Welcome to Liara’s documentation!

Quickstart

If you want to get rolling with Liara right away, here’s a quickstart guide to get you started.

Installation

Run:

pip install Liara

Create a project

Installing Liara deploys the command-line runner liara, which is your entry point for all future operations. To get started, create a new folder somewhere and run:

liara quickstart

This will deploy the required scaffolding for a super-simple blog, which we’ll use throughout this guide.

Build the site

From the main directory, run liara build to build the site. The site will be generated in an output subdirectory by default.

Preview the site

Run liara serve to run a local web-server which will show the page. You can edit pages and templates while in this mode and hit refresh to see updates. You cannot add/remove content or change meta-data while running the interactive server though.

Exploring the quick-start template

The quickstart produces a bunch of folders and files:

  • content holds the content, which for the quickstart sample consists of a few blog posts. See Content for more details on how to structure the content.
  • templates holds the template files. The quickstart sample uses jinja2 for its templates. default.yaml in that folder contains the default routes for the templates. See Templates for more information on how to use templates.
  • generators contains a sample generator to create new blog posts. See Generators for more information.
  • A few configuration files.

Changelog

2.1.3

  • Fix liara quickstart not working.
  • Fix a bug when fixing up timezones while using the zoneinfo package for timezone data.

2.1.2

  • Deprecate liara.template.Page.meta in favor of liara.template.Page.metadata (which was newly added in this version) for consistency with liara.template.SiteTemplateProxy.metadata.
  • Use the logger in liara serve instead of printing directly to the console for log messages. The default listen URL will be still printed if showing the browser is disabled.
  • Set the Content-Type header in liara serve. This fixes an issue with Chrome/Edge where SVG images whould not work as they were served without a content type.
  • Update jinja2 dependency to 3.0. This provides access to new Jinja2 features like required blocks.
  • Update click dependency to 8.0.

2.1.1

  • Fix plugins not being packaged.

2.1.0

  • Introduce a new plugin system. This moves the has-pending-document command into a new plugin and adds signals to interact with liara’s processing. See Plugins for details.
  • Remove liara.version.version. Use the standard liara.__version__ variable instead, which was already present in earlier versions.

2.0.7

  • Add a server_rule_only option to prevent the creation of redirection nodes and use the redirection paths verbatim.

2.0.6

  • Add has-pending-document to the command line. This will check if there is any content which is filtered by the DateFilter. This is useful for cron-based deploys which try to not rebuild if there are no content changes, as there is no other way to find out if all content in a given revision has been published.

2.0.5

  • Fix liara create-config not working.

2.0.4

  • Add Sqlite3Cache, which allows caching everything into a single file instead of one file per entry.
  • Add a bytecode cache for the Jinja2TemplateRepository.
  • Fix generated nodes not getting generated when using liara serve.
  • Reduce debug spew when stopping liara serve using ^C.

2.0.3

2.0.2

  • Fix a packaging issue.

2.0.1

  • Improve document handling: Documents without a trailing newline are now supported, previously they would cause an error.
  • Improve configuration: Empty configuration files are now supported.
  • Fix list-files requiring a type to be specified.
  • Add exclude().
  • Override base_url when serving locally. This was previously documented to work, but not implemented. As part of this change, set_metadata_item() was added.

2.0

liara 2.0 is a complete rewrite of liara, with no shared code with the 1.x series. liara 2 is now template & content driven, and no longer just a library which simplifies static page generation. Unlike the 1.x series, it is possible to use liara 2 without writing any Python code.

Collections

A collection in liara groups content together into an optionally ordered collection. This grouping is efficient, i.e. iterating a sorted collection does not incur any sorting cost. It is also efficient to look up the next/previous entry in an collection.

Definition

A collection definition consists of three elements:

  • The name
  • The filter – this is an URL pattern which defines all elements that are in this collection.
  • The ordering – optionally specifies how the collection should be ordered. This is a metadata accessor, to access nested fields, separate the individual accesses using .. For instance, date.year will access the date metadata field first, and then the year attribute.

For example:

blog:
  filter: '/blog/**'
  order_by: 'date'

Defines a collection named blog, which contains all elements under /blog, ordered by the date metadata field.

Usage

Collections can be obtained from the Site object using get_collection(). If ordered, get_next_in_collection() and get_previous_in_collection() can be used to provide next/previous links. The other use of collections are Indices.

Configuration

liara is driven through configuration files. The main file is config.yaml, which can reference other configuration files. To get the full default configuration, use liara create-config.

Directory settings

  • content_directory: The root directory for all content. Output paths will be build relative to this folder.
  • resource_directory: The folder containing resources, i.e. SASS or other files that need to get processed before they can be written to the output.
  • static_directory: The folder containing static files, for instance downloads, images, videos etc.
  • output_directory: The output directory.
  • generator_directory: The folder containing Generators.

Build settings

  • build.clean_output: If set to True, the output directory will be deleted on every build.
  • build.cache_directory: The directory where the cache will be stored.
  • build.cache_type: The cache type that should be used. db uses a database cache, which stores everything in a single file, while fs uses one file per cache entry.

Content settings

  • content.filters: Specifies which content filters will be applied while discovering content.
  • template: The template definition to apply to the content.
  • collections: Points to the file containing the collection definitions.
  • feeds: Points to the file containing the feed definitions.
  • indices: Points to the file containing the index definitions.
  • metadata: Points to the file containing the site metadata.
  • relaxed_date_parsing: If enabled, metadata fields named date will be processed twice. By default, liara assumes that date contains a markup-specific date field. If this option is on, and the date field is pointing at a string, liara will try to parse that string into a timestamp.
  • allow_relative_links: Allow the usage of relative links in content files. This has a negative build time impact on any file containing relative links and is thus recommended to be left off.

Other settings

Content

No site would be complete without content. In liara, content is provided in a separate directory, and mirrored into the output. That is, a document placed in content-root/foo/bar.md will be routed to /foo/bar/index.html. The content root can be set in the Configuration.

Documents

The bulk of the content are document nodes – Markdown or Html files which get processed by liara to Html and which get templates applied. liara supports some common Markdown extensions to handle tables and code snippets.

Metadata

Every document in liara must start with a metadata header. A metadata header must contain at least the document title. Metadata can be provided as YAML or TOML. For YAML, use --- as the delimiter, for TOML, use +++. Documents can be empty as long as the metadata is present, so this is a valid document with YAML metadata:

---
title: " This is an example"
---

You cannot mix the delimiters, i.e. using --- to start and +++ to end will result in a failure. Using more characters is also not supported.

Content filters

Some metadata fields in liara are processed by a ContentFilter: date and status. date expects a timestamp, for example:

---
title: "My blog post"
date: 2096-11-22 19:30:56+01:00
---

Documents with a date that lies in the future relative to the time the build is invoked will get filtered by the DateFilter. status can be used to hide content by setting it to private – which in turn will make the StatusFilter filter out the page. The filters can be set up in the Configuration.

Feeds

Feeds provide a global overview over the site or a collection, typically in the form of a sitemap file or a RSS feed.

Definition

A feed definition consists of:

  • The type of the feed to be generated.
  • The output path.
  • An optional limit on the number of elements that will be included in the feed.
  • An optional collection to restrict the feed to.

For example:

rss:
  collection: blog
  path: /rss.xml
  limit: 10
json:
  collection: blog
  path: /feed.json
  limit: 10
sitemap:
  path: /sitemap.xml

This file will generate three feeds, one RSSFeedNode which uses the last 10 posts of the blog collection, one JsonFeedNode with the same configuration, and finally one SitemapXmlFeedNode for the whole site.

Generators

Generators are used to create documents from the command line. Typically, they simplify the creation of metadata fields like date. To create a generator, you need to write some Python code. Place a new file into the generator directory (see Configuration), which has the same name as the document type you want to create. For instance, if you want to use liara create blog-post, you’d create a file named blog-post.py. This file must export a single function generate(site: Site, configuration: Dict[Any, str]) -> pathlib.Path. Invoking liara create <type> will first build the site, and then call the generate script to produce a new document. The function must return the location it stored the document to.

Warning

Generator scripts can execute arbitrary Python code. Be careful when using untrusted code.

Indices

liara can generate indices for Collections, for instance, to create a post archive. This is a two step process – first, a collection needs to be defined, then an index can be built on top of that collection.

Definition

An index definition consists of:

  • The name of the collection that is to be indexed.
  • One or more grouping statements.
  • The output path.

For example:

- collection: 'blog'
  group_by: ['date.year']
  path: '/blog/archive/%1'

This snippet defines a new index which groups based on the metadata field date.year, and produces paths of the form /blog/archive/2017 etc. Multiple group-by fields can be used, in which case the collection will process them in turn. I.e. if grouped by year, month, first, all entries would get grouped by year, and then the entries in each separate year would get grouped by month. This requires two path components %1 and %2 to work, which will be consumed by each group in order.

A special syntax can be used for set-like fields, for instance tags. By adding a leading *, the group gets splatted into separate keys. For example, a page with a metadata field tags with the value a, b, grouped by ['*tags'] and using a path /tags/%1 will be available under both /tags/a and /tags/b.

Usage

Indices can be targeted from Templates. An index node generated from an index will have the references attribute set, which allows iterating over all referenced nodes.

Metadata

The default site metadata consists of:

  • title: The site title.
  • description: A description of the site.
  • base_url: The default URL this page will get deployed to. liara may replace this with a different URL when serving the page locally.
  • language: The language, provided as a language code of the form en-US.
  • copyright: The default content copyright.

Metadata is used throughout liara, for instance, Feeds may use the metadata. It is available through metadata within liara, and via metadata to templates.

Plugins

liara supports plugins to extend the functionality. Plugins are discovered by being available in the liara.plugins namespace. For more details, see:

In practice this means you can provide a plugin by placing it in the liara.plugins namespace. A plugin must export at least one method named register, with no parameters. Here’s an example of a minimal plugin:

def register():
    pass

Of course, a completely empty plugin doesn’t provide any functionality. To hook into liara, you can connect event handlers to signals. The signals are defined in the liara.signals module.

Extending the command line

The command line is special as it needs to get extended at a very early stage – before it’s shown to the user for the first time. To extend the command line, you must use the commandline_prepared signal. liara uses Click as the command line parser, but you cannot import liara’s command line module directly in your module as that would lead to circular includes. The recommendation is to put the commands directly into the registration method as following:

from liara.signals import commandline_prepared
import click

def register():
    commandline_prepared.connect(_register_cli)

def _register_cli(cli):
    from liara.cmdline import pass_environment

    @cli.command()
    @pass_environment
    def my_new_command(env):
        print(env.liara)

Note the use of @pass_environment. This requests Click to pass the liara command line environment as the first parameter, which contains the liara instance. See Environment for more details.

Static routes

Static routes provide redirections so that content is reachable under multiple URLs. The static route file is a simple YAML file with the following structure:

- { src: /source/path, dst: /target/path }

Each entry provides a single redirection. If static routes are configured, RedirectionNode instances are created for any source URL, and additionally, an Apache 2 .htaccess redirection file gets generated. The generation of RedirectionNode instances can be skipped by setting the server_rule_only flag. In that case, the src and dst path will not be normalized either, making it possible to redirect paths like /feed/ (which would otherwise get normalized to /feed.)

Templates

Templates in liara are used to style content. There are two parts to every template, the first is the definition which describes which template should get applied to which URL, and the template execution environment which provides the content that will be consumed by the template.

Definition

Templates are defined using a template definition, which must contain at least two fields:

  • backend chose the template engine, the default is jinja2.
  • paths provides a dictionary containing key-value pairs. The key must be an URL pattern, the value the template file that should get applied for this pattern.

A very basic template could be defined as following:

backend: jinja2
paths:
  "/*": "default.jinja"

This would process any page using the default.jinja template.

Template definitions also support the following fields:

  • static_directory specifies static files which will be deployed to the output. This can be used for images etc.

  • resource_directory specifies resource files to be deployed, for instance SASS files.

  • image_thumbnail_sizes is a dictionary which provides suffixes and the sizes to which images get resized. For instance, assume the following configuration:

    image_thumbnail_sizes:
  thumbnail: {width: 640}

    This will resize any static image file (from the template or the site itself) to a maximum width of 640 pixels. The thumbnail will be stored using the same file path as the original, but with thumbnail added to the suffix. For instance, an input file named foo.png with width 800 would be resized to foo.thumbnail.png with a width of 640. Files which are below the size will get copied, so it’s always safe to use the .thumbnail suffix.

Note

There is nothing special about thumbnail in the example above – any suffix can be used, and multiple suffixes are support.

Authoring Templates

Templates get applied to DocumentNode and IndexNode instances only. Inside a template, a few global variables are pre-populated to provide access to the site and page content. Note that the content of other nodes cannot be referenced inside a template (as the order in which they get executed is unspecified), however, metadata of other nodes is available and can be used.

  • page references the current node, in form of a Page instance.
  • node provides access to the current node directly, which will point to a Node instance.
  • site provides access to the site in form of the SiteTemplateProxy object.

URL patterns

In various places liara allows matching content by URL pattern. This is very similar to matching files using a glob pattern, the syntax is as following:

  • * matches anything but a subpath (i.e., /foo/* will match /foo/bar, but not /foo/bar/baz)
  • ** matches anything recursively (i.e. /foo/** will match any path starting with /foo/)

Perfect matches take precedence over wildcard matches. That is, if there are two URL patterns /foo/* and /foo/, and they are matched against /foo/, both match but /foo/ gets selected as it’s a perfect match.

Additionally, URL patterns allow a query string to restrict the search to specific types. For instance, /foo/**?kind=document will match all DocumentNode below /foo/, but will ignore other node types. The nodes types that can be selected using this method are document for DocumentNode instances and index for IndexNode instances.

Module reference

liara package

liara.actions module

class liara.actions.LinkType

Bases: enum.Enum

An enumeration.

External = 2
Internal = 1

Gather links across documents.

Returns:A dictionary containing a link, and the list of document paths in which this link was found.

Validate external links.

This issues a request for each link, and checks if it connects correctly. If not, an error is printed indicating the link and the documents referencing it.

Validate internal links.

For each link, check if it exists inside the provided site. If not, an error is printed indicating the link and the documents referencing it.

liara.cache module

class liara.cache.Cache

Bases: object

A key-value cache.

contains(key: bytes) → bool

Check if an object is stored.

Parameters:key – The key to check.
Returns:True if such an object exists, else False.
get(key: bytes) → object

Get a stored object.

Parameters:key – The object key.
Returns:An object if one exists. Otherwise, the behavior is undefined. Use contains() to check if an object exists.
put(key: bytes, value: object) → bool

Put a value into the cache using the provided key.

Parameters:
  • key – The key under which value will be stored.
  • value – A pickable Python object to be stored.
Returns:

True if the value was added to the cache, False if it was already cached.
class liara.cache.FilesystemCache(path: pathlib.Path)

Bases: liara.cache.Cache

A Cache implementation which uses the filesystem to cache data.

This cache tries to load a previously generated index. Use persist() to write the cache index to disk.

contains(key: bytes) → bool

Check if an object is stored.

Parameters:key – The key to check.
Returns:True if such an object exists, else False.
get(key: bytes) → object

Get a stored object.

Parameters:key – The object key.
Returns:An object if one exists. Otherwise, the behavior is undefined. Use contains() to check if an object exists.
persist()

Persists this cache to disk.

This function should be called after the cache has been populated. On the next run, the constructor will then pick up the index and return cached data.

put(key: bytes, value: object) → bool

Put a value into the cache using the provided key.

Parameters:
  • key – The key under which value will be stored.
  • value – A pickable Python object to be stored.
Returns:

True if the value was added to the cache, False if it was already cached.
class liara.cache.MemoryCache

Bases: liara.cache.Cache

An in-memory Cache implementation.

This cache stores all objects in-memory.

contains(key: bytes) → bool

Check if an object is stored.

Parameters:key – The key to check.
Returns:True if such an object exists, else False.
get(key: bytes) → object

Get a stored object.

Parameters:key – The object key.
Returns:An object if one exists. Otherwise, the behavior is undefined. Use contains() to check if an object exists.
put(key: bytes, value: object) → bool

Put a value into the cache using the provided key.

Parameters:
  • key – The key under which value will be stored.
  • value – A pickable Python object to be stored.
Returns:

True if the value was added to the cache, False if it was already cached.
class liara.cache.Sqlite3Cache(path: pathlib.Path)

Bases: liara.cache.Cache

A Cache implementation which uses SQLite to store the data. This is mostly useful if creating many files is slow, for instance due to anti-virus software.

This cache tries to load a previously generated index. Use persist() to write the cache index to disk.

contains(key: bytes) → bool

Check if an object is stored.

Parameters:key – The key to check.
Returns:True if such an object exists, else False.
get(key: bytes) → object

Get a stored object.

Parameters:key – The object key.
Returns:An object if one exists. Otherwise, the behavior is undefined. Use contains() to check if an object exists.
persist()

Persists this cache to disk.

This function should be called after the cache has been populated. On the next run, the constructor will then pick up the index and return cached data.

put(key: bytes, value: object) → bool

Put a value into the cache using the provided key.

Parameters:
  • key – The key under which value will be stored.
  • value – A pickable Python object to be stored.
Returns:

True if the value was added to the cache, False if it was already cached.

liara.cmdline module

class liara.cmdline.Environment

Bases: object

The command line environment.

This provides access to global variables that are useful for command line commands, as well as a global liara instance.

liara
liara.cmdline.main()

liara.config module

liara.config.create_default_configuration() → Dict[str, Any]

Creates a dictionary with the default configuration.

liara.config.create_default_metadata() → Dict[str, Any]

Creates a dictionary with the default metadata.

liara.feeds module

class liara.feeds.FeedNode(path)

Bases: liara.nodes.GeneratedNode

class liara.feeds.JsonFeedNode(path, site: liara.site.Site, *, collection='', limit=10)

Bases: liara.feeds.FeedNode

A JSONFeed based feed.

generate()

Generate the content of this node.

After this function has finished, self.content must be populated with the generated content.

class liara.feeds.RSSFeedNode(path, site: liara.site.Site, *, collection='', limit=10)

Bases: liara.feeds.FeedNode

A RSS 2.0 based feed.

generate()

Generate the content of this node.

After this function has finished, self.content must be populated with the generated content.

class liara.feeds.SitemapXmlFeedNode(path, site: liara.site.Site)

Bases: liara.feeds.FeedNode

A Sitemap 0.90 based feed.

generate()

Generate the content of this node.

After this function has finished, self.content must be populated with the generated content.

liara.md module

class liara.md.HeadingLevelFixupExtension(**kwargs)

Bases: markdown.extensions.Extension

Markdown extension for the HeadingLevelFixupProcessor.

extendMarkdown(md)

Add the various proccesors and patterns to the Markdown Instance.

This method must be overriden by every extension.

Keyword arguments:

  • md: The Markdown instance.
  • md_globals: Global variables in the markdown module namespace.
class liara.md.HeadingLevelFixupProcessor(md=None)

Bases: markdown.treeprocessors.Treeprocessor

This processor demotes headings by one level.

By default, Markdown starts headings with <h1>, but in general the title will be provided by a template. This processor replaces each heading with the next-lower heading, and adds a demoted class.

run(root)

Subclasses of Treeprocessor should implement a run method, which takes a root ElementTree. This method can return another ElementTree object, and the existing root ElementTree will be replaced, or it can modify the current tree and return None.

liara.nodes module

class liara.nodes.DataNode(src, path)

Bases: liara.nodes.Node

A data node.

Data nodes consist of a dictionary. This can be used to store arbitrary data as part of a liara.site.Site, and make it available to templates (for instance, a menu structure could go into a data node.)

class liara.nodes.DocumentNode(src, path, metadata_path=None)

Bases: liara.nodes.Node

load()

Load the content of this node.

publish(publisher: liara.nodes.Publisher) → pathlib.Path

Publish this node using the provided publisher.

reload()

Reload this node from disk.

By default, this just forwards to _load().

set_fixups(*, load_fixups, process_fixups) → None

Set the fixups that should be applied to this document node. The fixups should be set before calling load().

Parameters:
  • load_fixups – These functions will be executed before load() returns.
  • process_fixups – These functions will be executed before process() returns.
validate_metadata()
class liara.nodes.DocumentNodeFactory(configuration)

Bases: liara.nodes.NodeFactory

A factory for document nodes.

class liara.nodes.FixupDateTimezone

Bases: object

Set the timezone of the metadata['date'] field to the local timezone if no timezone has been set.

class liara.nodes.GeneratedNode(path, metadata={})

Bases: liara.nodes.Node

generate() → None

Generate the content of this node.

After this function has finished, self.content must be populated with the generated content.

publish(publisher: liara.nodes.Publisher)

Publish this node using the provided publisher.

class liara.nodes.HtmlDocumentNode(src, path, metadata_path=None)

Bases: liara.nodes.DocumentNode

A node representing a Html document.

process(cache: liara.cache.Cache)

Some nodes – resources, documents, etc. need to be processed. As this can be a resource-intense process (for instance, it may require generating images), processing can cache results and has to be called separately instead of being executed as part of some other operation.

By convention this method should populate self.content.

class liara.nodes.IndexNode(path, metadata={})

Bases: liara.nodes.Node

An index node.

Index nodes are created for every folder if there is no _index node present, and from indices. An index node can optionally contain a list of references, in case the referenced nodes by this index are not direct children of this node.

add_reference(node)

Add a reference to an arbitrary node in the site.

publish(publisher) → pathlib.Path

Publish this node using the provided publisher.

references = None

Nodes referenced by this index node.

An index can not rely on using children as those have to be below the path of the parent node. The references list allows to reference nodes elsewhere in the site.

class liara.nodes.MarkdownDocumentNode(src, path, metadata_path=None)

Bases: liara.nodes.DocumentNode

A node representing a Markdown document.

process(cache: liara.cache.Cache)

Some nodes – resources, documents, etc. need to be processed. As this can be a resource-intense process (for instance, it may require generating images), processing can cache results and has to be called separately instead of being executed as part of some other operation.

By convention this method should populate self.content.

class liara.nodes.MetadataKind

Bases: enum.Enum

An enumeration.

Toml = 3
Unknown = 1
Yaml = 2
class liara.nodes.Node

Bases: object

add_child(child: liara.nodes.Node) → None

Add a new child to this node.

The path of the child node must be a sub-path of the current node path, with exactly one more component. I.e. if the current node path is /foo/bar, a node with path /foo/bar/baz can be added as a child, but /baz/ or /foo/bar/boo/baz would be invalid.

children

A list containing all direct children of this node.

get_child(name) → Optional[liara.nodes.Node]

Get a child of this node.

Returns:The child node or None if no such child exists.
get_children(*, recursive=False) → Iterable[liara.nodes.Node]

Get all children of this node.

This function differs from select_children() in two important ways:

  • It returns a list of Node instances and does not wrap it in a Query
  • It can enumerate all children recursively.
kind = None

The node kind, must be set in the constructor.

metadata = None

Metadata associated with this node.

parent = None

The parent node, if any.

path = None

The output path, relative to the page root.

All paths must start with /.

process(cache: liara.cache.Cache) → None

Some nodes – resources, documents, etc. need to be processed. As this can be a resource-intense process (for instance, it may require generating images), processing can cache results and has to be called separately instead of being executed as part of some other operation.

By convention this method should populate self.content.

select_children()

Select all children of this node and return them as a Query.

src = None

The full path to the source file.

This is an OS specific path object.

class liara.nodes.NodeFactory

Bases: typing.Generic

A generic factory for nodes, which builds nodes based on the file type.

create_node(suffix: str, src: pathlib.Path, path: pathlib.PurePosixPath, metadata_path: Optional[pathlib.Path] = None) → T

Create a node using the provided parameters.

known_types
register_type(suffixes: Union[str, Iterable[str]], node_type: type) → None

Register a new node type.

Parameters:
  • suffixes – Either one suffix, or a list of suffixes to be registered for this type. For instance, a node representing an image could be registered to [.jpg, .png].
  • node_type – The type of the node to be created.
class liara.nodes.NodeKind

Bases: enum.Enum

An enumeration.

Data = 4
Document = 3
Generated = 6
Index = 2
Resource = 1
Static = 5
class liara.nodes.Publisher

Bases: object

A publisher produces the final output files, applying templates etc. as needed.

publish_document(document: liara.nodes.DocumentNode)

Publish a document node.

publish_generated(generated: liara.nodes.GeneratedNode)

Publish a generated node.

publish_index(index: liara.nodes.IndexNode)

Publish an index node.

publish_resource(resource: liara.nodes.ResourceNode)

Publish a resource node.

publish_static(static: liara.nodes.StaticNode)

Publish a static node.

class liara.nodes.RedirectionNode(path: pathlib.PurePosixPath, dst: pathlib.PurePosixPath, *, base_url='')

Bases: liara.nodes.GeneratedNode

A redirection node triggers a redirection to another page.

This node gets processed into a simple web site which tries to redirect using both <meta http-equiv="refresh"> and Javascript code setting window.location.

generate()

Generate the content of this node.

After this function has finished, self.content must be populated with the generated content.

class liara.nodes.ResourceNode(src, path, metadata_path=None)

Bases: liara.nodes.Node

A resource node applies some process when creating the output.

This is useful if you have content where the source cannot be interpreted, and requires some process first before it becomes usable – for instance, SASS to CSS compilation.

publish(publisher: liara.nodes.Publisher) → pathlib.Path

Publish this node using the provided publisher.

reload() → None
class liara.nodes.ResourceNodeFactory

Bases: liara.nodes.NodeFactory

A factory for resource nodes.

class liara.nodes.SassResourceNode(src, path, metadata_path=None)

Bases: liara.nodes.ResourceNode

This resource node compiles .sass and .scss files to CSS when built.

process(cache: liara.cache.Cache)

Some nodes – resources, documents, etc. need to be processed. As this can be a resource-intense process (for instance, it may require generating images), processing can cache results and has to be called separately instead of being executed as part of some other operation.

By convention this method should populate self.content.

reload() → None
class liara.nodes.StaticNode(src, path, metadata_path=None)

Bases: liara.nodes.Node

A static data node.

Static nodes are suitable for large static data which never changes, for instance, binary files, videos, images etc.

is_image

Return True if this static file is pointing to an image.

publish(publisher: liara.nodes.Publisher) → pathlib.Path

Publish this node using the provided publisher.

update_metadata() → None

Update metadata by deriving some metadata from the source file, if possible.

For static nodes pointing to images, this will create a new metadata field image_size and populate it with the image resolution.

class liara.nodes.ThumbnailNode(src, path, size)

Bases: liara.nodes.ResourceNode

process(cache: liara.cache.Cache)

Some nodes – resources, documents, etc. need to be processed. As this can be a resource-intense process (for instance, it may require generating images), processing can cache results and has to be called separately instead of being executed as part of some other operation.

By convention this method should populate self.content.

liara.nodes.extract_metadata_content(text: str)

Extract metadata and content.

Metadata is stored at the beginning of the file, separated using a metadata seperation marker, for instance:

+++
this_is_toml = True
+++

content

This function splits the provided text into metadata and actual content.

liara.nodes.fixup_date(document: liara.nodes.DocumentNode)

If the date in the document is a string, try to parse it to produce a datetime object.

Replace relative links in the document with links relative to the site root.

liara.publish module

class liara.publish.DefaultPublisher(output_path: pathlib.Path, site: liara.site.Site)

Bases: liara.nodes.Publisher

publish_generated(generated: liara.nodes.GeneratedNode)

Publish a generated node.

publish_resource(resource: liara.nodes.ResourceNode)

Publish a resource node.

publish_static(static: liara.nodes.StaticNode)

Publish a static node.

class liara.publish.TemplatePublisher(output_path: pathlib.Path, site: liara.site.Site, template_repository: liara.template.TemplateRepository)

Bases: liara.publish.DefaultPublisher

publish_document(document)

Publish a document node.

publish_index(index: liara.nodes.IndexNode)

Publish an index node.

liara.query module

class liara.query.ExcludeFilter(pattern)

Bases: liara.query.SelectionFilter

Filter items by a provided pattern. The pattern is matched against the path. If it matches, the item will be ignored.

match(node: liara.nodes.Node) → bool

Return True if the node should be kept, else False.

class liara.query.MetadataFilter(name, value=None)

Bases: liara.query.SelectionFilter

Filter items which contain a specific metadata field and optionally check if that field matches the provided value.

match(node: liara.nodes.Node) → bool

Return True if the node should be kept, else False.

class liara.query.MetadataSorter(item: str, reverse=False, case_sensitive=False)

Bases: liara.query.Sorter

Sort nodes by metadata.

get_key(item: liara.template.Page)

Return the key to be used for sorting.

class liara.query.Query(nodes)

Bases: collections.abc.Iterable, typing.Generic

A query modifies a list of nodes, by sorting and filtering entries.

exclude(pattern) → liara.query.Query

Exclude nodes matching the provided regex pattern. The pattern will be applied to the full path.

limit(limit) → liara.query.Query

Limit this query to return at most limit results.

reversed() → liara.query.Query

Return the results of this query in reversed order.

sorted_by_date(*, reverse=False) → liara.query.Query

Sort the entries in this query by the metadata field date.

sorted_by_metadata(tag: str, *, reverse=False, case_sensitive=False) → liara.query.Query

Sort the entries in this query by the specified metadata field.

sorted_by_title(*, reverse=False) → liara.query.Query

Sort the entries in this query by the metadata field title.

with_metadata(name, value=None) → liara.query.Query

Limit this query to only include nodes which contain the specific metadata field.

Parameters:value – If value is provided, the field must exist and match the provided value.
with_tag(name) → liara.query.Query

Limit this query to only include nodes with a metadata field named tags which contains the specified tag name.

class liara.query.SelectionFilter

Bases: object

Base class for query selection filters.

match(node: liara.nodes.Node) → bool

Return True if the node should be kept, else False.

class liara.query.Sorter(reverse=False)

Bases: object

Base class for query sorters.

get_key(item)

Return the key to be used for sorting.

reverse

Returns True if the sort order should be reversed.

class liara.query.TagFilter(name)

Bases: liara.query.SelectionFilter

Filter items by a specific tag, this expects a metadata field named tags to be present, and that field must support checks for containment using in.

match(node: liara.nodes.Node) → bool

Return True if the node should be kept, else False.

liara.quickstart module

liara.quickstart.generate()
liara.quickstart.generate_configs()
liara.quickstart.generate_content()
liara.quickstart.generate_css()
liara.quickstart.generate_generator()
liara.quickstart.generate_templates()
liara.quickstart.generate_theme()

liara.server module

class liara.server.HttpServer(site: liara.site.Site, template_repository: liara.template.TemplateRepository, configuration, *, open_browser=True)

Bases: object

static get_url()
port = 8080
serve()

Serve the site with just-in-time processing.

This does not build the whole site up-front, but rather builds nodes on demand. Nodes requiring templates are rebuilt from scratch every time to ensure they’re up-to-date. Adding/removing nodes while serving will break the server, as it will not get notified and re-discover content.

liara.signals module

liara.signals.content_filtered

Raised when content has been removed due to a filter.

Parameters:
liara.signals.content_added

Raised when a content node was successfully added.

Parameters:node (liara.nodes.Node) – the node that was created
liara.signals.commandline_prepared

Raised when the command line parsing environment was prepared.

Parameters:cli (click.group) – The command line group to add commands to.
liara.signals.content_discovered

Raised after all content has been discovered.

Parameters:site (liara.site) – the site instance
liara.signals.documents_processed

Raised after all documents have been processed. Processing includes for instance converting the content from markdown to HTML.

param liara.site site:
 the site instance
liara.signals.document_loaded

Raised after a document has been loaded, before any templates etc. have been applied.

param liara.nodes.DocumentNode document:
 the document node
param str content:
 the raw document contents

liara.site module

class liara.site.Collection(site, pattern, order_by=[])

Bases: object

A collection is a set of nodes. Collections can be ordered, which allows for next/previous queries.

get_next(node)

Get the next node in this collection with regard to the specified order, or None if this is the last node.

get_previous(node)

Get the previous node in this collection with regard to the specified order, or None if this is the first node.

nodes

Get the (sorted) nodes in this collection.

class liara.site.ContentFilter

Bases: object

Content filters can filter out nodes based on various criteria.

apply(node: liara.nodes.Node) → bool

Return True if the node should be kept, and False otherwise.

name
reason

Return a reason why this filter applied.

class liara.site.ContentFilterFactory

Bases: object

create_filter(name: str) → liara.site.ContentFilter
class liara.site.DateFilter

Bases: liara.site.ContentFilter

Filter content based on the metadata field date.

If the date is in the future, the node will be filtered.

apply(node: liara.nodes.Node) → bool

Return True if the node should be kept, and False otherwise.

name
reason

Return a reason why this filter applied.

class liara.site.Index(site, collection: liara.site.Collection, path: str, group_by=[], *, create_top_level_index=False)

Bases: object

An index into a collection, which provides an index structure.

The index structure requires a grouping schema – for instance, all nodes containing some tag can get grouped under one index node.

create_nodes(site)

Create the index nodes inside the specified site.

class liara.site.Site

Bases: object

This class manages to all site content.

add_data(node: liara.nodes.DataNode) → None

Add a data node to this site.

add_document(node: liara.nodes.DocumentNode) → None

Add a document to this site.

add_generated(node: liara.nodes.GeneratedNode) → None

Add a generated node to this site.

add_index(node: liara.nodes.IndexNode) → None

Add an index node to this site.

add_resource(node: liara.nodes.ResourceNode) → None

Add a resource to this site.

add_static(node: liara.nodes.StaticNode) → None

Add a static node to this site.

create_collections(collections)

Create collections.

create_indices(indices)

Create indices.

This creates links between parents/children.

This is a separate step so it can be executed after merging nodes from multiple sources, for instance themes. It is safe to call this function multiple times to create new links; nodes which already have a parent are automatically skipped.

create_thumbnails(thumbnail_definition)

Create thumbnails.

Based on the thumbnail definition – which is assumed to be a dictionary containing the suffix and the desired size – this function iterates over all static nodes that contain images, and creates new thumbnail nodes as required.

data = None

The list of all data nodes in this site.

documents = None

The list of all document nodes in this site.

filtered_content

Return which node paths got filtered and due to which filter.

generated = None

The list of all generated nodes in this site.

get_collection(collection: str) → liara.site.Collection

Get a collection.

get_next_in_collection(collection: str, node: liara.nodes.Node) → Optional[liara.nodes.Node]

Get the next node in a collection.

get_node(path: pathlib.PurePosixPath) → Optional[liara.nodes.Node]

Get a node based on the URL, or None if no such node exists.

get_previous_in_collection(collection: str, node: liara.nodes.Node) → Optional[liara.nodes.Node]

Get the previous node in a collection.

indices = None

The list of all index nodes in this site.

metadata = None

Metadata describing this site.

nodes

The list of all nodes in this site.

register_content_filter(content_filter: liara.site.ContentFilter)

Register a new content filter.

resources = None

The list of all resources nodes in this site.

select(query: str) → Iterable[liara.nodes.Node]

Select nodes from this site.

The query string may contain * to list all direct children of a node, and ** to recursively enumerate nodes. Partial matches using *foo are not supported.

set_metadata(metadata: Dict[str, Any]) → None

Set the metadata for this site.

This overrides any previously set metadata. Metadata is accessible via the metadata attribute.

set_metadata_item(key: str, value: Any) → None

Set a single entry in the metadata for this site.

This can be used to override individual metadata items.

static = None

The list of all static nodes in this site.

urls

The list of all registered URLs.

class liara.site.StatusFilter

Bases: liara.site.ContentFilter

Filter content based on the metadata field status.

If status is set to private, the node will be filtered. The comparison is case-insensitive.

apply(node: liara.nodes.Node) → bool

Return True if the node should be kept, and False otherwise.

name
reason

Return a reason why this filter applied.

liara.template module

class liara.template.Jinja2Template(template)

Bases: liara.template.Template

render(**kwargs) → str
class liara.template.Jinja2TemplateRepository(paths: Dict[str, str], path: pathlib.Path, cache: liara.cache.Cache = None)

Bases: liara.template.TemplateRepository

Jinja2 based template repository.

find_template(url, site: liara.site.Site) → liara.template.Template
class liara.template.MakoTemplate(template)

Bases: liara.template.Template

render(**kwargs) → str
class liara.template.MakoTemplateRepository(paths: Dict[str, str], path: pathlib.Path)

Bases: liara.template.TemplateRepository

find_template(url, site: liara.site.Site) → liara.template.Template
class liara.template.Page(node)

Bases: object

A wrapper around DocumentNode and IndexNode for use inside templates.

Templates only get applied to those node types, and the Page class provides convenience accessors while hiding the underlying node from template code.

content

Provides the content of this page.

meta

Provides the metadata associated with this page.

Deprecated since version 2.1.2: Use metadata instead.

metadata

Provides the metadata associated with this page.

New in version 2.1.2.

references

Provides the list of referenced nodes by this page.

This can be only used if the current page is an IndexNode, in all other cases this will fail. For index nodes, this will return the list of references as a Query instance.

url

Provides the current path of this page.

class liara.template.SiteTemplateProxy(site: liara.site.Site)

Bases: object

A wrapper around Site for use inside templates.

data

Get the union of all liara.nodes.DataNode instances in this site.

get_collection(collection: str) → query.Query

Get a collection in form of a liara.query.Query for further filtering/sorting.

get_next_in_collection(collection: str, page: liara.template.Page) → Optional[liara.template.Page]

Given a collection and a page, return the next page in this collection or None if this is the last page.

get_page_by_url(url) → Optional[liara.template.Page]

Return a page by URL. If the page cannot be found, return None.

get_previous_in_collection(collection: str, page: liara.template.Page) → Optional[liara.template.Page]

Given a collection and a page, return the previous page in this collection or None if this is the first page.

metadata

Provide access to the metadata of this site.

select(query) → query.Query

Run a query on this site.

class liara.template.Template

Bases: object

render(**kwargs)
class liara.template.TemplateRepository(paths: Dict[str, str])

Bases: object

find_template(url: str) → liara.template.Template
update_paths(paths: Dict[str, str])

liara.util module

liara.util.add_suffix(path: pathlib.Path, suffix)

Add a suffix to a path.

This differs from with_suffix by adding a suffix without changing the extension, i.e. adding en to foo.baz will produce foo.en.baz.

liara.util.create_slug(s: str) → str

Convert a plain string into a slug.

A slug is suitable for use as a URL. For instance, passing A new world to this function will return a-new-world.

liara.util.flatten_dictionary(d, sep='.', parent_key=None)

Flatten a nested dictionary. This uses the separator to combine keys together, so a dictionary access like ['a']['b'] with a separator '.' turns into 'a.b'.

liara.util.local_now() → datetime.datetime

Get a timezone aware timestamp.

This is equivalent to datetime.datetime.now(), except it returns a timestamp which has tzinfo set to the local timezone.

liara.util.pairwise(iterable)

For a list s, return pairs for consecutive entries. For example, a list s0, s1, etc. will produce (s0,s1), (s1,s2), ... and so on.

See: https://docs.python.org/3/library/itertools.html#recipes.

liara.util.readtime(wordcount: int, words_per_minute=300)

Given a number of words, estimate the time it would take to read them.

Returns:The time in minutes if it’s more than 1, otherwise 1.

liara.yaml module

liara.yaml.dump_yaml(data, stream=None)

Dump an object to Yaml.

This is a helper function which tries to use the fast CDumper implementation and falls back to the native Python version on failure.

liara.yaml.load_yaml(s)

Load a Yaml document.

This is a helper function which tries to use the fast CLoader implementation and falls back to the native Python version on failure.

Module contents

class liara.Liara(configuration=None, *, configuration_overrides={})

Main entry point for Liara. This class handles all the state required to process and build a site.

build(discover_content=True)

Build the site.

Parameters:discover_content (bool) – If True, discover_content() will be called first.
create_document(t)

Create a new document using a generator.

discover_content() → liara.site.Site

Discover all content and build the liara.site.Site instance.

serve(*, open_browser=True)

Serve the current site using a local webserver.

Indices and tables