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vendor/go.mongodb.org/mongo-driver/x/mongo/driverlegacy/write.go

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+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+
+package driverlegacy
+
+import (
+	"context"
+
+	"go.mongodb.org/mongo-driver/bson"
+	"go.mongodb.org/mongo-driver/mongo/writeconcern"
+	"go.mongodb.org/mongo-driver/x/mongo/driver/description"
+	"go.mongodb.org/mongo-driver/x/mongo/driver/session"
+	"go.mongodb.org/mongo-driver/x/mongo/driver/topology"
+	"go.mongodb.org/mongo-driver/x/mongo/driver/uuid"
+	"go.mongodb.org/mongo-driver/x/network/command"
+)
+
+// Write handles the full cycle dispatch and execution of a write command against the provided
+// topology.
+func Write(
+	ctx context.Context,
+	cmd command.Write,
+	topo *topology.Topology,
+	selector description.ServerSelector,
+	clientID uuid.UUID,
+	pool *session.Pool,
+) (bson.Raw, error) {
+
+	if cmd.Session != nil && cmd.Session.PinnedServer != nil {
+		selector = cmd.Session.PinnedServer
+	}
+	ss, err := topo.SelectServerLegacy(ctx, selector)
+	if err != nil {
+		return nil, err
+	}
+
+	desc := ss.Description()
+	conn, err := ss.ConnectionLegacy(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	if !writeconcern.AckWrite(cmd.WriteConcern) {
+		go func() {
+			defer func() { _ = recover() }()
+			defer conn.Close()
+
+			_, _ = cmd.RoundTrip(ctx, desc, conn)
+		}()
+
+		return nil, command.ErrUnacknowledgedWrite
+	}
+	defer conn.Close()
+
+	// If no explicit session and deployment supports sessions, start implicit session.
+	if cmd.Session == nil && topo.SupportsSessions() {
+		cmd.Session, err = session.NewClientSession(pool, clientID, session.Implicit)
+		if err != nil {
+			return nil, err
+		}
+		defer cmd.Session.EndSession()
+	}
+
+	return cmd.RoundTrip(ctx, desc, conn)
+}
+
+// Retryable writes are supported if the server supports sessions, the operation is not
+// within a transaction, and the write is acknowledged
+func retrySupported(
+	topo *topology.Topology,
+	desc description.SelectedServer,
+	sess *session.Client,
+	wc *writeconcern.WriteConcern,
+) bool {
+	return topo.SupportsSessions() &&
+		description.SessionsSupported(desc.WireVersion) &&
+		!(sess.TransactionInProgress() || sess.TransactionStarting()) &&
+		writeconcern.AckWrite(wc)
+}