# mirror-img

[mirror-img](https://hak.xwx.moe/jadedctrl/mirror-img) is a command-line tool that creates a “local” version of an HTML
file, mirroring its remote images, stylesheets, and other resources.


## Usage
```
usage: mirror-img [-h] [-d DIR] [-b BASE] [-s URL] HTML_FILE
       mirror-img [-h] [-d DIR] [-b BASE] [-s URL]
Available options:
  -h, --help          print this help text.
  -b, --base ARG      path to mirror directory used in URLs
  -s, --source ARG    URL used to resolve & mirror relative URLs
  -d, --downloads ARG directory for all mirrored files
```

### Examples
In order to mirror a webpage, you can simply download it and pipe it into mirror-img:

```
$ curl https://www.gnu.org/philosophy/philosophy.html | mirror-img > philosophy.html
```

And now `philosophy.html` is a fully-local HTML file with no external resources!

… at least, it *would* be. Notice how some resources, like the CSS, don’t load.
This is because they are defined as *relative* links (e.g., “../style.css”
rather than “https://invalid.tld/style.css”). In order for these to be
mirrored as well, mirror-img needs to somehow know the source URL.

You can use the `--source` argument to provide the source URL, so
relatively-linked resources can be mirrored, too:

```
$ SOURCE_URL="https://www.gnu.org/philosophy/philosophy.html"
$ curl "$SOURCE_URL" | mirror-img --source "$SOURCE_URL" > philosophy.html
```

*Now* we’re done! All mirrored content will be found in the `mirror/`
directory, and all links have been adjusted accordingly.

---

If you’d like to change the download directory, you can use the `--downloads`
argument. To change the directory used in the output-HTML’s URLs, you can
use `--base`.

For example, if you’d like to mirror files into `/tmp/mirrors/` but have URLs
start with `mirrors/` rather than `/tmp/mirrors`:

```
$ mirror-img --base "mirrors/" --downloads /tmp/mirrors/ index.html > new-index.html
```

… now new-index.html contains that local version of index.html!


## Installation
Making a binary requires [an implementation](https://common-lisp.net/implementations) of Common Lisp installed:
[Steel Bank Common Lisp](https://sbcl.org/) is our implementation-of-choice. It’s available on
most operating systems under the package name `sbcl`.

You also need the library-manager [Quicklisp](https://quicklisp.org), which can [be installed](https://www.quicklisp.org/beta/#installation)
quite easily, including via our [Makefile](Makefile).

To install Quicklisp, build a binary, and install it, simply:

```
$ make quicklisp
$ make build
$ sudo cp mirror-img /usr/local/bin/mirror-img
```

Bam, you've made and installed a binary! Cool!

### Tests
mirror-img’s tests can be run from a REPL using `ASDF:TEST-SYSTEM`, or from the
Makefile target “test”.

```
* (asdf:test-system :eksd)
* (asdf:test-system :eksd/unix)
```

```
$ make test
```


## Misc
* License is the GNU GPLv3 ([COPYING.txt](COPYING.txt))
* Author is Jaidyn Ann <jadedctrl@posteo.at>
* Source is at https://hak.xwx.moe/jadedctrl/mirror-img