Exploring the Kubernetes Clients ecosystem

Open Infra Days Asia 2021

Transcript

1. Exploring the
   Kubernetes Clients
   ecosystem
   Nabarun Pal
   

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2. $ whoami
   ● Software Engineer at VMware
   ● Release Lead for Kubernetes 1.21
   ● Kubernetes Code of Conduct Committee Member
   ● PyCon India Technical Working Group Lead
   ● CNCF GSoC Administrator
   

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3. Overview of the Kubernetes Architecture
   

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4. Source: https://docs.google.com/presentation/d/1zrfVlE5r61ZNQrmXKx5gJmBcXnoa_WerHEnTxu5SMco/edit?usp=sharing under CC BY 4.0
   

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5. Speaking with the Kubernetes API
   

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6. kubectl
   

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7. client-go
   

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8. Clients out of the Kubernetes source tree
   

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9. But, why not cURL?
   

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10. Architecture of the clients
    

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11. OpenAPI Spec
    

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12. Generator Scripts
    kubernetes-client/gen
    1. Pulls the OpenAPI Spec for the targeted Kubernetes version
    2. Runs OpenAPI Generator on the OpenAPI Spec
    3. Performs post processing tasks like cleaning up unnecessary docs etc.
    4. Patches generated code with any one-off changes
    

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13. Structure of the Python Client
    

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14. Two Repo system
    kubernetes-client/python-base
    Contains helpers for parsing config files, watching objects, leader election etc.
    

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15. Two Repo system
    kubernetes-client/python
    Operational code for manipulating objects in Kubernetes Control Plane
    

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16. Client Capabilities
    

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17. Bronze
    ● Support loading config from kube config file
    ○ Basic Auth (username/password)
    ○ X509 Client certificate (inline and referenced by file)
    ○ Bearer tokens (inline and referenced by file)
    ○ encryption/TLS (inline, referenced by file, insecure)
    ● Basic API calls such as list pods should work
    ● Works from within the cluster environment
    Silver
    ● Support watch calls
    Gold
    ● Support exec, attach, port-forward calls
    ● Proto encoding
    Ref: https://github.com/kubernetes/community/blob/master/contributors/design-proposals/api-machinery/csi-new-client-library-procedure.md#client-capabilities
    

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18. Demo Time!
    

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19. How can you help?
    

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20. ● Implement new features in the Python client
    ● Help with the releases
    ● Help the Python client achieve Gold Standard
    

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21. Thank You!!!
    @theonlynabarun
    nabarun.dev
    

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