fixing_replication_bug_new branch on Rails 5.1 sending write requests to slave

[vibro]

I'm trying to set up octopus with a fully replicated configuration, one master and one slave. I've been having issues with Rails 5.1 compatibility so I tried your feature branch fixing_replication_bug_new as specified in #440. Unfortunately, this configuration seems to send all write requests to the slave and nothing to the master.

shards.yml:

  replicated: true
  fully_replicated: true
  environments:
   - staging
  staging:
    slave1:
      adapter: postgresql
      host: slave1.host.com
      password: <%= ENV['DB_PASSWORD'] %>
      port: 5432
      database: my_db_name

Trying to perform an update (logging in a user):

D, [2017-09-15T13:04:33.710487 #30826] DEBUG -- :    (0.7ms)  BEGIN
D, [2017-09-15T13:04:33.716329 #30826] DEBUG -- : [Shard: slave1]  SQL (1.4ms)  UPDATE "users" SET "current_sign_in_at" = $1, "last_sign_in_at" = $2, "sign_in_count" = $3, "updated_at" = $4 WHERE "users"."id" = $5  [["current_sign_in_at", "2017-09-15 17:04:33.708809"], ["last_sign_in_at", "2017-09-14 20:52:57.704370"], ["sign_in_count", 8371], ["updated_at", "2017-09-15 17:04:33.711694"], ["id", 1]]
D, [2017-09-15T13:04:33.717190 #30826] DEBUG -- :    (0.6ms)  ROLLBACK
I, [2017-09-15T13:04:33.717740 #30826]  INFO -- : Completed 500 Internal Server Error in 71ms (ActiveRecord: 14.5ms)
F, [2017-09-15T13:04:33.719418 #30826] FATAL -- :   
F, [2017-09-15T13:04:33.719493 #30826] FATAL -- : ActiveRecord::StatementInvalid (PG::ReadOnlySqlTransaction: ERROR:  cannot execute UPDATE in a read-only transaction
: UPDATE "users" SET "current_sign_in_at" = $1, "last_sign_in_at" = $2, "sign_in_count" = $3, "updated_at" = $4 WHERE "users"."id" = $5):

In Gemfile:
gem 'ar-octopus', git: 'https://github.com/thiagopradi/octopus.git', branch: 'fixing_replication_bug_new'

I can't use the 0.9.1 version of this gem because it seems to have other compatibility issues with 5.1.