Add: support delete tag and its references

pkg/api/api.go

@@ -99,6 +99,7 @@ func NewAPI(config Config) (*API, error) {
 	apiMux.HandleFunc("/put_tag_on_file", api.HandlePutTagOnFile)
 	apiMux.HandleFunc("/get_tags_on_file", api.HandleGetTagsOnFile)
 	apiMux.HandleFunc("/delete_tag_on_file", api.HandleDeleteTagOnFile)
+	apiMux.HandleFunc("/delete_tag", api.HandleDeleteTag)
 	// folder
 	apiMux.HandleFunc("/update_foldername", api.HandleUpdateFoldername)
 	// review

pkg/api/handle_tag.go

@@ -125,3 +125,34 @@ func (api *API) HandleUpdateTag(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 }
+
+type DeleteTagRequest struct {
+	ID int64 `json:"id"`
+}
+
+func (api *API) HandleDeleteTag(w http.ResponseWriter, r *http.Request) {
+	// check if user is admin
+	err := api.CheckAdmin(w, r)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	req := &DeleteTagRequest{}
+	err = json.NewDecoder(r.Body).Decode(req)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	err = api.Db.DeleteTag(req.ID)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	log.Println("Successfully deleted tag and its references", req.ID)
+
+	api.HandleOK(w, r)
+}
+

pkg/database/method_tag.go

@@ -60,3 +60,33 @@ func (database *Database) UpdateTag(tag *Tag) (*Tag, error) {
 	}
 	return database.GetTag(tag.ID)
 }
+
+// delete tag and all its references in file_has_tag
+func (database *Database) DeleteTag(id int64) error {
+	// begin transaction
+	tx, err := database.sqlConn.Begin()
+	if err != nil {
+		return err
+	}
+
+	// delete tag
+	_, err = tx.Stmt(database.stmt.deleteTag).Exec(id)
+	if err != nil {
+		tx.Rollback()
+		return err
+	}
+
+	// delete file_has_tag
+	_, err = tx.Stmt(database.stmt.deleteTagReferenceInFileHasTag).Exec(id)
+	if err != nil {
+		tx.Rollback()
+		return err
+	}
+
+	// commit transaction
+	err = tx.Commit()
+	if err != nil {
+		return err
+	}
+	return nil
+}

pkg/database/sql_stmt.go

@@ -205,6 +205,8 @@ var getAnonymousUserQuery = `SELECT id, username, role, avatar_id FROM users WHE
 
 var insertTagQuery = `INSERT INTO tags (name, description, created_by_user_id) VALUES (?, ?, ?);`
 
+var deleteTagQuery = `DELETE FROM tags WHERE id = ?;`
+
 var getTagQuery = `SELECT
 tags.id, tags.name, tags.description,
 users.id, users.username, users.role, users.avatar_id
@@ -231,6 +233,8 @@ WHERE file_has_tag.file_id = ?;`
 
 var deleteTagOnFileQuery = `DELETE FROM file_has_tag WHERE tag_id = ? AND file_id = ?;`
 
+var deleteTagReferenceInFileHasTagQuery = `DELETE FROM file_has_tag WHERE tag_id = ?;`
+
 var updateFoldernameQuery = `UPDATE folders SET foldername = ? WHERE id = ?;`
 
 var insertReviewQuery = `INSERT INTO reviews (user_id, file_id, created_at, content)
@@ -304,12 +308,14 @@ type Stmt struct {
 	updateUserPassword             *sql.Stmt
 	getAnonymousUser               *sql.Stmt
 	insertTag                      *sql.Stmt
+	deleteTag                      *sql.Stmt
 	getTag                         *sql.Stmt
 	getTags                        *sql.Stmt
 	updateTag                      *sql.Stmt
 	putTagOnFile                   *sql.Stmt
 	getTagsOnFile                  *sql.Stmt
 	deleteTagOnFile                *sql.Stmt
+	deleteTagReferenceInFileHasTag *sql.Stmt
 	updateFoldername               *sql.Stmt
 	insertReview                   *sql.Stmt
 	getReviewsOnFile               *sql.Stmt
@@ -621,6 +627,12 @@ func NewPreparedStatement(sqlConn *sql.DB) (*Stmt, error) {
 		return nil, err
 	}
 
+	// init deleteTag
+	stmt.deleteTag, err = sqlConn.Prepare(deleteTagQuery)
+	if err != nil {
+		return nil, err
+	}
+
 	// init getTag
 	stmt.getTag, err = sqlConn.Prepare(getTagQuery)
 	if err != nil {
@@ -657,6 +669,13 @@ func NewPreparedStatement(sqlConn *sql.DB) (*Stmt, error) {
 		return nil, err
 	}
 
+	// init deleteTagReferenceInFileHasTag
+	stmt.deleteTagReferenceInFileHasTag, err = sqlConn.Prepare(
+		deleteTagReferenceInFileHasTagQuery)
+	if err != nil {
+		return nil, err
+	}
+
 	// init updateFoldername
 	stmt.updateFoldername, err = sqlConn.Prepare(updateFoldernameQuery)
 	if err != nil {

web/src/component/EditTag.js

@@ -1,8 +1,10 @@
 import { useState, useEffect } from "react";
-import { useParams } from "react-router";
+import { useParams, useNavigate } from "react-router";
 
 function EditTag() {
   let params = useParams();
+  let navigate = useNavigate();
+
   const [tag, setTag] = useState({
     id: "",
     name: "",
@@ -62,6 +64,27 @@ function EditTag() {
     refreshTagInfo();
   }, []);
 
+  function deleteTag() {
+    fetch("/api/v1/delete_tag", {
+      method: "POST",
+      headers: {
+        "Content-Type": "application/json",
+      },
+      body: JSON.stringify({
+        id: parseInt(params.id),
+      }),
+    })
+      .then((res) => res.json())
+      .then((data) => {
+        if (data.error) {
+          alert(data.error);
+        } else {
+          alert("Tag deleted successfully");
+          navigate(-1);
+        }
+      });
+  }
+
   return (
     <div className="page">
       <h3>Edit Tag</h3>
@@ -107,6 +130,7 @@ function EditTag() {
           value={tag.description}
           onChange={(e) => setTag({ ...tag, description: e.target.value })}
         />
+        <button onClick={deleteTag}>Delete</button>
         <button onClick={() => updateTagInfo()}>Save</button>
       </div>
     </div>