Sidecar

  • Problem

    • Peripheral tasks such as Monitoring, Logging etc are critical to most applications and often integrated within them.

    • However, these tasks run alongside the same process as the application which is potentially inefficient and points to improper separation of concerns.

    • Plus, outages caused in these monitoring and logging components could severely impact the entire application functions.

  • Solution

    • Co-locate as Sidecar

      • Uses

        • PRoxy

          • Egress traffic using https

          • Internal service traffic using https

      • How it works

        • Co-locate the set of tasks along with the application but place them in their process or container as a Sidecar

        • Sidecars are typically small/pluggable components and can be written in different languages

        • Both application and sidecar are deployed as a single unit, therefore latency is low

        • The sidecar can be used for modifying how the application container works without having to make any changes to the code

        • The sidecar is bolted to the application and its lifecycle is dependent on the application

        • If the sidecar container logic gets complex or tightly coupled with the main application, it may better be integrated with the main application’s code instead

      • example

        • A common example of the sidecar is the literal sidecar attached to a motorcycle — working as a single unit

        • The sidecar enhances the usability of the motorcycle by increasing passenger capacity

        • The sidecar could be made by another company and need not be bought from the motorcycle manufacturer — providing modularity and flexibility of choice

        • It does not have an engine of its own but relies on the engine of the actual motorcycle. If the motorcycle stops, the sidecar stops

Sidecar patterns

PreviousRetryNextStrangler pattern

Last updated