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@ -1311,15 +1311,15 @@ course so it might be written and integrated in future.
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### Fileserver
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The fileserver provides access to a shared storage space that contains files
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submitted by students, supplementary files such as test inputs and outputs and
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results of evaluation. In other words, it acts as an intermediate storage node
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for data passed between the frontend and the backend. This functionality can be
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easily separated from the rest of the backend features, which led to designing
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the fileserver as a standalone component. Such design helps encapsulate the
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details of how the files are stored (e.g. on a file system, in a database or
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using a cloud storage service), while also making it possible to share the
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storage between multiple ReCodEx frontends.
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The fileserver provides access over HTTP to a shared storage space that contains
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files submitted by students, supplementary files such as test inputs and outputs
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and results of evaluation. In other words, it acts as an intermediate storage
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node for data passed between the frontend and the backend. This functionality
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can be easily separated from the rest of the backend features, which led to
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designing the fileserver as a standalone component. Such design helps
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encapsulate the details of how the files are stored (e.g. on a file system, in a
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database or using a cloud storage service), while also making it possible to
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share the storage between multiple ReCodEx frontends.
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For early releases of the system, we chose to store all files on the file system
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-- it is the least complicated solution (in terms of implementation complexity)
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@ -1337,11 +1337,15 @@ A simple solution to this problem is storing supplementary files under the
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hashes of their content. This ensures that every file is stored only once. On
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the other hand, it makes it more difficult to understand what the content of a
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file is at a glance, which might prove problematic for the administrator.
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A notable part of the fileserver's work is done by a web server (e.g. listening
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to HTTP requests and caching recently accessed files in memory for faster
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access). What remains to be implemented is handling requests that upload files
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-- student submissions should be stored in archives to facilitate simple
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However, human-readable identification is not as important as removing
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duplicates -- administrators rarely need to inspect stored files (and when they
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do, they should know their hashes), but duplicate files occupied a large part of
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the disk space used by CodEx.
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A notable part of the work of the fileserver is done by a web server (e.g.
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listening to HTTP requests and caching recently accessed files in memory for
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faster access). What remains to be implemented is handling requests that upload
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files -- student submissions should be stored in archives to facilitate simple
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downloading and supplementary exercise files need to be stored under their
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hashes.
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