Skip to content

[MRESOLVER-633] Document caching of unresolvable artifacts #651

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Feb 10, 2025
Merged

[MRESOLVER-633] Document caching of unresolvable artifacts #651

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 18 additions & 0 deletions src/site/markdown/local-repository.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -18,6 +18,8 @@ specific language governing permissions and limitations
under the License.
-->

<!--MACRO{toc|fromDepth=1}-->

Maven Resolver implements a "local repository" (that is used by Maven itself
as well), that since the beginning of time was a "mixed bag of beans",
it served twofold purposes: to cache the artifacts downloaded from
Expand Down Expand Up @@ -188,3 +190,19 @@ available, providing out of the box lock implementations for cases like:

For details see [Named Locks module](maven-resolver-named-locks/).

## Error Handling and Caching

By default each artifact which cannot be resolved leads to an error either classified as

1. *not found* error or
2. (any) *other* error (for authentication issues, timeouts etc.)

The caching behavior for both types can be be configured programmatically via `org.eclipse.aether.DefaultRepositorySystemSession.setResolutionErrorPolicy(...)`.

In case caching is enabled for any of the two classifications a Java Properties file is created/updated (with the same filename as the cached artifact in the success case would get but with the additional suffix `.lastUpdated`) in the local repository. Within that file the key `<canonical-remote-url>.error` is updated/added. Its value either contains the error message (for type 2 resolver errors) or is empty (for type 1 resolver errors).

### Configuration in Maven

In Maven 3 resolver errors of **type 1** are **always cached** and the ones of **type 2** are **never cached**.

With [Maven 4](https://issues.apache.org/jira/browse/MNG-7653) the caching of type 1 errors can be disabled with CLI option `-canf false` (still enabled by default). However, the caching of type 2 errors is disabled without any way to override that policy even in Maven 4.