can I safely clone perl lib to another location on a computer? - perl

I have my own personal perl instance, using perlbrew and a local cpan instance. I put in a bit of effort to get cpan to work for my local install. I've configured code and tested it using this perl.
I now want to ensure anyone on the computer can use the perl code I wrote, meaning ensuring that the cpan modules I used are available to all, even those that can't access my home directory.
Unfortunately, I can't configure and use cpan as root user. There are a few reasons why this would be difficult, but the biggest is that I am using my personal cert to authenticate myself as part of connecting to the CPAN repo (needed due to the configuration of the system). I don't want to make my cert available to everyone for connecting to CPAN.
I'm wondering if, instead of fixing the root cpan instance and trying to hunt down all the modules I'm using with cpan, I can simply copy the modules I already have. I'm running with the same perl version and on the same architecture, so the modules in my personal home directory should be the right ones.
The problem is that perllocal.pod seems to hard code locations relative to where my instal was done, so a simply copy paste is not enough. Is there another easy way, possible a perl utility, to copy my local CPAN modules and perl lib directory over to the root perl lib directory?

Probably, but why don't you just give them permission to your perlbrew-installed perl. Then just continue to use #!/home/ikegami/usr/perlbrew/perls/5.22.0t/bin/perl or whatever.

If you don't know exactly what you have installed, you could have a look at Dist::Surveyor
If you already know what all of your deps are, you can list them in a cpanfile and then take a snapshot with Carton and use the generated cpanfile.snapshot to install the correct versions in the new location

you can clone the whole CPAN to your server for everyone to install
minicpan -l ~/CPAN -r http://ppm.activestate.com/CPAN/ [-f]

Related

Installing an perl based web-app in extremely restricted environment

Because i have a long series of comments with #ikegami, I cleaning up the question, in a hope it will be more understandable. Unfortunately, english isn't my "main" language. :(
Let say, having an environment where:
no development tools are installed (no make, nor gcc or like)
perl is installed with its core packages, nothing more
no outgoing network access is allowed - e.g. the user couldn't use curl nor cpan to download/install perl dependencies
the user even doesn't have admin (root) rights
but want install and evaluate some perl based web-app, let call it as MyApp
The MyApp
doesn't uses any XS-based module. (at least, I hope - in the development me using plenv and cpanm, so never checked the installed dependencies in depth)
it is an pure PSGI app, the simple plackup app.psgi works OK
the app uses some data-files which should be included in the "deployment".
The main question is: how to prepare the MyApp, and the all used CPAN-modules, to be easily installed in such restricted environment?
The goal is:
i don't need save my efforts and my time
but i want save the user's time and want minimize the needed actions on his side, so the installation (deployment) should be simple-as-possible.
E.g. how to get an running web-app to the user's machine with minimum possible (his) steps.
- the simplest thing is could be something as:
- copy one file (zip, or tarbal)
- unpack it
- from the terminal execute some run.pl in the unpacked directory.
To get the above simple installation, my idea was the following:
1.) Create an tarball, and after the unpacking will contain 3 folders and 1 perl-script, let say:
myapp_repo/
myapp_repo/distlib #will contain all MyApp's perl modules also ALL used CPAN modules and their dependecies
myapp_repo/datafiles #will contain app-specific data files and such
myapp_repo/install.pl
myall_repo/lib #will contain modules directly used by the `install.pl`
2.) I will develop an install.pl script, and it will be used as the installer-tool, like
perl install.pl new /path/to/app_root
and it will (should):
create the all needed directories under the /path/to/app_root (especially the lib where the will install the perl modules)
will call "local" cpanm internally (from the myapp_repo/lib) to install the app's perl modules and their CPAN dependencies using only distribution files from the distlib.
will generate and install the needed runtime script and the app.psgi into the /path/to/app_root/bin
will install the needed data-files for the app.
3.) So, after this the user should be able to simply run:
/path/to/app_root/bin/plackup /path/to/app_root/bin/app.psgi
In short, the user should use:
the system-wide perl and the system-wide perl-core modules
and any other
runtime perl-scripts (like plackup)
and the required CPAN-modules
should be installed to an self-contained directory tree using only files (no net-access).
E.g. the install.pl should somewhat call internally the cpanm to achieve (as equivalent) for the following cpanm command
cpanm --mirror file://path/to/myapp_repo/distlib --mirror-only My::App
which, should install My::App and all dependencies without network access using only the files from the myapp_repo/distlib
Some questions:
Is possible to use cpanm (called as an locally installed module) without the make?
For creating the myapp_repo/distlib, me thinking about using Pinto. Is it the right tool for achieve the above?
forgot me something? or with other words:
Is the above an viable (read: working) way?
are are any other tools, which i could/should to use for simplifying the creation of such distribution tarball?
#ikegami suggesting some method:
- "install everything" in one fresh-directory on my machine
- transfer this self-contained directory to the target machine
It sound very good, because this directory could contain all the needed app-specific data-files too, unfortunately, I don't understand the details how his solution should be done.
The FatPacked solution looks interesting too - need learn about it.
Don't write your own make or installer. Just copy it make from a different machine (which is basically what apt/yum/etc do anyway, and which you'd have to do even if you wrote your own). You'd be able to use cpan in 5 minutes!
Also, that should allow you to install gcc if you need it (e.g. to install an XS module), although it doesn't sound like you do. If you do install gcc, I'd install my own perl to avoid having to deal with PERL5LIB.
Tools such as minicpan will allow you to install any module from CPAN without internet access. Of course, you can keep using the command you are already using it if mirrors the packages you need.
The above explains how to simply and quickly setup a machine so it can use cpan and thus install any module easily.
If you just want to install a specific module and its dependencies, you can completely avoid using cpan on the target machine. First, you need a fresh install of Perl (preferable of the same version as the one on the target system). Then, simply install the module to a fresh dir on your machine, and transfer that dir to the target machine. That's it; nothing else needs to be done. This even works for XS modules if the two machine are similar enough.
This is what ppm (ActiveState's Perl package manager) does.
Unfortunately, while this solution is almost as simple as the one above, it's not nearly as flexible, it doesn't run the test suite of the modules being installed, etc. It does have the advantage of not requiring the transfer of any binary (if you're not installing any XS modules).

Installing cpan or cpanm modules on a behind-firewall machine with no Internet connection

I've already read related threads like these, but they do not fully capture our situation.
This is on a firewalled machine. No net access. We can ftp files to folders and install modules from there.
We have CHMOD 777 for our users on some folders. We can install Perl modules if we locally build them by downloading the relevant .pm files. But when these files cannot install, we do not have any cpan or cpanm.
I'd like to install, for example, HTML::Restrict. If I do the download + install thing, the Restrict.pm gives me this error:
/lib/HTML/Restrict.PM:328: Unknown command paragraph "=encoding UTF-8"
Reading a bit online suggests that this could be an old Perl problem. We use 5.8.x. Our own dev machines have the luxury of 5.16.x and internet access so installing module is a cinch. Anyway, one of my older machines also has 5.8.x, and installing the module via cpanminus worked there (with internet).
So, question: is it possible to install "cpanminus" (cpanm) through FTP, then upload specific module files to the server through FTP too, and then go into shell and install modules via cpanm by pointing it to respective .pm files?
Thank you for any pointers.
You should take a look at perldoc perlmodinstall which goes into detail about how to install a module from its distribution. It follows what should be a familiar incantation
Decompress
Unpack
Build
Test
Install
Assuming you're on a Linux system, this commonly takes take the form of
gzip -d My-Module-Distribution.tar.gz
tar -xof My-Module-Distribution.tar
perl Makefile.PL
make
make test
make install
But after the Unpack stage you will often find a README file or other text file that will describe any unusual steps to be taken
Clearly some of these steps can be combined. For instance, most people will probably want to use
tar -xvfz My-Module-Distribution.tar.gz
to avoid having to invoke gzip separately. Likewise, the make system will force a build phase as a prerequisite if you use just
make test
without the preceding make
The linked document has a lot to say about how to install on other platforms, should you not be running a Linux variant
I still don't really understand your thinking, but you can get a stand-alone version of cpanm using curl. For instance
curl -sS --location https://cpanmin.us/ --output cpanm
then you should be able to just copy it to your target machine, put it on your PATH, and do
cpanm HTML-Restrict-2.2.2.tar.gz
but I doubt if you will find any change to the specific errors you are getting

CPAN first launching configuration

I'm taking a look into Perl as a total beginner. I want to try some CPAN modules.
When I run an install command on my Osx console, CPAN asks for a configuration with the following statement :
To install modules, you need to configure a local Perl library
directory or escalate your privileges. CPAN can help you by
bootstrapping the local::lib module or by configuring itself to use
'sudo' (if available). You may also resolve this problem manually if
you need to customize your setup.
What approach do you want? (Choose 'local::lib', 'sudo' or 'manual')
What is the difference between local::lib and sudo options ?
If I understand it well, it installs some modules locally on my computer. But I don't see any difference between the two config above.
If you use sudo, CPAN will use root to install the libraries in a central location where all users on the machine can access the files without any special configuration. If you use 'local::lib', it will create a library in your home directory and install the modules such that only perl programs that have been configured to look for modules in your home directory will find the modules.
Perl uses the special variable #INC to search for module paths. So you can install modules anywhere as long as you set #INC properly before you use them. This article explains the basics.
http://www.symkat.com/find-a-perl-modules-path
You can do all kinds of fun stuff with #INC; one of my favorite hacks it to put a function pointer in there and use custom perl code to lookup modules.
Good question. When you use local::lib, you can install Modules via CPAN User specific in an given directory. Assume you choose sudo as approach, you install Modules global.
Its like installing Node.js via npm. When you install a module with npm install -g <Modul>, its global installed and you can use it everywhere. But withouth that -g flag, its just available inside your current directory.
Its about the same here, except that you choose the default way of installing CPAN Modules.

How to install Perl offline

I have a Linux server that has no access to the internet (access is prevented by a firewall). I would like to install a new Perl. What are my options and what is the best way to do this? The system Perl (included in OS installation) must remain unchanged.
I have been using perlbrew and I think it is the best way to do an online installation. But all the steps involved in perlbrew seem to require internet access: you download it from the net, it downloads new Perl versions from the net etc. and I haven't found a glue how to make it work offline.
If perlbrew is out of question I could build Perl from source into a custom location on the server. I assume that this could end up being complicated, time-consuming and error-prone. And every time I update Perl I have make a new build manually.
There can also be other ways to install that I'm not currently aware of. And of course I could stick with the system Perl but it is an outdated version and I'm already using the new syntax features. Or I could start negotiations to change the firewall policy to allow internet access for perlbrew.
But all the steps involved in perlbrew seem to require internet access
Not if properly configured.
To install perlbrew itself off-line, install the App-perlbrew dist. Following its dependencies manually is a chore, so instead prepare a MiniCPAN mirror (with -p to include Perl dists), take it over to the target machine and configure CPAN to use the local mirror. Run cpan App::perlbrew to install.
After perlbrew is installed, run its mirror command to configure a CPAN mirror into $PERLBREWROOT/Config.pm. Edit this file to change it to the local MiniCPAN mirror. Drop Perl dist tarballs into $PERLBREWROOT/dists/.
Be aware that compiling Perl requires a working C compiler toolchain, and optionally the development files for libdb (BerkeleyDB) and gdbm. (Read the INSTALL file once over, even though perlbrew's autoconfiguration and Perl's configure.SH defaults hide these details from you.)
The compiler toolchain is probably much more difficult to procure off-line, unless the OS installation has already been used before for compiling other C stuff.
There's nothing that special about perlbrew. If you aren't going to use it to download the Perl sources, it's not saving you that much. Once you have the Perl sources, you just need to configure and install it:
% ./Configure -des -Dprefix=/path/to/installation
% make install
Once done, everything for that Perl is under that installation path.
I dislike perlbrew mostly because it hides from people how amazingly simple this task is so they feel like they can't do it on their own.
Have you considered attacking it from a different direction? Keeping this up-to-date is going to be a pain if you have to request internet access each time. Likewise, if you've missed out/misconfigured any packages in your CPAN mirror it's difficult to correct once you're actually trying to use them.
Perhaps just build a small VM with a cut-down linux + perl + modules. Keep that up-to-date at your end and just take the whole lot in on a USB stick. You'd have a known-working easy-to-setup installation.
What I personally do is using git checkout when I'm offline (and not on vacation). Once you have the whole git work directory, it's trivial to build any released version by checking out the tags:
git checkout v5.17.4
git clean -f # cleanup previously compiled .o files etc
sh ./Configure ...
Depending on how you can transfer files to your host, this can be handy, since you you can also setup a private git repo there so other computer can git push new commits to there.

How can Install multiple Perl versions without them tripping over each other's XS modules?

I would like to install several different versions of perl in my home directory. I tried using App::perlbrew, but XS modules from one version were causing segfaults in the other version. Is there any way to install multiple versions of perl and have them automatically keep their XS modules separate?
You can install each perl completely separate from any other perl installation. It's binaries and modules will be completely separate from each other. Essentially, when you install each perl you give it its own prefix:
$ ./Configure -des -Dprefix=/usr/local/perls/perl-5.12.1
Everything is installed under that prefix, and all of the programs in the bin/ will use that particular perl. I go into this in more depth in Effective Perl Programming.
From there, I make symlinks in my ~/bin to each of those programs and attach the version number to it, so I have ~/perl5.12.1, perldoc5.12.1, and so on. I don't ever have to choose to have a version in the way that perlbrew wants you to. I write more about this in Make links to per-version tools. in the Effective Perler blog.
You might be able to use local::lib for this, but it's really designed for you to work with one version of Perl and use one personal library directory. You can tell it to use another directory, but at that point it's really not saving you anything over the traditional way.