I have a remote repository which updates the jar once in 5 hours without changing the version number.Pom file is not able to update as the version is same.Each time I need to manually delete.Is there any way i can get the latest files using the settings.xml.
Do you control this remote repository? If yes, then use a "-SNAPSHOT" version number.
Or ask the people who do control the repository to do that. It's the correct way to tell Maven that the dependency is in a state of flux.
And if you're unable/unwilling to do that, write yourself a batch/shell script to invoke Maven, which deletes the file beforehand.
I have a remote repository which updates the jar once in 5 hours without changing the version number. Pom file is not able to update as the version is same. Each time I need to manually delete. Is there any way i can get the latest files using the settings.xml.
No, there is no way to achieve this. Once an artifact with a fixed version (as opposed to SNAPSHOT) has been downloaded, it won't be downloaded again, unless you remove it from your local repository. Actually, re-releasing a jar without changing its fixed version number is an EVIL practice and must be avoided. This is just not how maven works and when doing this, it's impossible to predict which version people are really using (without asking them to explicitly remove the jar from their local repository which is a very weak practice) and this will lead to unpredictable results.
The right way to handle frequent releases is either to change the version number (and updating POMs accordingly) or to use a SNAPSHOT version which is the common approach used during development. By definition, SNAPSHOT version will be downloaded if a newer version is made available in the remote repository. This is what you are looking for and this is the maven way to manage this situation. For more details about SNAPSHOT, see the chapter 9.3.1.2. SNAPSHOT Versions of Maven: The Definitive Guide.
You can set element updatePolicy to always for a repository in your settings.xml:
<profiles>
<profile>
<id>default</id>
<repositories>
<repository>
<releases>
<enabled>true</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
<updatePolicy>always</updatePolicy>
</snapshots>
<id>snapshots.jboss.org</id>
<name>Snapshot JBoss Repository for Maven</name>
<url>http://snapshots.jboss.org/maven2/</url>
<layout>default</layout>
</repository>
</repositories>
</profile>
</profiles>
Related
I'm working with pdfbox-app-2.0.0-20140226.103319-176.jar. But i notice there is a continues development and Apache PDFBox application published new version frequently. In the officials’ side I can see pdfbox-app-2.0.0-**-182,183,184.jar in the following URL. I try to get with the pdfbox-app-2.0.0-**-177,178,179,180,181.jars using pom.xml file, but no luck. Could you please help me to get pdfbox-app-2.0.0-**-177,178,179,180,181.jars.
Could you please help me to get pdfbox-app-2.0.0-**-177,178,179,180,181.jars.
No, no one could (except in the case the source repository were tagged for every snapshot, or you are so lucky to find somebody who have saved that specific version).
You should work with public repository, but if you need a not yet published functionality you could work with snapshot repository. In such a case you have to be aware you are using an unstable, rapidly-evolving, version so if your program works today it might not work tomorrow because the code has evolved: in general this "problem" is a wanted behavior when working with unstable versions.
In fact that problem notifies you that you are counting on a functionality that will not exists in the future at the same way as it existed in your used (old) version, and the earlier you discover the error the better your are able to change your work without too much pain.
In order to work with a snapshot repository add (in your case):
<project>
<modelVersion>4.0.0</modelVersion>
<repositories>
<repository>
<id>ApacheSnapshot</id>
<name>Apache Repository</name>
<url>https://repository.apache.org/content/groups/snapshots/</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
then add the dependency:
<dependency>
<groupId>org.apache.pdfbox</groupId>
<artifactId>pdfbox-app</artifactId>
<version>2.0.0-SNAPSHOT</version>
</dependency>
More generally speaking working effectively with SNAPSHOT is to be intended in the context of a development process where developer teams communicate and project managers are in charge of making deadlines respected.
We are using maven 2.2.1 and are pretty happy with how the things are going.
Recently we've started to use dependency versions' ranges like this:
<dependency>
<!-- com.google.inject.Guice -->
<groupId>com.google.inject</groupId>
<artifactId>guice</artifactId>
<version>[3,4)</version>
</dependency>
But now I am facing a problem that maven checks for new versions of every such dependency at every build, which makes builds painfully slow:
[INFO] artifact com.google.inject:guice: checking for updates from internal
[INFO] artifact com.google.inject:guice: checking for updates from central
Here is how my repositories declaration looks like:
<repositories>
<repository>
<id>internal</id>
<url>http://internal.repo.local/nexus/content/repositories/releases</url>
</repository>
</repositories>
I've checked repository configuration as far as I can understand, looked through default values for <repository/> section and parent POM inheritance.
I have already tried changing updatePolicy with no success. Looks like all policies are working with only SNAPSHOT management and are ignored for version checks.
I've found a workaround of -o command line option, but... I would like to check for external version at least sometimes and idea of creation cron-based maven scheduling that updates local repository daily does not sound for as an appropriate solution.
First, as a previous commenter said, your build isn't reproducible with build ranges... which is the whole point of Maven. I hope you understand the significance of that, so I'll just answer your question.
Simply set the update policy of the repository:
<repositories>
<repository>
<id>internal</id>
<url>http://internal.repo.local/nexus/content/repositories/releases</url>
<releases>
<enabled>true</enabled>
<updatePolicy>always</updatePolicy>
</releases>
<snapshots>
<enabled>true</enabled>
<updatePolicy>always</updatePolicy>
</snapshots>
</repository>
</repositories>
EDIT: I answered the original question out of context, sorry.
The best way to answer this is to figure out why Maven is updating every day. This may be caused by your ranged dependency, or it may be a bug in Maven. I will let you do the footwork on that...
I think what you're actually trying to get at is, "How do I keep maven from going out to central every time I do a build and slowing me down?" I had this exact problem while working overseas, the internet connection was very slow. We setup a nexus proxy, and I had to figure out a way to force all lookups to hit the proxy.
Change the <updatePolicy> to something that suits your needs. Daily would probably work unless you have more specific needs.
Next, edit your settings.xml and add this section:
</activeProfiles>
<mirrors>
<mirror>
<id>internal-mirror</id>
<url>http://internal.repo.local/nexus/content/repositories/releases</url>
<mirrorOf>*</mirrorOf>
</mirror>
</mirrors>
</settings>
This will force all dependency lookups to go through your internal nexus instance, hitting the nexus cache, and immensely speeding up your build.
How can i make a project jar release and maven repository strucuture(md5hash,distribution pom,etc) to put this in my own repository? Maven have a plugin to do it? Note, i need to generate this structure in my local machine, i don't have CI and others to do it!
Hopes!!!
Check the deploy plugin, I think this is what you're looking for. Quoting the documentation:
As a repository contains more than the artifacts (POMs, the metadata, MD5 and SHA1 hash files...), deploying means not only copying the artifacts, but making sure all this information is correctly updated. It's the reponsibility of the deploy plugin.
You'll need to declare a <distributionManagement> element to use it, something like this:
<distributionManagement>
<repository>
<id>internal.repo</id>
<name>MyCo Internal Repository</name>
<url>Host to Company Repository</url>
</repository>
</distributionManagement>
Where the url can be a "local" file://.
And if the question is about installing a (third party) jar in your local repository (the question is not totally clear), have look at the Maven Install Plugin, install:install and install:install-file both admit a createChecksum optional parameters.
Let's say I have one project with the following POM:
<groupId>com.mine</groupId>
<artifactId>coreJar</artifactId>
<packaging>jar</packaging>
<version>0.0.1-SNAPSHOT</version>
And then in another project I always want to reference the latest SNAPSHOT:
<dependencies>
<dependency>
<groupId>com.mine</groupId>
<artifactId>coreJar</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
...
<dependencies>
But instead of 0.0.1-SNAPSHOT, I want it to always grab the latest SNAPSHOT version. In the past you could use LATEST, but this has since been deprecated (for reasonable reasons).
I do understand you can specify versions, such as:
[1.5,)
But I could never get it to work with a "-SNAPSHOT":
[0.0.1,)-SNAPSHOT // Doesn't work!
The question then is how do I get maven to grab the latest SNAPSHOT in my other project?
Another option (which I use) is to include the following in your pom.xml. updatePolicy tag will force maven to always use latest snapshot from this repo.
<repositories>
<repository>
<id>you-snapshots</id>
<url>http://host/nexus/repos/snapshots</url>
<snapshots>
<updatePolicy>always</updatePolicy>
</snapshots>
<releases>
<updatePolicy>always</updatePolicy>
</releases>
</repository>
</repositories>
p.s. I always configure all repos in pom.xml because we use several CI servers and it will be quite hard to configure all of them (I am lazy...)
Doc on settings.xml updatePolicy for reference.
The frequency for downloading updates - can be "always", "daily" (default), "interval:XXX" (in minutes) or "never" (only if it doesn't exist locally).
Use
mvn -U, --update-snapshots
Forces a check for updated releases and snapshots on remote repository
A few words about dependency ranges and SNAPSHOT dependencies (quoting the Dependency Mediation and Conflict Resolution design document):
Incorporating SNAPSHOT versions into the specification
Resolution of dependency ranges should not resolve to a snapshot (development version) unless it is included as an explicit boundary. There is no need to compile against development code unless you are explicitly using a new feature, under which the snapshot will become the lower bound of your version specification. As releases are considered newer than the snapshot they belong to, they will be chosen over an old snapshot if found.
So, to answer your question, the only way to use a SNAPSHOT with dependency ranges is as boundary and you won't get higher SNAPSHOT versions automatically by design (which really makes sense).
Personally, I don't like to use dependency ranges because I find that it can lead to build reproducibility issues and makes the build more fragile. I do not recommend them.
Just in case, upgrading the SNAPSHOT version typically means that you are releasing some code and the maven release plugin provides support for that (see the Updating POM Versions).
There is a Versions plugin for Maven which allows you to update your pom to the latest greatest SNAPSHOTS in visible repositories. It does this by inspecting your pom and comparing against remote repositories and then modifying as required.
It is a useful tool but I would definitely like to see an equivalent to the deprecated LATEST option. I find this kind of dependency particularly useful in continuous integration scenarios.
use mvn install -U
u must use this to force maven to get the latest snapshots
It's
<version>[0.0-SNAPSHOT,)</version>
In case you want to update your SNAPSHOT releases inside Eclipse (when using m2e / m2eclipse), right click the affected project, then select "Maven" -> "Update Project..." -> "OK" (with selected project causing problems).
my problem with maven is that if the maven repository is not responding, one cannot build. It seems to fetch every "mvn package" time some poms, which won't change, because they are of the same version.
How can I say to maven that please don't look them up from server, and instead download them permanetly to offline repository?
Thanks!
You can run maven with the -o flag:
-o,--offline Work offline
This will cause Maven to never look for dependencies in remote repositories. On the other hand, your build will fail if the dependencies are not found in the local repository.
You can configure the repository to only check for updates occasionally, or never by setting the updatePolicy element on the repository declaration. From the settings documentation:
The frequency for downloading updates - can be "always", "daily" (default), "interval:XXX" (in minutes) or "never" (only if it doesn't exist locally).
Adding the following to your POM or the settings will configure the central repository to only download if the artifact doesn't exist locally:
<repositories>
<repository>
<id>central</id>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
</repository>
</repositories>
If the repository in question is an internal remote repository, you need to ensure the maven-metadata.xml is configured correctly in the remote repository or Maven will attempt to download it each time. The simplest way to do this is to use a repository manager that will manage the metadata automatically