Module: Sidekiq::Middleware
- Defined in:
- lib/sidekiq/middleware/chain.rb
Overview
Middleware is code configured to run before/after a job is processed. It is patterned after Rack middleware. Middleware exists for the client side (pushing jobs onto the queue) as well as the server side (when jobs are actually processed).
Callers will register middleware Classes and Sidekiq will create new instances of the middleware for every job. This is important so that instance state is not shared accidentally between job executions.
To add middleware for the client:
Sidekiq.configure_client do |config|
config.client_middleware do |chain|
chain.add MyClientHook
end
end
To modify middleware for the server, just call with another block:
Sidekiq.configure_server do |config|
config.server_middleware do |chain|
chain.add MyServerHook
chain.remove ActiveRecord
end
end
To insert immediately preceding another entry:
Sidekiq.configure_client do |config|
config.client_middleware do |chain|
chain.insert_before ActiveRecord, MyClientHook
end
end
To insert immediately after another entry:
Sidekiq.configure_client do |config|
config.client_middleware do |chain|
chain.insert_after ActiveRecord, MyClientHook
end
end
This is an example of a minimal server middleware:
class MyServerHook
include Sidekiq::ServerMiddleware
def call(job_instance, msg, queue)
logger.info "Before job"
redis {|conn| conn.get("foo") } # do something in Redis
yield
logger.info "After job"
end
end
This is an example of a minimal client middleware, note the method must return the result or the job will not push to Redis:
class MyClientHook
include Sidekiq::ClientMiddleware
def call(job_class, msg, queue, redis_pool)
logger.info "Before push"
result = yield
logger.info "After push"
result
end
end