How do I concatenate 2 strings in Django - html

I need to show an image of the database, but I need to insert a slash before {{...}} because only then does the file access the static folder. What should I do?

You can do this like recommended in the two comments but actually django coveres this exact usecase. What you are searching is an administration of your static files, the docs are here: https://docs.djangoproject.com/en/1.11/howto/static-files/ .
If you want to have your files organised with the orm, checkout https://docs.djangoproject.com/en/1.11/topics/files/ especially the second code snippet. A File object gives you a name, path and url which should cover all your needs including absolute and relativ paths for your files.

Related

Distribution file source is different to development path source

I've started using a task runner to export all of my folders into a distribution folder using Gulp. The problem arises when I export images into the distribution folder, the path name is different from the one I'm using in my src file. So, as an example, when I target an image in HTML I type:
/assets/images/example.jpg
However, when the HTML file is distributed, it is supposed to target:
/images/example.jpg
It's still pointing to the assets folder, and creates a dead link. Should I be using a module like gulp-replace to automatically change these path names? Or should I just type in the assumed path name? Or, is there another method that I'm missing?
Sorry if I've phrased this badly, I'm working towards a new developer environment - let me know if I can provide you with any other details.
Should I be using a module like gulp-replace to automatically change
these path names?
Yes, gulp-replace will do the trick.
As an alternative you can place your index.html file into assets folder, so you don't need to change any paths when distributing the project.

Is it possible to retrieve text files content from a parameter and display in HTML?

Say I have a product listing with descriptions. Can I store the descriptions in text files and call them by setting a parameter path in web.xml? Is that even possible? Calling txt file extensions?
It may be a stupid question but I have no clue... Would it slow down the app if I host everything in separate files instead of the database?
Yes, very much so; you are referring to static sites, which may be pre-generated or may be very simple wrapped by jsp. Take a look at static site generators.

Swagger API Specification filenames

I'm trying to use Swagger to create API documentation for an API we're building and I've never used it before.
The documentation on Github says that the Resources Listing needs t be at /api-docs and the various resource files need to be at /api-docs/books etc.
This makes naming files and folders very tricky. I think they expect the files to have no file names, rather than having a folder called /api-docs it has to be an extension-less file, then you can't put the resources in an api-docs folder because you can't call the folder that, so they suggest using a folder called /listings.
This folder doesn't appear in the URL structure of your documentation though, it's kind of invisible because you set the baseURL in your resources to the proper path, but it looks like that has to be an absolute path, which is awkward if you want to have it on several servers (local and production).
Maybe I just don't get it but this all seems to be absolutely nuts.
So, I have 2 questions.....
1) Can I give my resource listing file and my resource files a .json extension? This would make sense as it's a JSON file.
2) Can I use a relative path to the resource listing file in the baseURL in my resource files?
Ideally, my file structure would be flatter, like this...
/api-docs
resources.json
books.json
films.json
Is Swagger flexible enough to do this?
It's an IIS server if that makes any difference (if the solution requires routing for example).
I was able to put model files into a folder under the web root and could reference them like this.
$ref: '/models/model.yml#/MyObject'
Relative paths also worked without a leading slash.
$ref: 'models/model.yml#/MyObject'
Inside the model.yml, I can reference other objects int eh same file like this
$ref: '#/MyObject2'.
However, I could only get the main swagger file to import model files. I could not get one model file to cross-reference another model file.
I was using a Tomcat web server but the principle will be the same.

How to handle uploading html content to an AppEngine application?

I would like to allow my users to upload HTML content to my AppEngine web app. However if I am using the Blobstore to upload all the files (HTML files, css files, images etc.) this causes a problem as all the links to other files (pages, resources) will not work.
I see two possibilities, but both of them are not very pretty and I would like to avoid using them:
Go over all the links in the html files and change them to the relevant blob key.
Save a mapping between a file and a blob key, catch all the redirections and serve the blobs (could cause problems with same name files).
How can I solve this elegantly without having to go over and change my user's files?
Because app engine is running your content on multiple servers, you are not able to write to the filesystem. What you could do is ask them to upload a zip file containing their html, css, js, images,... The zipfile module from python is available in appengine, so you can unzip these files, and store them individually. This way, you know the directory structure of the zip. This allows you to create a mapping of relative paths to the content in the blobstore. I don't have enough experience with zipfile to write a full example here, I hope someone more experienced can edit my answer, or create a new one with an example.
Saving a mapping is the best option here. You'll need to identify a group of files in some way, since multiple users may upload a file with the same name, then associate unique pathnames with each file in that group. You can use key names to make it a simple datastore get to find the blob associated with a given path. No redirects are required - just use the standard Blobstore serving approach of setting the blobstore header to have App Engine serve the blob to the user.
Another option is to upload a zip, as Frederik suggests. There's no need to unpack and store the files individually, though - you can serve them directly out of the zip in blobstore, as this demo app does.

Output reformatted text within a file included in a JSP

I have a few HTML files that I'd like to include via tags in my webapp.
Within some of the files, I have pseudo-dynamic code - specially formatted bits of text that, at runtime, I'd like to be resolved to their respective bits of data in a MySQL table.
For instance, the HTML file might include a line that says:
Welcome, [username].
I want this resolved to (via a logged-in user's data):
Welcome, user#domain.com.
This would be simple to do in a JSP file, but requirements dictate that the files will be created by people who know basic HTML, but not JSP. Simple text-tags like this should be easy enough for me to explain to them, however.
I have the code set up to do resolutions like that for strings, but can anyone think of a way to do it across files? I don't actually need to modify the file on disk - just load the content, modify it, and output it w/in the containing JSP file.
I've been playing around with trying to load the files into strings via the apache readFileToString, but I can't figure out how to load files from a specific folder within the webapp's content directory without hardcoding it in and having to worry about it breaking if I deploy to a different system in the future.
but I can't figure out how to load files from a specific folder within the webapp's content directory without hardcoding it in and having to worry about it breaking if I deploy to a different system in the future.
If those files are located in the webcontent, use ServletContext#getRealPath() to convert a relative web path to an absolute disk file system path. This works if the WAR is exploded in the appserver (most does it by default, only Weblogic doesn't do that by default, but this is configureable IIRC). Inside servlets you can obtain the ServletContext by the inherited getServletContext() method.
String relativeWebappURL = "/html/file.html";
String absoluteFilePath = getServletContext().getRealPath(relativeWebappURL);
File file = new File(absoluteFilePath);
// ...
Alternatively, you can put it in the classpath of the webapplication and make use of ClassLoader#getResource():
String relativeClasspathURL = "/html/file.html";
URL absoluteClasspathURL = Thread.currentThread().getContextClassLoader().getResource(relativeClasspathURL);
File file = new File(absoluteClasspathURL.toURI());
// ...
As to the complete picture, I question if you have ever considered an existing templating framework like Freemarker or Velocity to ease all the job?