feat: abstract pre-signed upload request creation

[alvarosanchez]

Summary

• add a portable presigned upload request API in object-storage-core
• implement provider-backed signed PUT request generation for AWS, GCP, and Azure
• document the new pre-signed upload flow and add controller-facing doc examples

Why

Micronaut Object Storage already abstracts direct upload/download operations, but it did not expose a first-class way to generate time-limited client upload requests. Some providers require signed headers in addition to the URL, so the API needs to return the full request shape instead of only a link.

Closes #631.

Validation

• ./gradlew --no-daemon :micronaut-doc-examples:micronaut-example-java:compileJava :micronaut-doc-examples:micronaut-example-groovy:compileGroovy :micronaut-doc-examples:micronaut-example-kotlin:compileKotlin :micronaut-object-storage-core:test --tests 'io.micronaut.objectstorage.ObjectStorageOperationsPresignedUploadFallbackSpec' :micronaut-object-storage-aws:test --tests 'io.micronaut.objectstorage.aws.AwsS3PresignedUploadSpec' :micronaut-object-storage-gcp:test --tests 'io.micronaut.objectstorage.googlecloud.GoogleCloudStoragePresignedUploadSpec' :micronaut-object-storage-azure:test --tests 'io.micronaut.objectstorage.azure.AzureBlobStoragePresignedUploadSpec' japiCmp docs

[Copilot]

Pull request overview

This PR introduces a new portable API in object-storage-core for generating time-limited, client-replayable pre-signed upload HTTP requests, with provider-specific implementations for AWS S3, Google Cloud Storage, and Azure Blob Storage, plus corresponding documentation and doc-example controllers.

Changes:

• Adds CreatePresignedUploadRequest + PresignedUpload types and a default ObjectStorageOperations#createPresignedUpload(...) API returning Optional.
• Implements provider-backed signed PUT request generation for AWS, GCP, and Azure, with new provider-specific tests.
• Adds a dedicated “Pre-Signed Uploads” documentation section and Java/Groovy/Kotlin controller examples.

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/main/docs/guide/toc.yml	Adds the new “Pre-Signed Uploads” section to the guide navigation.
src/main/docs/guide/quickStart.adoc	Links quick start readers to the new pre-signed uploads section.
src/main/docs/guide/preSignedUploads.adoc	Documents the new pre-signed upload flow and provides a controller example snippet.
object-storage-core/src/main/java/io/micronaut/objectstorage/ObjectStorageOperations.java	Adds the portable createPresignedUpload default method returning Optional.
object-storage-core/src/main/java/io/micronaut/objectstorage/request/CreatePresignedUploadRequest.java	Defines request parameters for creating a pre-signed upload (key, expiry, optional headers/metadata).
object-storage-core/src/main/java/io/micronaut/objectstorage/response/PresignedUpload.java	Defines the portable “full request shape” response (URI/method/headers/expiration).
object-storage-core/src/test/groovy/io/micronaut/objectstorage/ObjectStorageOperationsPresignedUploadFallbackSpec.groovy	Verifies the default interface method behavior (providers not overriding return empty).
object-storage-aws/src/main/java/io/micronaut/objectstorage/aws/AwsS3Operations.java	Implements AWS S3 pre-signed PUT creation via S3Presigner.
object-storage-aws/src/test/groovy/io/micronaut/objectstorage/aws/AwsS3PresignedUploadSpec.groovy	Adds AWS presigned upload unit tests.
object-storage-gcp/src/main/java/io/micronaut/objectstorage/googlecloud/GoogleCloudStorageOperations.java	Implements GCS signed PUT generation via Storage#signUrl(...) with portable headers.
object-storage-gcp/src/test/groovy/io/micronaut/objectstorage/googlecloud/GoogleCloudStoragePresignedUploadSpec.groovy	Adds GCP presigned upload unit tests.
object-storage-azure/src/main/java/io/micronaut/objectstorage/azure/AzureBlobStorageOperations.java	Adds Azure SAS-based signed upload generation and returns portable headers.
object-storage-azure/src/test/groovy/io/micronaut/objectstorage/azure/AzureBlobStoragePresignedUploadSpec.groovy	Adds Azure presigned upload unit tests.
object-storage-azure/src/test/groovy/io/micronaut/objectstorage/azure/AzureBlobStoragePaginationSpec.groovy	Updates test subclass constructor call due to Azure operations constructor signature change.
doc-examples/example-java/src/main/java/example/PresignedUploadController.java	Adds Java doc-example controller for returning a presigned upload payload.
doc-examples/example-groovy/src/main/groovy/example/PresignedUploadController.groovy	Adds Groovy doc-example controller for returning a presigned upload payload.
doc-examples/example-kotlin/src/main/kotlin/example/PresignedUploadController.kt	Adds Kotlin doc-example controller for returning a presigned upload payload.

[alvarosanchez]

Addressed the remaining review follow-ups on this branch:

• reject blank CreatePresignedUploadRequest.contentType values
• return Optional.empty() for Azure presigning when shared-key credentials are unavailable
• align the guide contract text with the runtime behavior

Verification:

• ./gradlew --no-daemon :micronaut-object-storage-core:test --tests 'io.micronaut.objectstorage.request.CreatePresignedUploadRequestSpec' --tests 'io.micronaut.objectstorage.ObjectStorageOperationsPresignedUploadFallbackSpec'\n- ./gradlew --no-daemon :micronaut-object-storage-azure:test --tests 'io.micronaut.objectstorage.azure.AzureBlobStoragePresignedUploadSpec'\n- ./gradlew --no-daemon japiCmp docs

[sonarqubecloud]

Quality Gate passed

Issues
4 New issues
0 Accepted issues

Measures
0 Security Hotspots
90.4% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud