Connect sign-up to Sendico Facts intake (#46)

backend/shared/database/source/majority.go

@@ -0,0 +1,25 @@
+package source
+
+import (
+	"context"
+
+	"go.mongodb.org/mongo-driver/v2/mongo"
+	"go.mongodb.org/mongo-driver/v2/mongo/options"
+	"go.mongodb.org/mongo-driver/v2/mongo/readconcern"
+	"go.mongodb.org/mongo-driver/v2/mongo/readpref"
+	"go.mongodb.org/mongo-driver/v2/mongo/writeconcern"
+)
+
+type majority struct{ Source }
+
+// Majority retains the source's lease and transaction lifecycle while requiring
+// durable writes and primary majority reads for externally visible handoffs.
+func Majority(database Source) Source { return &majority{Source: database} }
+
+func (s *majority) Acquire(ctx context.Context) (*mongo.Database, context.Context, func(), error) {
+	database, scoped, release, err := s.Source.Acquire(ctx)
+	if err != nil {
+		return nil, scoped, release, err
+	}
+	return database.Client().Database(database.Name(), options.Database().SetWriteConcern(writeconcern.Majority()).SetReadConcern(readconcern.Majority()).SetReadPreference(readpref.Primary())), scoped, release, nil
+}

backend/shared/database/source/majority_test.go

@@ -0,0 +1,40 @@
+package source
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/v2/mongo"
+	"go.mongodb.org/mongo-driver/v2/mongo/options"
+	"go.mongodb.org/mongo-driver/v2/mongo/readpref"
+	"go.mongodb.org/mongo-driver/v2/mongo/writeconcern"
+)
+
+type trackedSource struct {
+	database *mongo.Database
+	released bool
+}
+
+func (s *trackedSource) Acquire(ctx context.Context) (*mongo.Database, context.Context, func(), error) {
+	return s.database, ctx, func() { s.released = true }, nil
+}
+
+func TestMajorityPreservesSourceLifetime(t *testing.T) {
+	client, err := mongo.Connect(options.Client().ApplyURI("mongodb://localhost:27017").SetWriteConcern(&writeconcern.WriteConcern{W: 1}).SetReadPreference(readpref.Secondary()))
+	require.NoError(t, err)
+	t.Cleanup(func() { require.NoError(t, client.Disconnect(context.Background())) })
+	underlying := &trackedSource{database: client.Database("handoff")}
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	database, scoped, release, err := Majority(underlying).Acquire(ctx)
+	require.NoError(t, err)
+	require.Same(t, client, database.Client())
+	require.Equal(t, "handoff", database.Name())
+	require.Equal(t, ctx, scoped)
+	require.False(t, underlying.released)
+	release()
+	require.True(t, underlying.released)
+	_, _, _, err = Majority(Fixed(nil)).Acquire(ctx)
+	require.Error(t, err)
+}