Large Files

So, what are "large files" anyway?

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You're probably already familiar with small structured data; the stuff that's usually stored in a relational database like Postgres or MySQL. I'm talking about simple, primitive data types like:

user_id (integer)
is_active (boolean)
email (string)

Large files, or "large assets", on the other hand, are giant blobs of data encoded in a specific file format and measured in kilo, mega, or gigabytes. As a simple rule:

If it makes sense to go into an excel spreadsheet, it probably belongs in a traditional database
If it would normally be stored on your hard drive as its own file, it probably is a "large file"

Large files are interesting because:

They're large in size (duh) and are thus more performance-sensitive
They're usually accessed frequently, and this combined with their size can quickly lead to performance bottlenecks

Assignment

In the root of your repo there is a script called samplesdownload.sh. Run it from the root of the repo to download some sample images and videos into the samples directory:

./samplesdownload.sh

Note that this will download about 60MB of sample files, so depending on your internet connection it might take a second.

Take a look at the boots-image-horizontal.png file in the samples directory: it's a PNG image file. You can open it in an image viewer to see what it looks like.
Use xxd to view a hexdump of the samples/boots-image-horizontal.png file:

xxd <file>

xxd converts the binary content of the file into a human-readable hexadecimal and ASCII formats. You should see a bunch of gobbledegook - that's what a PNG file looks like in its raw form.

Inspect the first 8 bytes of the file more closely. Use xxd with -l (length) to limit the output:

xxd -l 8 <file>

You'll see that the first 8 bytes are 89 50 4e 47 0d 0a 1a 0a, which is the PNG file signature. It tells the reader that this is a PNG file, in fact, the characters PNG are present in bytes 2-4.

Run and submit the CLI tests.