DavKit
Open Office documents from your Java web app and save them straight back.
DavKit is a commercial Java WebDAV toolkit for Spring Boot and Grails. Your users click an edit link, the document opens in desktop Word, Excel or PowerPoint, and Save writes it straight back into your application. No download, no re-upload, no desktop helper to install.
DavKit supplies the WebDAV engine, locking, authentication strategies and browser bridge that let Microsoft Office open and save documents held in a Java web application built on Spring Boot or Grails, under one licence.
- Users keep full desktop Office instead of a cut-down browser editor
- Documents stay in your application, one authoritative version
- Spring Boot 3 and 4; dedicated Grails 7 plugin
- Save-back proven with real Word, Excel and PowerPoint sessions on Windows and Mac
The download–edit–upload loop is where documents go wrong
Your application stores the document, but editing it means downloading a copy, opening it in Office and uploading the result. The upload step is where it goes wrong: someone edits yesterday’s copy, or the file does the rounds by email and never comes back, and the version your application holds quietly stops being the real one. In-browser editors avoid the round trip, but they hand your users a limited editor and a different rendering engine in place of the Office they know.
WebDAV is the protocol Word, Excel and PowerPoint already speak; it is the mechanism behind “Open in app” on SharePoint. DavKit gives your own application that capability directly, without involving SharePoint or any Microsoft server, and without moving documents out of your database.
How DavKit opens and saves a document
- Your application renders an
ms-word:,ms-excel:orms-powerpoint:edit link containing an HTTPS DavKit URL. - The desktop application authenticates independently of the browser, using a signed URL, MS-OFBA or Basic over HTTPS. This matters because the desktop editor is a separate client: browser cookies and single-page-application sessions do not travel with the document URL. It is the step where do-it-yourself attempts usually fail.
- DavKit handles discovery, WebDAV Class 2 locking, reads and conditional requests.
- Save streams back through your
DavResourceProvider; metadata and ETags update for the next read.
What changes for your users
The Office they already use
Full desktop Word, Excel and PowerPoint, with track changes, comments, formulas and formatting behaving exactly as your users expect. Nobody has to learn a cut-down editor.
One document, one version
Saves land straight back in the application, so copies stop piling up in Downloads folders and email threads. The application record stays authoritative, with the metadata and audit trail that insurance, legal and public-sector teams expect.
Nothing to install
The edit-link flow uses what Office already ships, so there is nothing new for IT to approve and deploy.
See a complete edit and save-back
Spring Boot WebDAV without a second application stack
DavKit runs inside your existing application rather than as a separate document server or sidecar process. Three lines wire it in:
implementation("com.tucanoo.davkit:server-spring-boot:1.0.0")
davkit.license-key=${DAVKIT_LICENSE_KEY}
@Bean DavResourceProvider documents(DocumentStore store) { return new DatabaseDocuments(store); }DatabaseDocuments is your storage adapter: it implements resolve, read and write against your application’s existing document model, whatever that is. The protocol handling, locking, authentication and Office behaviour stay inside DavKit.
One toolkit for the complete Office save-back path
WebDAV engine
Class 1 and Class 2 methods required for desktop Office editing, conditional requests, ranges and streamed document bodies.
Storage SPI
JPA, GORM, JDBC-backed metadata, S3, filesystem or proprietary storage, without forcing a filesystem model on your data.
Authentication
The desktop editor authenticates as a separate client, so the browser session cannot help it. DavKit ships signed URLs, MS-OFBA and Basic over HTTPS. Signed URLs work with Office on Windows and Mac; MS-OFBA is Windows-only and current Microsoft 365 installations may require managed-client policy; Basic is opt-in over HTTPS and current Office builds may block its prompts by default.
Locks for one node or many
An in-memory lock store by default, and JdbcDavLockStore for clustered deployments.
JavaScript bridge included
ESM and IIFE builds covering the Office and LibreOffice URI schemes, included with every licence.
Diagnostics for real Office traffic
Redacted request logging and behaviours captured from real Word sessions, for when a client does something the RFC never mentioned.
Proprietary software. Source can be made available to licensees for security review under the licence terms.
A Grails WebDAV plugin, not a generic servlet recipe
Grails applications get first-class treatment: a taglib for edit links, a GormDavResourceProvider for GORM-backed documents, and automatic wiring through the Spring Boot starter underneath. The plugin is built for Grails 7 upwards.
<davkit:editLink path="documents/${document.name}" />The protocol is standard. Office behaviour is not.
The WebDAV RFCs describe a tidy protocol. Real Office clients add discovery requests before the first byte of the document, SharePoint-style probe calls, lock refreshes on their own schedule, ETag behaviour that differs between platforms, and authentication flows that interact with your security-filter ordering. DavKit handles these as first-class behaviour, down to redacting signed URLs from its own logs, and the patterns were learned from captured traffic of real Word sessions.
The RFCs are the smaller half of the work: what a licence pays for is Class 2 locking, desktop authentication flows and the accumulated handling of real Office behaviour that an in-house build would have to discover and maintain itself.
Straightforward perpetual licensing
How the published packages compare
Vendor-listed US-dollar prices and product pages checked 26 August 2026. Licence scopes differ; this is not a like-for-like benchmark. Check vendors’ current terms before purchasing.
DavKit questions
What is DavKit?
Production server
$2,500
One production server, perpetual use, every feature, 12 months of updates. Development, CI and staging servers are free.
Update renewal
$1,250/year
A further year of updates. Optional: your existing builds keep working without it.
Redistribution / OEM
From $10,000
Per-organisation starting point for shipping DavKit inside your own product; scope and renewal agreed by quote.
Evaluation
Free
The complete product for 30 days, renewable for longer procurement cycles by request.
Licensing is one key file, verified offline inside your server. DavKit makes no outbound calls and gates no features; server counts are contractual. Commercial builds released within your update window stay licensed in perpetuity.
DavKit is a commercial Java WebDAV toolkit from Tucanoo that lets Microsoft Word, Excel and PowerPoint open documents held in a Spring Boot or Grails application and save changes straight back. It supplies the WebDAV engine, locking, authentication strategies and the browser bridge that starts the desktop editor, under one licence.
Can Word save directly back to a Spring Boot application?
| Published package | DavKit | IT Hit WebDAV Server Library for Java | Milton |
|---|---|---|---|
| Licence shape used for price | One production server, all DavKit components | One server/FQDN | Organisation-wide redistribution package |
| Vendor-listed perpetual price | $2,500 | Engine $2,171.95; engine + AJAX bundle $3,669.44 | Redistribution package $12,453.30 |
Yes. Word opens the document over an HTTPS WebDAV URL served by DavKit inside the Spring Boot application, locks it, and on Save streams the new content back through the application’s storage provider. Real Word, Excel and PowerPoint save-back is verified on Windows and Mac, with nothing downloaded or re-uploaded along the way.
Does DavKit support Grails?
Yes. DavKit ships a dedicated Grails plugin with a taglib for edit links and a GORM-backed resource provider. The plugin is built for Grails 7 upwards, already tested with Grails 8.
Which authentication strategies are included?
Every licence includes signed URLs, MS-OFBA and Basic authentication over HTTPS. Signed URLs work with Office on Windows and Mac. MS-OFBA is Windows-only, and current Microsoft 365 installations may require managed-client policy. Basic authentication is opt-in over HTTPS, and current Office builds may block its prompts by default.
Does DavKit phone home?
No. Licence verification is an offline signature check inside your server, and DavKit makes no outbound calls. An invalid, missing or unsuitable key causes DavKit’s endpoints to return 503 with the reason, while the rest of your application boots and runs normally.
What happens when the update period ends?
Your DavKit builds keep working. A licence includes 12 months of updates; when that window ends, every build released inside it remains licensed in perpetuity, and only newer builds require a renewal.
Are development and CI servers charged?
No. Development, CI and staging servers are free. You pay per production server only.
Does every licence include every feature?
Yes. Every valid key, including the free 30-day evaluation key, enables the complete toolkit. There are no feature tiers and no paid add-ons.
Is DavKit open source?
No. DavKit is proprietary, closed-source software. Source can be made available to licensees for security review under the licence terms.
Can we redistribute DavKit inside our product?
Yes, under a redistribution/OEM licence, priced from $10,000 per organisation and agreed by quote. The standard $2,500 licence covers your own production server and does not include redistribution.
Does it work with Office on Mac?
Yes. Word, Excel and PowerPoint save-back is verified on Mac using signed URLs. The one platform difference is authentication: MS-OFBA is Windows-only, so Mac clients authenticate with signed URLs or Basic over HTTPS.
What does a 30-day evaluation include?
The complete product: every feature, both framework integrations and the JavaScript bridge, with a key that expires after 30 days. Evaluations are renewable on request for longer procurement cycles, and the reference Spring Boot and Grails demo applications show the provider patterns.
Why not just let users download and re-upload documents?
Because the copy forks the moment it is downloaded. Someone edits yesterday’s version, or the upload back never happens, and the application’s record stops being the real one. With DavKit the document never leaves the application: Office reads and writes it in place, so version history and the audit trail stay intact.
How does DavKit compare with embedding a browser editor such as OnlyOffice or Collabora?
An embedded browser editor replaces Office with a different editing application running inside the page, which means operating that editor and accepting its rendering of your documents. DavKit takes the opposite approach: your users keep the full desktop Word, Excel and PowerPoint they already know, and your application keeps serving the documents itself.
Why not move the documents into SharePoint or OneDrive?
Moving documents into SharePoint creates a second system of record: your files move out of the application, and the permissions already built into it have to be mirrored and kept in step somewhere else. DavKit lets documents stay where your application already stores and secures them, with the same “Open in app” behaviour served by your own Spring Boot or Grails application.
Prove the save-back path in your own application
An evaluation key enables the complete toolkit for 30 days, and the reference Spring Boot and Grails demo applications show the provider patterns to copy. If Office can reach your server over HTTPS, you can have a document opening in Word the same afternoon.