An in browser local PDS
localpds.at
Inital backend
authored by
Niall Bunting
and committed by
Niall Bunting
(May 29, 2026, 9:00 AM +0100)
fa6fe474
fc48d301
+310
backend/backend-linux
backend/backend-linux
This is a binary file and will not be displayed.
+189
backend/backend.go
+189
backend/backend.go
···
1
+
package main
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+
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+
import (
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+
"encoding/base64"
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+
"encoding/json"
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+
"log"
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+
"net/http"
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"strings"
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"sync"
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"time"
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+
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"github.com/gin-gonic/gin"
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"github.com/google/uuid"
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"github.com/gorilla/websocket"
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)
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const SecretKey = "your-shared-secret-key"
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// Base WS Message payload structure
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type WSMessage struct {
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Secret string `json:"secret,omitempty"`
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Type string `json:"type"`
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PeerID string `json:"peerId,omitempty"`
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Target string `json:"target,omitempty"`
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Sender string `json:"sender,omitempty"`
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RequestID string `json:"requestId,omitempty"`
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URL string `json:"url,omitempty"`
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Signal json.RawMessage `json:"signal,omitempty"`
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CarBytes string `json:"carBytes,omitempty"`
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Error string `json:"error,omitempty"`
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}
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// Thread-safe registry for connected extensions and pending HTTP requests
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type Registry struct {
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mu sync.RWMutex
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peers map[string]*websocket.Conn
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pendingSyncs map[string]chan []byte
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}
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var registry = &Registry{
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peers: make(map[string]*websocket.Conn),
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pendingSyncs: make(map[string]chan []byte),
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}
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var upgrader = websocket.Upgrader{
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CheckOrigin: func(r *http.Request) bool {
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return true // Allow extensions to connect from chrome-extension:// origins
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},
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}
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func main() {
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r := gin.Default()
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// 1. Signaling & P2P Coordination WebSocket Endpoint
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r.GET("/ws/sync", func(c *gin.Context) {
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conn, err := upgrader.Upgrade(c.Writer, c.Request, nil)
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if err != nil {
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log.Printf("Upgrade error: %v", err)
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return
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}
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defer conn.Close()
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var currentPeerID string
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defer func() {
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if currentPeerID != "" {
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registry.mu.Lock()
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delete(registry.peers, currentPeerID)
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registry.mu.Unlock()
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log.Printf("Peer disconnected: %s", currentPeerID)
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}
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}()
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for {
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_, msgBytes, err := conn.ReadMessage()
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if err != nil {
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break
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}
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var msg WSMessage
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if err := json.Unmarshal(msgBytes, &msg); err != nil {
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continue
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}
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// All signaling operations require the shared secret guardrail
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if msg.Secret != SecretKey {
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conn.WriteJSON(WSMessage{Type: "error", Error: "Unauthorized"})
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return // close connection
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}
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switch msg.Type {
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case "register":
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currentPeerID = msg.PeerID
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registry.mu.Lock()
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registry.peers[currentPeerID] = conn
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registry.mu.Unlock()
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log.Printf("Peer registered: %s", currentPeerID)
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case "signal":
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// Extension routes WebRTC SDP/ICE signaling to another peer
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registry.mu.RLock()
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targetConn, exists := registry.peers[msg.Target]
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registry.mu.RUnlock()
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if exists {
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targetConn.WriteJSON(WSMessage{
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Type: "signal",
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Sender: currentPeerID,
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Signal: msg.Signal,
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})
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}
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case "relay-response-data":
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// Extension returns raw CAR data requested by the XRPC proxy
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registry.mu.Lock()
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resChan, exists := registry.pendingSyncs[msg.RequestID]
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if exists {
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rawBytes, err := base64.StdEncoding.DecodeString(msg.CarBytes)
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+
if err == nil {
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resChan <- rawBytes
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+
}
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delete(registry.pendingSyncs, msg.RequestID)
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+
}
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registry.mu.Unlock()
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+
}
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}
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+
})
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// 2. Bluesky XRPC Relay Sync Proxy Endpoint
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r.GET("/xrpc/:method", func(c *gin.Context) {
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method := c.Param("method")
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// Ensure we are only intercepting the sync methods we care about
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if !strings.HasPrefix(method, "com.atproto.sync.") {
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c.JSON(http.StatusNotFound, gin.H{"error": "MethodNotImplemented", "message": "Only sync methods are handled here"})
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+
return
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+
}
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registry.mu.RLock()
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peerConn, online := registry.peers[did]
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registry.mu.RUnlock()
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+
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if !online {
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c.JSON(http.StatusNotFound, gin.H{"error": "RepoNotFound", "message": "Peer extension is not online"})
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+
return
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+
}
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+
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reqID := uuid.New().String()
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responseChan := make(chan []byte, 1)
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registry.mu.Lock()
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registry.pendingSyncs[reqID] = responseChan
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registry.mu.Unlock()
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// Request the extension to compile the data for this specific route
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err := peerConn.WriteJSON(WSMessage{
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Type: "relay-request",
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RequestID: reqID,
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URL: c.Request.URL.String(), // Preserves the full /xrpc/com.atproto.sync.getRepo?did=...
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+
})
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+
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if err != nil {
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registry.mu.Lock()
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delete(registry.pendingSyncs, reqID)
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registry.mu.Unlock()
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c.JSON(http.StatusInternalServerError, gin.H{"error": "InternalError", "message": "Failed to poll extension"})
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return
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+
}
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+
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+
// Block and wait for the extension to respond via WebSocket, or timeout
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+
select {
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+
case carBytes := <-responseChan:
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c.Header("Content-Type", "application/vnd.ipld.car")
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c.Header("Atproto-Repo-Rev", "optional-tid-placeholder")
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c.Data(http.StatusOK, "application/vnd.ipld.car", carBytes)
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+
case <-time.After(15 * time.Second):
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registry.mu.Lock()
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delete(registry.pendingSyncs, reqID)
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registry.mu.Unlock()
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c.JSON(http.StatusGatewayTimeout, gin.H{"error": "UpstreamTimeout", "message": "Extension failed to stream CAR blocks in time"})
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}
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})
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log.Println("Server running on :3030")
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+
if err := r.Run(":3000"); err != nil {
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+
log.Fatalf("Server failed to start: %v", err)
188
+
}
189
+
}
+38
backend/go.mod
+38
backend/go.mod
···
1
+
module bsky-p2p-sync
2
+
3
+
go 1.25.0
4
+
5
+
require (
6
+
github.com/bytedance/gopkg v0.1.3 // indirect
7
+
github.com/bytedance/sonic v1.15.0 // indirect
8
+
github.com/bytedance/sonic/loader v0.5.0 // indirect
9
+
github.com/cloudwego/base64x v0.1.6 // indirect
10
+
github.com/gabriel-vasile/mimetype v1.4.12 // indirect
11
+
github.com/gin-contrib/sse v1.1.0 // indirect
12
+
github.com/gin-gonic/gin v1.12.0 // indirect
13
+
github.com/go-playground/locales v0.14.1 // indirect
14
+
github.com/go-playground/universal-translator v0.18.1 // indirect
15
+
github.com/go-playground/validator/v10 v10.30.1 // indirect
16
+
github.com/goccy/go-json v0.10.5 // indirect
17
+
github.com/goccy/go-yaml v1.19.2 // indirect
18
+
github.com/google/uuid v1.6.0 // indirect
19
+
github.com/gorilla/websocket v1.5.3 // indirect
20
+
github.com/json-iterator/go v1.1.12 // indirect
21
+
github.com/klauspost/cpuid/v2 v2.3.0 // indirect
22
+
github.com/leodido/go-urn v1.4.0 // indirect
23
+
github.com/mattn/go-isatty v0.0.20 // indirect
24
+
github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
25
+
github.com/modern-go/reflect2 v1.0.2 // indirect
26
+
github.com/pelletier/go-toml/v2 v2.2.4 // indirect
27
+
github.com/quic-go/qpack v0.6.0 // indirect
28
+
github.com/quic-go/quic-go v0.59.0 // indirect
29
+
github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
30
+
github.com/ugorji/go/codec v1.3.1 // indirect
31
+
go.mongodb.org/mongo-driver/v2 v2.5.0 // indirect
32
+
golang.org/x/arch v0.22.0 // indirect
33
+
golang.org/x/crypto v0.48.0 // indirect
34
+
golang.org/x/net v0.51.0 // indirect
35
+
golang.org/x/sys v0.41.0 // indirect
36
+
golang.org/x/text v0.34.0 // indirect
37
+
google.golang.org/protobuf v1.36.10 // indirect
38
+
)
+82
backend/go.sum
+82
backend/go.sum
···
1
+
github.com/bytedance/gopkg v0.1.3 h1:TPBSwH8RsouGCBcMBktLt1AymVo2TVsBVCY4b6TnZ/M=
2
+
github.com/bytedance/gopkg v0.1.3/go.mod h1:576VvJ+eJgyCzdjS+c4+77QF3p7ubbtiKARP3TxducM=
3
+
github.com/bytedance/sonic v1.15.0 h1:/PXeWFaR5ElNcVE84U0dOHjiMHQOwNIx3K4ymzh/uSE=
4
+
github.com/bytedance/sonic v1.15.0/go.mod h1:tFkWrPz0/CUCLEF4ri4UkHekCIcdnkqXw9VduqpJh0k=
5
+
github.com/bytedance/sonic/loader v0.5.0 h1:gXH3KVnatgY7loH5/TkeVyXPfESoqSBSBEiDd5VjlgE=
6
+
github.com/bytedance/sonic/loader v0.5.0/go.mod h1:AR4NYCk5DdzZizZ5djGqQ92eEhCCcdf5x77udYiSJRo=
7
+
github.com/cloudwego/base64x v0.1.6 h1:t11wG9AECkCDk5fMSoxmufanudBtJ+/HemLstXDLI2M=
8
+
github.com/cloudwego/base64x v0.1.6/go.mod h1:OFcloc187FXDaYHvrNIjxSe8ncn0OOM8gEHfghB2IPU=
9
+
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
10
+
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
11
+
github.com/gabriel-vasile/mimetype v1.4.12 h1:e9hWvmLYvtp846tLHam2o++qitpguFiYCKbn0w9jyqw=
12
+
github.com/gabriel-vasile/mimetype v1.4.12/go.mod h1:d+9Oxyo1wTzWdyVUPMmXFvp4F9tea18J8ufA774AB3s=
13
+
github.com/gin-contrib/sse v1.1.0 h1:n0w2GMuUpWDVp7qSpvze6fAu9iRxJY4Hmj6AmBOU05w=
14
+
github.com/gin-contrib/sse v1.1.0/go.mod h1:hxRZ5gVpWMT7Z0B0gSNYqqsSCNIJMjzvm6fqCz9vjwM=
15
+
github.com/gin-gonic/gin v1.12.0 h1:b3YAbrZtnf8N//yjKeU2+MQsh2mY5htkZidOM7O0wG8=
16
+
github.com/gin-gonic/gin v1.12.0/go.mod h1:VxccKfsSllpKshkBWgVgRniFFAzFb9csfngsqANjnLc=
17
+
github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/oXslEjJA=
18
+
github.com/go-playground/locales v0.14.1/go.mod h1:hxrqLVvrK65+Rwrd5Fc6F2O76J/NuW9t0sjnWqG1slY=
19
+
github.com/go-playground/universal-translator v0.18.1 h1:Bcnm0ZwsGyWbCzImXv+pAJnYK9S473LQFuzCbDbfSFY=
20
+
github.com/go-playground/universal-translator v0.18.1/go.mod h1:xekY+UJKNuX9WP91TpwSH2VMlDf28Uj24BCp08ZFTUY=
21
+
github.com/go-playground/validator/v10 v10.30.1 h1:f3zDSN/zOma+w6+1Wswgd9fLkdwy06ntQJp0BBvFG0w=
22
+
github.com/go-playground/validator/v10 v10.30.1/go.mod h1:oSuBIQzuJxL//3MelwSLD5hc2Tu889bF0Idm9Dg26cM=
23
+
github.com/goccy/go-json v0.10.5 h1:Fq85nIqj+gXn/S5ahsiTlK3TmC85qgirsdTP/+DeaC4=
24
+
github.com/goccy/go-json v0.10.5/go.mod h1:oq7eo15ShAhp70Anwd5lgX2pLfOS3QCiwU/PULtXL6M=
25
+
github.com/goccy/go-yaml v1.19.2 h1:PmFC1S6h8ljIz6gMRBopkjP1TVT7xuwrButHID66PoM=
26
+
github.com/goccy/go-yaml v1.19.2/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
27
+
github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
28
+
github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
29
+
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
30
+
github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
31
+
github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
32
+
github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
33
+
github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
34
+
github.com/klauspost/cpuid/v2 v2.3.0 h1:S4CRMLnYUhGeDFDqkGriYKdfoFlDnMtqTiI/sFzhA9Y=
35
+
github.com/klauspost/cpuid/v2 v2.3.0/go.mod h1:hqwkgyIinND0mEev00jJYCxPNVRVXFQeu1XKlok6oO0=
36
+
github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
37
+
github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
38
+
github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
39
+
github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
40
+
github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
41
+
github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
42
+
github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
43
+
github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
44
+
github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
45
+
github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
46
+
github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
47
+
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
48
+
github.com/quic-go/qpack v0.6.0 h1:g7W+BMYynC1LbYLSqRt8PBg5Tgwxn214ZZR34VIOjz8=
49
+
github.com/quic-go/qpack v0.6.0/go.mod h1:lUpLKChi8njB4ty2bFLX2x4gzDqXwUpaO1DP9qMDZII=
50
+
github.com/quic-go/quic-go v0.59.0 h1:OLJkp1Mlm/aS7dpKgTc6cnpynnD2Xg7C1pwL6vy/SAw=
51
+
github.com/quic-go/quic-go v0.59.0/go.mod h1:upnsH4Ju1YkqpLXC305eW3yDZ4NfnNbmQRCMWS58IKU=
52
+
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
53
+
github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
54
+
github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
55
+
github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
56
+
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
57
+
github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
58
+
github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
59
+
github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
60
+
github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
61
+
github.com/twitchyliquid64/golang-asm v0.15.1 h1:SU5vSMR7hnwNxj24w34ZyCi/FmDZTkS4MhqMhdFk5YI=
62
+
github.com/twitchyliquid64/golang-asm v0.15.1/go.mod h1:a1lVb/DtPvCB8fslRZhAngC2+aY1QWCk3Cedj/Gdt08=
63
+
github.com/ugorji/go/codec v1.3.1 h1:waO7eEiFDwidsBN6agj1vJQ4AG7lh2yqXyOXqhgQuyY=
64
+
github.com/ugorji/go/codec v1.3.1/go.mod h1:pRBVtBSKl77K30Bv8R2P+cLSGaTtex6fsA2Wjqmfxj4=
65
+
go.mongodb.org/mongo-driver/v2 v2.5.0 h1:yXUhImUjjAInNcpTcAlPHiT7bIXhshCTL3jVBkF3xaE=
66
+
go.mongodb.org/mongo-driver/v2 v2.5.0/go.mod h1:yOI9kBsufol30iFsl1slpdq1I0eHPzybRWdyYUs8K/0=
67
+
golang.org/x/arch v0.22.0 h1:c/Zle32i5ttqRXjdLyyHZESLD/bB90DCU1g9l/0YBDI=
68
+
golang.org/x/arch v0.22.0/go.mod h1:dNHoOeKiyja7GTvF9NJS1l3Z2yntpQNzgrjh1cU103A=
69
+
golang.org/x/crypto v0.48.0 h1:/VRzVqiRSggnhY7gNRxPauEQ5Drw9haKdM0jqfcCFts=
70
+
golang.org/x/crypto v0.48.0/go.mod h1:r0kV5h3qnFPlQnBSrULhlsRfryS2pmewsg+XfMgkVos=
71
+
golang.org/x/net v0.51.0 h1:94R/GTO7mt3/4wIKpcR5gkGmRLOuE/2hNGeWq/GBIFo=
72
+
golang.org/x/net v0.51.0/go.mod h1:aamm+2QF5ogm02fjy5Bb7CQ0WMt1/WVM7FtyaTLlA9Y=
73
+
golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
74
+
golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
75
+
golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
76
+
golang.org/x/text v0.34.0 h1:oL/Qq0Kdaqxa1KbNeMKwQq0reLCCaFtqu2eNuSeNHbk=
77
+
golang.org/x/text v0.34.0/go.mod h1:homfLqTYRFyVYemLBFl5GgL/DWEiH5wcsQ5gSh1yziA=
78
+
google.golang.org/protobuf v1.36.10 h1:AYd7cD/uASjIL6Q9LiTjz8JLcrh/88q5UObnmY3aOOE=
79
+
google.golang.org/protobuf v1.36.10/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
80
+
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
81
+
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
82
+
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+1
backend/makefile
+1
backend/makefile
···
1
+
GOOS=linux GOARCH=amd64 go build -ldflags="-s -w" -o backend-linux main.go