prysm-pulse/api/client/beacon/client.go
Raul Jordan 84916672c6
Remove Eth2-Types Dependency in Prysm (#10578)
* replace eth2 types

* replace protos

* regen proto

* replace

* gaz

* deps

* amend

* regen proto

* mod

* gaz

* gaz

* ensure build

* ssz

* add dep

* no more eth2 types

* no more eth2

* remg

* all builds

* buidl

* tidy

* clean

* fmt

* val serv

* gaz

Co-authored-by: Preston Van Loon <preston@prysmaticlabs.com>
2022-04-29 10:32:11 -04:00

446 lines
14 KiB
Go

package beacon
import (
"bytes"
"context"
"encoding/json"
"fmt"
"io"
"net"
"net/http"
"net/url"
"path"
"regexp"
"sort"
"strconv"
"text/template"
"time"
"github.com/prysmaticlabs/prysm/network/forks"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/pkg/errors"
"github.com/prysmaticlabs/prysm/beacon-chain/rpc/apimiddleware"
types "github.com/prysmaticlabs/prysm/consensus-types/primitives"
"github.com/prysmaticlabs/prysm/encoding/bytesutil"
ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
log "github.com/sirupsen/logrus"
)
const (
getSignedBlockPath = "/eth/v2/beacon/blocks"
getBlockRootPath = "/eth/v1/beacon/blocks/{{.Id}}/root"
getForkForStatePath = "/eth/v1/beacon/states/{{.Id}}/fork"
getWeakSubjectivityPath = "/eth/v1/beacon/weak_subjectivity"
getForkSchedulePath = "/eth/v1/config/fork_schedule"
getStatePath = "/eth/v2/debug/beacon/states"
getNodeVersionPath = "/eth/v1/node/version"
)
// StateOrBlockId represents the block_id / state_id parameters that several of the Eth Beacon API methods accept.
// StateOrBlockId constants are defined for named identifiers, and helper methods are provided
// for slot and root identifiers. Example text from the Eth Beacon Node API documentation:
//
// "Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
// <slot>, <hex encoded blockRoot with 0x prefix>."
type StateOrBlockId string
const (
IdFinalized StateOrBlockId = "finalized"
IdGenesis StateOrBlockId = "genesis"
IdHead StateOrBlockId = "head"
IdJustified StateOrBlockId = "justified"
)
// IdFromRoot encodes a block root in the format expected by the API in places where a root can be used to identify
// a BeaconState or SignedBeaconBlock.
func IdFromRoot(r [32]byte) StateOrBlockId {
return StateOrBlockId(fmt.Sprintf("%#x", r))
}
// IdFromRoot encodes a Slot in the format expected by the API in places where a slot can be used to identify
// a BeaconState or SignedBeaconBlock.
func IdFromSlot(s types.Slot) StateOrBlockId {
return StateOrBlockId(strconv.FormatUint(uint64(s), 10))
}
// idTemplate is used to create template functions that can interpolate StateOrBlockId values.
func idTemplate(ts string) func(StateOrBlockId) string {
t := template.Must(template.New("").Parse(ts))
f := func(id StateOrBlockId) string {
b := bytes.NewBuffer(nil)
err := t.Execute(b, struct{ Id string }{Id: string(id)})
if err != nil {
panic(fmt.Sprintf("invalid idTemplate: %s", ts))
}
return b.String()
}
// run the template to ensure that it is valid
// this should happen load time (using package scoped vars) to ensure runtime errors aren't possible
_ = f(IdGenesis)
return f
}
// ClientOpt is a functional option for the Client type (http.Client wrapper)
type ClientOpt func(*Client)
// WithTimeout sets the .Timeout attribute of the wrapped http.Client.
func WithTimeout(timeout time.Duration) ClientOpt {
return func(c *Client) {
c.hc.Timeout = timeout
}
}
// Client provides a collection of helper methods for calling the Eth Beacon Node API endpoints.
type Client struct {
hc *http.Client
host string
scheme string
}
// NewClient constructs a new client with the provided options (ex WithTimeout).
// `host` is the base host + port used to construct request urls. This value can be
// a URL string, or NewClient will assume an http endpoint if just `host:port` is used.
func NewClient(host string, opts ...ClientOpt) (*Client, error) {
host, err := validHostname(host)
if err != nil {
return nil, err
}
c := &Client{
hc: &http.Client{},
scheme: "http",
host: host,
}
for _, o := range opts {
o(c)
}
return c, nil
}
func validHostname(h string) (string, error) {
// try to parse as url (being permissive)
u, err := url.Parse(h)
if err == nil && u.Host != "" {
return u.Host, nil
}
// try to parse as host:port
host, port, err := net.SplitHostPort(h)
if err != nil {
return "", err
}
return fmt.Sprintf("%s:%s", host, port), nil
}
// NodeURL returns a human-readable string representation of the beacon node base url.
func (c *Client) NodeURL() string {
u := &url.URL{
Scheme: c.scheme,
Host: c.host,
}
return u.String()
}
func (c *Client) urlForPath(methodPath string) *url.URL {
u := &url.URL{
Scheme: c.scheme,
Host: c.host,
}
u.Path = path.Join(u.Path, methodPath)
return u
}
type reqOption func(*http.Request)
func withSSZEncoding() reqOption {
return func(req *http.Request) {
req.Header.Set("Accept", "application/octet-stream")
}
}
// get is a generic, opinionated GET function to reduce boilerplate amongst the getters in this package.
func (c *Client) get(ctx context.Context, path string, opts ...reqOption) ([]byte, error) {
u := c.urlForPath(path)
log.Printf("requesting %s", u.String())
req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
if err != nil {
return nil, err
}
for _, o := range opts {
o(req)
}
r, err := c.hc.Do(req)
if err != nil {
return nil, err
}
defer func() {
err = r.Body.Close()
}()
if r.StatusCode != http.StatusOK {
return nil, non200Err(r)
}
b, err := io.ReadAll(r.Body)
if err != nil {
return nil, errors.Wrap(err, "error reading http response body from GetBlock")
}
return b, nil
}
func renderGetBlockPath(id StateOrBlockId) string {
return path.Join(getSignedBlockPath, string(id))
}
// GetBlock retrieves the SignedBeaconBlock for the given block id.
// Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
// <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
// for the named identifiers.
// The return value contains the ssz-encoded bytes.
func (c *Client) GetBlock(ctx context.Context, blockId StateOrBlockId) ([]byte, error) {
blockPath := renderGetBlockPath(blockId)
b, err := c.get(ctx, blockPath, withSSZEncoding())
if err != nil {
return nil, errors.Wrapf(err, "error requesting state by id = %s", blockId)
}
return b, nil
}
var getBlockRootTpl = idTemplate(getBlockRootPath)
// GetBlockRoot retrieves the hash_tree_root of the BeaconBlock for the given block id.
// Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
// <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
// for the named identifiers.
func (c *Client) GetBlockRoot(ctx context.Context, blockId StateOrBlockId) ([32]byte, error) {
rootPath := getBlockRootTpl(blockId)
b, err := c.get(ctx, rootPath)
if err != nil {
return [32]byte{}, errors.Wrapf(err, "error requesting block root by id = %s", blockId)
}
jsonr := &struct{ Data struct{ Root string } }{}
err = json.Unmarshal(b, jsonr)
if err != nil {
return [32]byte{}, errors.Wrap(err, "error decoding json data from get block root response")
}
rs, err := hexutil.Decode(jsonr.Data.Root)
if err != nil {
return [32]byte{}, errors.Wrap(err, fmt.Sprintf("error decoding hex-encoded value %s", jsonr.Data.Root))
}
return bytesutil.ToBytes32(rs), nil
}
var getForkTpl = idTemplate(getForkForStatePath)
// GetFork queries the Beacon Node API for the Fork from the state identified by stateId.
// Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
// <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
// for the named identifiers.
func (c *Client) GetFork(ctx context.Context, stateId StateOrBlockId) (*ethpb.Fork, error) {
body, err := c.get(ctx, getForkTpl(stateId))
if err != nil {
return nil, errors.Wrapf(err, "error requesting fork by state id = %s", stateId)
}
fr := &forkResponse{}
dataWrapper := &struct{ Data *forkResponse }{Data: fr}
err = json.Unmarshal(body, dataWrapper)
if err != nil {
return nil, errors.Wrap(err, "error decoding json response in GetFork")
}
return fr.Fork()
}
// GetForkSchedule retrieve all forks, past present and future, of which this node is aware.
func (c *Client) GetForkSchedule(ctx context.Context) (forks.OrderedSchedule, error) {
body, err := c.get(ctx, getForkSchedulePath)
if err != nil {
return nil, errors.Wrap(err, "error requesting fork schedule")
}
fsr := &forkScheduleResponse{}
err = json.Unmarshal(body, fsr)
if err != nil {
return nil, err
}
ofs, err := fsr.OrderedForkSchedule()
if err != nil {
return nil, errors.Wrap(err, fmt.Sprintf("problem unmarshaling %s response", getForkSchedulePath))
}
return ofs, nil
}
type NodeVersion struct {
implementation string
semver string
systemInfo string
}
var versionRE = regexp.MustCompile(`^(\w+)\/(v\d+\.\d+\.\d+) \((.*)\)$`)
func parseNodeVersion(v string) (*NodeVersion, error) {
groups := versionRE.FindStringSubmatch(v)
if len(groups) != 4 {
return nil, errors.Wrapf(ErrInvalidNodeVersion, "could not be parsed: %s", v)
}
return &NodeVersion{
implementation: groups[1],
semver: groups[2],
systemInfo: groups[3],
}, nil
}
// GetNodeVersion requests that the beacon node identify information about its implementation in a format
// similar to a HTTP User-Agent field. ex: Lighthouse/v0.1.5 (Linux x86_64)
func (c *Client) GetNodeVersion(ctx context.Context) (*NodeVersion, error) {
b, err := c.get(ctx, getNodeVersionPath)
if err != nil {
return nil, errors.Wrap(err, "error requesting node version")
}
d := struct {
Data struct {
Version string `json:"version"`
} `json:"data"`
}{}
err = json.Unmarshal(b, &d)
if err != nil {
return nil, errors.Wrapf(err, "error unmarshaling response body: %s", string(b))
}
return parseNodeVersion(d.Data.Version)
}
func renderGetStatePath(id StateOrBlockId) string {
return path.Join(getStatePath, string(id))
}
// GetState retrieves the BeaconState for the given state id.
// State identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
// <slot>, <hex encoded stateRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
// for the named identifiers.
// The return value contains the ssz-encoded bytes.
func (c *Client) GetState(ctx context.Context, stateId StateOrBlockId) ([]byte, error) {
statePath := path.Join(getStatePath, string(stateId))
b, err := c.get(ctx, statePath, withSSZEncoding())
if err != nil {
return nil, errors.Wrapf(err, "error requesting state by id = %s", stateId)
}
return b, nil
}
// GetWeakSubjectivity calls a proposed API endpoint that is unique to prysm
// This api method does the following:
// - computes weak subjectivity epoch
// - finds the highest non-skipped block preceding the epoch
// - returns the htr of the found block and returns this + the value of state_root from the block
func (c *Client) GetWeakSubjectivity(ctx context.Context) (*WeakSubjectivityData, error) {
body, err := c.get(ctx, getWeakSubjectivityPath)
if err != nil {
return nil, err
}
v := &apimiddleware.WeakSubjectivityResponse{}
err = json.Unmarshal(body, v)
if err != nil {
return nil, err
}
epoch, err := strconv.ParseUint(v.Data.Checkpoint.Epoch, 10, 64)
if err != nil {
return nil, err
}
blockRoot, err := hexutil.Decode(v.Data.Checkpoint.Root)
if err != nil {
return nil, err
}
stateRoot, err := hexutil.Decode(v.Data.StateRoot)
if err != nil {
return nil, err
}
return &WeakSubjectivityData{
Epoch: types.Epoch(epoch),
BlockRoot: bytesutil.ToBytes32(blockRoot),
StateRoot: bytesutil.ToBytes32(stateRoot),
}, nil
}
// WeakSubjectivityData represents the state root, block root and epoch of the BeaconState + SignedBeaconBlock
// that falls at the beginning of the current weak subjectivity period. These values can be used to construct
// a weak subjectivity checkpoint, or to download a BeaconState+SignedBeaconBlock pair that can be used to bootstrap
// a new Beacon Node using Checkpoint Sync.
type WeakSubjectivityData struct {
BlockRoot [32]byte
StateRoot [32]byte
Epoch types.Epoch
}
func non200Err(response *http.Response) error {
bodyBytes, err := io.ReadAll(response.Body)
var body string
if err != nil {
body = "(Unable to read response body.)"
} else {
body = "response body:\n" + string(bodyBytes)
}
msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
switch response.StatusCode {
case 404:
return errors.Wrap(ErrNotFound, msg)
default:
return errors.Wrap(ErrNotOK, msg)
}
}
type forkResponse struct {
PreviousVersion string `json:"previous_version"`
CurrentVersion string `json:"current_version"`
Epoch string `json:"epoch"`
}
func (f *forkResponse) Fork() (*ethpb.Fork, error) {
epoch, err := strconv.ParseUint(f.Epoch, 10, 64)
if err != nil {
return nil, err
}
cSlice, err := hexutil.Decode(f.CurrentVersion)
if err != nil {
return nil, err
}
if len(cSlice) != 4 {
return nil, fmt.Errorf("got %d byte version for CurrentVersion, expected 4 bytes. hex=%s", len(cSlice), f.CurrentVersion)
}
pSlice, err := hexutil.Decode(f.PreviousVersion)
if err != nil {
return nil, err
}
if len(pSlice) != 4 {
return nil, fmt.Errorf("got %d byte version, expected 4 bytes. version hex=%s", len(pSlice), f.PreviousVersion)
}
return &ethpb.Fork{
CurrentVersion: cSlice,
PreviousVersion: pSlice,
Epoch: types.Epoch(epoch),
}, nil
}
type forkScheduleResponse struct {
Data []forkResponse
}
func (fsr *forkScheduleResponse) OrderedForkSchedule() (forks.OrderedSchedule, error) {
ofs := make(forks.OrderedSchedule, 0)
for _, d := range fsr.Data {
epoch, err := strconv.Atoi(d.Epoch)
if err != nil {
return nil, err
}
vSlice, err := hexutil.Decode(d.CurrentVersion)
if err != nil {
return nil, err
}
if len(vSlice) != 4 {
return nil, fmt.Errorf("got %d byte version, expected 4 bytes. version hex=%s", len(vSlice), d.CurrentVersion)
}
version := bytesutil.ToBytes4(vSlice)
ofs = append(ofs, forks.ForkScheduleEntry{
Version: version,
Epoch: types.Epoch(uint64(epoch)),
})
}
sort.Sort(ofs)
return ofs, nil
}