Keep watching and extending features of gRPC

mercari.go #5

Transcript

1. Keep watching and extending
   features of gRPC
   mercari.go #5
   

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2. @kazegusuri
   ● Merpay Backend Engineer
   ● Architect Team
   2015/11 2017/01 2018/01
   SRE & Platform Platform Payment & Architect
   

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3. Objective of this talk
   Just I talk about gRPC
   01
   Tell features of gRPC
   Just I talk about gRPC
   03
   02
   

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4. ⚠Disclaimers⚠
   ● The contents are not for beginners of gRPC
   ● I am talking forever once started. You will fall asleep.
   ● The details are not described in this slide, just I talk
   ○ You are lucky! or unlucky for boring time
   ● This slide was originally created for internal meet up in merpay
   ○ for mercari employees
   

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5. My information source of gRPC
   ● github.com/grpc/proposal
   ○ gRFC
   ● github.com/grpc/grpc-go
   ○ read almost all PRs
   ● github.com/grpc/grpc
   ○ no longer read
   ● Twitter
   ○ search grpc!!
   

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6. gRFC
   ● Design proposals for substantial feature changes
   ● Public disucssion not only inside Google
   ○ Protobuf is still Google product.. not community
   ● Looks effective to keep consistent features in all language impls.
   ● Recommend to read merged docs for everyone
   

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7. Recommended documentations
   ● github.com/grpc/grpc-go/Documentation
   ○ Docs for how to use features in grpc-go
   ○ Actively updated recently
   ● github.com/grpc/proposal
   ○ gRFC for new features
   ● github.com/grpc/grpc/doc
   ○ Useful specs still exist
   ○ not active for spec in favor of gRFC?
   

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8. gRPC history
   ● 2015/02/25 Opensourced
   ● 2016/01/11 (First use in Mercari)
   ● 2016/07/26 (Protobuf3 v3.0.0)
   ● 2016/08/23 Generally available
   ● 2017/03/01 Became a CNCF project
   

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9. Features of grpc-go
   Now I start to talk about new features of grpc-go
   for each releases
   

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10. Before v1.0(GA)
    ● 2016/01/11 (First use in Mercari)
    ● 2016/01/26 Compression (deprecated)
    ● 2016/04/19 Server Interceptor
    ● 2016/04/23 (GoCon 2016 Spring)
    ● 2016/06/01 Balancer V1 (deprecated)
    ● 2016/06/29 Server Reflection
    ● 2016/07/27 Graceful Shutdown
    ● 2016/09/03 Client Interceptor
    

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11. v1.0 2016/07/12 (~v1.2)
    ● stats 2017/01/10
    ○ grpc.StatsHandler()
    ○ Various stats provided per requests/connections
    ○ OpenCensus uses this feature for instrumentation
    ● service config 2016/12/20
    ○ grpc.WithServiceConfig() (deprecated)
    ○ services/methods configurations dynamically pupulated
    ● tap 2016/11/08
    ○ grpc.InTapHandle()
    ○ called in very early stage after connected
    ○ I don’t know the use case...
    

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12. v1.2 2017/03/21
    ● keepalive
    ○ grpc.KeepaliveParams(), grpc.KeepaliveEnforcementPolicy()
    ○ Read grpc-go/Documentation/keepalive.md
    v1.3 2017/04/29
    ● status
    ○ Introduced status package, which responsible for handling gRPC errors
    ○ Read grpc-go/Documentation/rpc-errors.md
    

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13. v1.4 2017/06/08
    ● CallOption
    ○ credentials.PerRPCCredentials
    ○ Set credential(metadata) per request
    ○ Read grpc-go/Documentation/grpc-auth-support.md
    ● CallOption
    ○ grpc.Max[Send,Recv]MsgSize, grpc.MaxCall[Send,Recv]MsgSize
    ○ Limit max message size in both client/server side
    v1.5 2017/07/20
    ● No remarkable features
    

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14. v1.6 2017/08/31
    ● status
    ○ details support in server side
    ● DNS resolver (deprecated)
    ○ legacy resolver API called naming
    v1.7 2017/10/12
    ● balancer, resolver
    ○ V2? API by gRFC L9
    ○ Registration API for balancer, resolver
    ○ Resolver is used depending on scheme of an address in grpc.DialContext
    

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15. v1.8 2017/11/27
    ● client-side retry
    ○ transparent retry in client by gRFC A6
    ○ retry to send a request when failure without sending any requests
    ● encoding
    ○ Registration API for grpc.Compressor interface for compress/decompress a message
    ○ Now server respects encoding/accept-encoding automatically!
    ○ Read grpc-go/Documentation/compression.md
    v1.9 2018/01/03
    ● No remarkable features
    

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16. v1.10 2018/02/16
    ● encoding
    ○ Registration API for grpc.Codec interface for marshal/unmarshal a message
    ○ Now we can change a codec per call, not per connection(DialOption)!
    ○ Read grpc-go/Documentation/encoding.md
    v1.11 2018/03/28
    ● credentials/alts
    ○ ALTS: Application Layer Transport Security
    

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17. v1.12 2018/05/09
    ● stickness
    ○ requested server is determined by sessionid value of metadata
    ● channelz
    ○ gRFC A14
    ○ expose internal details about connections
    v1.13 2018/06/20
    ● No remarkable features
    

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18. v1.14 2018/08/01
    ● client-side retry
    ○ gRFC A6
    ○ client library handles retry by ServiceConfig per Method/StatusCode
    ● stickness
    ○ Reverted!!!
    ○ re-considering to implement balancer/resolver-base
    v1.15 2018/09/15
    ● No remarkable features
    

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19. v1.16 2018/10/24
    ● healthcheck
    ○ Watch method in server
    ● channelz
    ○ added tracing event by gRFC A3
    v1.17 2018/12/05
    ● binarylog
    ○ gRFC A16
    ○ official logging mechanism for message,metadata as protobuf
    ● healthcheck
    ○ client-side health check by gRFC A17
    

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20. Extend the features
    ● interceptor
    ○ github.com/mercari/go-grpc-interceptor
    ■ no longer used…
    ○ internal usecase
    ■ DataDog for instrumentation
    ■ Notification with Sentry in case of unexpected errors like Unknown/Internal
    ○ middlewares for gRPC to resolve common use cases
    ● resolver
    ○ custom resolver for kubernetes specific named k8sdns
    ○ official dns resolver is not suitable for our use case
    

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21. Extend the features
    ● reflection
    ○ kazegusuri/grpcurl
    ○ Easy to call gRPC method like curl without grpc-gateway
    ● channelz
    ○ kazegusuri/channelzcli
    ○ To observe state of gRPC connections for debugging
    

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22. gRPC with protoc plugin
    ● kazegusuri/go-proto-zap-marshaler
    ○ generate go function to log proto message with zap
    ● kazegusuri/go-proto-anonymizer
    ○ generate go function to filter credentials or secrets fields in message
    

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23. Extend the features (idea)
    ● service config
    ○ clients can know configs like retry policy, timeout
    ○ difficult to use DNS, how to provide…? e.g. custom resolver
    ● encoding (codec)
    ○ CSV/TSV codec…!
    ○ message passthrough gRPC proxy without any marshaling/unmarshaling
    ● stickness
    ○ use custom balancer instead
    ● binarylog
    ○ consider to use application log if better than interceptor
    

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