Here we add a Go API for running tracing plugins within the main block import process.
As an advanced user of geth, you can now create a Go file in eth/tracers/live/, and within
that file register your custom tracer implementation. Then recompile geth and select your tracer
on the command line. Hooks defined in the tracer will run whenever a block is processed.
The hook system is defined in package core/tracing. It uses a struct with callbacks, instead of
requiring an interface, for several reasons:
- We plan to keep this API stable long-term. The core/tracing hook API does not depend on
on deep geth internals.
- There are a lot of hooks, and tracers will only need some of them. Using a struct allows you
to implement only the hooks you want to actually use.
All existing tracers in eth/tracers/native have been rewritten to use the new hook system.
This change breaks compatibility with the vm.EVMLogger interface that we used to have.
If you are a user of vm.EVMLogger, please migrate to core/tracing, and sorry for breaking
your stuff. But we just couldn't have both the old and new tracing APIs coexist in the EVM.
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Co-authored-by: Matthieu Vachon <matthieu.o.vachon@gmail.com>
Co-authored-by: Delweng <delweng@gmail.com>
Co-authored-by: Martin HS <martin@swende.se>
This change fixes two type-inconsistencies in the JS tracer:
- In most places we return byte arrays as a `Uint8Array` to the tracer. However it seems we missed doing the conversion for `ctx` fields which are passed to the tracer during `result`. They are passed as simple arrays. I think Uint8Arrays are more suitable and we should change this inconsistency. Note: this will be a breaking-change. But I believe the effect is small. If we look at our tracers we see that these fields (`ctx.from`, `ctx.to`, etc.) are used in 2 ways. Passed to `toHex` which takes both array or buffer. Or the length was measured which is the same for both types.
- The `slice` taking in `int, int` params versus `memory.slice` taking `int64, int64` params. I suggest changing `slice` types to `int64`. This should have no effect almost in any case.
We had to do this workaround because it wasn't possible to export typed arrays from
JS to []byte. This was added in dop251/goja@2352993, so we can use the better way now.
This includes a semantic change to the `callTracer` as well as `flatCallTracer`.
The value of field `gas` in the **first** call frame will change as follows:
- It previously contained gas available after initial deductions (i.e. tx costs)
- It will now contain the full tx gasLimit value
Signed-off-by: jsvisa <delweng@gmail.com>
This PR fixes OOM panic in the callTracer as well as panicing on
opcode validation errors (e.g. stack underflow) in callTracer and
prestateTracer.
Co-authored-by: Martin Holst Swende <martin@swende.se>
This makes non-JS tracers execute all block txs on a single goroutine.
In the previous implementation, we used to prepare every tx pre-state
on one goroutine, and then run the transactions again with tracing enabled.
Native tracers are usually faster, so it is faster overall to use their output as
the pre-state for tracing the next transaction.
Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>
This removes the 'time' field from logs, as well as from the tracer interface. This change makes the trace output deterministic. If a tracer needs the time they can measure it themselves. No need for evm to do this.
Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>
* eth/tracers: fix gasUsed in call tracer
* fix js tracers gasUsed
* fix legacy prestate tracer
* fix restGas in test
* drop intrinsicGas field from js tracers
* eth/tracers: pad memory slice on oob case
* eth/tracers/js: fix testfailure due to err msg capitalization
Co-authored-by: Martin Holst Swende <martin@swende.se>
This PR allows users to pass in a config object directly to the tracers. Previously only the struct logger was configurable.
It also adds an option to the call tracer which if enabled makes it ignore any subcall and collect only information about the top-level call. See #25419 for discussion.
The tracers will silently ignore if they are passed a config they don't care about.
This changes the []byte <-> Uint8Array conversion to use an
ArrayBuffer, avoiding inefficient copying of the slice data in Goja.
Co-authored-by: Felix Lange <fjl@twurst.com>
#23773 added a JS tracer which uses Goja as its engine. In this PR I remove the previous tracer which used duktape as well as remove the dependencies.
This PR also comes with 2 fixes in the Goja tracer and one small behavioural change:
I had handled errors in the native Go functions by panicing. My oversight was that Goja only handles panics with a Goja.Value as argument. The difference is panic(goja.Value) allows JS to catch the exception whereas Interrupt(error) doesn't.
There was a race in how I handled Stop.
Because of 1. some of the methods that simply return nil on error (like memory.slice) now throw an exception.
This adds a JS tracer runtime environment based on the Goja VM. The new
runtime replaces the duktape runtime, which will be removed soon.
Goja is implemented in Go and is faster for cases where the Go <-> JS
transition overhead dominates overall performance. It is faster because
duktape is written in C, and the transition cost includes the cost of using
cgo. Another reason for using Goja is that go-duktape is not maintained
anymore.
We expect the performace of JS tracing to be at least as good or better with
this change.
Aaron Chen
Brandon Liu
Sina M
Joe Netti
Delweng
jwasinger
Martin Holst Swende
Marius van der Wijden
Felix Lange
Seungbae.yu
Eduard S