Building Light-weight Microservices Using Redis

RedisConf18 presentation on how Redis can be leveraged to build lightweight microservices frameworks using your favorite programming language. The hydra microservice library is used as a case study. https://www.npmjs.com/package/hydra

Transcript

1. Building light-weight
   Microservices using Redis
   Carlos Justiniano – Flywheel Sports
   

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2. • Carlos Justiniano
   • 2005 World Record in Distributed Computation
   • Chief Software Architect at Flywheel Sports
   • Redis since 2011
   • @cjus on Twitter, Github
   • More about me at http://cjus.me
   About me
   

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3. Light on external complexity
   and dependencies
   Not light as in Limited
   

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5. Flywheel Sports
   • Founded in 2010
   • Featuring high-energy Indoor Stadium
   Cycling and Barre classes.
   • Performance tracking technology
   • ~1200 employees
   • 42 Studios across the U.S.
   

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6. • Three studios in the Bay Area
   • One right here in SF
   • At Market St in the Financial District
   Flywheel Sports
   • Sign up for a free class using the
   offer code: FLYREDIS
   

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7. • Last summer we prepared to
   launch FlyAnywhere
   • Our at home live streaming
   service.
   Flywheel Sports
   

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8. Flash back two years …
   

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9. We started thinking about
   embracing microservices
   

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16. Embracing microservices at Flywheel
    

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17. How hard could it be?
    

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18. %QPVCKPGTK\CVKQP
    'PVGTRTKUG5GTXKEG$WU
    &KUVTKDWVGFNQIIKPI
    /GUUCIKPI
    4GFKU
    '.-
    +PVGTUGTXKEG EQOOWPKECVKQP
    .QI5VCUJ
    

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19. Wow that’s a lot to grok!
    

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20. Lots to learn
    Small team
    Limited resources
    

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25. We’re not…
    

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26. We’re not…
    * And chances are you’re not either!
    *
    

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28. But where to begin?
    

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30. Feature checklist
    • Service discovery
    • Messaging
    • Load balancing
    • Health
    • Presence
    • Logging
    • Queuing
    

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31. Wish list
    • Super easy to use
    • Ideally a single package
    • Microservice out of the box?
    

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33. Redis as distributed
    computing glue?
    • Each microservice binds to a
    Redis cluster
    • Presence by key / expiration
    • IPC via Pub / Sub
    • Routes via set stores
    • Microservice features minimal
    dependencies?
    

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34. • Health and presence
    • Service discovery
    • Inter-service (P2P) communication
    • Load balancing and routing
    • Self registration with near
    zero configuration
    • Job queues
    Hydra Features
    

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35. Your NodeJS Microservice
    Hydra module (npmjs.org)
    Other Node
    module
    Other Node
    module
    Other Node
    module
    Other Node
    module
    Your JS code
    Other Microservice
    Hydra module (npmjs.org)
    Other Node
    module
    Other Node
    module
    Other Node
    module
    Other Node
    module
    JS code
    Other Microservice
    Hydra module (npmjs.org)
    Other
    module
    Other
    module
    Other
    module
    Other
    module
    JS code
    

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37. We used Hydra to chisel away
    at our own monoliths
    

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38. Fast forward 9 months….
    

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39. Smithsonian Museum of the American Indian
    

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40. We open sourced Hydra
    at the EmpireNode 2016 conference
    https://npmjs.com/package/hydra | $ npm i hydra
    

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42. Demos
    

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54. Demos Recap
    

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55. Redis Deep Dive
    • Presence
    • Health
    • Service discovery
    • Routes
    • Load balancing
    • Messaging
    • Queues
    • Logging
    • Configuration
    Management
    

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56. Synergy
    When the whole is greater than the sum of its parts
    where: 1 + 1 = 3
    ❤
    

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57. Redis key space
    

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58. Redis key space
    • Prefix: allows for filtering Hydra vs non-Hydra keys
    • Service Name: filtering keys of a particular service type
    • Instance ID: filtering keys for a unique service instance
    • Type: classifies the type of use – i.e. purpose of key
    Prefix Service Name Instance ID Type
    * *
    * Service Name and Instance ID don’t apply in all situations
    

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59. Example key
    hydra:service:user-svcs:636a68fb1a34493f8fc17fe77d5a1b4b:presence
    Prefix Service Name Instance ID Type
    Hydra:service user-svcs 636a68fb1a34493f8fc17fe77d5a1b4b presence
    

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60. Other keys
    

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61. Key Space Recap
    • Keys organized by segments
    • Segments can be used to filter queries
    

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62. Presence
    Is a service available?
    

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63. hydra:service:user-svcs:636a68fb1a34493f8fc17fe77d5a1b4b:presence
    Prefix Service Name Instance ID Type
    Hydra:service user-svcs 636a68fb1a34493f8fc17fe77d5a1b4b presence
    : [STRING] GET, SETEX
    Presence in Redis
    

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67. Presence Recap
    • Presence management via key presence
    

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68. Health
    Is a service healthy?
    

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69. : [STRING] GET, SETEX
    Health in Redis
    hydra:service:auth-svcs:1556536eda5e4d9089b56d0d6dd0a081:health
    Prefix Service Name Instance ID Type
    Hydra:service auth-svcs 1556536eda5e4d9089b56d0d6dd0a081 health
    

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72. Health Recap
    • Per-instance health stats
    • Managed using a string key with stringified JSON text
    • Can be used by monitoring apps
    

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73. Service Discovery
    Where can I find this service?
    

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74. : [HASH] HGET, HSET, HGETALL
    Service discovery in Redis
    hydra:service:nodes
    Prefix Type
    Hydra:service nodes
    

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81. Service Discovery Recap
    • ServiceName used to query for service information
    • Individual services store information using their unique IDs
    • Managed using Redis Hash – blazing fast!
    

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82. Routes
    What’s the path to this resource?
    

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83. : [SET] SADD, SMEMBERS
    Routes in Redis
    hydra:service:asset-svcs:service:routes
    Prefix Type
    Hydra:service service:routes
    Service Name
    asset-svcs
    

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86. Routes Recap
    • Services can publish their routes to Redis
    • Individual services store information using their unique IDs
    • Enables dynamic service aware routing
    • Managed using a Redis Set
    

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87. Load Balancing
    Distributing requests / messages
    among available services
    

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88. Load balancing using Redis
    : [STRING, HASH, SET]
    GET, SETEX, HGET, HGETALL, SADD, SMEMBERS
    hydra:service:nodes
    Prefix Type
    Hydra:service nodes
    hydra:service:asset-svcs:service:routes
    Prefix Type
    Hydra:service service:routes
    Service Name
    asset-svcs
    hydra:service:user-svcs:636a68fb1a34493f8fc17fe77d5a1b4b:presence
    Prefix Service Name Instance ID Type
    Hydra:service user-svcs 636a68fb1a34493f8fc17fe77d5a1b4b presence
    

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89. Note: scan is used instead of keys and hgets are wrapped in a multi transaction
    

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90. Load Balancing Recap
    • Works using Presence, service discover and routing features
    • Redis string, hash and sets make this possible
    

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91. Messaging
    Communicating with other services
    

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92. : [PUB/SUB] SUBSCRIBE, UNSUBSCRIBE, PUBLISH
    Messaging in Redis
    hydra:service:mc:asset-svcs:cb8c96deb5434d5b95f3cd7bcdd6851c
    Prefix
    Hydra:service
    Service Name
    asset-svcs
    Instance ID
    cb8c96deb5434d5b95f3cd7bcdd6851c
    hydra:service:mc:asset-svcs
    

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93. asset-svcs
    Hydra module (npmjs.org)
    code
    hydra:service:mc:asset-svcs
    cb8c96deb5434d5b95f3cd7bcdd6851c
    hydra:service:mc:asset-svcs:
    cb8c96deb5434d5b95f3cd7bcdd6851c
    hydra:service:mc:project-svcs:
    b4d2bbdadb514ea598d9bd08c7aef120
    hydra:service:mc:project-svcs
    project-svcs
    Hydra module (npmjs.org)
    code
    b4d2bbdadb514ea598d9bd08c7aef120
    

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95. UMF Messaging
    Standardizing messaging
    

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96. REQUIRED
    REQUIRED
    REQUIRED USER DEFINED
    

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97. client-svcs send message project-svcs receive message
    

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98. How send message works
    Standardizing messaging
    

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99. more…*
    * channels are returned as an unordered list consisting of two entries per service
    

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100. Messaging Recap
     • Needed because services are distributed!
     • Implemented using Redis Pub / Sub
     • Standardizing messaging formats is vital
     

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101. Queues
     Message queues, job queues
     

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102. : [LIST] lpush, rpush, rpoplpush, lrem
     Queues in Redis
     hydra:service:imageproc-svcs:mqrecieved
     Prefix Service Name Type
     Hydra:service imageproc-svcs mq{bin}
     hydra:service:imageproc-svcs:mqinprogress
     hydra:service:imageproc-svcs:mqincomplete
     

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103. item 11
     item 8
     item 10
     item 12
     item 9
     item 8
     item 7
     item 6
     item 5
     item 4
     item 3
     FIFO
     mqrecieved mqinprogress mqincomplete
     lpush
     item 2
     rpoplpush
     item 1 Item 0
     lrem
     rpush
     

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104. Asset-svcs queues a task for the imageproc-svcs
     imageproc-svcs dequeues task
     imageproc-svcs marks task as complete
     Inter-service
     Queuing Flow
     

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105. Queuing Recap
     • Great when we don’t need immediate message responses
     • Redis Lists using lpush and rpoplpush
     • Atomic operations FTW
     • Ease of abstractions at an application level
     

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106. Logging
     Microservice flight recorder?
     

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107. : [LIST] lrange, lpush, ltrim
     Logging in Redis
     hydra:service:imageproc-svcs:1ce584aeee24429891182180fee12f58:health:log
     Prefix Service Name Instance ID Type
     Hydra:service imageproc-svcs 1556536eda5e4d9089b56d0d6dd0a081 health:log
     

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109. Logging Recap
     • Necessary because services are distributed
     • Distributed logging
     • Redis as a Flight Recorder!
     • Implemented using lists and the lpush / ltrim commands
     

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110. Configuration Management
     Storing configs in Redis
     

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111. : [HASH] hget, hset, hkeys
     Redis for configuration management?
     hydra:service:imageproc-svcs:configs
     Prefix Service Name Type
     Hydra:service imageproc-svcs configs
     

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115. Configuration Management Recap
     • Redis can be used for configuration management
     • Statefulness is a concern
     • Redis Hash indexed by service version with
     a stringified JSON contents
     

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116. Wow, we’ve covered a lot!
     

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119. Pulling it all together
     

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123. Thank You
     @cjus : github / twitter
     http://cjus.me
     

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