Add event join service and api endpoint

Signed-off-by: Asai Neko <sugar@sne.moe>

api/event/join.go

@@ -0,0 +1,70 @@
+package event
+
+import (
+	"nixcn-cms/internal/exception"
+	"nixcn-cms/service/service_event"
+	"nixcn-cms/utils"
+
+	"github.com/gin-gonic/gin"
+)
+
+// Join handles the request for a user to join a specific event.
+//
+//	@Summary		Join an Event
+//	@Description	Allows an authenticated user to join an event by providing the event ID. The user's role and state are initialized by the service.
+//	@Tags			Event
+//	@Accept			json
+//	@Produce		json
+//	@Param			request	body		service_event.EventJoinData	true	"Event Join Details (UserId and EventId are required)"
+//	@Success		200		{object}	utils.RespStatus{data=nil}	"Successfully joined the event"
+//	@Failure		400		{object}	utils.RespStatus{data=nil}	"Invalid Input or UUID Parse Failed"
+//	@Failure		403		{object}	utils.RespStatus{data=nil}	"Unauthorized / Missing User ID"
+//	@Failure		500		{object}	utils.RespStatus{data=nil}	"Internal Server Error / Database Error"
+//	@Security		ApiKeyAuth
+//	@Router			/event/join [post]
+func (self *EventHandler) Join(c *gin.Context) {
+	userIdOrig, ok := c.Get("user_id")
+	if !ok {
+		errorCode := new(exception.Builder).
+			SetStatus(exception.StatusUser).
+			SetService(exception.ServiceEvent).
+			SetEndpoint(exception.EndpointEventServiceJoin).
+			SetType(exception.TypeCommon).
+			SetOriginal(exception.CommonErrorMissingUserId).
+			Throw(c).
+			String()
+		utils.HttpResponse(c, 403, errorCode)
+		return
+	}
+
+	var joinData service_event.EventJoinData
+	if err := c.ShouldBindJSON(&joinData); err != nil {
+		errorCode := new(exception.Builder).
+			SetStatus(exception.StatusUser).
+			SetService(exception.ServiceEvent).
+			SetEndpoint(exception.EndpointEventServiceJoin).
+			SetType(exception.TypeCommon).
+			SetOriginal(exception.CommonErrorInvalidInput).
+			SetError(err).
+			Throw(c).
+			String()
+		utils.HttpResponse(c, 400, errorCode)
+		return
+	}
+
+	joinData.UserId = userIdOrig.(string)
+
+	payload := &service_event.EventJoinPayload{
+		Context: c,
+		Data:    &joinData,
+	}
+
+	result := self.svc.JoinEvent(payload)
+
+	if result.Common.Exception.Original != exception.CommonSuccess {
+		utils.HttpResponse(c, result.Common.HttpCode, result.Common.Exception.String())
+		return
+	}
+
+	utils.HttpResponse(c, result.Common.HttpCode, result.Common.Exception.String())
+}