Delete note api

databaseutil/databaseutil.go

@@ -94,6 +94,76 @@ func GetPasswordForUserWithEmailAddress(emailAddress string) ([]byte, error) {
 	return password, nil
 }
 
+type NoteData struct {
+	Id           int64
+	AuthorId     int64
+	Content      string
+	CreationTime time.Time
+}
+
+func returnNotes(rows *sql.Rows) ([]*NoteData, error) {
+	var notes []*NoteData = make([]*NoteData, 0, 10)
+
+	for rows.Next() {
+		note := &NoteData{}
+		if err := rows.Scan(&note.Id, &note.AuthorId, &note.Content, &note.CreationTime); err != nil {
+			return nil, err
+		}
+
+		notes = append(notes, note)
+	}
+
+	return notes, nil
+}
+
+func GetNote(id int64) (*NoteData, error) {
+
+	sqlQuery := `
+		SELECT id, author_id, content, creation_time FROM note
+		WHERE id = $1`
+
+	rows, err := db.Query(sqlQuery, id)
+	if err != nil {
+		return nil, convertPostgresError(err)
+	}
+
+	defer rows.Close()
+
+	notes, err := returnNotes(rows)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(notes) > 1 {
+
+		return nil, QueryResultContainedMultipleRowsError
+	}
+
+	if len(notes) < 1 {
+		return nil, QueryResultContainedNoRowsError
+	}
+
+	return notes[0], nil
+}
+
+func DeleteNote(id int64) error {
+	sqlQuery := `
+		DELETE FROM note
+		WHERE id = $1`
+
+	rows, err := db.Query(sqlQuery, id)
+	if err != nil {
+		return convertPostgresError(err)
+	}
+	defer rows.Close()
+
+	if err := rows.Err(); err != nil {
+		return convertPostgresError(err)
+	}
+
+	return nil
+}
+
 func StoreNewNote(authorId int64, content string, creationTime time.Time) (int64, error) {
 	sqlQuery := `
 		INSERT INTO note (author_id, content, creation_time)

handlers/handlers.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"html/template"
 	"net/http"
+	"strconv"
 	"strings"
 	"time"
 
@@ -292,8 +293,34 @@ func HandleNoteApiRequest(
 
 		responseWriter.WriteHeader(http.StatusCreated)
 
+	case http.MethodDelete:
+
+		id, err := strconv.ParseInt(request.URL.Query().Get("id"), 10, 64)
+		if err != nil {
+			http.Error(responseWriter, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		note, err := noteservice.GetNoteById(id)
+		if err != nil {
+			http.Error(responseWriter, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		if note.AuthorId != userId {
+			errorString := "You are not the author of this note. you are only allowed to delete your own notes"
+			http.Error(responseWriter, errorString, http.StatusUnauthorized)
+			return
+		}
+
+		err = noteservice.DeleteNoteById(note.Id)
+		if err != nil {
+			http.Error(responseWriter, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
 	default:
-		respondWithMethodNotAllowed(responseWriter, http.MethodGet, http.MethodPost)
+		respondWithMethodNotAllowed(responseWriter, http.MethodGet, http.MethodPost, http.MethodDelete)
 	}
 }
 

migrations/0000_createDbs.sql

@@ -19,17 +19,17 @@ CREATE TABLE IF NOT EXISTS publication (
 
 CREATE TABLE IF NOT EXISTS note (
 	id bigserial PRIMARY KEY,
-	author_id bigint references app_user(id) NOT NULL,
+	author_id bigint references app_user(id) ON DELETE CASCADE NOT NULL,
 	content text NOT NULL,
 	creation_time timestamp NOT NULL
 );
 
 CREATE TABLE IF NOT EXISTS note_to_publication_relationship (
-	note_id bigint PRIMARY KEY references note(id),
-	publication_id bigint references publication(id) NOT NULL
+	note_id bigint PRIMARY KEY references note(id) ON DELETE CASCADE,
+	publication_id bigint references publication(id) ON DELETE CASCADE NOT NULL
 );
 
 CREATE TABLE IF NOT EXISTS note_to_category_relationship (
-	note_id bigint PRIMARY KEY references note(id),
+	note_id bigint PRIMARY KEY references note(id) ON DELETE CASCADE,
 	type category NOT NULL
 );

migrations/tools/drop_everything.sql

@@ -6,6 +6,6 @@ DROP TABLE publication CASCADE;
 
 DROP TABLE note CASCADE;
 
-DROP TABLE note_to_type_relationship CASCADE;
+DROP TABLE note_to_category_relationship CASCADE;
 
 DROP TABLE note_to_publication_relationship CASCADE;

services/noteservice/noteservice.go

@@ -30,6 +30,26 @@ func StoreNewNote(
 	return nil
 }
 
+func GetNoteById(id int64) (*models.Note, error) {
+	noteData, err := databaseutil.GetNote(id)
+
+	if err != nil {
+		return nil, err
+	}
+
+	return &models.Note{
+			Id:           noteData.Id,
+			AuthorId:     models.UserId(noteData.AuthorId),
+			Content:      noteData.Content,
+			CreationTime: noteData.CreationTime,
+		},
+		nil
+}
+
+func DeleteNoteById(id int64) error {
+	return databaseutil.DeleteNote(id)
+}
+
 func StoreNoteCategoryRelationship(
 	note *models.Note,
 	category models.Category,

static/js/base.js

@@ -0,0 +1,32 @@
+$(function() {
+  // http://stepansuvorov.com/blog/2014/04/jquery-put-and-delete/
+  jQuery.each( [ "put", "delete" ], function( i, method ) {
+    jQuery[ method ] = function( url, data, callback, type ) {
+      if ( jQuery.isFunction( data ) ) {
+        type = type || callback;
+        callback = data;
+        data = undefined;
+      }
+
+      return jQuery.ajax({
+        url: url,
+        type: method,
+        dataType: type,
+        data: data,
+        success: callback
+      });
+    };
+  });
+
+  jQuery.prototype.getDOM = function() {
+    if (this.length === 1) {
+        return this[0];
+    }
+
+    if (this.length === 0) {
+      throw "jQuery object is empty"
+    }
+    throw "jQuery Object contains more than 1 object";
+  };
+
+});

templates/base.tmpl

@@ -20,6 +20,7 @@
             <script src="//cdn.muicss.com/mui-0.9.36/js/mui.min.js"></script>
             <script src="//ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
             <script src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.22.2/moment.min.js"></script>
+            <script src="/static/js/base.js"></script>
             {{ block "js" . }} {{ end }}
         </head>
         <body>