in Action RabbitMQ Distributed Messaging for Everyone ALVARO VIDELA JASON J.W. WILLIAMS /II MANNING Shelter Island

Transcription

1 RabbitMQ in Action Distributed Messaging for Everyone ALVARO VIDELA JASON J.W. WILLIAMS /II MANNING Shelter Island

2 contents foreword xv preface xvii acknowledgments xix about this book xxi about the cover illustration xxiv 1 Pulling RabbitMQ out ofthe hat Living in other people's dungeons AMQP to the rescue A brief history of RabbitMQ Picking RabbitMQ out of the hat (and other open options) Installing RabbitMQ on Unix systems 8 Why environment matters living la vida Erlang 8 Getting package 9 Setting up the folder structure 9 Firing for the first time Summary 10 the Rabbit up Understanding messaging Consumers and producers (not an economics lesson) Building from the bottom: queues Getting together: exchanges and bindings 20 ix

3 . Private CONTENTS 2.4 Multiple tenants: virtual hosts and separation Where's my message? Durability and you Putting it all together: a day in the life of a message Using publisher confirms to verify delivery Summary 35 Running and administering Rabbit Server management 38 Starting nodes 38 Stopping nodes 39 Stopping and restarting the application: what's the difference? configuration files Asking permission 43 40* Rabbit Managing users 43 * Rabbit's permissions system Checking up 47 Viewing statistics 47* UnderstandingRabbitMQ's logs Fixing a bad Rabbit: troubleshooting 55 badrpc, nodedown and other Erlang-induced problems Summary 59 Solvingproblems with Rabbit: coding and patterns A decoupling story: what pushes us to messaging 61 An asynchronous state of mind (separating requests and actions) 61 * Affording scale: a world without load balancers 63 Zero-effort APIs: why be locked intojust one language'? Fire-and-forget models 65 Sending alerts 65 * Parallel processing Remember me: RPC over RabbitMQ and waiting for answers 80 queues and sending acknowledgements 81 * RPC with replyjlo 82 SimpleJSON 4.4 Summary 86 Clustering and dealing with failure Batteries included: RabbitMQ clustering Architecture of a cluster 89 * Queues in a cluster 89 Distributing RAM or a disk? 92 exchanges 91 * Am I

4 CONTENTS 5.3 Setting up a cluster on your laptop Distributing the nodes to more machines Upgrading cluster nodes Mirrored queues and preserving messages 101 Declaring and using mirrored queues 101 Under the hood with mirrored queues Summary 105 Writing code that survives failure Load balancing your Rabbits 108 Installing HAProxy 110 Configuring HAProxy Lost connections and failing servers Summary 119 clients between Warrens and Shovels: failover and replication Warrens: another way of clustering Setting up load balancer-based master/slave clusters Long-distance communication and replication 126 Shoveling your Rabbits: an introduction to the Shovel plugin 126 Installing Shovel 129 Configuring and running Shovel 130 7A Summary 136 AdministeringRabbitMQfrom the Web Beyond rabbitmqctl: the RabbitMQ Management plugin 138 Whyyou need the Management plugin 138 Management plugin features 138 Enabling the Management plugin Managing RabbitMQ from the web console 141 Monitoring theerlangvm 141 Importing configurationfrom fsonfiles Managing users from the web console 143 Creating users 143 Managing users'permissions Managing exchanges and queues console 146 from the web Listing queues 148 Creating queues 149

5 CONTENTS 8.5 Back to the command line 150 Why another CU? 150 CLI administration the easier way 151 Installing rabbitmqadmin script 152 Purging queues, creating exchanges, and more Summary 153 Controlling Rabbit with the RESTAPI What can you do with the RabbitMQ REST API? Granting your clients access Accessing statistics Automating vhost and user provisioning Summary 165 Monitoring: Houston, we have a problem RabbitMQ monitoring: keeping an eye on your warren 168 Writing health checks for Nagios 168 Checking that RabbitMQ is alive with AMQP simulation checks 170 Checking aliveness with the REST API 172 changes 176 Monitoring your Creating a watchdog for configuration cluster status Making sure consumers are consuming 185 Monitoring queue levels through AMQP 186 Using the REST API to watch queue levels 190 Rules ofthumb for establishing a queue count baseline Summary 194 Supercharging and securingyour Rabbit The need for speed 196 Message durability 196 Message acknowledgment 197 Routing algorithm and bindings 197 Delivering messages Memory usage and process limits 200 Memory usage 201 Erlangprocess 11.3 SSL connections 204 count 203 SSL certificates 204 Setting up a certificate authority 206 Generating the root certificate 209 Generating the server certificates 210 Generating the client certificates 211 Enabling SSL listeners in RabbitMQ 211* Testing your RabbitMQ SSL setup Summary 215

6 CONTENTS xiii 12 Smart Rabbits: extending RabbitMQ RabbitMQ plugins 217 What can you do with plugins? 217 Where do you find plugins? 218 Installingplugins 218 Removing plugins Making your own plugins 221 Getting the RabbitMQPublic Umbrella 222- Setting up thefolder structure 223 Including the plugin build system 223 Creating the Erlang application file Creating your custom exchange module 225 Registeringyour exchange with RabbitMQ 227 Implementing the exchange behaviour 230 Compilingyour custom exchange 236 Taking your plugin for a test drive Summary 243 and.net 244 appendix A Using Rabbit fromjava appendix B Online resources 270 appendix C Installing RabbitMQ on Windows 275 index 279