query with aggregate in mongodb and go (match, lookup) - mongodb

Question

I need that when passing a search parameter I can obtain the subcategories with the categories, also obtain the total data of all the subcategories. I don't know if it can be done with bson.M. I leave my code.
This function is the one I use for categories, I used it for subcategories but adding $lookup to bson.M throws an error.
func SubcategoriesGet(c *fiber.Ctx) error {
categoryCollection := config.MI.DB.Collection("subcategories")
ctx, _ := context.WithTimeout(context.Background(), 10*time.Second)
var categories []models.Category
filter := bson.M{}
findOptions := options.Find()
if s := c.Query("s"); s != "" {
filter = bson.M{
"$or": []bson.M{
{
"name": bson.M{
"$regex": primitive.Regex{
Pattern: s,
Options: "i",
},
},
},
// {
// "visible": bson.M{
// "$regex": primitive.Regex{
// Pattern: s,
// Options: "i",
// },
// },
// },
},
}
}
if visible := c.Query("visible"); visible == "1" {
filter = bson.M{"visible": true}
}
if visible := c.Query("visible"); visible == "0" {
filter = bson.M{"visible": false}
}
page, _ := strconv.Atoi(c.Query("page", "1"))
limitVal, _ := strconv.Atoi(c.Query("limit", "10"))
var limit int64 = int64(limitVal)
total, _ := categoryCollection.CountDocuments(ctx, filter)
findOptions.SetSort(bson.M{"_id": -1})
findOptions.SetSkip((int64(page) - 1) * limit)
findOptions.SetLimit(limit)
// findOptions.
cursor, err := categoryCollection.Find(ctx, filter, findOptions)
defer cursor.Close(ctx)
if err != nil {
return c.Status(fiber.StatusNotFound).JSON(fiber.Map{
"success": false,
"message": "Users not found",
"error": err,
})
}
for cursor.Next(ctx) {
var category models.Category
cursor.Decode(&category)
categories = append(categories, category)
}
last := math.Ceil(float64(total / limit))
if last < 1 && total > 0 {
last = 1
}
return c.Status(fiber.StatusOK).JSON(fiber.Map{
"data": categories,
"total": total,
"page": page,
"last_page": last,
"limit": limit,
})
}
and this is the code that advances, I only need to obtain the total number of documents and be able to do a search by subcategory name.
func SubcategoriesGet(c *fiber.Ctx) error {
subcategoryCollection := config.MI.DB.Collection("subcategories")
ctx, _ := context.WithTimeout(context.Background(), 10*time.Second)
var subcategory []models.Subategory
// querys
page, _ := strconv.Atoi(c.Query("page", "1")) // page
limitVal, _ := strconv.Atoi(c.Query("limit", "10")) // limit
var limit int64 = int64(limitVal)
// matchState := bson.D{}
if s := c.Query("s"); s != "" {
// bson.D{{"$regexMatch", bson.D{{"input", "$name"}, {"regex", "/g/"}}}}
// matchState = bson.M{"$match": bson.M{"wordname": bson.M{"$in": []bson.RegEx{{"^how$", "i"}}}}}
}
// pipeline
lookupState := bson.D{{"$lookup", bson.D{{"from", "categories"}, {"localField", "idcategory"}, {"foreignField", "_id"}, {"as", "category"}}}}
unwindState := bson.D{{"$unwind", bson.D{{"path", "$category"}, {"preserveNullAndEmptyArrays", false}}}}
limitState := bson.D{{"$limit", limit}}
sortState := bson.D{{"$sort", bson.D{{"_id", -1}}}}
skipState := bson.D{{"$skip", (int64(page) - 1) * limit}}
// groupState := bson.D{{"$project", bson.D{{"_id", 1}, {"name", 1}, {"category.name", 1}}}}
// orState := bson.D{{"$or", bson.D{{"name", bson.D{{"$regex", primitive.Regex{Pattern: "gec", Options: "i"}}}}}}}
// groupState := bson.D{{"$group", bson.D{{"_id", "$_id"}}}}
// countState := bson.D{{"$count", "total"}}
cursor, err := subcategoryCollection.Aggregate(ctx, mongo.Pipeline{skipState, lookupState, unwindState, limitState, sortState})
if err != nil {
panic(err)
}
// cursorTotal, err := subcategoryCollection.Aggregate(ctx, mongo.Pipeline{lookupState, unwindState, limitState, sortState})
// if err != nil {
// panic(err)
// }
// var showData []bson.M
// if err = cursor.Decode(); err != nil {
// panic(err)
// }
for cursor.Next(ctx) {
var subc models.Subategory
cursor.Decode(&subc)
subcategory = append(subcategory, subc)
}
return c.Status(fiber.StatusOK).JSON(fiber.Map{
"data": subcategory,
// "total": ,
"page": page,
// "last_page": last,
"limit": limit,
})
}
I did tests with aggregate ($lookup, $skip, $limit, $count) etc. I still need to do a LIKE in SQL search and get the total number of documents