My colleagues and I are building a web app with a relatively complex back end. Without giving away the product idea, we have several hundred form schemas paired with their return functions which are called when the form is submitted. The schemas are JSON objects which dynamically create a form on the client side. When the data in the form is submitted the linked functions may do a variety of different things with that data.
Currently these form schemas and linked functions are hosted in a private repo on GitHub. Is this the best way to go or could they be persisted in a database such as mongodb?
I understand mongodb will have no trouble storing the form schemas but what about the functions and the functions dependencies?
Store it into the database (as a string) and give it to the client when he requests it (will turn into a function). If you want to use that code on the backend (node), you'd eval it or make a function new Function(functionString) and do your validating on the server side as well.
/edit
Or put each schema in a file and request it server/client side when you need it. Making a DB round for something like this is expensive.
Related
I want to sync data between two different backends, one written in Javascript and the other in Java.
The JS backend has its data stored in a MongoDB but the Java backend contains some hardcoded data that I need to fetch in order to store it the DB of the JS backend.
Now my question is what are the possible solutions to do that from an architecture perspective?
You have a "Split-Brain". You can only use one Data Store. You have to migrate the Hardcoded Date to MangoDB an to read the data from there.
In my application I receive json data in a post request that I store as raw json data in a table. I use postgresql (9.5) and node.js .
In this example, the data is an array of about 10 quiz questions experienced by a user, that looks like this:
[{"QuestionId":1, "score":1, "answerList":["1"], "startTime":"2015-12-14T11:26:54.505Z", "clickNb":1, "endTime":"2015-12-14T11:26:57.226Z"},
{"QuestionId":2, "score":1, "answerList":["3", "2"], "startTime":"2015-12-14T11:27:54.505Z", "clickNb":1, "endTime":"2015-12-14T11:27:57.226Z"}]
I need to store (temporarily or permanently) several indicators computed by aggregating data from this json at quizz level, as I need these indicators to perform other procedures in my database.
As of now I was computing the indicators using javascript functions at the time of handling the post request and inserting the values in my table alongside the raw json data. I'm wondering if it wouldn't be more performant to have the calculation performed by a stored trigger function in my postgresql db (knowing that the sql function would need to retrieve the data from inside the json raw data).
I have read other posts on this topic, but it was asked many years ago and not with node.js, so I thought people might have some new insight on the pros and cons of using sql stored procedures vs server-side javascript functions.
edit: I should probably have mentioned that most of my application's logic already mostly lies in postgresql stored procedures and views.
Generally, I would not use that approach due to the risk of getting the triggers out of sync with the code. In general, the single responsibility principle should be the guide: DB to store data and code to manipulate it. Unless you have a really pressing business need to break this pattern, I'd advise against it.
Do you have a migration that will recreate the triggers if you wipe the DB and start from scratch? Will you or a coworker not realise they are there at a later point when reading the app code and wonder what is going on? If there is a standardised way to manage the triggers where the configuration will be stored as code with the rest of your app, then maybe not a problem. If not, be wary. A small performance gain may well not be worth the potential for lost developer time and shipping bugs.
Currently working somewhere that has gone all-in on SQL functions.. We have over a thousand.. I'd strongly advise against it.
Having logic split between Javascript and SQL is a real pain when debugging issues especially if, like me, you are much more familiar with JS.
The functions are at least all tracked in source control and get updated/created in the DB as part of the deployment process but this means you have 2 places to look at when trying to follow the code.
I fully agree with the other answer, single responsibility principle, DB for storage, server/app for logic.
I have my server in nodejs and client in angularjs, mongodb(mongoose) as database. I want my client to be able to make a search query with all the normal consitions put in like fixing few fields to certain values, search string contained in few of the fields etc
query can be
(value of field A can be 'x' or 'y') and
(value of field B can range between dates P and Q) and
(string s contained in fields C or D or E) few more
is there any npm plugin or standardisation I can follow to enrich my server side API and also directly put the expression while querying with out doing a map reduce with multiple queries(with lots of code).
Yes, there are a few. I only know of those that work with Mongoose so if you're using another driver you may need to modify them a bit.
With each of these you'll need to determine which to filter locally and which to let the server handle it. Where you filter should depend largely on how much data you have. Personally, it made more sense to abandon local filtering for my largest sets and simply rely on MongoDB to handle the workload.
angoose
Connecting Mongoose and Angular and More
The original motive for Angoose project is to do away with the dual
model declarations(server and client side) if we are building a rich
model based SPA application using modern Javascript framework such as
Angular and node.js. With both front end and backend using Javascript,
Angoose allows the server side models and services to be used in the
client side as if they reside in the client side.
Angoose depends on following frameworks and assumes you have basic
familarities with them:
mongoose
express
angular (optional, for non-angular app, jQuery is required)
Mongoose Api Query
Mongoose plugin that takes a set of URL params and constructs a query for use in a search API. Also, worst project name ever.
If you use Mongoose to help serve results for API calls, you might be
used to handling calls like:
/monsters?color=purple&eats_humans=true
mongoose-api-query handles
some of that busywork for you. Pass in a vanilla object (e.g.
req.query) and query conditions will be cast to their appropriate
types according to your Mongoose schema. For example, if you have a
boolean defined in your schema, we'll convert the eats_humans=true to
a boolean for searching.
It also adds a ton of additional search operators, like less than,
greater than, not equal, near (for geosearch), in, and all. You can
find a full list below.
When searching strings, by default it does a partial, case-insensitive
match. (Which is not the default in MongoDB.)
Angular Bridge
Link models easily via a REST interface between Mongoose/Node-Express/Angular.js
Create, read, update, delete MongoDB collections via AngularJS.
It uses :
Mongoose for accessing to Mongodb
Express for the routing
AngularJS (with the $resource method)
I have a JavaScript application which uses a PouchDB instance to store data. I'd like to replicate that data to a Cloudant instance.
Most of the clients using my app and generating the data are anonymous. I'd like to still collect their data without requiring them to log in or sign up. All of the data they generate is stored in a single document. As you can probably tell, this presents a security challenge.
On the one hand, I'd like to permit anyone to read and write to my CouchDB instance, but I only want to give them access to their data. So, if an anonymous user creates a document, I'd like to only allow them to read/write to that document and not others. I don't want them to simply be able to download my entire database.
Reading the Cloudant and CouchDB documentation, it doesn't seem entirely clear how to achieve this. It looks like the following are possibilities:
Create a new database user each time an anonymous user starts generating data and only give that user access to the document they're going to create.
Create a new database for each anonymous user and somehow replicate that into the centralized database.
Figure out how to securely and transparently authenticate anonymous users.
I'm at a loss, probably due to my inexperience with Couch. How would you implement this?
I'm sure the explanation above will need clarification, so please ask away. Thanks in advance for everyone's help.
Short Version:
In a java web app, I can set javabean objects as requestscoped parameters, and access detailed fields, even hierarchical, within these objects through i.e. JSTL/EL while building a website.
Can I in any way access the full extent of these JavaBeans, in i.e. javascript-functions that are fired on, for instance, onclick of some elements within my web page?
Long version:
I am making a java web-app, and I am trying to learn the basics, so I am not using any frameworks like Spring or Struts, but I am building the app by the front controller pattern.
I have a page, which should be able to create new, recieve, edit and/or finally update data in my database. The database has foreign keys, and my choices in the editor should depend on the number of elements of other linked tables in the database.
I would like my editor to be able to:
Create the editor menu based on secondary tables of the database (static until leaving the site)
Load data from a database-element
Edit data in html-elements
Undo changes (which is basically repeating step 2, if data is available still)
Save data, and reset editor.
Point 4 is the center of attention here. I wish to be able to do step 4 without reloading the whole page. If I am able to do this, I figure step 2 should also be executed client side, as it does the same thing, only first time. It feels like a setup like this will grant me a good seperation of creating the form itself server side, and let step 2-4 happen client side, until step 5 again requires server side action.
I am not sure how to approach this goal though, or if it is a good idea. It is only a problem, when data is loaded from the database, and I want to store that data client side. Right now I am building the form in jsp/html/jstl, and I am using requestScoped java objects to do it, through a HttpServletRequest-object from the Servlet Controller. I have been trying to use these objects in javascript functions, with limited success. I have been able to extract all data, even hierirchal object's fields, except those in collections. Unfortunately these are essential to my editor page.
I have been looking into JSON for this, but is seems like i need to do big adjustements in my java code to implement this. Is it worth it?
finally, to repeat the question: How can I access requestScoped JavaBean-objectdata to be available client side, in i.e. Javascript?