exp: Add the Zenith (Light Horizon) prototype

exp/lighthorizon/Dockerfile

@@ -0,0 +1,25 @@
+FROM golang:1.17 AS builder
+
+WORKDIR /go/src/github.com/stellar/go
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . ./
+# RUN go install github.com/stellar/go/exp/lighthorizon
+# RUN go install github.com/stellar/go/exp/lighthorizon/index/cmd/batch/map
+RUN go install github.com/stellar/go/exp/lighthorizon/index/cmd/batch/reduce
+# RUN go install github.com/stellar/go/exp/lighthorizon/index/cmd/single
+
+FROM ubuntu:20.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+# ca-certificates are required to make tls connections
+RUN apt-get update && apt-get install -y --no-install-recommends ca-certificates curl wget gnupg apt-utils
+RUN apt-get clean
+
+# COPY --from=builder /go/bin/lighthorizon ./
+# COPY --from=builder /go/bin/map ./
+COPY --from=builder /go/bin/reduce ./
+# COPY --from=builder /go/bin/single ./
+
+ENTRYPOINT ["./reduce"]
+

exp/lighthorizon/actions/operation.go

@@ -0,0 +1,127 @@
+package actions
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strconv"
+
+	"github.com/stellar/go/exp/lighthorizon/adapters"
+	"github.com/stellar/go/exp/lighthorizon/archive"
+	"github.com/stellar/go/exp/lighthorizon/index"
+	"github.com/stellar/go/protocols/horizon/operations"
+	"github.com/stellar/go/support/render/hal"
+	"github.com/stellar/go/toid"
+)
+
+func Operations(archiveWrapper archive.Wrapper, indexStore index.Store) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// For _links rendering, imitate horizon.stellar.org links for horizon-cmp
+		r.URL.Scheme = "http"
+		r.URL.Host = "localhost:8080"
+
+		if r.Method != "GET" {
+			return
+		}
+
+		query, err := url.ParseQuery(r.URL.RawQuery)
+		if err != nil {
+			fmt.Fprintf(w, "Error: %v", err)
+			return
+		}
+
+		var cursor int64
+		if query.Get("cursor") == "" {
+			cursor = toid.New(1, 1, 1).ToInt64()
+		} else {
+			cursor, err = strconv.ParseInt(query.Get("cursor"), 10, 64)
+			if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+		}
+
+		var limit int64
+		if query.Get("limit") == "" {
+			limit = 10
+		} else {
+			limit, err = strconv.ParseInt(query.Get("limit"), 10, 64)
+			if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+		}
+
+		if limit == 0 || limit > 200 {
+			limit = 10
+		}
+
+		page := hal.Page{
+			Cursor: query.Get("cursor"),
+			Order:  "asc",
+			Limit:  uint64(limit),
+		}
+		page.Init()
+		page.FullURL = r.URL
+
+		// For now, use a query param for now to avoid dragging in chi-router. Not
+		// really the point of the experiment yet.
+		account := query.Get("account")
+		if account != "" {
+			// Skip the cursor ahead to the next active checkpoint for this account
+			checkpoint, err := indexStore.NextActive(account, "all_all", uint32(toid.Parse(cursor).LedgerSequence/64))
+			if err == io.EOF {
+				// never active. No results.
+				page.PopulateLinks()
+
+				encoder := json.NewEncoder(w)
+				encoder.SetIndent("", "  ")
+				err = encoder.Encode(page)
+				if err != nil {
+					fmt.Fprintf(w, "Error: %v", err)
+					return
+				}
+				return
+			} else if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+			ledger := int32(checkpoint * 64)
+			if ledger < 0 {
+				// Check we don't overflow going from uint32 -> int32
+				fmt.Fprintf(w, "Error: Ledger overflow")
+				return
+			}
+			cursor = toid.New(ledger, 1, 1).ToInt64()
+		}
+
+		ops, err := archiveWrapper.GetOperations(cursor, limit)
+		if err != nil {
+			fmt.Fprintf(w, "Error: %v", err)
+			return
+		}
+
+		for _, op := range ops {
+			var response operations.Operation
+			response, err = adapters.PopulateOperation(r, &op)
+			if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+
+			page.Add(response)
+		}
+
+		page.PopulateLinks()
+
+		encoder := json.NewEncoder(w)
+		encoder.SetIndent("", "  ")
+		err = encoder.Encode(page)
+		if err != nil {
+			fmt.Fprintf(w, "Error: %v", err)
+			return
+		}
+	}
+}

exp/lighthorizon/actions/transaction.go

@@ -0,0 +1,110 @@
+package actions
+
+import (
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+
+	"github.com/stellar/go/exp/lighthorizon/adapters"
+	"github.com/stellar/go/exp/lighthorizon/archive"
+	"github.com/stellar/go/exp/lighthorizon/index"
+	hProtocol "github.com/stellar/go/protocols/horizon"
+	"github.com/stellar/go/support/render/hal"
+)
+
+func Transactions(archiveWrapper archive.Wrapper, indexStore index.Store) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// For _links rendering, imitate horizon.stellar.org links for horizon-cmp
+		r.URL.Scheme = "http"
+		r.URL.Host = "localhost:8080"
+
+		if r.Method != "GET" {
+			return
+		}
+
+		query, err := url.ParseQuery(r.URL.RawQuery)
+		if err != nil {
+			fmt.Fprintf(w, "Error: %v", err)
+			return
+		}
+
+		page := hal.Page{}
+		page.Init()
+		page.FullURL = r.URL
+
+		// For now, use a query param for now to avoid dragging in chi-router. Not
+		// really the point of the experiment yet.
+		id := query.Get("id")
+		var cursor int64
+		if id != "" {
+			b, err := hex.DecodeString(id)
+			if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+			if len(b) != 32 {
+				fmt.Fprintf(w, "Error: invalid hash")
+				return
+			}
+			var hash [32]byte
+			copy(hash[:], b)
+			// Skip the cursor ahead to the next active checkpoint for this account
+			txnToid, err := indexStore.TransactionTOID(hash)
+			if err == io.EOF {
+				// never active. No results.
+				page.PopulateLinks()
+
+				encoder := json.NewEncoder(w)
+				encoder.SetIndent("", "  ")
+				err = encoder.Encode(page)
+				if err != nil {
+					fmt.Fprintf(w, "Error: %v", err)
+					return
+				}
+				return
+			} else if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+			cursor = txnToid
+		}
+
+		txns, err := archiveWrapper.GetTransactions(cursor, 1)
+		if err != nil {
+			fmt.Fprintf(w, "Error: %v", err)
+			return
+		}
+
+		for _, txn := range txns {
+			hash, err := txn.TransactionHash()
+			if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+			if id != "" && hash != id {
+				continue
+			}
+			var response hProtocol.Transaction
+			response, err = adapters.PopulateTransaction(r, &txn)
+			if err != nil {
+				fmt.Fprintf(w, "Error: %v", err)
+				return
+			}
+
+			page.Add(response)
+		}
+
+		page.PopulateLinks()
+
+		encoder := json.NewEncoder(w)
+		encoder.SetIndent("", "  ")
+		err = encoder.Encode(page)
+		if err != nil {
+			fmt.Fprintf(w, "Error: %v", err)
+			return
+		}
+	}
+}

exp/lighthorizon/adapters/account_merge.go

@@ -0,0 +1,21 @@
+package adapters
+
+import (
+	"github.com/stellar/go/exp/lighthorizon/common"
+	"github.com/stellar/go/protocols/horizon/operations"
+)
+
+func populateAccountMergeOperation(op *common.Operation, baseOp operations.Base) (operations.AccountMerge, error) {
+	destination := op.Get().Body.MustDestination()
+
+	return operations.AccountMerge{
+		Base:    baseOp,
+		Account: op.SourceAccount().Address(),
+		Into:    destination.Address(),
+		// TODO:
+		AccountMuxed:   "",
+		AccountMuxedID: 0,
+		IntoMuxed:      "",
+		IntoMuxedID:    0,
+	}, nil
+}

exp/lighthorizon/adapters/allow_trust.go

@@ -0,0 +1,43 @@
+package adapters
+
+import (
+	"github.com/stellar/go/exp/lighthorizon/common"
+	"github.com/stellar/go/protocols/horizon/base"
+	"github.com/stellar/go/protocols/horizon/operations"
+	"github.com/stellar/go/support/errors"
+	"github.com/stellar/go/xdr"
+)
+
+func populateAllowTrustOperation(op *common.Operation, baseOp operations.Base) (operations.AllowTrust, error) {
+	allowTrust := op.Get().Body.MustAllowTrustOp()
+
+	var (
+		assetType string
+		code      string
+		issuer    string
+	)
+
+	err := allowTrust.Asset.ToAsset(op.SourceAccount()).Extract(&assetType, &code, &issuer)
+	if err != nil {
+		return operations.AllowTrust{}, errors.Wrap(err, "xdr.Asset.Extract error")
+	}
+
+	flags := xdr.TrustLineFlags(allowTrust.Authorize)
+
+	return operations.AllowTrust{
+		Base: baseOp,
+		Asset: base.Asset{
+			Type:   assetType,
+			Code:   code,
+			Issuer: issuer,
+		},
+
+		Trustee:                        op.SourceAccount().Address(),
+		Trustor:                        allowTrust.Trustor.Address(),
+		Authorize:                      flags.IsAuthorized(),
+		AuthorizeToMaintainLiabilities: flags.IsAuthorizedToMaintainLiabilitiesFlag(),
+		// TODO:
+		TrusteeMuxed:   "",
+		TrusteeMuxedID: 0,
+	}, nil
+}

exp/lighthorizon/adapters/begin_sponsoring_future_reserves.go

@@ -0,0 +1,15 @@
+package adapters
+
+import (
+	"github.com/stellar/go/exp/lighthorizon/common"
+	"github.com/stellar/go/protocols/horizon/operations"
+)
+
+func populateBeginSponsoringFutureReservesOperation(op *common.Operation, baseOp operations.Base) (operations.BeginSponsoringFutureReserves, error) {
+	beginSponsoringFutureReserves := op.Get().Body.MustBeginSponsoringFutureReservesOp()
+
+	return operations.BeginSponsoringFutureReserves{
+		Base:        baseOp,
+		SponsoredID: beginSponsoringFutureReserves.SponsoredId.Address(),
+	}, nil
+}

exp/lighthorizon/adapters/bump_sequence.go

@@ -0,0 +1,17 @@
+package adapters
+
+import (
+	"strconv"
+
+	"github.com/stellar/go/exp/lighthorizon/common"
+	"github.com/stellar/go/protocols/horizon/operations"
+)
+
+func populateBumpSequenceOperation(op *common.Operation, baseOp operations.Base) (operations.BumpSequence, error) {
+	bumpSequence := op.Get().Body.MustBumpSequenceOp()
+
+	return operations.BumpSequence{
+		Base:   baseOp,
+		BumpTo: strconv.FormatInt(int64(bumpSequence.BumpTo), 10),
+	}, nil
+}