Timeline

Package appdash provides a Go app performance tracing suite. Appdash allows you to trace the end-to-end performance of hierarchically structured applications. You can, for example, measure the time and see the detailed information of each HTTP request and SQL query made by an entire distributed web application. The cmd/appdash tool launches a web front-end which displays a web UI for viewing collected app traces. It is effectively a remote collector which your application can connect and send events to. Timing and application-specific metadata information can be viewed in a nice timeline view for each span (e.g. HTTP request) and it's children. The web front-end can also be embedded in your own Go HTTP server by utilizing the traceapp sub-package, which is effectively what cmd/appdash serves internally. Sub-packages for HTTP and SQL event tracing are provided for use with appdash, which allows it to function equivalently to Google's Dapper and Twitter's Zipkin performance tracing suites. The most high-level structure is a Trace, which represents the performance of an application from start to finish (in an HTTP application, for example, the loading of a web page). A Trace is a tree structure that is made up of several spans, which are just IDs (in an HTTP application, these ID's are passed through the stack via a few special headers). Each span ID has a set of Events that directly correspond to it inside a Collector. These events can be any combination of message, log, time-span, or time-stamped events (the cmd/appdash web UI displays these events as appropriate). Inside your application, a Recorder is used to send events to a Collector, which can be a remote HTTP(S) collector, a local in-memory or persistent collector, etc. Additionally, you can implement the Collector interface yourself and store events however you like.

Package godevtool is a comprehensive developer debugging toolkit for Go applications. It provides structured logging, variable inspection, performance profiling, HTTP request/response monitoring, goroutine tracking, memory analysis, database query logging, event timelines, configuration viewing, error tracking, and a real-time web dashboard -- all with zero external dependencies. The DevTool struct is the central facade that wires together 26 specialized packages. Each package can be used independently, but the facade provides a unified API and connects everything to the web dashboard for real-time visualization. All features are designed to be zero-overhead when disabled via DevTool.Disable. Core debugging: Runtime monitoring: Advanced tracing: Environment awareness: Performance intelligence: Developer experience:

Package timeline provides an implementation of a "timeline", which is a set of zero or more non-overlapping date ranges in chronological order.