feat(google): group→Google-Group binding model and CRUD API

google/api/api.go

@@ -37,6 +37,10 @@ func InitializeRouter() *gin.Engine {
 
 func InitializeRoutes(router *gin.Engine) {
 	router.GET("/google/ping", Ping)
+
+	router.GET("/google/group-bindings", ListGoogleBindings)
+	router.POST("/google/group-bindings", CreateGoogleBinding)
+	router.DELETE("/google/group-bindings/:bindingID", DeleteGoogleBinding)
 }
 
 // GetClientIP returns the originating client IP, preferring Cloudflare's

google/api/group_binding.go

@@ -0,0 +1,88 @@
+package api
+
+import (
+	"errors"
+	"net/http"
+	"net/mail"
+	"strings"
+
+	"github.com/gaucho-racing/sentinel/google/model"
+	"github.com/gaucho-racing/sentinel/google/service"
+	"github.com/gin-gonic/gin"
+)
+
+// ListGoogleBindings returns all group→Google-Group bindings, optionally
+// filtered to a single group_id. Used by the web UI and by reconciliation.
+func ListGoogleBindings(c *gin.Context) {
+	Require(c, RequestTokenHasScope(c, "sentinel:all"))
+
+	if groupID := c.Query("group_id"); groupID != "" {
+		binding, err := service.GetGoogleBindingForGroup(groupID)
+		if errors.Is(err, service.ErrBindingNotFound) {
+			c.JSON(http.StatusOK, []model.GroupGoogleBinding{})
+			return
+		}
+		if err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+			return
+		}
+		c.JSON(http.StatusOK, []model.GroupGoogleBinding{binding})
+		return
+	}
+
+	bindings, err := service.GetAllGoogleBindings()
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+	c.JSON(http.StatusOK, bindings)
+}
+
+type createGoogleBindingRequest struct {
+	GroupID          string `json:"group_id" binding:"required"`
+	GoogleGroupEmail string `json:"google_group_email" binding:"required"`
+}
+
+func CreateGoogleBinding(c *gin.Context) {
+	Require(c, RequestTokenHasScope(c, "sentinel:all"))
+
+	var req createGoogleBindingRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	email := strings.TrimSpace(req.GoogleGroupEmail)
+	if _, err := mail.ParseAddress(email); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "google_group_email must be a valid email address"})
+		return
+	}
+
+	binding, err := service.CreateGoogleBinding(model.GroupGoogleBinding{
+		GroupID:          req.GroupID,
+		GoogleGroupEmail: email,
+	})
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+	c.JSON(http.StatusOK, binding)
+}
+
+// DeleteGoogleBinding removes a binding by ID. The group_id query param is
+// required to scope the delete — protects against URL tampering that would
+// otherwise let a caller delete a binding for a group they don't control.
+func DeleteGoogleBinding(c *gin.Context) {
+	Require(c, RequestTokenHasScope(c, "sentinel:all"))
+
+	bindingID := c.Param("bindingID")
+	groupID := c.Query("group_id")
+	if groupID == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "group_id query param is required"})
+		return
+	}
+	if err := service.DeleteGoogleBinding(groupID, bindingID); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+	c.Status(http.StatusNoContent)
+}

google/database/db.go

@@ -5,6 +5,7 @@ import (
 	"time"
 
 	"github.com/gaucho-racing/sentinel/google/config"
+	"github.com/gaucho-racing/sentinel/google/model"
 	"github.com/gaucho-racing/sentinel/google/pkg/logger"
 	"gorm.io/driver/postgres"
 	"gorm.io/gorm"
@@ -28,7 +29,10 @@ func Init() {
 		}
 	} else {
 		logger.SugarLogger.Infoln("Connected to database")
-		// Models and AutoMigration are added with the group-binding work.
+		db.AutoMigrate(
+			&model.GroupGoogleBinding{},
+		)
+		logger.SugarLogger.Infoln("AutoMigration complete")
 		DB = db
 	}
 }

google/go.mod

@@ -4,6 +4,7 @@ go 1.25.6
 
 require (
 	github.com/fatih/color v1.19.0
+	github.com/gaucho-racing/ulid-go v1.1.0
 	github.com/gin-contrib/cors v1.7.7
 	github.com/gin-gonic/gin v1.12.0
 	github.com/go-resty/resty/v2 v2.17.2

google/go.sum

@@ -13,6 +13,8 @@ github.com/fatih/color v1.19.0 h1:Zp3PiM21/9Ld6FzSKyL5c/BULoe/ONr9KlbYVOfG8+w=
 github.com/fatih/color v1.19.0/go.mod h1:zNk67I0ZUT1bEGsSGyCZYZNrHuTkJJB+r6Q9VuMi0LE=
 github.com/gabriel-vasile/mimetype v1.4.12 h1:e9hWvmLYvtp846tLHam2o++qitpguFiYCKbn0w9jyqw=
 github.com/gabriel-vasile/mimetype v1.4.12/go.mod h1:d+9Oxyo1wTzWdyVUPMmXFvp4F9tea18J8ufA774AB3s=
+github.com/gaucho-racing/ulid-go v1.1.0 h1:x00XM8EjlegfhlLYIob+U8ba5iX0gDRUr8mgBsjCunk=
+github.com/gaucho-racing/ulid-go v1.1.0/go.mod h1:HwqoC27UtvXHrmhTO7K2GnXZ1VAeR6tg6EjrSEP5JUU=
 github.com/gin-contrib/cors v1.7.7 h1:Oh9joP463x7Mw72vhvJ61YQm8ODh9b04YR7vsOErD0Q=
 github.com/gin-contrib/cors v1.7.7/go.mod h1:K5tW0RkzJtWSiOdikXloy8VEZlgdVNpHNw8FpjUPNrE=
 github.com/gin-contrib/sse v1.1.0 h1:n0w2GMuUpWDVp7qSpvze6fAu9iRxJY4Hmj6AmBOU05w=

google/model/group_binding.go

@@ -0,0 +1,22 @@
+package model
+
+import "time"
+
+// GroupGoogleBinding maps a Sentinel group to the Google Group its membership
+// is mirrored into. The relationship is 1:1 — one Sentinel group projects onto
+// one Google Group, and a given Google Group is driven by a single Sentinel
+// group — so both columns are unique.
+//
+// Owned by the google service: bindings are an integration-side concept that
+// reference Sentinel group IDs from core but live in google's domain. Sync is
+// one-way (Sentinel -> Google); this row only records where to project.
+type GroupGoogleBinding struct {
+	ID               string    `json:"id" gorm:"primaryKey"`
+	GroupID          string    `json:"group_id" gorm:"uniqueIndex"`
+	GoogleGroupEmail string    `json:"google_group_email" gorm:"uniqueIndex"`
+	CreatedAt        time.Time `json:"created_at" gorm:"autoCreateTime"`
+}
+
+func (GroupGoogleBinding) TableName() string {
+	return "group_google_binding"
+}

google/service/group_binding.go

@@ -0,0 +1,53 @@
+package service
+
+import (
+	"errors"
+
+	"github.com/gaucho-racing/sentinel/google/database"
+	"github.com/gaucho-racing/sentinel/google/model"
+	"github.com/gaucho-racing/ulid-go"
+	"gorm.io/gorm"
+)
+
+var ErrBindingNotFound = errors.New("group google binding not found")
+
+func GetAllGoogleBindings() ([]model.GroupGoogleBinding, error) {
+	bindings := []model.GroupGoogleBinding{}
+	if err := database.DB.Find(&bindings).Error; err != nil {
+		return []model.GroupGoogleBinding{}, err
+	}
+	return bindings, nil
+}
+
+// GetGoogleBindingForGroup returns the binding for a group, or
+// ErrBindingNotFound if the group has none. The 1:1 model means at most one
+// row per group.
+func GetGoogleBindingForGroup(groupID string) (model.GroupGoogleBinding, error) {
+	var binding model.GroupGoogleBinding
+	if err := database.DB.Where("group_id = ?", groupID).First(&binding).Error; err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return model.GroupGoogleBinding{}, ErrBindingNotFound
+		}
+		return model.GroupGoogleBinding{}, err
+	}
+	return binding, nil
+}
+
+func CreateGoogleBinding(binding model.GroupGoogleBinding) (model.GroupGoogleBinding, error) {
+	if binding.ID == "" {
+		binding.ID = ulid.Make().Prefixed("ggb")
+	}
+	if err := database.DB.Create(&binding).Error; err != nil {
+		return model.GroupGoogleBinding{}, err
+	}
+	return binding, nil
+}
+
+// DeleteGoogleBinding scopes the delete to (groupID, bindingID) so a tampered
+// request can't drop a binding for a different group.
+func DeleteGoogleBinding(groupID, bindingID string) error {
+	if err := database.DB.Where("group_id = ? AND id = ?", groupID, bindingID).Delete(&model.GroupGoogleBinding{}).Error; err != nil {
+		return err
+	}
+	return nil
+}