Redmine

h2. Solid Queue configuration

"Solid Queue":https://github.com/rails/solid_queue is a Database-backed Active Job backend. I've tested to following install and configuration steps on a fresh Debian/GNU Linux 12 with Redmine 6.0.6 and Solid Queue 1.2.0.

h3. 1. Install solid_queue

# Add the gem as dependency in @Gemfile.local@ file. If the file doesn't exist, you need to create it.

<pre>

gem 'solid_queue'

</pre>

# Run @bundle install@ to install the dependency

h3. 2. Configure Redmine database to setup tables for solid_queue (single database case)

Run following to 

<pre>

bin/rails solid_queue:install

</pre>

Write db/migrate/20250701000000_add_solid_queue_tables.rb as following:

<pre>

cat <<EOF > db/migrate/20250701000000_add_solid_queue_tables.rb

class AddSolidQueueTables < ActiveRecord::Migration[7.2]

  def change

$(sed -e '1 d' -e '$ d' db/queue_schema.rb | sed -e 's|^  |    |')

  end

end

EOF

</pre>

h3. 3. Configure Redmine to use @solid_queue@ as backend

# Create @config/additional_environment.rb@ file if the file does not exist by copying the existing example file:

<pre>

cp config/additional_environment.rb.example config/additional_environment.rb

</pre>

# Add the below config line to the file:

<pre>

config.active_job.queue_adapter = :solid_queue

</pre>

# Restart Redmine to reload the configuration file.

h3. 4. Test the configuration

# Browse to Information tab from Redmine Administration page and check the mailer queue value:

<pre>

  Mailer queue                   ActiveJob::QueueAdapters::SolidQueueAdapter

</pre> 

# Perform some actions in Redmine in order to trigger some notifications emails. In this step, Redmine only pushes the background jobs to SolidQueue backend.

# Temporary start Solid Queue supervisor in order to process the queue and send the emails:

<pre>

RAILS_ENV=production bin/jobs start

</pre>

    Output example of startup process:

<pre>

I, [2025-07-24T11:53:53.590961 #24399]  INFO -- : SolidQueue-1.2.1 Started Supervisor (40.1ms)  pid: 24399, hostname: "vagrant", process_id: 5, name: "supervisor-9318434042b90e70bf75"

I, [2025-07-24T11:53:53.642738 #24405]  INFO -- : SolidQueue-1.2.1 Started Dispatcher (43.7ms)  pid: 24405, hostname: "vagrant", process_id: 6, name: "dispatcher-6709740a9c0eb52cc355", polling_interval: 1, batch_size: 500, concurrency_maintenance_interval: 600

I, [2025-07-24T11:53:53.647923 #24408]  INFO -- : SolidQueue-1.2.1 Started Worker (42.7ms)  pid: 24408, hostname: "vagrant", process_id: 7, name: "worker-beadd9266ccccca675d0", polling_interval: 0.1, queues: "*", thread_pool_size: 3

I, [2025-07-24T11:53:53.686615 #24412]  INFO -- : SolidQueue-1.2.1 Started Scheduler (76.3ms)  pid: 24412, hostname: "vagrant", process_id: 8, name: "scheduler-b85c19cbe69292d9a6af", recurring_schedule: ["clear_solid_queue_finished_jobs"]

</pre>

    Output example of job processing:

<pre>

I, [2025-07-24T11:54:50.951148 #24408]  INFO -- : [ActiveJob] [Mailer::DeliveryJob] [d02bcf2d-73a3-42e9-a0fb-2832679cfc4b] Performing Mailer::DeliveryJob (Job ID: d02bcf2d-73a3-42e9-a0fb-2832679cfc4b) from SolidQueue(mailers) enqueued at 2025-07-24T11:54:50.682261303Z with arguments: "Mailer", "issue_edit", "deliver_now", {:args=>[#<GlobalID:0x00007a885a2747e8 @uri=#<URI::GID gid://redmine-app/User/1>>, #<GlobalID:0x00007a885a2aff78 @uri=#<URI::GID gid://redmine-app/Journal/1>>]}

I, [2025-07-24T11:54:51.421949 #24408]  INFO -- : [ActiveJob] [Mailer::DeliveryJob] [d02bcf2d-73a3-42e9-a0fb-2832679cfc4b] Performed Mailer::DeliveryJob (Job ID: d02bcf2d-73a3-42e9-a0fb-2832679cfc4b) from SolidQueue(mailers) in 559.55ms

</pre>

# If everything went well, stop the command. 

h3. 5. Configure Solid Queue supervisor to run as a system service

# Write @/etc/systemd/system/redmine_solid_queue.service@ file. example:

<pre>

[Unit]

Description=Solid Queue for Redmine

After=network.target nss-lookup.target remote-fs.target

[Service]

Type=simple

User=vagrant

Group=vagrant

WorkingDirectory=/opt/redmine

Environment=RAILS_ENV=production

ExecStart=/home/vagrant/.local/share/mise/shims/bundle exec bin/jobs start

TimeoutSec=300

ExecReload=/bin/kill -TSTP ${MAINPID}

ExecStop=/bin/kill -INT ${MAINPID}

RestartSec=1

Restart=on-failure

SyslogIdentifier=redmine_solid_queue

[Install]

WantedBy=multi-user.target

</pre>

# Enable and start the service:

<pre>

sudo systemctl enable redmine_solid_queue.service

sudo systemctl start redmine_solid_queue.service

</pre>

# Test again the email notifications