images and documents 
in the wiki.
3) there is no "preview" function for images - in mediawiki I can have small size automatically generated 
"preview" images on the wiki page, when I click on them I get the full size image. (Even "elog" can do this!)
ff) to be extra helpful, the wiki git repository is invisible to the normal git repository graphical tools for 
looking at revisions, branches, diffs, etc. While github has a special web page listing all existing wiki 
pages, bitbucket does not have such a page, so you better write down the filenames on a piece of paper.

c) mailing list/forum/bug tracking:
aa) both github and bitbucket implement reasonable bug tracking systems (but in both systems I do not 
see any button to export the bug database - all data is stuck inside the hosting provider. Perhaps there is 
a "hidden button" somewhere).
bb) bitbucket sends quite reasonable email notifications
cc) github is silent, I do not see any email notifications at all about anything. Maybe github thinks I do not 
want to see notices about my own activities, good of it to make such decisions for me.

d) hosting of large files: both git and wiki functions can host arbitrary files (compared to mediawiki only 
accepting some file types, i.e. Quartus pof files are rejected).

e) web based tools: thumbs up to both! web interfaces are slick and responsive, easy to use.

Conclusions:

Both github and bitbucket provide similar full-featured git repository hosting, user management and bug 
tracking.

Both provide very rudimentary wiki systems. Compared to full featured wikis (i.e. mediawiki), this is like 
going back to SCCS for code management (from before RCS, before CVS, before SVN). Disappointing. A 
deal breaker if my vote counts.

K.O.

Let me add my five cents:

We use bitbucket now since two months at PSI, and are very happy with it.

Pros:

- We like the GIT flow model (http://nvie.com/posts/a-successful-git-branching-model/). You can at the same time do hot fixes, have a "distribution 
version", and keep a development branch, where you can try new things without compromising the distribution.
- Nice and fast Web interface, especially the "blame" is lightning fast compared to SVN/CVS
- GIT is non-centralized, so your local clone of a repository contains everything. If bitbucket is down/asks for money, you can continue with your local 
repository and clone it to some other hosting service, or host it yourself
- SourceTree (http://www.sourcetreeapp.com/) is a nice GUI for Mac lovers. 
- Easy user management
- Free for academic use

Con:

- Wiki is limited as KO wrote, so it should not be used as a "full" wiki to replace Plone for example, just to annotate your project
- SVN revision number is gone. This is on purpose since it does not make sense any more if you keep several parallel branches (merging becomes a 
nightmare), so one has to use either the (random) commit-ID or start tagging again.

So I conclusion, I would say that it's time to switch MIDAS to GIT. We'll probably do that in July when I will be at TRIUMF.

/Stefan

And my 2ct:

Go for git!

I've been using git since 2007 or so, after cvs and svn. Git has some killer features which I can't miss any more:

* No central repo. Have all the history with you on the train.
* Branching and merging, with stable branches and feature branches.
  Happy hacking while my students do analysis on a stable version.
  Or multiple development branches for several features.
  And merging really works, including fixing up merge conflicts.
* "git bisect" for finding which commit introduced a (reproducible) bug.
* "gitk --all"

I use git for everything: Software, tex, even (Ooffice) Word documents.

Go for git. :-)

Randolf

Hi, thanks for your positive feedback. I have been using git for small private projects for a few years now
and I like it. It is similar to the old SCCS days - good version control without having to setup servers,
accounts, doodads, etc.

> * No central repo. Have all the history with you on the train.
> * Branching and merging, with stable branches and feature branches.
>   Happy hacking while my students do analysis on a stable version.
>   Or multiple development branches for several features.

This is the part that worries me the most. Without a "central" "authoritative" repository,
in just a few quick days, everybody will have their own incompatible version of midas.

I guess I am okey with your private midas diverging from mainstream, but when *I* end up
with 10 different incompatible versions just in *my* repository, can that be good?

>   And merging really works, including fixing up merge conflicts.

But somebody still has to do it. With a central repository, the problem takes care of
itself - each developer has to do their own merging - with svn, you cannot commit
to the head without merging the head into your code first. But with git, I can just throw
my changes int some branch out there hoping that somebody else would do the merging.
But guess what, there aint anybody home but us chickens. We do not have a mad finn here
to enforce discipline and keep us in shape...

As an example, look at the HADOOP/HDFS code development, they have at least 3 "mainstream"
branches going, neither has all the features combined together and each branch has bugs with
the fixes in a different branch. What a way to run a railroad.

> * "git bisect" for finding which commit introduced a (reproducible) bug.
> * "gitk --all"
>
> Go for git. :-)

Absolutely. For me, as soon as I can wrap my head around this business of "who does all the merging".

K.O.

Hi Konstantin,

> > * No central repo. Have all the history with you on the train.
> > * Branching and merging, with stable branches and feature branches.
> >   Happy hacking while my students do analysis on a stable version.
> >   Or multiple development branches for several features.
> 
> This is the part that worries me the most. Without a "central" "authoritative" repository,
> in just a few quick days, everybody will have their own incompatible version of midas.

No! This is probably one of the biggest misunderstandings of the git workflow.

You can of course _define_ one central repo: This is the one that you and Stefan decide to be "the source" (as
Linus does for the kernel). It's like the central svn repo: Only Stefan and you can push to it, and everybody
else will pull from it. Why should I pull MIDAS from some obscure source, when your "public" repo is available.

Look at the Linux Kernel: Linus' version is authoritative, even though everybody and his best friend has his
own kernel repo.

So, the main workflow does not change a lot: You collect patches, commit them, and "push" them to the central
repo. All users "pull" from this central repo. This is very much what svn offers.

> 
> I guess I am okey with your private midas diverging from mainstream, but when *I* end up
> with 10 different incompatible versions just in *my* repository, can that be good?

See above: _You_ define what the central repo is.

But: I _bet_ you will very soon have 10 versions in your personal repo, because _you choose_ to do so. It's
just SO much easier. The non-linear history with many branches is a _feature_. I can't live without it any more:


Looking at my MIDAS analyzer:

I have a "public" repo in /pub/git/lamb.git. This is where I publish my analyzer versions. All my collaborators
pull from this.

Then I have my personal repo in ~/src/lamb. 
This is where I develop. When I think something is ready for the public, I merge this branch into the public repo. 

Whenever I start to work on a new feature, I create a branch in my _local_ repo (~/src/lamb).  I can fiddle and
play, not affecting anybody else, because it never sees the public repo.
OK, collaborator A finds a bug. I switch to my local copy of the public version, fix the bug, and push the fix
to the publix repo. Then I go back to my (local) feature branch, merge the bug fix, and continue hacking.
Only when the feature is ready, I push it to the public repo.

Things get moe interesting as you work on several features simultaneously. You have e.g. 3 topic branches:
(a) is nearly ready, and you want a bunch of people to test it.
    push branch "feature (a)" to the public repo and tell the people which branch to pull.
(b) is WIP, you hack on it without affecting (a).
(c) is bug fixes which may or may not affect (a) or (b).
And so on.

You will soon discover the beauty of several parallel branches.

Plus, git merges are SO simple that you never think about "how to merge"

> 
> >   And merging really works, including fixing up merge conflicts.
> 
> But somebody still has to do it. With a central repository, the problem takes care of
> itself - each developer has to do their own merging - with svn, you cannot commit
> to the head without merging the head into your code first. But with git, I can just throw
> my changes int some branch out there hoping that somebody else would do the merging.
> But guess what, there aint anybody home but us chickens. We do not have a mad finn here
> to enforce discipline and keep us in shape...

See above: You will have the exact same workflow in git, if you like.




> As an example, look at the HADOOP/HDFS code development, they have at least 3 "mainstream"
> branches going, neither has all the features combined together and each branch has bugs with
> the fixes in a different branch. What a way to run a railroad.

I haven't look at this. All I can say: Branches are one of the best features.

> 
> > * "git bisect" for finding which commit introduced a (reproducible) bug.
> > * "gitk --all"
> >
> > Go for git. :-)
> 
> Absolutely. For me, as soon as I can wrap my head around this business of "who does all the merging".

Easy: YOU do it.

Keep going as in svn: Collect patches, and send them out.

And then, try "git checkout -b my_first_branch", hack, hack, hack,
"git merge master".

Best,

Randolf


> 
> K.O.

> * "git bisect" for finding which commit introduced a (reproducible) bug.

I did not know this command, so I read about it. This IS WONDERFUL! I had once (actually with MSCB) the case that a bug was introduced i the last 100 
revisions, but I did not know in which. So I checked out -1, -2, -3 revisions, then thought a bit, then tried -99, -98, then had the bright idea to try -50, then 
slowly converged. Later I realised that I should have done a binary search, like -50, if ok try -25, if bad try -37, and so on to iteratively find the offending 
commit. Finding that there is a command it git which does this automatically is great news.

Stefan

> > * "git bisect" for finding which commit introduced a (reproducible) bug.
> 
> I did not know this command, so I read about it. This IS WONDERFUL! I had once (actually with MSCB) the case that a bug was introduced i the last 100 
> revisions, but I did not know in which. So I checked out -1, -2, -3 revisions, then thought a bit, then tried -99, -98, then had the bright idea to try -50, then 
> slowly converged. Later I realised that I should have done a binary search, like -50, if ok try -25, if bad try -37, and so on to iteratively find the offending 
> commit. Finding that there is a command it git which does this automatically is great news.

even more so considering the nonlinear history (due to branching) in a regular git repo.

Hi All,

I set "/Analyzer/ODB Load" to true and analyzed a run in offline mode. After
that, I found the start time and stop time in /RunInfo did not reflect the
correct time as in online. How do I retrieve the correct start/stop time from
the ODB in offline mode?

Thanks!

Jimmy

> I set "/Analyzer/ODB Load" to true and analyzed a run in offline mode. After
> that, I found the start time and stop time in /RunInfo did not reflect the
> correct time as in online. How do I retrieve the correct start/stop time from
> the ODB in offline mode?

Most trees in the ODB are not loaded with "/Analyzer/ODB Load", since you might 
want to have the start/stop time of the offline analysis there for example 
(although I agree that the online start/stop time is more interesting). So you 
have several options:

- modify mana.c. There is a function odb_load(), which first locks the whole ODB 
and then unprotects "/Experiment/Run Parameters" for example. Just add three more 
lines for "/Runinfo".

- write a run summary when running online. After each run, write a summary with 
start/stop time, number of events, settings etc. into some file. I usually do this 
in the EOR routine of the online analyzer and write directly into a CSV file which 
I can import directly into Excel. There I can make filtering depending on certain 
parameters, like show me all runs with more than x events where setting y was 10.

- extract the ODB from the .mid file with "odbhist -e filename.mid" and look into 
that.

- The time stamp of each event is in UNIX time form (seconds since 1.1.1970), so 
you now exactly when each event was recorded.

Hope one of this helps...

- Stefan

Replacing the MIDAS status page with a custom status page documented at

https://midas.triumf.ca/MidasWiki/index.php/Custom_Page_Features#Replace_Status_Page_by_a_Custom_page

does not appear to be supported in the current MIDAS version. 

As two of my experiments use this feature may I suggest its reinstatement?

Suzannah

> Replacing the MIDAS status page with a custom status page documented at
> 
> https://midas.triumf.ca/MidasWiki/index.php/Custom_Page_Features#Replace_Status_Page_by_a_Custom_page
> 
> does not appear to be supported in the current MIDAS version. 
> 
> As two of my experiments use this feature may I suggest its reinstatement?

It still works, but is actually simpler. The status page is now a "dynamic" page, meaning mhttpd just servers an html file to 
the browser and everything is done in JavaScript there. The file for the status page is under midas/resources/status.html. 
You can easily change that file or replace it with a completely different (custom) file without having to change the ODB. 

There is only one potential problem. All midas html pages now have a certain structure, as written in 

https://midas.triumf.ca/MidasWiki/index.php/Custom_Page#How_to_use_the_standard_MIDAS_navigation_bars_on_your_cust
om_page

So if you have an existing custom status page, you might have to change it slightly to include the standard elements 
"mheader" and "msidenav". But this allows you to have the standard menu on your custom page and alerts displayed at the 
top row of your custom page (which was not possible before).

Once this works for you, it would be nice to adjust the documentation to reflect this new way.

Stefan

> > I think there sneaked in a little bug in the mhttpd: when starting an experiment
> > from scratch and starting the mhttpd, the Menu Buttons are missing

Ok, the original problem with a small bug in the javascript code for the menu buttons (fixed now),
but I was moved to implement something I wanted to do for a long time.

The menu configuration is now done through a subdirectory /experiment/menu. Each entry corresponds to 
one menu button. Set to "y" to show it, set to "n" to hide it.

Buttons are displayed in the same order as they are in ODB, to change the order of buttons,
change their order in ODB (odbedit command "move").

This fixes the long standing problem with adding new midas pages - they were not automatically added to 
the existing "menu buttons" lists. So for example when the "chat" page was added, I did not know about it 
for a long time (and some people still do not know about it's existence) because it is was not included in 
my  "/experiment/menu buttons" list in all my already existing experiments. When the "start" and 
"transition" pages were added, probably nobody knows that they exist.

Now new buttons for new pages are automatically added to the list (via mhttpd.cxx::init_menu_buttons()), 
the users have an option to hide them by setting their values to "n".

K.O.

> > > I think there sneaked in a little bug in the mhttpd: when starting an experiment
> > > from scratch and starting the mhttpd, the Menu Buttons are missing
> 
> Ok, the original problem with a small bug in the javascript code for the menu buttons (fixed now),
> but I was moved to implement something I wanted to do for a long time.
> 

Is this change back-wards compatible with an old ODB?  Ie, if I upgrade MIDAS, will it notice that I have the old-style key "/Experiment/Menu Buttons" 
and replace it equivalently set keys in /Experiment/Menu?  Or will it just continue to use the old-style ODB key?

> > > > I think there sneaked in a little bug in the mhttpd: when starting an experiment
> > > > from scratch and starting the mhttpd, the Menu Buttons are missing
> > 
> > Ok, the original problem with a small bug in the javascript code for the menu buttons (fixed now),
> > but I was moved to implement something I wanted to do for a long time.
> > 
> 
> Is this change back-wards compatible with an old ODB?  Ie, if I upgrade MIDAS, will it notice that I have the old-style key "/Experiment/Menu Buttons" 
> and replace it equivalently set keys in /Experiment/Menu?  Or will it just continue to use the old-style ODB key?

I am trying to keep some compatibility between the web pages and mhttpd. I think in most cases, old mhttpd should continue to work
against new web pages (assuming matching mhttpd.js & co). But old web pages would probably break against new mhttpd, mostly due
to the rapid pace of their development.

Anyhow, the midas web page forms menu buttons in this order:
/Experiment/Menu, if it does not exist, then:
/Experiment/menu buttons, if it does not exist, then
built in list of menu buttons, which includes all possible buttons, hardcoded in mhttpd.js.

In cooperation with mhttpd: new mhttpd
- will automatically create the tree /experiment/menu with all buttons disabled
- will complain about the existence of /expriment/menu buttons, instruct user to delete it.

So to answer the question:
after git pull, make, restart mhttpd, you will see all possible menu buttons and you will have to go
into the odb editor to disable the buttons you do not want to see (i.e. the mscb button).

I did it this way on purpose, to give old-time midas users an opportunity to discover
some of the newly added buttons and pages, like the "chat" page, or the "example" page. If I migrated
the existing "menu buttons" verbatim, to the new tree, I would not even today know
that the "chat" page exists (I do not think it was ever announced or described on this forum
or anywhere in the documentation).

K.O.

Hi Folks,

In last year's updates to MIDAS, the MIDAS sequencer has been broken out as a
separate program (rather than running as part of mhttpd).  We hope that this
change will make the sequencer operation more stable.

Before anyone gets too used to using the new sequencer program, I would like to
rename it.  Currently the program is called 'sequencer'; I would like to rename
it 'msequencer', to make it consistent with most other MIDAS programs.  If you
object to making this change, please say so in the next two weeks.

Documentation on the MIDAS sequencer can be found on the wiki:

https://midas.triumf.ca/MidasWiki/index.php/Sequencer

Note that there are still some tweaks that need to be made to the sequencer
webpage and mhttpd in order to handle this new sequencer program.

Cheers,
Thomas

Hearing no objections I changed the name of the program to msequencer.  Wiki
documentation updated.

> Hi Folks,
> 
> In last year's updates to MIDAS, the MIDAS sequencer has been broken out as a
> separate program (rather than running as part of mhttpd).  We hope that this
> change will make the sequencer operation more stable.
> 
> Before anyone gets too used to using the new sequencer program, I would like to
> rename it.  Currently the program is called 'sequencer'; I would like to rename
> it 'msequencer', to make it consistent with most other MIDAS programs.  If you
> object to making this change, please say so in the next two weeks.
> 
> Documentation on the MIDAS sequencer can be found on the wiki:
> 
> https://midas.triumf.ca/MidasWiki/index.php/Sequencer
> 
> Note that there are still some tweaks that need to be made to the sequencer
> webpage and mhttpd in order to handle this new sequencer program.
> 
> Cheers,
> Thomas

I am debugging the frequent problem where the run number is mysteriously
reset to zero. As a first step, I am commiting changes to mhttpd.c and midas.c:
- abort on obviously corrupted "run number < 0"
- abort on cm_transition() to run 0 (the only place where the run number is
explicitely written to ODB)
- in the mhttpd "Start run" form, reject user setting the run number to <= 0.

Here is the CVS diff:

===================================================================
RCS file: /usr/local/cvsroot/midas/src/mhttpd.c,v
retrieving revision 1.253
diff -r1.253 mhttpd.c
2451a2452,2457
>   if (run_number < 0)
>     {
>     cm_msg(MERROR, "show_elog_new", "aborting on attempt to use invalid
run number %d",run_number);
>     abort();
>     }
> 
2506a2513,2519
> 
>     if (run_number < 0)
>       {
>       cm_msg(MERROR, "show_elog_new", "aborting on attempt to use invalid
run number %d",run_number);
>       abort();
>       }
> 
3582a3596,3602
> 
>   if (run_number < 0)
>     {
>     cm_msg(MERROR, "show_form_query", "aborting on attempt to use invalid
run number %d",run_number);
>     abort();
>     }
> 
5730a5751,5756
>   if (rn < 0) // value "zero" is okey
>     {
>     cm_msg(MERROR, "show_start_page", "aborting on attempt to use invalid
run number %d",rn);
>     abort();
>     }
> 
9684a9711,9719
>       if (i <= 0)
>         {
>         cm_msg(MERROR, "interprete", "Start run: invalid run number %d",i);
>         memset(str,0,sizeof(str));
>         snprintf(str,sizeof(str)-1,"Invalid run number %d",i);
>         show_error(str);
>         return;
>         }
> 
Index: src/midas.c
===================================================================
RCS file: /usr/local/cvsroot/midas/src/midas.c,v
retrieving revision 1.193
diff -r1.193 midas.c
3786c3786
<         status = cm_transition(_requested_transition | TR_DEFERRED, 0,
str, 256, SYNC, FALSE);
---
>         status = cm_transition(_requested_transition | TR_DEFERRED, 0,
str, sizeof(str), SYNC, FALSE);
3906a3907,3912
>   if (run_number <= 0)
>     {
>     cm_msg(MERROR, "cm_transition", "aborting on attempt to use invalid
run number %d",run_number);
>     abort();
>     }
> 
16069a16076,16081
>     }
> 
>   if (run_number < 0)
>     {
>     cm_msg(MERROR, "el_submit", "aborting on attempt to use invalid run
number %d", run_number);
>     abort();

K.O.

> I am debugging the frequent problem where the run number is mysteriously
> reset to zero. As a first step, I am commiting changes to mhttpd.c and midas.c:
> - abort on obviously corrupted "run number < 0"
> - abort on cm_transition() to run 0 (the only place where the run number is
> explicitely written to ODB)
> - in the mhttpd "Start run" form, reject user setting the run number to <= 0.

- abort on cm_transition() from run 0 to 1 during auto restart in mlogger.

Cvs diff:

RCS file: /usr/local/cvsroot/midas/src/mlogger.c,v
retrieving revision 1.65
diff -r1.65 mlogger.c
3277a3278,3283
>         if (run_number <= 0)
>           {
>           cm_msg(MERROR, "main", "aborting on attempt to use invalid run
number %d", run_number);
>           abort();
>           }
> 

K.O.

In close cooperation with Stefan, I refactored and rewrote the MIDAS event
buffering code (bm_send_event, bm_flush_cache, bm_receive_event and bm_push_event).

The main goal of this update is to make sure the event buffering code does not
have any infinite loops: in the past, we have seen mlogger and some frontends
loop forever consuming 100% CPU in the event buffering code. This should now be
completely fixed.

As additional bonuses, the refactored code is easier to read, has less code
duplication and should be more robust. A few potential logical problems have
been corrected and one case of reproducible infinite looping has been fixed.

The new code has passed the low-level consumer-producer tests, but has not yet
been used in anger in any real experiment. One hopes any new bugs introduced
would cause outright failures and core dumps (rather than silent data corruption).

All are welcome to try the new code. If it explodes, please send me the error
messages, stack traces and core dumps.

K.O.

> In close cooperation with Stefan, I refactored and rewrote the MIDAS event
> buffering code (bm_send_event, bm_flush_cache, bm_receive_event and bm_push_event).
>
> All are welcome to try the new code. If it explodes, please send me the error
> messages, stack traces and core dumps.

Stefan quickly found one new error (a typoe in a check against infinite looping) and
then I found one old error present in the old code that caused event loss when the
buffer became exactly 100% full (0 bytes free).

Both errors are now fixed in svn commit 3294.

K.O.