{"id":12944,"date":"2014-04-12T23:30:23","date_gmt":"2014-04-12T18:00:23","guid":{"rendered":"http:\/\/www.tothenew.com\/blog\/?p=12944"},"modified":"2016-12-19T15:31:08","modified_gmt":"2016-12-19T10:01:08","slug":"_id-with-mongoose","status":"publish","type":"post","link":"https:\/\/www.tothenew.com\/blog\/_id-with-mongoose\/","title":{"rendered":"_id With Mongoose"},"content":{"rendered":"

Let us take a very common use-case: “There will be a registration page for users, where users will provide their required details along with their picture<\/strong>\u201d.<\/p>\n

Details would be saved to MongoDB<\/strong> while the pictures would be uploaded to Cloudinary or S3<\/strong> with user unique id<\/strong>.”
\nSuppose we have User<\/strong> Schema<\/strong> as given below:
\n[js]
\n\/*
\n * Schema Defined with Mongoose.
\n * *\/
\nvar UserSchema = mongoose.Schema({
\n name: {type: String, required: true},
\n age: {type: Number, min: 16, max: 60, required: true},
\n password: {type: String, required: true},
\n});
\nvar User = mongoose.model(‘User’, UserSchema);
\n[\/js]
\nWe have custom fileManager module to upload image on Cloudinary\/S3, we requiring as below:
\n[js]
\n\/*
\n * file Manager custome Module to upload image to Cloudinary\/S3
\n * *\/
\nvar fileManager = require("Cloudinary\/S3 File Manager");
\n[\/js]
\nNow suppose user provided the following details at the time registration:
\n[js]
\n\/*
\n * Details provided by user
\n * *\/
\nvar userDetails = {
\n name: "Amit Thakkar",
\n age: 25,
\n password: "igblog",
\n image: "imagePath"
\n};
\n[\/js]
\nTo achieve this use-case, let us discuss the approach we were following earlier. As we are familiar with _id<\/strong> field, which MongoDB<\/strong> auto generates for every document in case it is not provided at the time of saving\/inserting, and is unique<\/strong> for the whole collection<\/strong>. So first we saved user details to MongoDB<\/strong>, then we got unique<\/strong> _id<\/strong> field (which is auto generated<\/strong> by MongoDB<\/strong>) for that user, and then only we uploaded user image to Cloudinary\/S3 with that _id<\/strong>. If at the time of uploading the image to Cloudinary\/S3, any error occurred (because of any reason), then we removed the saved user details from MongoDB<\/strong> and then sent error message in response. Let\u2019s see this with the help of code:
\n[js]
\n\/*
\n * What we were doing earlier
\n * *\/
\nnew User(userDetails).save(function (error, user) {
\n if (error) {
\n \/\/ Return Error Message
\n } else {
\n \/\/ Uploading Image to Cloudinary\/S3
\n var options = {
\n publicId: user._id,
\n path: userDetails.image
\n };
\n fileManager.uploadImage(options, function (error, result) {
\n if (error) {
\n User.remove({_id: user._id}, function (error, removed) {
\n if(error) {
\n \/\/ log ERROR
\n }
\n });
\n \/\/ Return ERROR Message
\n } else {
\n \/\/ Return SUCCESS Message
\n }
\n });
\n }
\n});
\n[\/js]
\nEarlier if any error occurred at the time of uploading image to Cloudinary\/S3, we used to hit two queries to MongoDB<\/strong> (first one for inserting\/saving the user details and second one for removing the userdetails). In order to avoid these two MongoDB<\/strong> queries, we are now using _id<\/strong> field generated By Mongoose<\/strong>. Mongoose<\/strong> provides us an _id<\/strong> field to read before saving the document (user details) to MongoDB<\/strong>. When we do new User(userDetails), then Mongoose<\/strong> returns user(new Model Object of User) with _id<\/strong> field. We use that _id<\/strong> field for uploading image to Cloudinary\/S3, and if image is uploaded successfully then only we save user details to MongoDB<\/strong>, otherwise return ERROR.
\n[js]
\n\/*
\n * New approach
\n * *\/
\nvar user = new User(userDetails);
\nvar options = {
\n publicId: user._id,
\n path: userDetails.image
\n};
\n\/\/ Uploading Image to Cloudinary\/S3
\nfileManager.uploadImage(options, function (error, result) {
\n if (error) {
\n \/\/ Return ERROR Message
\n } else {
\n user.save(function (error, user) {
\n if (error) {
\n \/\/ Return Error Message
\n } else {
\n \/\/ Return SUCCESS Message
\n }
\n });
\n }
\n});
\n[\/js]
\nSo with the second way, we can write more clean and optimized code.<\/p>\n

NOTE:<\/strong> When we are saving document via mongoose<\/strong>. _id<\/strong> field is auto generated by Mongoose<\/strong> and gets attached to the Model<\/strong>, and at the time of saving\/inserting the document into MongoDB<\/strong>, MongoDB<\/strong> will use that unique<\/strong> _id<\/strong> field which was generated by Mongoose<\/strong>.<\/p>\n

Amit Kumar
\namit.kumar@intelligrape.com<\/a>
\nin.linkedin.com\/in\/amitkumar0110
\ntwitter.com\/amit_kumar0110
\nMore Blogs by Me<\/a><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Let us take a very common use-case: “There will be a registration page for users, where users will provide their required details along with their picture\u201d. Details would be saved to MongoDB while the pictures would be uploaded to Cloudinary or S3 with user unique id.” Suppose we have User Schema as given below: [js] […]<\/p>\n","protected":false},"author":52,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"iawp_total_views":4},"categories":[1185],"tags":[1383,4846,1316,1177],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/12944"}],"collection":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/users\/52"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/comments?post=12944"}],"version-history":[{"count":0,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/12944\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/media?parent=12944"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/categories?post=12944"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/tags?post=12944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}