Add conversions to and from MongoDB driver (#72)

go.mod

@@ -7,13 +7,14 @@ toolchain go1.23.4
 require (
 	github.com/stretchr/testify v1.10.0
 	github.com/xdg-go/scram v1.1.2
+	go.mongodb.org/mongo-driver/v2 v2.0.0
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
 	github.com/xdg-go/stringprep v1.0.4 // indirect
-	golang.org/x/text v0.3.8 // indirect
+	golang.org/x/text v0.20.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,5 +1,7 @@
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
@@ -11,6 +13,8 @@ github.com/xdg-go/scram v1.1.2/go.mod h1:RT/sEzTbU5y00aCK8UOx6R7YryM0iF1N2MOmC3k
 github.com/xdg-go/stringprep v1.0.4 h1:XLI/Ng3O1Atzq0oBs3TWm+5ZVgkq2aqdlvP9JtoZ6c8=
 github.com/xdg-go/stringprep v1.0.4/go.mod h1:mPGuuIYwz7CmR2bT9j4GbQqutWS1zV24gijq1dTyGkM=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+go.mongodb.org/mongo-driver/v2 v2.0.0 h1:Jfd7XpdZa9yk3eY774bO7SWVb30noLSirL9nKTpavhI=
+go.mongodb.org/mongo-driver/v2 v2.0.0/go.mod h1:nSjmNq4JUstE8IRZKTktLgMHM4F1fccL6HGX1yh+8RA=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
@@ -29,8 +33,9 @@ golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuX
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.3.8 h1:nAL+RVCQ9uMn3vJZbV+MRnydTJFPf8qqY42YiA6MrqY=
 golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
+golang.org/x/text v0.20.0 h1:gK/Kv2otX8gz+wn7Rmb3vT96ZwuoxnQlY+HlJVj7Qug=
+golang.org/x/text v0.20.0/go.mod h1:D4IsuqiFMhST5bX19pQ9ikHC2GsaKyk/oF+pn3ducp4=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=

wirebson/bson.go

@@ -43,6 +43,8 @@ package wirebson
 import (
 	"time"
 
+	"go.mongodb.org/mongo-driver/v2/bson"
+
 	"github.com/FerretDB/wire/internal/util/lazyerrors"
 )
 
@@ -111,3 +113,153 @@ func validBSONType(v any) error {
 
 	return nil
 }
+
+// fromDriver converts MongoDB driver value ([bson.D], [bson.A], etc) to wirebson value.
+func fromDriver(v any) (any, error) {
+	switch v := v.(type) {
+	// composite types
+
+	case bson.D:
+		doc := MakeDocument(len(v))
+		for _, e := range v {
+			val, err := fromDriver(e.Value)
+			if err != nil {
+				return nil, lazyerrors.Error(err)
+			}
+
+			if err = doc.Add(e.Key, val); err != nil {
+				return nil, lazyerrors.Error(err)
+			}
+		}
+
+		return doc, nil
+
+	case bson.A:
+		arr := MakeArray(len(v))
+		for _, e := range v {
+			val, err := fromDriver(e)
+			if err != nil {
+				return nil, lazyerrors.Error(err)
+			}
+
+			if err = arr.Add(val); err != nil {
+				return nil, lazyerrors.Error(err)
+			}
+		}
+
+		return arr, nil
+
+	// scalar types (in the same order as in bson package)
+
+	case float64:
+		return v, nil
+	case string:
+		return v, nil
+	case bson.Binary:
+		return Binary{
+			Subtype: BinarySubtype(v.Subtype),
+			B:       v.Data,
+		}, nil
+	case bson.ObjectID:
+		return ObjectID(v), nil
+	case bool:
+		return v, nil
+	case bson.DateTime:
+		return v.Time().UTC(), nil
+	case bson.Null, nil:
+		return Null, nil
+	case bson.Regex:
+		return Regex{
+			Pattern: v.Pattern,
+			Options: v.Options,
+		}, nil
+	case int32:
+		return v, nil
+	case bson.Timestamp:
+		return Timestamp(uint64(v.T)<<32 | uint64(v.I)), nil
+	case int64:
+		return v, nil
+	case bson.Decimal128:
+		h, l := v.GetBytes()
+
+		return Decimal128{
+			L: l,
+			H: h,
+		}, nil
+
+	default:
+		return nil, lazyerrors.Errorf("invalid BSON type %T", v)
+	}
+}
+
+// toDriver converts wirebson value to MongoDB driver value (bson.D, bson.A, etc).
+func toDriver(v any) (any, error) {
+	switch v := v.(type) {
+	// composite types
+
+	case *Document:
+		doc := make(bson.D, 0, v.Len())
+		for k, v := range v.All() {
+			val, err := toDriver(v)
+			if err != nil {
+				return nil, lazyerrors.Error(err)
+			}
+
+			doc = append(doc, bson.E{Key: k, Value: val})
+		}
+
+		return doc, nil
+
+	case *Array:
+		arr := make(bson.A, v.Len())
+		for i, v := range v.All() {
+			val, err := toDriver(v)
+			if err != nil {
+				return nil, lazyerrors.Error(err)
+			}
+
+			arr[i] = val
+		}
+
+		return arr, nil
+
+	// scalar types (in the same order as in bson package)
+
+	case float64:
+		return v, nil
+	case string:
+		return v, nil
+	case Binary:
+		return bson.Binary{
+			Subtype: byte(v.Subtype),
+			Data:    v.B,
+		}, nil
+	case ObjectID:
+		return bson.ObjectID(v), nil
+	case bool:
+		return v, nil
+	case time.Time:
+		return bson.NewDateTimeFromTime(v), nil
+	case NullType:
+		return nil, nil
+	case Regex:
+		return bson.Regex{
+			Pattern: v.Pattern,
+			Options: v.Options,
+		}, nil
+	case int32:
+		return v, nil
+	case Timestamp:
+		return bson.Timestamp{
+			T: uint32(v >> 32),
+			I: uint32(v),
+		}, nil
+	case int64:
+		return v, nil
+	case Decimal128:
+		return bson.NewDecimal128(v.H, v.L), nil
+
+	default:
+		return nil, lazyerrors.Errorf("invalid BSON type %T", v)
+	}
+}

wirebson/bson_test.go

@@ -801,6 +801,15 @@ func TestNormal(t *testing.T) {
 				require.NoError(t, err)
 				assert.Equal(t, tc.raw, raw, "actual:\n"+hex.Dump(raw))
 			})
+
+			t.Run("ToDriverFromDrive", func(t *testing.T) {
+				d, err := toDriver(tc.doc)
+				require.NoError(t, err)
+
+				doc, err := fromDriver(d)
+				require.NoError(t, err)
+				assert.Equal(t, tc.doc, doc)
+			})
 		})
 	}
 }
@@ -1111,6 +1120,20 @@ func testRawDocument(t *testing.T, rawDoc RawDocument) {
 		require.NoError(t, err)
 		assert.Equal(t, rawDoc, raw)
 	})
+
+	t.Run("ToDriverFromDriver", func(t *testing.T) {
+		doc, err := rawDoc.DecodeDeep()
+		if err != nil {
+			return
+		}
+
+		d, err := toDriver(doc)
+		require.NoError(t, err)
+
+		doc2, err := fromDriver(d)
+		require.NoError(t, err)
+		assert.Equal(t, doc, doc2)
+	})
 }
 
 func FuzzDocument(f *testing.F) {