Maven fails to get SNAPSHOT builds from repository

Question

Our internal repository (Artifactory) now contains both the stable builds as well as SNAPSHOT versions of our internal libraries.

For stable builds there has never been a problem of downloading anything from the repository.

However, when I add a -SNAPSHOT, Maven claims to be unable to find the dependency, even though it is most definitely in the repository.

If I build and deploy the dependency locally (i.e. into my local repo) all works normally.

Basically, this works:

<dependency>
  <groupId>com.example</groupId>
  <artifactId>ourlibrary</artifactId>
  <version>1.0.0</version>
</dependency>

and this doesn't:

<dependency>
  <groupId>com.example</groupId>
  <artifactId>ourlibrary</artifactId>
  <version>1.0.1-SNAPSHOT</version>
</dependency>

Even though both versions were built the same way and deployed (as far as I can possibly tell) correctly to the repository.

The error:

Missing:
----------

1) com.example:ourlibrary:jar:1.0.1-SNAPSHOT,

  Try downloading the file manually from the project website.

  Then, install it using the command:
      mvn install:install-file -DgroupId=com.example -DartifactId=ourlibrary -Dversion=1.0.1-SNAPSHOT, -Dpackaging=jar -Dfile=/path/to/file

  Alternatively, if you host your own repository you can deploy the file there:
      mvn deploy:deploy-file -DgroupId=com.example -DartifactId=ourlibrary -Dversion=1.0.1-SNAPSHOT, -Dpackaging=jar -Dfile=/path/to/file -Durl=[url] -DrepositoryId=[id]

  Path to dependency:
        1) com.example:product:war:2.0.0-SNAPSHOT
        2) com.example:ourlibrary:jar:1.0.1-SNAPSHOT,

While this sounds similar to this question, the resolution arrived at there does not apply to my case.

Any insights into this issue would be greatly appreciated.

Edit

Running with -X (as John V. suggested) revealed the following:

[DEBUG] Skipping disabled repository central
[DEBUG] ourlibrary: using locally installed snapshot
[DEBUG] Skipping disabled repository central
[DEBUG] Using mirror: http://repo.example.com/repo (id: repo.example.com)
[DEBUG] Artifact not found - using stub model: Unable to download the artifact from any repository

  com.example:ourlibrary:pom:1.0.1-SNAPSHOT

from the specified remote repositories:
  repo.example.com (http://repo.example.com/repo)


[DEBUG] Using defaults for missing POM com.example:ourlibrary:pom:1.0.1-SNAPSHOT:compile
[DEBUG]   com.example:ourlibrary:jar:1.0.1-SNAPSHOT:compile (selected for compile)

Solution 1

Two thoughts come to mind:

1. The path structure in your internal repository for your artifact is incorrect. I suggest running the maven command with -X parameter. It will display the maven's attempt at downloading the files. Get the line that has your repository as the url and try and look for it yourself.

   The path should look like

   /com/example/ourlibrary/1.0.1/ourlibrary-1.0.1-SNAPSHOT.jar

2. You didnt include your repository as a repository in your pom.xml

Solution 2

Typically you have a separate snapshots url from releases url. Just different paths in the same repository, but listed as separate repositories in the pom. The one for snapshots needs to have snapshots enabled, and the one for releases has snapshots disabled:

<repositories>
        <repository>
            <id>central</id>
            <url>
                http://<releases-url>
            </url>
            **<snapshots>
                <enabled>false</enabled>
            </snapshots>**
        </repository>

        <repository>
            <id>snapshots</id>
            <url>
                http://<snapshots-url>
            </url>
            <snapshots>
                **<enabled>true</enabled>**
                <!-- never, daily, interval:X (where X is in minutes) or always -->
                <!--<updatePolicy>daily</updatePolicy> -->
            </snapshots>
            <releases>
                <enabled>false</enabled>
            </releases>
        </repository>
    </repositories>