API: Add participation key generation endpoint to algod API

cmd/algokey/part.go

@@ -19,7 +19,6 @@ package main
 import (
 	"encoding/base64"
 	"fmt"
-	"math"
 	"os"
 
 	"github.com/spf13/cobra"
@@ -58,7 +57,7 @@ var partGenerateCmd = &cobra.Command{
 		}
 
 		if partKeyDilution == 0 {
-			partKeyDilution = 1 + uint64(math.Sqrt(float64(partLastRound-partFirstRound)))
+			partKeyDilution = account.DefaultKeyDilution(basics.Round(partFirstRound), basics.Round(partLastRound))
 		}
 
 		var err error

daemon/algod/api/algod.oas2.json

@@ -979,7 +979,7 @@
         ],
         "responses": {
           "200": {
-            "description": "The current swagger spec",
+            "description": "An empty JSON object is returned if the generation process was started. Currently no status is available.",
             "schema": {
               "type": "string"
             }
@@ -996,12 +996,6 @@
               "$ref": "#/definitions/ErrorResponse"
             }
           },
-          "404": {
-            "description": "Participation Key Not Found",
-            "schema": {
-              "$ref": "#/definitions/ErrorResponse"
-            }
-          },
           "500": {
             "description": "Internal Error",
             "schema": {

daemon/algod/api/algod.oas3.yml

@@ -5428,7 +5428,7 @@
                 }
               }
             },
-            "description": "The current swagger spec"
+            "description": "An empty JSON object is returned if the generation process was started. Currently no status is available."
           },
           "400": {
             "content": {
@@ -5450,16 +5450,6 @@
             },
             "description": "Invalid API Token"
           },
-          "404": {
-            "content": {
-              "application/json": {
-                "schema": {
-                  "$ref": "#/components/schemas/ErrorResponse"
-                }
-              }
-            },
-            "description": "Participation Key Not Found"
-          },
           "500": {
             "content": {
               "application/json": {

daemon/algod/api/server/router.go

@@ -19,6 +19,7 @@ package server
 
 import (
 	"fmt"
+	"golang.org/x/sync/semaphore"
 	"net"
 	"net/http"
 
@@ -119,9 +120,10 @@ func NewRouter(logger logging.Logger, node APINodeInterface, shutdown <-chan str
 
 	// Registering v2 routes
 	v2Handler := v2.Handlers{
-		Node:     node,
-		Log:      logger,
-		Shutdown: shutdown,
+		Node:          node,
+		Log:           logger,
+		Shutdown:      shutdown,
+		KeygenLimiter: semaphore.NewWeighted(1),
 	}
 	nppublic.RegisterHandlers(e, &v2Handler, publicMiddleware...)
 	npprivate.RegisterHandlers(e, &v2Handler, adminMiddleware...)

daemon/algod/api/server/v2/handlers.go

@@ -22,6 +22,7 @@ import (
 	"encoding/base64"
 	"errors"
 	"fmt"
+	"golang.org/x/sync/semaphore"
 	"io"
 	"math"
 	"net/http"
@@ -73,11 +74,10 @@ var WaitForBlockTimeout = 1 * time.Minute
 
 // Handlers is an implementation to the V2 route handler interface defined by the generated code.
 type Handlers struct {
-	Node     NodeInterface
-	Log      logging.Logger
-	Shutdown <-chan struct{}
-	// Keygen is used to limit the number of concurrent key generation requests.
-	Keygen chan struct{}
+	Node          NodeInterface
+	Log           logging.Logger
+	Shutdown      <-chan struct{}
+	KeygenLimiter *semaphore.Weighted
 }
 
 // LedgerForAPI describes the Ledger methods used by the v2 API.
@@ -267,22 +267,15 @@ func (v2 *Handlers) generateKeyHandler(address string, params model.GeneratePart
 // GenerateParticipationKeys generates and installs participation keys to the node.
 // (POST /v2/participation/generate/{address})
 func (v2 *Handlers) GenerateParticipationKeys(ctx echo.Context, address string, params model.GenerateParticipationKeysParams) error {
-	if v2.Keygen == nil {
-		v2.Keygen = make(chan struct{}, 1)
-	}
-
-	select {
-	case v2.Keygen <- struct{}{}:
+	if v2.KeygenLimiter != nil && v2.KeygenLimiter.TryAcquire(1) {
 		go func() {
-			defer func() {
-				<-v2.Keygen
-			}()
+			defer v2.KeygenLimiter.Release(1)
 			err := v2.generateKeyHandler(address, params)
 			if err != nil {
 				v2.Log.Warnf("Error generating participation keys: %v", err)
 			}
 		}()
-	default:
+	} else {
 		err := fmt.Errorf("participation key generation already in progress")
 		return badRequest(ctx, err, err.Error(), v2.Log)
 	}

daemon/algod/api/server/v2/test/handlers_test.go

@@ -22,6 +22,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"golang.org/x/sync/semaphore"
 	"io"
 	"math"
 	"net"
@@ -2390,7 +2391,12 @@ func TestGeneratePartkeys(t *testing.T) {
 	defer releasefunc()
 	dummyShutdownChan := make(chan struct{})
 	mockNode := makeMockNode(mockLedger, t.Name(), nil, cannedStatusReportGolden, false)
-	handler := v2.Handlers{Node: mockNode, Log: logging.Base(), Shutdown: dummyShutdownChan}
+	handler := v2.Handlers{
+		Node:          mockNode,
+		Log:           logging.Base(),
+		Shutdown:      dummyShutdownChan,
+		KeygenLimiter: semaphore.NewWeighted(1),
+	}
 	e := echo.New()
 
 	var addr basics.Address
@@ -2411,18 +2417,20 @@ func TestGeneratePartkeys(t *testing.T) {
 		assert.Equal(t, http.StatusOK, rec.Code)
 
 		// Wait for keygen to complete
-		handler.Keygen <- struct{}{}
+		err = handler.KeygenLimiter.Acquire(context.Background(), 1)
+		require.NoError(t, err)
 		require.Greater(t, len(mockNode.PartKeyBinary), 0)
-		<-handler.Keygen
+		handler.KeygenLimiter.Release(1)
 	}
 
 	{
 		req := httptest.NewRequest(http.MethodPost, "/", nil)
 		rec := httptest.NewRecorder()
 		c := e.NewContext(req, rec)
 		// Simulate a blocked keygen process (and block until the previous keygen is complete)
-		handler.Keygen <- struct{}{}
-		err := handler.GenerateParticipationKeys(c, addr.String(), model.GenerateParticipationKeysParams{
+		err := handler.KeygenLimiter.Acquire(context.Background(), 1)
+		require.NoError(t, err)
+		err = handler.GenerateParticipationKeys(c, addr.String(), model.GenerateParticipationKeysParams{
 			First: 1000,
 			Last:  2000,
 		})

data/account/participation.go

@@ -216,7 +216,7 @@ func (part PersistedParticipation) PersistNewParent() error {
 	})
 }
 
-// DefaultKeyDilution computes the default dilution based on first and last rounds.
+// DefaultKeyDilution computes the default dilution based on first and last rounds as the sqrt of validity window.
 func DefaultKeyDilution(first, last basics.Round) uint64 {
 	return 1 + uint64(math.Sqrt(float64(last-first)))
 }

data/account/participationRegistry_test.go

@@ -23,7 +23,6 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
-	"math"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -99,7 +98,7 @@ func makeTestParticipationWithLifetime(a *require.Assertions, addrID int, first,
 
 	// Generate part keys like in partGenerateCmd and FillDBWithParticipationKeys
 	if dilution == 0 {
-		dilution = 1 + uint64(math.Sqrt(float64(last-first)))
+		dilution = DefaultKeyDilution(first, last)
 	}
 
 	// Compute how many distinct participation keys we should generate

go.mod

@@ -42,6 +42,7 @@ require (
 	github.com/stretchr/testify v1.8.4
 	golang.org/x/crypto v0.14.0
 	golang.org/x/exp v0.0.0-20230713183714-613f0c0eb8a1
+	golang.org/x/sync v0.3.0
 	golang.org/x/sys v0.13.0
 	golang.org/x/text v0.13.0
 	gopkg.in/sohlich/elogrus.v3 v3.0.0-20180410122755-1fa29e2f2009
@@ -155,7 +156,6 @@ require (
 	go.uber.org/zap v1.24.0 // indirect
 	golang.org/x/mod v0.12.0 // indirect
 	golang.org/x/net v0.17.0 // indirect
-	golang.org/x/sync v0.3.0 // indirect
 	golang.org/x/term v0.13.0 // indirect
 	golang.org/x/time v0.0.0-20201208040808-7e3f01d25324 // indirect
 	golang.org/x/tools v0.11.0 // indirect

libgoal/participation/participation.go

@@ -40,7 +40,10 @@ func participationKeysPath(dataDir string, address basics.Address, firstValid, l
 // directory is empty, the key will be installed.
 func GenParticipationKeysTo(address string, firstValid, lastValid, keyDilution uint64, outDir string, installFunc func(keyPath string) error) (part account.Participation, filePath string, err error) {
 
-	install := outDir == "" && installFunc != nil
+	install := outDir == ""
+	if install && installFunc == nil {
+		return account.Participation{}, "", fmt.Errorf("must provide an install function when installing keys")
+	}
 
 	// Parse the address
 	parsedAddr, err := basics.UnmarshalChecksumAddress(address)

libgoal/participation/participation_test.go

@@ -103,3 +103,11 @@ func TestGenParticipationKeysTo_DefaultKeyDilution(t *testing.T) {
 		})
 	}
 }
+
+func TestBadInput(t *testing.T) {
+	partitiontest.PartitionTest(t)
+	t.Parallel()
+
+	_, _, err := GenParticipationKeysTo("", 0, 0, 0, "", nil)
+	require.ErrorContains(t, err, "must provide an install function when installing keys")
+}

test/e2e-go/features/participation/accountParticipationTransitions_test.go

@@ -21,6 +21,7 @@ package participation
 // deterministic.
 
 import (
+	"errors"
 	"fmt"
 	"path/filepath"
 	"testing"
@@ -41,8 +42,7 @@ import (
 func installParticipationKey(t *testing.T, client libgoal.Client, addr string, firstValid, lastValid uint64) (resp model.PostParticipationResponse, part account.Participation, err error) {
 	// Install overlapping participation keys...
 	installFunc := func(keyPath string) error {
-		_, err := client.AddParticipationKey(keyPath)
-		return err
+		return errors.New("the install directory is provided, so keys should not be installed")
 	}
 	part, filePath, err := participation.GenParticipationKeysTo(addr, firstValid, lastValid, 100, t.TempDir(), installFunc)
 	require.NoError(t, err)

test/e2e-go/features/stateproofs/stateproofs_test.go

@@ -18,6 +18,7 @@ package stateproofs
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -679,8 +680,7 @@ func installParticipationKey(t *testing.T, client libgoal.Client, addr string, f
 
 	// Install overlapping participation keys...
 	installFunc := func(keyPath string) error {
-		_, err := client.AddParticipationKey(keyPath)
-		return err
+		return errors.New("the install directory is provided, so keys should not be installed")
 	}
 	part, filePath, err := participation.GenParticipationKeysTo(addr, firstValid, lastValid, 100, dir, installFunc)
 	require.NoError(t, err)

test/e2e-go/features/transactions/onlineStatusChange_test.go

@@ -17,6 +17,7 @@
 package transactions
 
 import (
+	"errors"
 	"fmt"
 	"path/filepath"
 	"testing"
@@ -173,8 +174,7 @@ func TestCloseOnError(t *testing.T) {
 
 	var partkeyFile string
 	installFunc := func(keyPath string) error {
-		_, err := client.AddParticipationKey(keyPath)
-		return err
+		return errors.New("the install directory is provided, so keys should not be installed")
 	}
 	_, partkeyFile, err = participation.GenParticipationKeysTo(initiallyOffline, 0, curRound+1000, 0, t.TempDir(), installFunc)
 	a.NoError(err)