gcp function panic

gistfile1.txt

Function panic: runtime error: invalid memory address or nil pointer dereference

goroutine 20 [running]:
runtime/debug.Stack(0xc000132f20, 0x9070c0, 0xdd12d0)
	/go/src/runtime/debug/stack.go:24 +0xa7
main.executeFunction.func1(0xa3e620, 0xc0002421c0)
	/tmp/sgb/staging/srv/worker.go:116 +0x6e
panic(0x9070c0, 0xdd12d0)
	/go/src/runtime/panic.go:513 +0x1b9
extractor.F(0x2aba25e19080, 0xc0001a50e0, 0xc000023510, 0xe, 0xc000024ee0, 0x17, 0xc000023520, 0xf, 0xc000023508, 0x8, ...)
	/tmp/sgb/staging/srv/files/function.go:32 +0x531
reflect.Value.call(0x8ee7a0, 0x9d4230, 0x13, 0x9ae56b, 0x4, 0xc000133b68, 0x2, 0x2, 0xc000133b40, 0xc0001a50e0, ...)
	/go/src/reflect/value.go:447 +0x449
reflect.Value.Call(0x8ee7a0, 0x9d4230, 0x13, 0xc000133b68, 0x2, 0x2, 0x0, 0x0, 0xc000024da0)
	/go/src/reflect/value.go:308 +0xa4
main.executeFunction(0xa3e620, 0xc0002421c0, 0xc00025e300)
	/tmp/sgb/staging/srv/worker.go:187 +0x7a1
net/http.HandlerFunc.ServeHTTP(0x9d4f80, 0xa3e620, 0xc0002421c0, 0xc00025e300)
	/go/src/net/http/server.go:1964 +0x44
net/http.(*ServeMux).ServeHTTP(0xde3ae0, 0xa3e620, 0xc0002421c0, 0xc00025e300)
	/go/src/net/http/server.go:2361 +0x127
net/http.serverHandler.ServeHTTP(0xc00008f790, 0xa3e620, 0xc0002421c0, 0xc00025e300)
	/go/src/net/http/server.go:2741 +0xab
net/http.(*conn).serve(0xc000250140, 0xa3eb60, 0xc000256380)
	/go/src/net/http/server.go:1847 +0x646
created by net/http.(*Server).Serve
	/go/src/net/http/server.go:2851 +0x2f5