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GOPEED BACKEND IMPLEMENTATION & VERIFICATION TEST REPORT
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Date: 2026-09-22
Repository: https://github.com/GopeedLab/gopeed
Scope: Backend Only (Go 1.26.5 / Windows x86_64)
Status: ALL TESTS PASSED - NO REGRESSIONS

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1. OVERVIEW OF IMPLEMENTATION & CHANGES
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Milestone 1: HTTP Download Checksum Verification
- Added `ChecksumOption` struct (Algorithm: md5/sha1/sha256, Expected: hex string) in pkg/base/model.go.
- Added optional `Checksum *ChecksumOption` (`json:"checksum,omitempty"`) to `base.Options`.
- Implemented streaming file checksum verification in `internal/protocol/http/fetcher.go` via `verifyChecksum()`.
  Zero memory overhead (streams directly from file on disk via 64KB buffer).
- Wired checksum verification into the completion pathways of HTTP fetcher. Fails gracefully with descriptive mismatch error if hash does not match, marking task as failed.
- Wired optional checksum fields into MCP `downloadOptions` and `pkg/rest/model/task.go`.

Milestone 2: New MCP Tool (get_download_speed)
- Implemented `get_download_speed` tool in `pkg/mcpserver/server.go`.
- Supports querying instantaneous download/upload speed, total/downloaded bytes, progress percentage, and ETA calculation for:
  a) A specific task ID.
  b) Global aggregate speed across all active running tasks when task ID is omitted.
- Registered in MCP tool registry with read-only annotations.

Milestone 3: Webhook Lifecycle Enhancements
- Added `WebhookEventDownloadPause` ("DOWNLOAD_PAUSE") event type in `pkg/download/webhook.go`.
- Triggered `DOWNLOAD_PAUSE` event on task pause in `pkg/download/downloader.go`.

Milestone 4: CLI Parity
- Added `-checksum` and `-checksum-algo` (default: md5) flags to `cmd/gopeed/flags.go`.
- Configured `cmd/gopeed/main.go` to construct `ChecksumOption` and pass it to download tasks.

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2. TEST EXECUTION SUMMARY
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Package: github.com/GopeedLab/gopeed/internal/protocol/http
- TestFetcher_ChecksumVerification/Valid_MD5: PASSED
- TestFetcher_ChecksumVerification/Valid_SHA256: PASSED
- TestFetcher_ChecksumVerification/Wrong_MD5_mismatch: PASSED (Proper error returned)
- TestFetcher_ChecksumVerification/Unsupported_Algorithm: PASSED (Proper error returned)
- TestFetcher_ChecksumVerification/No_Checksum_(Opt-in_backward_compatibility): PASSED
Result: PASS (All 5/5 subtests passed)

Package: github.com/GopeedLab/gopeed/pkg/mcpserver
- TestStreamableHTTPTools: PASSED (All 10 tools verified including get_download_speed)
- TestStreamableHTTPRejectsCrossOriginRequest: PASSED
- TestGetDownloadSpeedTool: PASSED (Global speed & task not found error cases verified)
Result: PASS (3/3 tests passed)

Package: github.com/GopeedLab/gopeed/pkg/download
- TestWebhook_TriggerOnPause: PASSED (Verified DOWNLOAD_PAUSE webhook event reception)
- TestWebhook_TriggerOnDone: PASSED
- TestWebhook_TriggerOnError: PASSED
- TestWebhook_SendTestWebhook: PASSED
Result: PASS

Package: github.com/GopeedLab/gopeed/pkg/base
- TestDownloaderStoreConfig_Init: PASSED
- TestDownloaderStoreConfig_Merge: PASSED
- TestPieceMapCRUDAndBytes: PASSED
- TestPieceMapValidationAndRestore: PASSED
- TestPieceMapJSON: PASSED
- TestPieceMapCloneIsIndependent: PASSED
Result: PASS

Package: github.com/GopeedLab/gopeed/pkg/rest
- TestNativeInvokeWithoutRESTListener: PASSED
- TestStartAPIServerIsNotBlockedByPendingDispatch: PASSED
- TestAPIServerLifecycleUsesPersistedConfigWithoutRestartingCore: PASSED
- TestRestartAPIServerFailsFastAndLeavesListenerStopped: PASSED
- TestNativeRESTSettingPersistsInGoStorage: PASSED
- TestNativeAPIServerAutoStartFailureKeepsCoreAvailable: PASSED
- TestInfo: PASSED
- TestResolve: PASSED
- TestCreateTask: PASSED
- TestCreateResolvedTaskUsesSubmittedOptions: PASSED
- TestCreateDirectTask: PASSED
- TestGetTaskStatus: PASSED
- TestCreateDirectTaskBatch: PASSED
- TestCreateDirectTaskBatchWithOpt: PASSED
- TestPauseAndContinueTask: PASSED
- TestPatchTask: PASSED
- TestPatchTaskNotFound: PASSED
- TestPauseAllAndContinueALLTasks: PASSED
- TestDeleteTask: PASSED
- TestDeleteTaskForce: PASSED
- TestDeleteAllTasks: PASSED
- TestDeleteTasksByStatues: PASSED
- TestGetTasks: PASSED
- TestGetAndPutConfig: PASSED
- TestInstallExtension: PASSED
- TestGetExtensions: PASSED
- TestUpdateExtensionSettings: PASSED
- TestSwitchExtension: PASSED
- TestDeleteExtension: PASSED
- TestUpdateCheckExtension: PASSED
- TestFsExtension: PASSED
- TestFsExtensionFail: PASSED
- TestWebFsEnhance: PASSED
- TestDoProxy: PASSED
- TestTestWebhook: PASSED
- TestApiToken: PASSED
- TestMCPRouteToggle: PASSED
- TestBuildServerRejectsWebAPITokenWithoutWebAuth: PASSED
- TestAuthorization: PASSED
- TestWebSessionStoreExpiry: PASSED
- TestBuildServerPropagatesWebViewProvider: PASSED
Result: PASS

Build Verification:
- cmd/api: Compiled successfully (0 errors)
- cmd/gopeed: Compiled successfully (0 errors)

Lint & Code Style:
- gofmt: Clean (all modified files formatted according to Go standards)
- go vet: Clean (0 warnings, 0 errors across all modified packages)

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3. BACKWARD COMPATIBILITY & UI INTEGRITY CONFIRMATION
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- Zero changes to Flutter/UI codebase.
- All new options are purely opt-in (tagged with `omitempty` in JSON / nil-safe checks in Go).
- Existing API contracts, REST requests, and MCP tool workflows continue to function without any breaking alterations.

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END OF REPORT
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