未從Nexus加載Maven SNAPSHOT版本

Question

我們的環境中運行着一個Sonatype Nexus，其中配置了另一個Nexus作為代理存儲庫。 當我們消耗依賴項時，我們會向Nexus求助。 直到昨天，當我向我們的項目中添加了新的依賴項時，這一切都很好。

看來Maven不能正確解析已部署的快照版本。 在maven日志中，我可以看到它正在下載maven-metadata.xml，但是當它嘗試下載包含我們的二進制文件的zip文件時，它不會用當前快照版本替換-SNAPSHOT

> mvn -f My.Product.dependencies.xml process-resources -DConfiguration=AnyConfig -U -X

[DEBUG] Could not find metadata com.company.team:My.New.Dependency:2.2-SNAPSHOT/maven-metadata.xml in local (d:\Maven\repositories)
[DEBUG] Using connector WagonRepositoryConnector with priority 0 for http://buildserver:8082/nexus/content/groups/company
Downloading: http://buildserver:8082/nexus/content/groups/company/com/company/team/My.New.Dependency/2.2-SNAPSHOT/maven-metadata.xml
Downloaded: http://buildserver:8082/nexus/content/groups/company/com/company/team/My.New.Dependency/2.2-SNAPSHOT/maven-metadata.xml (850 B at 13.2 KB/sec)
[DEBUG] Reading resolution tracking file d:\Maven\repositories\com\company\team\My.New.Dependency\2.2-SNAPSHOT\resolver-status.properties
[DEBUG] Writing resolution tracking file d:\Maven\repositories\com\company\team\My.New.Dependency\2.2-SNAPSHOT\resolver-status.properties
[DEBUG] Could not find metadata com.company.team:My.New.Dependency:2.2-SNAPSHOT/maven-metadata.xml in local (d:\Maven\repositories)
[DEBUG] Using connector WagonRepositoryConnector with priority 0 for http://buildserver:8082/nexus/content/groups/company
Downloading: http://buildserver:8082/nexus/content/groups/company/com/company/team/My.New.Dependency/2.2-SNAPSHOT/maven-metadata.xml
Downloaded: http://buildserver:8082/nexus/content/groups/company/com/company/team/My.New.Dependency/2.2-SNAPSHOT/maven-metadata.xml (850 B at 55.3 KB/sec)
[DEBUG] Reading resolution tracking file d:\Maven\repositories\com\company\team\My.New.Dependency\2.2-SNAPSHOT\resolver-status.properties
[DEBUG] Writing resolution tracking file d:\Maven\repositories\com\company\team\My.New.Dependency\2.2-SNAPSHOT\resolver-status.properties
...
Downloading: http://buildserver:8082/nexus/content/groups/company/com/company/team/My.New.Dependency/2.2-SNAPSHOT/My.New.Dependency-2.2-SNAPSHOT-vs2010-40-AnyCpu-Release.zip
[DEBUG] Reading resolution tracking file d:\Maven\repositories\com\company\team\My.New.Dependency\2.2-SNAPSHOT\My.New.Dependency-2.2-SNAPSHOT-vs2010-40-AnyCpu-Release.zip.lastUpdated
[DEBUG] Writing resolution tracking file d:\Maven\repositories\com\company\team\My.New.Dependency\2.2-SNAPSHOT\My.New.Dependency-2.2-SNAPSHOT-vs2010-40-AnyCpu-Release.zip.lastUpdated
[INFO] ------------------------------------------------------------------------
...
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] My.Client.App  FAILURE [1.922s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.687s
[INFO] Finished at: Thu Oct 13 09:54:24 CEST 2016
[INFO] Final Memory: 9M/177M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal on project My.Client.App: Could not resolve dependencies for project com.company.team2:My.Client.App:pom:7.0-SNAPSHOT: The following artifacts could not be resolved: com.company.team:My.New.Dependency:zip:vs2010-40-AnyCpu-Release:2.2-SNAPSHOT: Could not find artifact com.company.team:My.New.Dependency:zip:vs2010-40-AnyCpu-Release:2.2-SNAPSHOT in company (http://buildserver:8082/nexus/content/groups/company) -> [Help 1]

maven-metadata.xml正確包含快照版本信息：

<?xml version="1.0" encoding="UTF-8"?>
<metadata modelVersion="1.1.0">
  <groupId>com.company.team</groupId>
  <artifactId>My.New.Dependency</artifactId>
  <version>2.2-SNAPSHOT</version>
  <versioning>
    <snapshot>
      <timestamp>20161011.235855</timestamp>
      <buildNumber>102</buildNumber>
    </snapshot>
    <lastUpdated>20161011235855</lastUpdated>
    <snapshotVersions>
      <snapshotVersion>
        <extension>pom</extension>
        <value>2.2-20161011.235855-102</value>
        <updated>20161011235855</updated>
      </snapshotVersion>
      <snapshotVersion>
        <classifier>vs2010-40-AnyCPU-Release</classifier>
        <extension>zip</extension>
        <value>2.2-20161011.235855-102</value>
        <updated>20161011235855</updated>
      </snapshotVersion>
    </snapshotVersions>
  </versioning>
</metadata>

當我檢查從中下載內容的文件夾的目錄列表時，那里的2.2-20161011.235855-102版本正確存在：

來自同一存儲庫的所有其他依賴項都可以很好地工作，只是不會下載新引入的依賴項。 目前，讓我感到瘋狂的是，Maven沒有像實際的快照版本號那樣替換-SNAPSHOT，就像其他所有依賴項所做的那樣。 我還嘗試了Nexus UI中的“過期緩存”和“更新索引”選項，但沒有幫助。 是什么導致Maven從實際版本號退回到-SNAPSHOT？ 也沒有日志條目可以解釋這一點。

Answer 1

在嘗試了一百萬種東西並將其他依賴項的配置與新依賴項進行比較之后，我終於發現了問題：工件ID（分類器）區分大小寫。 在我的客戶端POM文件中，我指的是vs2010-40-AnyCpu-Release但部署的是vs2010-40-AnyCPU-Release （請注意大寫的AnyC PU ）。

在日志文件中，您可以看到它嘗試下載小寫AnyCpu文件。 在將其更改為大寫之后，它起作用了。

Answer 2

你有一個文件

My.New.Dependency-2.2-SNAPSHOT-vs2010-40-AnyCpu-Release.zip.lastUpdated

在您的本地存儲庫中。 嘗試刪除它。 它可以阻止Maven重新嘗試下載。