Two new extension points for third-party attachment/cloud-storage plugins
(e.g. a WebDAV/Nextcloud file browser), neither of which the plugin API
currently supports:
- attachment-actions: a new slot rendered into every attachment's hover
action row (all six render paths: beside-sender/below-header/mobile,
each in its compact and expanded-popup form), with the AttachmentInfo
(name, type, size, blobId, emailId) passed through extraProps. Lets a
plugin offer a 'save this attachment elsewhere' action next to the
existing download/preview buttons - previously the only per-attachment
hook was the read-only onAttachmentDownload observer.
- composer-attachment-source: a new slot rendered in the composer toolbar
next to the existing composer-toolbar slot, with an onAttach(upload)
callback in extraProps. Lets a plugin that has already uploaded a file to
the JMAP server itself (api.jmap.uploadBlob) - e.g. a file picked from an
external cloud storage browser - have it added to the current draft as a
real attachment. Previously there was no way for a plugin to add an
attachment to the draft at all; the closest existing mechanism
(onBeforeBlobUpload's ExternalAttachmentResult) only replaces a locally
picked file with body text/a link, it cannot add a brand-new attachment
from an external source.
Both slots follow the existing PluginSlot pattern (calendar-event-actions):
render nothing when no plugin offers the slot, so this is purely additive.
Motivating use case: the existing nextcloud-attachments community plugin
uploads local files to Nextcloud and appends a share link to the message
body - useful for large files, but there was no way for a plugin to do the
inverse (attach a file that already lives in cloud storage as a real binary
attachment, not a link) or to let attachment recipients save an incoming
attachment back out to their own cloud storage. These two slots make both
directions possible without touching plugin-store or the sandbox bridge -
existing slot/extraProps plumbing (see calendar-event-actions) already
supports arbitrary POJO props.
bartfaizoli76
06f51486e0