Merge pull request #1544 from joshrotenberg/guide_configuration_restructure

Restructure guide configuration section

Author: ehuss

guide/book.toml

@@ -25,3 +25,6 @@ boost-hierarchy = 2
 boost-paragraph = 1
 expand = true
 heading-split-level = 2
+
+[output.html.redirect]
+"/format/config.html" = "configuration/index.html"

guide/src/SUMMARY.md

@@ -11,7 +11,11 @@
 - [Format](format/README.md)
     - [SUMMARY.md](format/summary.md)
         - [Draft chapter]()
-    - [Configuration](format/config.md)
+    - [Configuration](format/configuration/README.md)
+        - [General](format/configuration/general.md)
+        - [Preprocessors](format/configuration/preprocessors.md)
+        - [Renderers](format/configuration/renderers.md)
+        - [Environment Variables](format/configuration/environment-variables.md)
     - [Theme](format/theme/README.md)
         - [index.hbs](format/theme/index-hbs.md)
         - [Syntax highlighting](format/theme/syntax-highlighting.md)

guide/src/format/configuration/README.md

@@ -0,0 +1,12 @@
+# Configuration
+
+This section details the configuration options available in the ***book.toml***:
+- **[General]** configuration including the `book`, `rust`, `build` sections
+- **[Preprocessor]** configuration for default and custom book preprocessors
+- **[Renderer]** configuration for the HTML, Markdown and custom renderers
+- **[Environment Variable]** configuration for overriding configuration options in your environment
+
+[General]: general.md
+[Preprocessor]: preprocessors.md
+[Renderer]: renderers.md
+[Environment Variable]: environment-variables.md

guide/src/format/configuration/environment-variables.md

@@ -0,0 +1,38 @@
+# Environment Variables
+
+All configuration values can be overridden from the command line by setting the
+corresponding environment variable. Because many operating systems restrict
+environment variables to be alphanumeric characters or `_`, the configuration
+key needs to be formatted slightly differently to the normal `foo.bar.baz` form.
+
+Variables starting with `MDBOOK_` are used for configuration. The key is created
+by removing the `MDBOOK_` prefix and turning the resulting string into
+`kebab-case`. Double underscores (`__`) separate nested keys, while a single
+underscore (`_`) is replaced with a dash (`-`).
+
+For example:
+
+- `MDBOOK_foo` -> `foo`
+- `MDBOOK_FOO` -> `foo`
+- `MDBOOK_FOO__BAR` -> `foo.bar`
+- `MDBOOK_FOO_BAR` -> `foo-bar`
+- `MDBOOK_FOO_bar__baz` -> `foo-bar.baz`
+
+So by setting the `MDBOOK_BOOK__TITLE` environment variable you can override the
+book's title without needing to touch your `book.toml`.
+
+> **Note:** To facilitate setting more complex config items, the value of an
+> environment variable is first parsed as JSON, falling back to a string if the
+> parse fails.
+>
+> This means, if you so desired, you could override all book metadata when
+> building the book with something like
+>
+> ```shell
+> $ export MDBOOK_BOOK="{'title': 'My Awesome Book', authors: ['Michael-F-Bryan']}"
+> $ mdbook build
+> ```
+
+The latter case may be useful in situations where `mdbook` is invoked from a
+script or CI, where it sometimes isn't possible to update the `book.toml` before
+building.

guide/src/format/configuration/general.md

@@ -0,0 +1,97 @@
+# General Configuration
+
+You can configure the parameters for your book in the ***book.toml*** file.
+
+Here is an example of what a ***book.toml*** file might look like:
+
+```toml
+[book]
+title = "Example book"
+author = "John Doe"
+description = "The example book covers examples."
+
+[rust]
+edition = "2018"
+
+[build]
+build-dir = "my-example-book"
+create-missing = false
+
+[preprocessor.index]
+
+[preprocessor.links]
+
+[output.html]
+additional-css = ["custom.css"]
+
+[output.html.search]
+limit-results = 15
+```
+
+## Supported configuration options
+
+It is important to note that **any** relative path specified in the
+configuration will always be taken relative from the root of the book where the
+configuration file is located.
+
+### General metadata
+
+This is general information about your book.
+
+- **title:** The title of the book
+- **authors:** The author(s) of the book
+- **description:** A description for the book, which is added as meta
+  information in the html `<head>` of each page
+- **src:** By default, the source directory is found in the directory named
+  `src` directly under the root folder. But this is configurable with the `src`
+  key in the configuration file.
+- **language:** The main language of the book, which is used as a language attribute `<html lang="en">` for example.
+
+**book.toml**
+```toml
+[book]
+title = "Example book"
+authors = ["John Doe", "Jane Doe"]
+description = "The example book covers examples."
+src = "my-src"  # the source files will be found in `root/my-src` instead of `root/src`
+language = "en"
+```
+
+### Rust options
+
+Options for the Rust language, relevant to running tests and playground
+integration.
+
+- **edition**: Rust edition to use by default for the code snippets. Default
+  is "2015". Individual code blocks can be controlled with the `edition2015`
+  or `edition2018` annotations, such as:
+
+  ~~~text
+  ```rust,edition2015
+  // This only works in 2015.
+  let try = true;
+  ```
+  ~~~
+
+### Build options
+
+This controls the build process of your book.
+
+- **build-dir:** The directory to put the rendered book in. By default this is
+  `book/` in the book's root directory.
+- **create-missing:** By default, any missing files specified in `SUMMARY.md`
+  will be created when the book is built (i.e. `create-missing = true`). If this
+  is `false` then the build process will instead exit with an error if any files
+  do not exist.
+- **use-default-preprocessors:** Disable the default preprocessors of (`links` &
+  `index`) by setting this option to `false`.
+
+  If you have the same, and/or other preprocessors declared via their table
+  of configuration, they will run instead.
+
+  - For clarity, with no preprocessor configuration, the default `links` and
+    `index` will run.
+  - Setting `use-default-preprocessors = false` will disable these
+    default preprocessors from running.
+  - Adding `[preprocessor.links]`, for example, will ensure, regardless of
+    `use-default-preprocessors` that `links` it will run.

guide/src/format/configuration/preprocessors.md

@@ -0,0 +1,58 @@
+# Configuring Preprocessors
+
+The following preprocessors are available and included by default:
+
+- `links`: Expand the `{{ #playground }}`, `{{ #include }}`, and `{{ #rustdoc_include }}` handlebars
+  helpers in a chapter to include the contents of a file.
+- `index`: Convert all chapter files named `README.md` into `index.md`. That is
+  to say, all `README.md` would be rendered to an index file `index.html` in the
+  rendered book.
+
+
+**book.toml**
+```toml
+[build]
+build-dir = "build"
+create-missing = false
+
+[preprocessor.links]
+
+[preprocessor.index]
+```
+
+### Custom Preprocessor Configuration
+
+Like renderers, preprocessor will need to be given its own table (e.g.
+`[preprocessor.mathjax]`). In the section, you may then pass extra
+configuration to the preprocessor by adding key-value pairs to the table.
+
+For example
+
+```toml
+[preprocessor.links]
+# set the renderers this preprocessor will run for
+renderers = ["html"]
+some_extra_feature = true
+```
+
+#### Locking a Preprocessor dependency to a renderer
+
+You can explicitly specify that a preprocessor should run for a renderer by
+binding the two together.
+
+```toml
+[preprocessor.mathjax]
+renderers = ["html"]  # mathjax only makes sense with the HTML renderer
+```
+
+### Provide Your Own Command
+
+By default when you add a `[preprocessor.foo]` table to your `book.toml` file,
+`mdbook` will try to invoke the `mdbook-foo` executable. If you want to use a
+different program name or pass in command-line arguments, this behaviour can
+be overridden by adding a `command` field.
+
+```toml
+[preprocessor.random]
+command = "python random.py"
+```