I'm having a problem with my re-frame application. I can't figure out how to connect it to a local database on my machine.
In other applications I've written, I've had to add the database specifications (username, password etc) into profiles.clj. Should I create profiles.clj and add the location of my database there? And does this mean I have to update the project.clj as well?
Finally, do the queries to the database, such as GET and POST requests, go in db.cljs.
I apologise if these questions are trivial but after reading the documentation several times I am still a little confused
re-frame is a framework for building client-side web applications. You won't be able to do generic database queries as most databases don't support direct access from a browser.
I'm having a problem with my re-frame application. I can't figure out how to connect it to a local database on my machine.
You probably need to create a middle API tier that accepts REST requests from re-frame, and queries the database, returning JSON back to the client.
Finally, do the queries to the database, such as GET and POST requests, go in db.cljs
Those are probably queries to your API tier? They can live anywhere that you would like.
One thing to clarify: re-frame has an app-db that it uses and refers to. This is a client-side database of local state that lives in your application. It doesn't have a connection to the backend, at least not without you writing more code for it. It sounds like you might be confusing these?
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Can someone explain to me why you can't connect to a MySQL DB directly through dart from a security point of view?
There is no hard guideline on whether to connect frontend directly to backend or not. It is just a design practice that has been widely accepted and evolved over many years.
Typical app structure consists of
FRONTEND -> SOME MIDDLE LAYER -> BACKEND
Where your middle layer handles all the interactions/processing with the database and the frontend uses this functionality with some sort of API structure. Having this layer is extremely helpful when the application goes to scale, it gives an added abstraction to the frontend.
It is not advisable to directly fuse your frontend(your flutter app), to the DB(MySQL) because any efficient hacker might use basic man-in-middle attack to know your DB structure/connections/queries(There are some pretty effective decompilers present out there), and alter your data and you might not even get to know what caused the data to update unless you've applied some checks on DB layer.
Also, your frontend logic needs to be more of end-user centric than to handle the data of the user. Any backend system(java, node, etc) gives you added functionality & freedom to parse and present the data from either side.
You can use the sqlite package available to store basic data, like your session tokens, your app configurations etc, but it is advisable to keep the main user data like the logins, etc in a separate place, or better yet, you can use the firebase plugin to store data in document structure in the cloud.
I'm working on a project that can take data from a Weintek HMI, put them on a webserver and then send them to an application that I created on android studio.
I've found firebase that can help me in this task.
In easybuilder that works with my hmi, I can create a mysql database that can store the data.
The problem is how can I update automatically firebase database with mysql database with an interval of time in order to access them on the android app.
If there is no solution with mysql, can someone suggest other method to extract the data and use some web server to sync it with the android app?
I don't know your specific need, in terms of data volume or application, but as a workaround, maybe this can help you:
I usually apply MQTT, which many Weintek HMIs have, to send telemetry data, and then use NodeRed to process and redirect the data to a database, email, SMS, Telegram, CSV, TXT... depending on the need , which in your case could be Firebase (I never used it).
It works great for me as I don't have to worry about HMI limitations.
The problem is the reliability of the data, in terms of confirming that when the HMI sends, the server listens and writes, but there are certainly ways to deal with this, and the fact that you need to have a server with NodeRed running.
If you have never done so, in Weintek HMIs you can send the MQTT payload cyclically using macros easily.
For my Windows phone project (it's a Universal app), I have a set up that has a country and a phone number in one of the page. There are about 7 other pages that requests the user for additional information. But for starters, let's just stick with the first one, that asks for the country and the phone number.
I read through a million posts in Stackoverflow and other websites alike, to know what database system is best to implement with the sort of app I am going to be developing, or hoping to develop.
Here're my findings:
Azure SQL: I have an Azure account and I can use the Azure SQL service to store the user-input data directly to the database (when the app goes live), or while in the testing phase. But I got to know that feature isn't really working well as windows phone cannot readily update the data to Azure SQL, on realtime basis. Is it so?
MySQL: I thought I'd create a local MySQL database, for testing purposes, so as I input the data (in the emulator perhaps), the database saves it. I am unsure how I can implement this. I can't find any article I can read that can help me with this. There are with ASP.net, but it isn't what I am going to be using.
SQLite: I know for a fact the data can be stored locally, by using SQLite, but I could like to know if the locally stored data can be later updated on a server-side machine (i'd prefer Azure SQL, but MySQL is also OK with me). If it can be, i wouldn't mind settling with it. If it can't, what can I do?
It all boils down to this: What's the easiest way to store data entered in a textbox (lol, yeah!) to a database (locally or server-side)?
Your efforts to help me will be greatly appreciated!
Thanks!
You can stay on Azure SQL if you have an account.
It works fine and it updates database on the go (sends json as far as I remember), so you shouldn't worry about data being stored in a cloud. Moreover, it is super-easy to use it for your needs (store data from textbox).
Azure SQL will get your bootstrap the fastest for your application. There is no need to deploy MySQL or SQLite and managing your DB. There should not be any concern about updating the DB live from the app.
I'm working on a bunch of cakephp apps that are all services that you have access to when you login to the main website. Each app will be hosted on a separate server, and there will be a separate login server as well.
Doing the research, I found Cakephp supports writing sessions to a database, http://blog.jambura.com/2011/08/24/should-i-use-database-for-storing-sessions-in-cakephp/
And also it supports having multiple database connections,
http://bakery.cakephp.org/articles/mithesh/2008/09/02/talking-to-multiple-databases-from-single-cakephp-application
So I was considering the possibility of storing the sessions on the login server, which the other websites all access, and then they all use their own databases for the rest of their data. It seems like it would be simple to implement, but I have concern that there would be too much reading and writing on the login server's database. Is there a way to optimize for this? Or should I do another approach entirely?
Try check useDbConfig property of model. Think, that it will be simpler if your sessions and users tables will be on the same database, then you will common user database and sessions. So, you will not require to implement SSO.
I would like to make some AIR application which would be used for tracking jobs inside a company.
The idea is to create some database which will handle all the data and, when other users form other computers modify data, it is always saved on that same 'server'.
So, more than one user can edit same database, and it would be great if all the data is constantly 'refreshed' (if one user edits and saves data, on other users' computer data is instantly updated). Application would be used only in local network.
I have some data in Excel, so I also wonder if AIR can handle it somehow? Or is it better to re-structure the whole db?
So, which kind of db should I use? I've read that AIR likes SQLite very much, which would be good because I work with MySQL...
Is AIR (in combination with SQLite) able to handle ALL my needs (working over network, sharing same db, refreshing data, creating server/client applications or something, etc.)?
Thank you very much for any thoughts!
m.
There's no restrictions on what database you can use. My advice would be to create an interface in PHP or ASP or whatever language you prefer (since the Database is on a server elsewhere, you'll need some sort of network connectivity anyway), and send all requests and modifications through that.