Introduction
First off, this document is for the advanced characters. A working knowledge of python is required,
as well as a cursory knowledge of iPhoto and WebExport. You should probably read the
user's guide as well as the developer's guide.
Starting off, there are three phases to a WebExport: preflight, export, postflight. Preflight sets up the
export directory for export. It copies in the template folder's contents, saves the attributes.kvf, properties.kvf
and metadata.tdf files. Then the export phase comes in, uses whatever information given to it by the three files,
and creates a bunch of HTML files. Then, it uses sys.stdout
to relay image creation information to iPhoto. This looks like the example to the right.
The Export Process and Creating Images
exporter.py (std-out)
0 200 150 fill images/thumb/image1.jpg
0 400 300 nice images/med/image1.jpg
0 0 0 nice images/full/image1.jpg
1 200 150 fill images/thumb/image1.jpg
1 400 300 nice images/med/image1.jpg
1 0 0 nice images/full/image1.jpg
The gray line on top is not in the actual output and is here merely for help identifying columns.
The first three columns are easy, first is the index of the image starting at zero (0). Next is the
target width and height. How to get there depends on if you have selected nice (default)
or fill. nice makes the image
(maintaining aspect and without clipping) as big as it can without overflowing the bounds (you can access the size of the produced
image with the width(twidth,theight) and
height(twidth,theight) commands).
fill
on the other hand, fits as much of the image as it can into the given rectangle, but will fill every pixel of the target area.
This option is the fourth option of the image() function.
The last column, the path, is simply the destination file relative to destination directory. It can include "../" paths.
The Beautiful Backend
The backend of WebExport, exporter.py, is a very clean and concise python document located
here.
You can check it out at your leasure, and feel free to come up with clever ways of using it. If you run it on
its own, it does close to nothing. It loads various libraries, reads in the supporting files that are provided
at preflight, and then returns. This is because it executes its arguments as commands evaluated by
exec() For more information about
exec() and eval()
check out the python documentation.
Info.plist
Basically exec() simply executes the given code, and eval() returns the value of what it executes.
If not supplied with an Info.plist, WebExport executes the gen_galleries()
command, which is generally what you want to do.
If you want to only have a certain number of photos per gallery, pass in that number, like this:
gen_galleries(10).
If it does have an Info.plist, it runs every value in an array named "process" as a command. It does not have to be something boring like
gen_galleries, you can also link to other files, process arbitrary files, and more! You can also put a similar array called "postprocess"
in the Info.plist, which will execute after the images are created.
Backend Variables and Accessors
Backend Variables
type
name
description
bool
is_photo
On a photo or gallery
str
title
Image/Gallery Title
str
_title
Gallery title
str
file
Photo Filename
str
author
Image/Gallery Author
str
_author
Gallery author
str
keywords
Image keywords
str
comment
Image/gallery comment
str
_comment
Gallery comment
str
rating
0-5 star photo rating
int
p_index
Current photo index
int
p_count
Total photo count
int
g_index
Current gallery index
range
g_prange
Range of photos associated with this gallery
int
g_count
Total gallery count
str
gallery
Always links to current gallery
You already know about many of these variables, like title.
There are more variables like this, and they are enumerated here. These
are accessible directly from anywhere. You can access any metadata by
using the metadata(name,index)
function, which takes the name of the column, and optionally the index
of the photo you want to pull it from. To access site-wide attributes,
you use the attribute(name)
function, which only takes one argument. To access template properties,
simply use property(name). These
functions respond differently do bad things, like the lack of metadata,
but for more information, check the exporter code out.
Conditionals
closeup.html
...
<if "has_next()">
<a href="<?next()?>">next</a><br/>
<else/>
next
</if>
<if "has_prev()">
<a href="<?prev()?>">prev</a><br/>
<else/>
prev
</if>
...
Conditionals are a very powerful tool, that allow you to execute all kinds of new functionality. In the
developer's guide we talked about the how to link between closeup pages. Well, check this out:
Looking at <if "has_next()">, it seems like an
HTML tag, but there is no such tag, so I've co-opted it for WebExport conditionals. Basically if the code, in this case
has_next(), evaluates true, it processes the blocked-off code between
<if> and </if>.
You can also insert an <else/> which separates
another chunk of code to be executed only if the conditional evaluates false. You could also pull some fancier tricks,
like seeing if p_index is even or odd...
Some Useful Commands
These commands are accessible from anywhere in any python block in your template. They are also accessible in any process/postprocess
commands in the Info.plist.
attribute(key)
| returns | The value for the key, "!NOATTR!" if it does not exist. |
| key | The key from the website attributes file/editor |
date(format="%a, %d %b %Y %H:%M:%S",index):
| returns | The formatted date associated with the photo. |
| format | Python-style date formatting string. |
| index | Index of the photo to pull date info from, defaults to p_index. |
deb(str):
| returns | Nothing. |
| str | String to be logged to stderr (only in debug mode) |
image(maxw,maxh,destination="",style="nice",index=p_index):
| returns | A relative URL to the file produced |
| maxw | Target width of the result image. |
| maxh | Target height of the result image. |
| destination | Relative path to prefix the file with. Can be anything, including ../and other interesting combinations. If the last character is a / it will put the result in a directory, if it is not, it will prefix the filename. |
| style | Either "fill", which fills the entire given space, or "nice" (default) which fits the image nicely into the given space. |
| index | Index of the image you are creating, defaults to the current image. |
link_page(dest,template):
| returns | Link to destination page. |
| dest | Destination path (full URL). |
| source | Template path for process(). |
log(str):
| returns | Nothing. |
| str | String to be logged to stderr (for error use) |
metadata(key,index):
| returns | The metadata value for the key, throws error if it does not exist. |
| key | The metadata key, title, author, comment, etc. Can be customized. |
| index | Index of the photo, defaults to p_index. |
process(code):
| returns | code processed for conditionals, evals, and execs. Used to process every scrap of template. Safe for recursive use. |
| code | Code to be processed. |
processFile(dest,source):
| returns | Nothing. |
| dest | Destination filepath |
| source | Source filepath for process(): |
property(key):
| returns | The value for the key, logs to stderr if it does not exist. |
| key | The key from the template's Info.plist file |