feat(contests): add contest_submissions table + SubmitToContest action

api/server.go

@@ -545,6 +545,7 @@ func NewApiServer(config config.Config) *ApiServer {
 		g.Get("/events/:eventId/follow-state", app.v1EventFollowState)
 		g.Post("/events/:eventId/follow", app.requireAuthMiddleware, app.requireWriteScope, app.postV1EventFollow)
 		g.Delete("/events/:eventId/follow", app.requireAuthMiddleware, app.requireWriteScope, app.deleteV1EventFollow)
+		g.Post("/events/:eventId/submit", app.requireAuthMiddleware, app.requireWriteScope, app.postV1EventSubmitToContest)
 
 		g.Get("/tracks/:trackId/comments", app.v1TrackComments)
 		g.Get("/tracks/:trackId/comment_count", app.v1TrackCommentCount)

api/v1_events_submit.go

@@ -0,0 +1,79 @@
+package api
+
+import (
+	"encoding/json"
+	"strconv"
+	"time"
+
+	"api.audius.co/indexer"
+	"api.audius.co/trashid"
+	corev1 "github.com/OpenAudio/go-openaudio/pkg/api/core/v1"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/gofiber/fiber/v2"
+	"go.uber.org/zap"
+)
+
+type SubmitToContestBody struct {
+	TrackID string `json:"track_id"`
+}
+
+// postV1EventSubmitToContest enters a track into an open-contest event.
+// Open contests don't have a parent track (unlike remix_contest), so we
+// can't infer the submission from the remixes table — discovery indexes
+// the SubmitToContest action into contest_submissions instead.
+func (app *ApiServer) postV1EventSubmitToContest(c *fiber.Ctx) error {
+	userID := app.getMyId(c)
+	eventID, err := trashid.DecodeHashId(c.Params("eventId"))
+	if err != nil {
+		return fiber.NewError(fiber.StatusBadRequest, "invalid event id")
+	}
+
+	body := SubmitToContestBody{}
+	if err := c.BodyParser(&body); err != nil {
+		return fiber.NewError(fiber.StatusBadRequest, "invalid body")
+	}
+	if body.TrackID == "" {
+		return fiber.NewError(fiber.StatusBadRequest, "track_id is required")
+	}
+	trackID, err := trashid.DecodeHashId(body.TrackID)
+	if err != nil {
+		return fiber.NewError(fiber.StatusBadRequest, "invalid track id")
+	}
+
+	signer, err := app.getApiSigner(c)
+	if err != nil {
+		return err
+	}
+
+	metadata, err := json.Marshal(map[string]any{
+		"track_id": trackID,
+	})
+	if err != nil {
+		return err
+	}
+
+	nonce := time.Now().UnixNano()
+	manageEntityTx := &corev1.ManageEntityLegacy{
+		Signer:     common.HexToAddress(signer.Address).String(),
+		UserId:     int64(userID),
+		EntityId:   int64(eventID),
+		Action:     indexer.Action_SubmitToContest,
+		EntityType: indexer.Entity_Event,
+		Nonce:      strconv.FormatInt(nonce, 10),
+		Metadata:   string(metadata),
+	}
+
+	response, err := app.sendTransactionWithSigner(manageEntityTx, signer.PrivateKey)
+	if err != nil {
+		app.logger.Error("Failed to send SubmitToContest transaction", zap.Error(err))
+		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
+			"error": "Failed to submit to contest",
+		})
+	}
+
+	return c.JSON(fiber.Map{
+		"transaction_hash": response.Msg.GetTransaction().GetHash(),
+		"block_hash":       response.Msg.GetTransaction().GetBlockHash(),
+		"block_number":     response.Msg.GetTransaction().GetHeight(),
+	})
+}

ddl/migrations/0203_contest_submissions.sql

@@ -0,0 +1,24 @@
+begin;
+
+-- Backs the new "open contest" event type, where entries are explicit
+-- submissions (no parent-track remix relationship). Discovery's entity
+-- manager writes a row here when it processes a SubmitToContest action.
+-- The existing remix_contest path keeps using the remixes-table join,
+-- so this table only carries open_contest entries.
+create table if not exists contest_submissions (
+    contest_id integer not null,
+    track_id integer not null,
+    user_id integer not null,
+    created_at timestamp without time zone not null default current_timestamp,
+    primary key (contest_id, track_id)
+);
+
+create index if not exists contest_submissions_track_id_idx
+    on contest_submissions using btree (track_id);
+
+create index if not exists contest_submissions_user_id_idx
+    on contest_submissions using btree (user_id);
+
+comment on table contest_submissions is 'Tracks submitted to an open_contest event. Keyed by (contest_id, track_id); contest_id references events.event_id.';
+
+commit;

indexer/constants.go

@@ -26,6 +26,10 @@ const (
 	Action_React        = "React"
 	Action_Unreact      = "Unreact"
 	Action_Report       = "Report"
+	// Action_SubmitToContest entries a track in an open-contest event.
+	// EntityType is Event, EntityId is the contest event_id, and the
+	// submitted track_id rides on the metadata JSON ({"track_id": <id>}).
+	Action_SubmitToContest = "SubmitToContest"
 )
 
 const (