I have an app which uses a xml file as database. This file is created in the project as you see:
I want to keep this file updated by the following procedure in the splash screen:
procedure
get the last modified dates of the local xml file and the remote xml
file(http://www.somewhereontheinternet.com/data.xml)
compare these two dates
if the remote one has the most recent modified date then download
it and replace the local one with it
The application will be deployed to the clients via Windows Store.
If you think about the restrictions, limitations, policies and possibilities, can I keep the deployed app's database files updated as described above? If not how can I keep my app's data updated then?
Few things:
1) It will be more clean to do this by associating a version to the database. local version can be stored in the application data as local state or setting. remote version can be queried using a web api.
2) do you want user to know about this? can user force update of the database? accordingly, knobs may need to be exposed in the UI.
3) if the size of the file is significant, may have to do the download using background transfer.
steps will look something like this:
check remote version when the app is launched (async).
if the versions differ, schedule background transfer or download while the app is running depending on the size of the file.
Related
I building a new course-like web application. There will be plenty of images, video and sound files.
I am wondering about possible strategies for static file management between app environments.
My current approach is to use SQL database to store image urls, which will be uploaded via admin panel on the website. The images are to be stored in a blob-like storage (AWS S3 bucket).
This however, when doing changes, requires to upload the image to each environment or create a data migration dev -> staging -> prod in a deployment pipeline.
Am I missing something here? Even if I store files in a single place (single storage account) for all environments, I still need to migrate the database records when making changes to the course.
Should I just apply the changes in prod and create some basic migration data for dev/uat course testing?.
To emphasize, files will only be uploaded by an admin, not by a user. For example, admin uploads the image via admin panel and the image will be automatically included in the course.
I am not sure what's the appropriate way of doing this to manage and test changes properly. If I allow to do this on prod directly without migration, then I'm running the risk of uploading something invalid into the course with untested changes. On the other hand , I am not sure if it's common to migrate SQL data between databases and it will also have it's own pitfalls.
I am using database connector component, with vault component to store the database credentials. Now as per the documentation of both components i have created different properties file for each environment to store the encrypted credentials for diff env.
Following is the structure of my mule project
Now the problem with this structure is that i have to build new deployable zip file whenever i have to update the database credentials for any environment.
I need a solution where i can keep all credentials encrypted and centralized and i don't have to create a build every time after updated the credentials, We can afford to restart the server, but building new zip and deploying is really cumbersome.
Second problem we have this approach is a developer needs to know the production db to update it in properties file, this is also a security issue.
Please suggest alternate approach for credentials management for mule projects.
I'm going to recommend you do NOT try to change the secure solution provided to you by MuleSoft. To alleviate the need for packaging and deployment, you would have to extract the properties files outside of the deployment and this would be a huge risk. Regardless of where you store the property files within the deployment if you change the files, you have to package and re-deploy. I see the only solution to your problem as moving the files outside of the deployment and securely storing them. Mule has provided a solution while it may be cumbersome, they are securing these files first with encryption and secondly within the server container. You can move out the property files but you have to provide a custom implementation and you will be assuming great risk to your protected resources.
Set a VM arguement e.g. environment.type=local for local machine on your anypoint studio.
Read this variable in wherever you are reading your properties file in a way that environment type is read dynamically such as below.
" location="classpath:properties/sample-app-${environment.type}.properties" doc:name="Secure Property Placeholder"/>
In order to set the environment type on your production server(or wherever you are using mule runtime), open \conf\wrapper.conf and add the arguement wrapper.java.additional.=-Dserver.type=production. If you already have any property in this file, you may need to set the value of n appropriately. For example 13 or 14.
This way you don't need to generate different deployment artefacts for different environment because correct properties file is picked by using environment specific VM arguement.
For example I have a client-server application, this application often gets updated (it's an exe file). If I download the update on the server machine then the same update should be transfered to the client machines, or vice-versa.
At the moment the update is downloaded on all machines individually. My idea is downloading the update should be done only on the server and I'm planning to make an option in the client to copy the *.exe file (update) directly from the server and paste it on the installation path.
How can I make this happen?
NOTE : the update is a self extracting file.
There is already a technology for achieving this called ClickOnce. The client application can be "published" to a share that is accessible to all the clients, then each time the client is executed a version check is done - if a later version is detected on the share then it is downloaded before execution continues.
You can read more about this here: ClickOnce Security and Deployment. Creating a ClickOnce package and publishing it is a feature already built into Visual Studio, so you do not need to write any code.
You have to write an application that will be split into different parts :
Detect file change either on the client or server machine
Perform the copy of the exe file to server or other clients.
In all cases you can't tell an exe file to update it self.
Under VB.Net 2005, I created a Setup Project which produced installation files for a windows application. I placed the mdb file in the User's Application Data Folder and remapped the DataDirectory to Environment.SpecialFolder.ApplicationData at runtime. Unfortunately, sometimes the system just did create the mdb file at the Application Directory. An example was that I installed the program in Windows 7 under a normal user account. I chose inside the installer that the program would be made available to everyone. After installation, the mdb file would be created automatically for the Administrator account but not for the normal user account. For XP, the whole thing worked fine.
I am tempted to write a routine to check and create the mdb file if it is not present, but why does this happens and what other opinions do I have?
If the application is installed for all users instead of once for each user that logs onto the machine, then you will eventually run into a problem where the database isn't available for the signed on user.
In order to resolve this, you would probably be better off checking for the existence of the database on application startup and then either copying a standard version from the application directory to the current user's data directory or creating a new db from scratch in place. I would recommend the first approach.
I would like to make a complete backup of my whole joomla 1.5 based site from time to time. How would this ideally be done? Are there any common pitfalls? Not that I only have ftp access to the hosting server. Is there a step by step tutorial somewhere? I am using latest Joomgallery and Kunena 1.0.9 (Legacy mode).
Maybe there is a good way to automate this?
There's two parts of the backup you have to worry about, the database and the files.
The first part is the database. It can be backed up using something like phpMyAdmin. If you don't have this available on your server already, it's not too hard to upload and get it going yourself. From there, you can just Export the entire database to a gzip file.
The second part is the code and uploaded files. The code base shouldn't change too often, so you could probably just make one backup of this. There's a number of ways. The simplest is to just download the entire folder via FTP, though if you're Linux, I'm sure someone will know a single command line to get all the changed files (rsync?).
The database is the main thing you have to worry about though: everything else should be able to be rebuilt just by reinstalling.
I think this: http://www.joomlapack.net/ is what you need. I use it myself and it works like a charm. Both for backups and for moving my Joomla installations from developer sites and to the real site.
get an FTP synchronisation tool and keep an up-to-date copy of your site locally. Then you could run the batch script
mysqldump -hhost -uuser -p%1 schema > C:\backup.sql
to create a backup of your mysql tables at various points in time.
edit
you would have to have MySQL Server installed on your local machine and path to its bin directory in you PATH, in order to run the mysqldump command without much hassle. -p%1 would take the command-line provided password, as you wouldn't want to store passwords in your batch script.
If you only have FTP access you are in a bit of a problem, as beside all files you'll also have to backup the database. Without accessing the database, a full-backup won't do you any good.
Whatever backup strategy you choose - be sure it can handle UTF-8 correctly. Joomla 1.5 stores all content with UTF-8, even when the database charset is set on 'iso-5589-1' - so when the backup solution is detecting the database charset, some characters like € or é will result in "strange" ¬ / é - not really what you'll want.
I absolutely endorse using Joomlapack - it works great. The optional remote tools allow you to initiate the backup from a Windows desktop machine - it performs the backup and downloads it. The remote has a scheduler, and you can also set it off to backup and download a list of sites.
Joomlapack also provides a file "kickstart.php" which you copy to your empty server account along with the backup, which automates the restore procedure. You do have to create an empty database with PHPMyAdmin or similar, and you are given the opportunity to supply the database parameters (host, database, username, password) during the process.
One pitfall I did run into with this though is that some common components can have absolute URLs in their configuration - e.g. SOBI2, Virtuemart. It's then just a matter of finding the appropriate configuration file, editing it and re-uploading it.
Another problem was one archive file (either ZIP or their JPA format) got a filename with a "?" character in it (from a Linux server) and this caused a bit of a problem trying to install it locally on a Windows WAMP stack - the extract process on the ZIP file failed, and it stopped the process completing cleanly.
I suggest using automatic backup service by http://www.everlive.net
Update:
Ok, here is some more information. EverLive.net is a website where you can create a free account. Enter your website details and you are ready to take your backups withe just one click. Restore is also possible in the same way.
Further you can use automatic backup option to take automatic backups at defined intervals. Other than that, you can use the website health check service to inform you if your website is not available.