Can I parameterise the build machine? - jenkins

I'm trying to create a branch builder job. Our build servers are usually busy running nightly master builds, so I was thinking I could set people's personal machines up as slaves to Jenkins, and have them run the branch builder locally, kicked off from Jenkins
When I try and put a parameter in the machine restriction list, I get and error:
(pending—There are no nodes with the label ‘${BuildMachine}’)
Where BuildMachine was a selection of which machine to build on.
Is this possible, or is the list supposed to be restricted to all available machines only?

Sounds like you're talking about "traditional" jobs, like Freestyle, Maven, or Multijob (as opposed to Pipeline or Multibranch Pipeline). Please let me know if that's not the case, as the answer will likely be very different.
The restriction list does not allow you to use a parameter/variable (or even a wildcard or regex). Instead, you should take a look at the Node and Label parameter plugin:
This plugin adds two new parameter types to job configuration - node and label, this allows to dynamically select the node where a job/project should be executed.
Once installed:
Go to the job configuration and check This project is parameterized.
From the Add Parameter dropdown, select Node.
You can set the parameter name, choose a default node, and optionally allow all or a subset of nodes to be selected.
When you next run the job, you'll be able to select the node from a dropdown.
Caveat: Once a node/label parameter is added, the "Restrict where this project can be run" entry will be ignored; probably best to uncheck the selection to avoid confusion.

Related

Jenkins: How a job runs on a specific node with no label specified?

I understand that using labels can tie a project to a node. But, I am confused with our existing Jenkins configurations. The project core runs on slave10. But, the "Restrict where this project can be run" is unchecked, and the Label Expression is not specified. The labels in the slave10 configuration is not specified either. The question is how the job runs on slave10 with no label specified?
Under Manage Nodes, click Configure for any of your Nodes and review the Usage settings. Some of your nodes may have been configured with
Usage: Only build jobs with label expressions matching this node
Whilst other nodes may be configured with
Usage: Use this node as much as possible
By appropriate configuration of your nodes, it means you will only need to specify Label Expression for the exceptional cases.

How I can run single Jenkins job by previously defined rules

I'd like to get a hint how (which plugin) it is possible run SINGLE Jenkins job by the user chosen way. User MUST be able to choose the job he/she wants to run and choose the rule of execution:
E.g:
Create only jar files;
Create jars and send them over ssh
Create jars, generate documentation, etc...
I've found out a few plugins (Artifactory, Release plugin) but seems they don't support such logic.
I know that such thing can be implemented by creating several jobs, but this would require additional disk space.
Many Thanks!
In order to solve my issue, I've decided to create a few Jenkins jobs with the same custom workspace. So that, when a IT engineer runs any of these "connected" (which have the same workspace) jobs the workspace is updated (have a look at the CVS rules for your job) and that's why we avoid wasting of space.
Additionally, its (job) behaviour can be configured easily => the sets of rules (shell scripts, gradle, batch etc) and their sequence in order to achieve the desired result.
The last advantage, but not the least one, is that the security (access control) is still very easy to configure.
I think, that is the correct way.

Jenkins multiple builds from the same project in different slave nodes

Can I queue multiple builds from the same project in different slaves nodes and only one build per node? is there any plugin to do it?
You can use a matrix-project
The Configuration Matrix allows you to specify what
steps to duplicate, and create a multiple-axis graph
of the type of builds to create.
Which also supports a NodeLabel plugin.
This plugin adds two new parameter types to job
configuration - node and label, this allows to
dynamically select the node where a job/project
should be executed.
This combination will allow you to bind one configuration to selected (or all) nodes
Thanks to all of you, specially to KeepCalmAndCarryOn,he give me a good hits to solve the problem.
Finally I have installed Throttle Concurrent Builds Plugin and I have set the following options on the job config:

Jenkins schedule multiple versions of the same build

I have a project that has 3-5 different mercurial branches going at all times. I want to schedule a weekly Jenkins test to run our tests on all relevant branches.
What I want, I think, is a parameterized build, with the branch name as the parameter, and then to have a list of branches, and once a week, run the parameterized build with each of the parameters in the list.
However, I see that you can't send parameters into a triggered build. I assume that there is a plugin for this. Is job Generator the correct plugin? Is there something better?
I should mention that currently, we are doing this with multiple SCMs, and having the body of the build have a sh loop that runs through each directory and runs the tests. This is really inefficient, and a pain to maintain...
I can suggest one solution but it couldn't be called elegant.
Firstly, you need create multi-configuration project (aka Matrix project).
In this project you need declare one node (it can be already existed master node)
And one type of axis (for example BRANCH - be careful don't use Jenkins Set Environment Variables variables) with values corresponding for each branch (for example default, testing, devel, etc).
After you need add in your project build action in which you need check environment variable (previously declared $BRANCH) and discover for which branch this build was launched (the main idea is illustrated by example with using bash).
And finally you need manually get sources from corresponding branch.
Next build steps can be the same for all branches.
This approach have set of drawbacks:
1. You can not triggered this project by changes in repository (you can check using Mercurial plugin only one branch).
2. All subprojects will be rebuilt even if they have not changed.
3. Appropriate only for statically defined branches.
4. Not elegant.
But it has one advantage versus parameterized build:
1. All artifacts (and build logs) of branches is stored in separated directories (because they are separate subprojects).

Jenkins and multi-configuration (matrix) jobs

Why are there two kinds of jobs for Jenkins, both the multi-configuration project and the free-style project project? I read somewhere that once you choose one of them, you can't convert to the other (easily). Why wouldn't I always pick the multi-configuration project in order to be safe for future changes?
I would like to setup a build for a project building both on Windows and Unix (and other platforms as well). I found this question), which asks the same thing, but I don't really get the answer. Why would I need three matrix projects (and not three free-style projects), one for each platform? Why can't I keep them all in one matrix, with platforms AND (for example) gcc version on one axis and (my) software versions on the other?
I also read this blog post, but that builds everything on the same machine, with just different Python versions.
So, in short: how do most people configure a multi-configuration project targeting many different platforms?
The two types of jobs have separate functions:
Free-style jobs: these allow you to build your project on a single computer or label (group of computers, for eg "Windows-XP-32").
Multi-configuration jobs: these allow you to build your project on multiple computers or labels, or a mix of the two, for eg Windows-XP, Windows-Vista, Windows-7 and RedHat - useful for checking compatibility or building for multiple platforms (qt programs?)
If you have a project which you want to build on Windows & Unix, you have two options:
Create a separate free-style job for each configuration, in which case you have to maintain each one individually
You have one multi-configuration job, and you select 2 (or more) labels/computers/slaves - 1 for Windows and 1 for Unix. In this case, you only have to maintain one job for the build
You can keep the your gcc versions on one axis, and software versions on another. There is no reason you should not be able to.
The question that you link has a fair point, but one that does not relate to your question directly: in his case, he had a multi-configuration job A, which - on success - triggered another job B. Now, in a multi-configuration job, if one of the configuration fails, the entire job fails (obviously, since you want your project to build successfully on all your configurations).
IMHO, for building the same project on multiple platforms, the better way to go is to use a multi-configuration style job.
Another option is to use a python build step to check the current OS and then call an appropriate setup or build script. In the python script, you can save the updated environment to a file and inject the environment again using the EnvInject plugin for subsequent build steps. Depending on the size of your build environment, you could also use a multi-platform build tool like SCons.
You could create a script (e.g. build) and a batch file (e.g. build.bat) that get checked in with your source code. In Jenkins in your build step you can call $WORKSPACE/build - Windows will execute build.bat whereas Linux will run build.
An option is to use user-defined axis combined with slaves(windows, linux, ...), so you need to add a filter for each combination and use the Conditional BuildStep Plugin to set the build step specific for each plataform(Executar shell, Windows command, ...)
This link has a tutorial but it is in portuguese, but it's easy to work it out based on image...
http://manhadalasanha.wordpress.com/2013/06/20/projeto-de-multiplas-configuracoes-matrix-no-jenkins/
You could use the variable that jenkins create when you define a configuration matrix axis. For example:
You create a slave axis with name OSTYPE and check the two slaves (Windows and Linux). Then you create two separate build steps and check for the OSTYPE environment variable.
You could use a improved script language instead, like python, which is multi-platform and can achieve the same functionality independent of the slaves' name and in just one build step.
If you go the matrix route with Windows and something else, you'll want the XShell plugin. You just create your two build scripts such as "build.bat" for cmd and "build" for bash, and tell XShell to run "build". The right one will be run in each case.
A hack to have batch files run on Windows and shell scripts on Unix:
On Unix, make batch files exit with 0 exit status:
ln -s /bin/true /bin/cmd
On Windows, either find a true.exe, name it sh.exe and place it somewhere in the PATH.
Alternatively, if you have any sh.exe installed on Windows (From Cygwin, Git, or other source), add this to the top of the shell script in Jenkins:
[ -n "$WINDIR" ] && exit 0
Why wouldn't you always pick the multi-configuration job type?
Some reasons come to mind:
Because jobs should be easy to create and configure. If it is hard to configure any job in your environment, you are probably doing something wrong outside the scope of the jenkins job. If you are happy that you managed to create that one job and it finally runs, and you are reluctant to do this whole work again, that's where you should try to improve.
Because multi configuration jobs are more complex. They usually require you to think about both the main job and the different sub job variables, and they tend to grow in complexity to a level beyond being manageable. So in a single job scenario, you'd probably waste thoughts on not using that complexity, and when extending the build variables, things might grow in the wrong direction. I'd suggest using the simple jobs as default, and the multi configuration jobs only if there is a need for multiple configurations.
Because executing multi configuration jobs might need more job slots on the slaves than single jobs. There will always be a master job that is executed on a special, invisible slot (that's no problem by itself) and triggers the sub jobs, but if these sub jobs do themselves trigger sub jobs, you might easily end in a deadlock if there are more sub jobs than slots, and some sub jobs trigger again sub jobs that then cannot execute because there are no more open slots. This problem might be circumvented by using some configuration setup on the slaves, but it is present and might only occur if several multi jobs run concurrently.
So in essence: The multi configuration job is a more complex thing, and because complexity should be avoided unless necessary, the regular freestyle job is a better default.
If you want to select on which slave you run the job, you need to use multi-configuration project (otherwise you won't be able to select/limit slaves on which you run it – there are three ways to do it, however I've tried them all (Tie plugin works only for master job, Restrict in Advanced Project Options is not rock-safe trigger as well so you want to use Slave axis that is proven to work correctly today.)

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