I am working on a ruby on rails project with a requirement of creating a Deal model with an image associated with it, it has other attributes as well but I want to focus on the image aspect. I was thinking about implementing the model by having an attribute called image_file_name. This string will contain the name of the image file. I will store the image file in the folder /app/assets/images. Is this the right way to go about things? I feel that this is the wrong place to place data related files within the application. Where would I keep such image or other media data within the project folder(If I am not using a 3rd party service like AWS).
Related
I am developing an ASP.NET Core application & I need a control as described below:
Is there an existing control or a way to allow users to insert images in a textbox.
There is no way to simply insert an image into a textbox. WYSIWYG editors like TinyMCE give the appearance that this happening by rendering a HTML area with an img tag pointing to an image file at some location. In the end, what's submitted is this backing HTML, not the image itself.
For something like an image that already exists at some publicly-accessible location online, nothing more is required. However, if you're talking about allowing a user to embed an image that exists only on their local filesystem, that requires additional machinery. Again, WYSIWYG editors like TinyMCE often include something along the lines of a "file browser" or "upload" control that handles this type of thing. When the user picks an image from their computer, the control uploads that image to some location on the server and then, again, adds a simple img tag pointing to the now online location of that image. This has to be configured, though. There's usually server-side scripts that must be installed on the server and you have to somehow tell it both where to store the uploaded images and how to address them from a publicly-accessible URL. This is likely what you're missing with TinyMCE. However, setting all that up is beyond the scope of Stack Overflow. Consult the documentation for your library of choice.
I was asked to develop a game called "Flag Quiz" in which the player have to guess the correct name of the flag that appears in the middle of the screen.
Of course I have a lot of pictures (221 flags) and I have to put them inside the program because, when the button Play is pressed, the program has to pick randomly 10 of these flags.
Problem
I was thinking to use an ImageList but the flags are 480x311 and so Delphi asks me to separate the picutre in 30 different bitmaps. Can I do anything about this?
My idea, to avoid that problem, was the following (although I think that it's not very good): create 221 TPicture components (invisible to the user of course) and load in each of them a picture of a flag.
I'd prefer not using the last idea I had. Do you know any improvement?
This sort of problem is simply not suited to the form designer. You want to store 221 images, and managing that in the IDE will be horrible. Once you've got them all in you won't be able to see them readily because they will be base 16 encoded in a .dfm file. Under revision control it will be a mess because you won't be able to change individual images in a manageable and traceable manner.
The accepted way to do this is to use resources. If it were me, I'd arrange for my images to have predicatable names. For instance, flag1, flag2, etc. I'd generate a resource script (.rc) that listed all the flags. I'd compile that resource script to a compiled resource (.res) which is linked to the executable. I'd have the resource script and the image files committed to revision control.
Then at runtime you have a single TImage control to display the flag. Every time you need a new image you load it with TResourceStream, and push it into the TImage control.
Devexpress has a Componnect named cximagecolletion that you can put your images on it and save and load images from/to file
or you can save all flags in small access db and load it when you need using tadodataset
there is no doubt that if you put your images direct on your form your dfm grow very high and so you Get Into trouble
Personally I would store each file as an image in a dedicated subdirectory, using the country as a file name. Then I would read the subdirectory file names on entry to the program (so I have a list of countries that I can randomly choose from) and use TImage.LoadFromFile to display the flag. This is far easier to extend than using a resource file (IMHO).
I have a form having multiple upload fields. Let's assume a thumbnail image and the large image. Now using the FuelPHP how can i save this two files to two different locations renaming them to name desired.
For example:
I want to save the thumbnail to media/images/thumbnail/db_record_id/thumbnail.extension and the large image to media/images/large/db_record_id/thumbnail.extension
using the answer to this question Multiple uploads to different directories using FuelPHP, I can upload to the desired directories but how to give the desired name?
If you want full control, register a 'before' callback.
If will be called before saving the file, with the File object of that file. It's passed by reference, so you can alter whatever you want.
I am working on a Vegetable gardening application. Apart from the vegetable name and description I also have vegetable image. Currently, I have all the images in the Supported Files folder in the Xcode project.
But later on I want to update the application dynamically without having the user download a new version. When the user updates the application or downloads new data from the server that data will include the images. Can I store those images in the supporting file folder or somewhere where they can be references by just the name.
RELATED QUESTION:
I will also allow the user to take pictures of their vegetables and then write notes about the vegetables like "just planted", "about to harvest" etc. What is the recommended approach for storing pictures/photos. I can always store them in the user's photo library and then store the reference in the local database and then fetch and display the picture using the reference. The problem with that approach might be that if the user accidentally deletes the picture from the library then it will no longer be displayed in my application.
The only way I see if to store the picture in the app local database as a BLOB.
No you can't put the downloaded images with the others inside the supporting file folder. Also I would suggest you put the images inside an Images or Resources folder instead... If you want to download any data after the app is compiled, then they will not be in the bundle. It is the bundle you are referring to when talking about the Supported Files folder in Xcode. This is read only for your application.
Just to be clear, once compiled, there are no folder structures for your application, these "folders" are just groups in the Xcode project to keep things tidy.
If you download say a zip file containing a set of images, it's up to you to write them to disk after you download them. You should put these images in either the tmp, the cache or the documents directory.
But then you'll have to build your path before loading the images. You won't be able to just provide the name of the file such as:
[UIImage imageNamed:#"something.jpg"];
Because this will look in your bundle. Instead you must do something like this to load your image from the Documents directory for example.
Your challenge is that you will end up in a state where you'll have some images in the Bundle (the ones from when you uploaded your app), and the newer ones in the documents directory. You must them check the bundle first and if there is no image there, check the documents directory.
For user generated data, I suggest also saving the images in the Documents directory, and maintaining an SQLite database of the users data, so you can map an image name to an entry in the database. You don't want to save the images as BLOB because this will inevitably slow down the performance of your queries and add extra unnecessary load on the CPU to convert to UIImage and back.
You don't want to save their images to the gallery for 2 reasons, first this means you'll be saving in 2 places because keeping a reference in your database to an external image is very fragile and you're just asking for trouble, and secondly, once the image isn't under your wing, you don't control it anymore, the user will delete it at some point, if they go back to your app they expect to see it there.
I have a website that shows galleries. Users can upload their own content from the web (by entering a URL) or by uploading a picture from their computer.
I am storing the URL in the database which works fine for the first use case but I need to figure out where to store the actual images if a user does a upload from their computer.
Is there any recommendation here or best practice on where I should store these?
Should I save them in the appdata or content folders? Should they not be stored with the website at all because it's user content?
You should NOT store the user uploads anywhere they can be directly accessed by a known URL within your site structure. This is a security risk as users could upload .htm file and .js files. Even a file with the correct extension can contain malicious code that can be executed in the context of your site by an authenticated user allowing server-side or client-side attacks.
See for example http://www.acunetix.com/websitesecurity/upload-forms-threat.htm and What security issues appear when users can upload their own files? which mention some of the issues you need to be aware of before you allow users to upload files and then present them for download within your site.
Don't put the files within your normal web site directory structure
Don't use the original file name the user gave you. You can add a content disposition header with the original file name so they can download it again as the same file name but the path and file name on the server shouldn't be something the user can influence.
Don't trust image files - resize them and offer only the resized version for subsequent download
Don't trust mime types or file extensions, open the file and manipulate it to make sure it's what it claims to be.
Limit the upload size and time.
Depending on the resources you have to implement something like this, it is extremely beneficial to store all this stuff in Amazon S3.
Once you get the upload you simply push it over to Amazon and pop the URL in your database as you're doing with the other images. As mentioned above it would probably be wise to open up the image and resize it before sending it over. This both checks it is actually an image and makes sure you don't accidentally present a full camera resolution image to an end user.
Doing this now will make it much, much easier if you ever have to migrate/failover your site and don't want to sync gigabytes of image assets.
One way is to store the image in a database table with a varbinary field.
Another way would be to store the image in the App_Data folder, and create a subfolder for each user (~/App_Data/[userid]/myImage.png).
For both approaches you'd need to create a separate action method that makes it possible to access the images.
While uploading images you need to verify the content of the file before uploading it. The file extension method is not trustable.
Use magic number method to verify the file content which will be an easy way.
See the stackoverflow post and see the list of magic numbers
One way of saving the file is converting it to binary format and save in our database and next method is using App_Data folder.
The storage option is based on your requirement. See this post also
Set upload limit by setting maxRequestLength property to Web.Config like this, where the size of file is specified in KB
<httpRuntime maxRequestLength="51200" executionTimeout="3600" />
You can save your trusted data just in parallel of htdocs/www folder so that any user can not access that folder. Also you can add .htaccess authentication on your trusted data (for .htaccess you should kept your .htpasswd file in parallel of htdocs/www folder) if you are using apache.