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pythonflasktracejaeger

I'm using Jaeger tracing python functions. Do i have to create spans in every function manually?

I've found an example: https://medium.com/velotio-perspectives/a-comprehensive-tutorial-to-implementing-opentracing-with-jaeger-a01752e1a8ce

I have a pretty large codebase and I really don't want to modify every function by adding a line like ' with tracer.start_span('booking') as span:'. Is there any way to do it?

Thanks in advance.

Solution

  • Jaeger is a distributed tracer, inspired by Google's Dapper paper, and so it is mainly used for tracing communication between different processes in a microservices / distributed system architecture, not so much for portions of code inside an application.

    The way Jaeger is introduced into most applications is to integrate it into the part of the application that is receiving requests from the network. For example, if your Python application is receiving HTTP requests using Django or Flask, or other types of requests (e.g. gRPC) using some other framework, there will probably be a project somewhere on the internet that lets you hook Jaeger into your framework with a couple of lines of code. For the most popular frameworks, the Jaeger docs point to opentracing-contrib as a good source for these "client libraries".

    While making extra tracing calls inside an application is not unheard of or discouraged with d.tracers, it's not something that tends to happen a lot, because d.tracers are typically used in microservices environments where the interactions between components are more important than what's happening inside the components.

    If you do want to create tracing records inside an application, then it would be very unusual to do tracing of every single function. Instead, tracing inside an application would typically be done at the boundary of components in a modular monolith, i.e. when one component calls into another component.

    Lastly, if what you really want is performance analysis of your single Python application at the level of each function, and you don't care about it's interaction with other applications in your system (maybe you only have the one?), then Jaeger is probably not the right tool. In that case, you would probably want to look for an Application Performance Monitoring or APM tool that works with Python and suits your needs.