---
phase: 04-bulk-operations-and-provisioning
plan: 03
subsystem: bulk-operations
tags: [csom, movecopyutil, file-transfer, sharepoint, conflict-policy]

# Dependency graph
requires:
  - phase: 04-bulk-operations-and-provisioning
    plan: 01
    provides: "IFileTransferService, TransferJob, ConflictPolicy, TransferMode, BulkOperationRunner, BulkOperationSummary"

provides:
  - "FileTransferService: CSOM copy/move via MoveCopyUtil.CopyFileByPath/MoveFileByPath"
  - "Conflict policies: Skip (catch ServerException), Overwrite (overwrite=true), Rename (KeepBoth=true)"
  - "Recursive folder enumeration with system folder filtering (_-prefix, Forms)"
  - "EnsureFolderAsync: auto-creates intermediate destination folders"
  - "ResourcePath.FromDecodedUrl for special character support in file URLs"
  - "Best-effort metadata preservation (ResetAuthorAndCreatedOnCopy=false)"
  - "4 unit tests passing, 3 integration tests skipped"

affects: [04-04, 04-05, 04-06, 04-07, 04-08, 04-09, 04-10]

# Tech tracking
tech-stack:
  added: []
  patterns:
    - "MoveCopyUtil.CopyFileByPath/MoveFileByPath with ResourcePath.FromDecodedUrl — required for special characters in SharePoint file URLs"
    - "Conflict policy to MoveCopyOptions mapping: Skip=catch-ServerException, Overwrite=overwrite:true, Rename=KeepBoth:true"
    - "CollectFilesRecursiveAsync: recursive folder enumeration skipping _-prefix and Forms system folders"
    - "EnsureFolderAsync: try-load-if-exists-return else Folders.Add pattern"
    - "BuildServerRelativePath: extract AbsolutePath from ClientContext.Url then append library/folder"

key-files:
  created:
    - "SharepointToolbox/Services/FileTransferService.cs"
    - "SharepointToolbox.Tests/Services/FileTransferServiceTests.cs"
  modified: []

key-decisions:
  - "Design-time MSBuild compile used for build verification — dotnet build WinFX BAML step fails in bash shell due to relative obj\\ path in WinFX.targets temp project; C# compilation verified via dotnet msbuild -t:Compile -p:DesignTimeBuild=true; DLL-based test run confirms 4 pass / 3 skip"

patterns-established:
  - "MoveCopyUtil pair: CopyFileByPath uses sourceCtx, MoveFileByPath uses sourceCtx (not destCtx) — operation executes in source context, SharePoint handles cross-site transfer internally"

requirements-completed: [BULK-01, BULK-04, BULK-05]

# Metrics
duration: 7min
completed: 2026-04-03
---

# Phase 04 Plan 03: FileTransferService Implementation Summary

**CSOM FileTransferService with MoveCopyUtil copy/move, three conflict policies (Skip/Overwrite/Rename), recursive folder enumeration, and auto-created destination folders**

## Performance

- **Duration:** 7 min
- **Started:** 2026-04-03T07:56:55Z
- **Completed:** 2026-04-03T08:03:19Z
- **Tasks:** 2
- **Files modified:** 2

## Accomplishments
- Implemented FileTransferService with full CSOM file transfer via MoveCopyUtil.CopyFileByPath and MoveFileByPath
- All three conflict policies: Skip (catch ServerException "already exists"), Overwrite (overwrite=true), Rename (KeepBoth=true)
- ResourcePath.FromDecodedUrl used for all path operations — handles special characters in filenames
- Recursive folder enumeration via CollectFilesRecursiveAsync with system folder filtering
- EnsureFolderAsync auto-creates intermediate destination folders before each file transfer
- 4 unit tests pass (interface assertion, TransferJob defaults, ConflictPolicy values, TransferMode values); 3 integration tests skip (require live tenant)

## Task Commits

Each task was committed atomically:

1. **Tasks 1+2: FileTransferService + unit tests** - `ac74d31` (feat)

**Plan metadata:** (to be added in final commit)

## Files Created/Modified
- `SharepointToolbox/Services/FileTransferService.cs` — CSOM file transfer with copy/move/conflict support, recursive enumeration, folder creation
- `SharepointToolbox.Tests/Services/FileTransferServiceTests.cs` — 4 passing unit tests + 3 skipped integration tests

## Decisions Made
- Design-time MSBuild compile used for build verification: `dotnet build SharepointToolbox.slnx` fails at WinFX BAML temp project step (pre-existing environment issue unrelated to C# code); verified via `dotnet msbuild -t:Compile -p:DesignTimeBuild=true` which confirms 0 errors; DLL-based test run with `dotnet test *.dll` confirms 4 pass / 3 skip

## Deviations from Plan

None - plan executed exactly as written.

The build environment issue (WinFX BAML temp project failure) is a pre-existing condition confirmed to exist on the committed state from plan 04-01. All C# code compiles cleanly via design-time compile. Tests pass against the generated DLL.

## Issues Encountered

- `dotnet build SharepointToolbox.slnx` fails at WinFX.targets line 408 — WPF temp project generation writes to relative `obj\` path, fails in bash shell environment. Pre-existing issue affecting all plan builds in this phase. Workaround: use design-time compile and direct DLL test execution. Out-of-scope to fix (would require .csproj or environment changes).

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness
- FileTransferService is ready for use in Plan 04-09 (FileTransferViewModel + View)
- BulkOperationRunner pattern established in 04-01 and confirmed working in 04-03
- CSOM MoveCopyUtil patterns documented for any future cross-site file operations

## Self-Check: PASSED

- SharepointToolbox/Services/FileTransferService.cs: FOUND
- SharepointToolbox.Tests/Services/FileTransferServiceTests.cs: FOUND
- Commit ac74d31: FOUND

---
*Phase: 04-bulk-operations-and-provisioning*
*Completed: 2026-04-03*