Introduction

When running go run build.go build will see

go build -ldflags -w -X main.version=1.1.5-rc -X main.commit=v1.1.4+23-gdd35b31 -X main.buildstamp=1491902483 -o ./bin/grafana-server ./pkg/cmd/grafana-server

Which means

• source code input path is ./pkg/cmd/grafana-server
• binary code output path is ./bin/grafana-server
• omit the DWARF symbol table

Notes

• both -ldflags and -o are flags of build
• both -w and -X are flags of -ldflags
• full list of -ldflags flags see here https://golang.org/cmd/link/

Use go run to launch grafana-server

cd $GOPATH/src/github.com/grafana/grafana/pkg/cmd/grafana-server
go run main.go server.go web.go -homepath $GOPATH/src/github.com/grafana/grafana

Use debugger to launch grafana-server

Install delve

brew install go-delve/delve/delve

Use delve

cd $GOPATH/src/github.com/grafana/grafana/pkg/cmd/grafana-server
dlv debug -- -homepath $GOPATH/src/github.com/grafana/grafana

# grafana version 4.1.2

(dlv) break main.main
(dlv) break main.main:1
(dlv) break main.go:46
(dlv) break api.LoginPost:1
(dlv) continue
(dlv) continue
(dlv) continue
(dlv) continue

# Try login from http://localhost:3000/login

(dlv) args

# Can see the input username and password

(dlv) continue

If panic

(dlv) restart

(dlv) step-related commands

• next : step over to next source line.
• step : single step through program.
• stepout : step out of the current function.

(dlv) print-related commands

• args : print function arguments.
• breakpoints: print out info for active breakpoints.
• funcs : print list of functions.
• goroutines : print program goroutines.
• help : prints the help message.
• locals : print local variables.
• regs : print contents of CPU registers.
• sources : print list of source files.
• stack : print stack trace.
• threads : print out info for every traced thread.
• types : print list of types
• vars : print package variables.

Have tried

• delve
• godebug
• gdb

References

• https://github.com/derekparker/delve/tree/master/Documentation