This commit adds support for theme composition and inheritance in Hugo.
With this, it helps thinking about a theme as a set of ordered components:
```toml
theme = ["my-shortcodes", "base-theme", "hyde"]
```
The theme definition example above in `config.toml` creates a theme with the 3 components with presedence from left to right.
So, Hugo will, for any given file, data entry etc., look first in the project, and then in `my-shortcode`, `base-theme` and lastly `hyde`.
Hugo uses two different algorithms to merge the filesystems, depending on the file type:
* For `i18n` and `data` files, Hugo merges deeply using the translation id and data key inside the files.
* For `static`, `layouts` (templates) and `archetypes` files, these are merged on file level. So the left-most file will be chosen.
The name used in the `theme` definition above must match a folder in `/your-site/themes`, e.g. `/your-site/themes/my-shortcodes`. There are plans to improve on this and get a URL scheme so this can be resolved automatically.
Also note that a component that is part of a theme can have its own configuration file, e.g. `config.toml`. There are currently some restrictions to what a theme component can configure:
* `params` (global and per language)
* `menu` (global and per language)
* `outputformats` and `mediatypes`
The same rules apply here: The left-most param/menu etc. with the same ID will win. There are some hidden and experimental namespace support in the above, which we will work to improve in the future, but theme authors are encouraged to create their own namespaces to avoid naming conflicts.
A final note: Themes/components can also have a `theme` definition in their `config.toml` and similar, which is the "inheritance" part of this commit's title. This is currently not supported by the Hugo theme site. We will have to wait for some "auto dependency" feature to be implemented for that to happen, but this can be a powerful feature if you want to create your own theme-variant based on others.
Fixes#4460Fixes#4450
A sample config:
```toml
defaultContentLanguage = "en"
defaultContentLanguageInSubdir = true
[Languages]
[Languages.en]
weight = 10
title = "In English"
languageName = "English"
contentDir = "content/english"
[Languages.nn]
weight = 20
title = "På Norsk"
languageName = "Norsk"
contentDir = "content/norwegian"
```
The value of `contentDir` can be any valid path, even absolute path references. The only restriction is that the content dirs cannot overlap.
The content files will be assigned a language by
1. The placement: `content/norwegian/post/my-post.md` will be read as Norwegian content.
2. The filename: `content/english/post/my-post.nn.md` will be read as Norwegian even if it lives in the English content folder.
The content directories will be merged into a big virtual filesystem with one simple rule: The most specific language file will win.
This means that if both `content/norwegian/post/my-post.md` and `content/english/post/my-post.nn.md` exists, they will be considered duplicates and the version inside `content/norwegian` will win.
Note that translations will be automatically assigned by Hugo by the content file's relative placement, so `content/norwegian/post/my-post.md` will be a translation of `content/english/post/my-post.md`.
If this does not work for you, you can connect the translations together by setting a `translationKey` in the content files' front matter.
Fixes#4523Fixes#4552Fixes#4553
This commit completes the "The Revival of the Archetypes!"
If `.Site` is used in the arcetype template, the site is built and added to the template context.
Note that this may be potentially time consuming for big sites.
A more complete example would then be for the section `newsletter` and the archetype file `archetypes/newsletter.md`:
```
---
title: "{{ replace .TranslationBaseName "-" " " | title }}"
date: {{ .Date }}
tags:
- x
categories:
- x
draft: true
---
<!--more-->
{{ range first 10 ( where .Site.RegularPages "Type" "cool" ) }}
* {{ .Title }}
{{ end }}
```
And then create a new post with:
```bash
hugo new newsletter/the-latest-cool.stuff.md
```
**Hot Tip:** If you set the `newContentEditor` configuration variable to an editor on your `PATH`, the newly created article will be opened.
The above _newsletter type archetype_ illustrates the possibilities: The full Hugo `.Site` and all of Hugo's template funcs can be used in the archetype file.
Fixes#1629
This commit removes the fragile front matter decoding, and takes the provided archetype file as-is and processes it as a template.
This also means that we no longer will attempt to fill in default values for `title` and `date`.
The upside is that it is now easy to create these values in a dynamic way:
```toml
+++
title = {{ .BaseFileName | title }}
date = {{ .Date }}
draft = true
+++
```
You can currently use all of Hugo's template funcs, but the data context is currently very shallow:
* `.Type` gives the archetype kind provided
* `.Name` gives the target file name without extension.
* `.Path` gives the target file name
* `.Date` gives the current time as RFC3339 formatted string
The above will probably be extended in #1629.
Fixes#452
Updates #1629
All config variables starts with low-case and uses camelCase.
If there is abbreviation at the beginning of the name, the whole
abbreviation will be written in low-case.
If there is abbreviation at the end of the name, the
whole abbreviation will be written in upper-case.
For example, rssURI.
This also includes a refactor of the hugofs package and its usage.
The motivation for that is:
The Afero filesystems are brilliant. Hugo's way of adding a dozen of global variables for the different filesystems was a mistake. In readFile (and also in some other places in Hugo today) we need a way to restrict the access inside the working dir. We could use ioutil.ReadFile and implement the path checking, checking the base path and the dots ("..") etc. But it is obviously better to use an Afero BasePathFs combined witha ReadOnlyFs. We could create a use-once-filesystem and handle the initialization ourselves, but since this is also useful to others and the initialization depends on some other global state (which would mean to create a new file system on every invocation), we might as well do it properly and encapsulate the predefined set of filesystems. This change also leads the way, if needed, to encapsulate the file systems in a struct, making it possible to have several file system sets in action at once (parallel multilanguage site building? With Moore's law and all...)
Fixes#1551
NewContent is refactored to use the afero.Fs interface that should allow
full testing. This commit also pulls the metadata creation logic out of
NewContent and into a separate function to decrease the cyclomatic
complexity of NewContent.
