minetest_doc/API.md

API documentation for version 0.5.0

Core concepts

As a modder, you are free to write basically about everything and are also relatively free in the presentation of information. The Documentation System has no restrictions on content whatsoever.

Categories and entries

In the documentation system, everything is built on categories and entries. An entry is a single piece of documentation and is the basis of all actual documentation. Categories group multiple entries of the same topic together.

Categories also define a template which is used to determine how the final result in the Entry tab looks like. Entries themselves have a data field attached to them, this is a table containing arbitrary metadata which is used to construct the final formspec which is used on the Entry tab.

Advanced concepts

Viewed and hidden entries

The mod keeps track of which entries have been viewed by any player. Any entry which has been accessed by a player is instantly marked as “viewed”.

It also allows entries to be hidden. Hidden entries are not visible or normally accessible to players until they become revealed by function calls.

Marking an entry as viewed or revealed is not reversible with this API. The viewed and hidden states are stored in the file doc.mt inside the world directory.

Entry aliases

Entry aliases are alternative identifiers for entry identifiers. With the exception of the alias functions themselves, When a function demands an entry_id you can either supply the original entry_id or any alias of the entry_id.

Possible use cases

I present to you some possible use cases to give you a rough idea what this mod is capable and how certain use casescould be implemented.

Simple use case: Minetest basics

I want to write in freeform short help texts about the basic concepts of Minetest or my subgame. First I define a category called “Basics”, the data for each of its entry is just a freeform text. The template function simply creates a formspec where this freeform text is displayed.

Complex use case: Blocks

I could create a category called “Blocks”, and this category is supposed to contain entries for every single block in the game. For this case, a freeform approach would be very inefficient and error-prone, as a lot of data can be reused.

Here the template function comes in handy: The internal entry data contain a lot of different things about a block, like block name, identifier, custom description and most importantly, the definition table of the block.

Finally, the template function takes all that data and turns it into sentences which are just concatenated, telling as many useful facts about this block as possible.

Functions

This is a list of all publicly available functions.

Overview

The most important functions are doc.new_category and doc.new_entry. All other functions are mostly used for utility and examination purposes.

These functions are available:

• doc.new_category: Adds a new category
• doc.new_entry: Adds a new entry
• doc.show_entry: Shows a particular entry to a player
• doc.show_category: Shows the entry list of a category to a player
• doc.show_doc: Opens the main Documentation System form for a player
• doc.get_category_definition: Returns the definition table of a category
• doc.get_entry_definition: Returns the definition table of an entry
• doc.entry_exists: Checks whether an entry exists
• doc.entry_viewed: Checks whether an entry has been viewed/read by a player
• doc.entry_revealed: Checks whether an entry is visible and normally accessible to a player
• doc.mark_entry_as_viewed: Manually marks an entry as viewed/read by a player
• doc.mark_entry_as_revealed: Make a hidden entry visible and accessible to a player
• doc.add_entry_alias: Add an alternative name which can be used to access an entry
• doc.add_entry_aliases: Add multiple alternative names which can be used to access an entry
• doc.get_category_count: Returns the total number categories
• doc.get_entry_count: Returns the total number of entries in a category
• doc.get_viewed_count: Returns the number of entries a player has viewed in a category
• doc.get_revealed_count: Returns the number of entries a player has access to in a category
• doc.get_hidden_count: Returns the number of entries which are hidden from a player in a category

doc.new_category(id, def)

Adds a new category. You have to define an unique identifier, a name and a template function to build the entry formspec from the entry data.

Important: You must call this function before any player joins, but not later.

Parameters

• id: Unique category identifier as a string
• def: Definition table, it has the following fields:
  • name: Category name to be shown in the interface
  • description: (optional) Short description of the category, will be shown as tooltip. Recommended style (in English): First letter capitalized, no puncation at end of sentence, max. 100 characters
  • build_formspec: The template function. Takes entry data as its only parameter (has the data type of the entry data) and must return a formspec which is inserted in the Entry tab.
  • sorting: (optional) Sorting algorithm for display order of entries
    • "abc": Alphabetical (default)
    • "nosort": Entries appear in no particular order
    • "custom": Manually define the order of entries in sorting_data
    • "function": Sort by function defined in sorting_data
  • sorting_data: (optional) Additional data for special sorting methods.
    • If sorting=="custom", this field must contain a table (list form) in which the entry IDs are specified in the order they are supposed to appear in the entry list. All entries which are missing in this table will appear in no particular order below the final specified one.
    • If sorting=="function", this field is a compare function to be used as the comp parameter of table.sort. The parameters given are two entries.
    • This field is not required if sorting has any other value
  • hide_entries_by_default (optional, experimental): If true, all entries added to this category will start as hidden, unless explicitly specified otherwise (default: false)

Note: For function-based sorting, the entries provided in the compare function have the following format:

{
    name = n, -- entry name
    data = d, -- arbitrary entry data
}

Using build_formspec

For build_formspec you can either define your own function which procedurally generates the entry formspec or you use one of the following predefined convenience functions:

• doc.entry_builders.text: Expects entry data to be a string. It will be inserted directly into the entry. Useful for entries with a freeform text.
• doc.entry_builders.formspec: Entry data is expected to contain the complete entry formspec as a string. Useful if your entries. Useful if you expect your entries to differ wildly in layouts.

When building your formspec, you have to respect the size limitations. The documentation system uses a size of 12,9 and you should place all your formspec elements at positions not lower than 0.25,0.5 to avoid overlapping.

Return value

Always nil.

doc.new_entry(category_id, entry_id, def)

Adds a new entry into an existing category. You have to define the category to which to insert the entry, the entry's identifier, a name and some data which defines the entry. Note you do not directly define here how the end result of an entry looks like, this is done by build_formspec from the category definition.

Important: You must call this function before any player joins, but not later.

Parameters

• category_id: Identifier of the category to add the entry into
• entry_id: Unique identifier of the new entry, as a string
• def: Definition table, it has the following fields:
  • name: Entry name to be shown in the interface
  • hidden: (optional) If true, entry will not be displayed in entry list initially (default: false); it can be revealed later
  • data: Arbitrary data attached to the entry. Any data type is allowed; The data in this field will be used to create the actual formspec with build_formspec from the category definition

Return value

Always nil.

function doc.show_doc(playername)

Opens the main documentation formspec for the player (Main tab).

Parameters

• playername: Name of the player to show the formspec to

doc.show_category(playername, category_id)

Opens the documentation formspec for the player at the specified category (Category tab).

Parameters

• playername: Name of the player to show the formspec to
• category_id: Category identifier of the selected category

Return value

Always nil.

doc.show_entry(playername, category_id, entry_id, ignore_hidden)

Opens the documentation formspec for the player showing the specified entry of a category (Entry tab). If the entry is hidden, an error message is displayed unless ignore_hidden==true.

Parameters

• playername: Name of the player to show the formspec to
• category_id: Category identifier of the selected category
• entry_id: Entry identifier of the entry to show
• ignore_hidden: (optional) If true, shows entry even if it is still hidden to the player; this will automatically reveal the entry to this player for the rest of the game

Return value

Always nil.

doc.get_category_definition(category_id)

Returns the definition of the specified category.

Parameters

• category_id: Category identifier of the category to the the definition for

Return value

The category's definition table as spefied in the def argument of doc.new_category. The table fields are the same.

doc.get_entry_definition(category_id, entry_id)

Returns the definition of the specified entry.

Parameters

• category_id: Category identifier of entry's category
• entry_id: Entry identifier of the entry to get the definition for

Return value

The entry's definition table as spefied in the def argument of doc.new_entry. The table fields are the same.

doc.entry_exists(category_id, entry_id)

Checks if the specified entry exists and returns true or false.

Parameters

• category_id: Category identifier of the category to check
• entry_id: Entry identifier of the entry to check for its existance

Return value

Returns true if and only if:

• The specified category exists
• This category contains the specified entry

Otherwise, returns false.

doc.entry_viewed(playername, category_id, entry_id)

Tells whether the specified entry is marked as “viewed” (or read) by the player.

Parameters

• playername: Name of the player to check
• category_id: Category identifier of the category to check
• entry_id: Entry identifier of the entry to check

Return value

true, if entry is viewed, false otherwise.

doc.entry_revealed(playername, category_id, entry_id)

Tells whether the specified entry is marked as “revealed” to the player and thus visible and generally accessible.

Parameters

• playername: Name of the player to check
• category_id: Category identifier of the category to check
• entry_id: Entry identifier of the entry to check

Return value

true, if entry is revealed, false otherwise.

doc.mark_entry_as_viewed(playername, category_id, entry_id)

Marks a particular entry as “viewed” (or read) by a player. This will also automatically reveal the entry to the player permanently.

Parameters

• playername: Name of the player for whom to mark an entry as “viewed”
• category_id: Category identifier of the category of the entry to mark
• entry_id: Entry identifier of the entry to mark

Returns

Always nil.

doc.mark_entry_as_revealed(playername, category_id, entry_id)

Marks a particular entry as “revealed” to a player. If the entry is declared as hidden, it will become visible in the list of entries for this player and will always be accessible with doc.show_entry. This change is permanently.

For entries which are not normally hidden, this function has no direct effect.

Parameters

• playername: Name of the player for whom to reveal the entry
• category_id: Category identifier of the category of the entry to reveal
• entry_id: Entry identifier of the entry to reveal

Returns

Always nil.

doc.add_entry_alias(category_id, entry_id, alias)

Adds a single alias for an entry. When an entry has an alias, supplying the alias to a function which demands an entry_id will work as if the original entry_id has been supplied. Aliases are true within one category only.

Parameters

• category_id: Category identifier of the category of the entry in question
• entry_id: The original (!) entry identifier of the entry to create an alias for
• alias: Alias (string) for entry_id

Return value

Always nil.

doc.add_entry_aliases(category_id, entry_id, aliases)

Adds an arbitrary amount of aliases for an entry at once. Apart from that, this function has the same effect as doc.add_entry_alias.

Parameters

• category_id: Category identifier of the category of the entry in question
• entry_id: The original (!) entry identifier of the entry to create aliases for
• aliases: Table/list of aliases (strings) for entry_id

Return value

Always nil.

doc.get_category_count()

Returns the number of registered categories.

doc.get_entry_count(category_id)

Returns the number of entries in a category.

Parameters

• category_id: Category identifier of the category in which to count entries

Return value

Number of entries in the specified category.

function doc.get_viewed_count(playername, category_id)

Returns how many entries have been viewed by a player.

Parameters

• playername: Name of the player to count the viewed entries for
• category_id: Category identifier of the category in which to count the viewed entries

Return value

Amount of entries the player has viewed in the specified category. If the player does not exist, this function returns nil.

function doc.get_revealed_count(playername, category_id)

Returns how many entries the player has access to (non-hidden entries) in this category.

Parameters

• playername: Name of the player to count the revealed entries for
• category_id: Category identifier of the category in which to count the revealed entries

Return value

Amount of entries the player has access to in the specified category. If the player does not exist, this function returns nil.

function doc.get_hidden_count(playername, category_id)

Returns how many entries are hidden from the player in this category.

Parameters

• playername: Name of the player to count the hidden entries for
• category_id: Category identifier of the category in which to count the hidden entries

Return value

Amount of entries hidden from the player. If the player does not exist, this function returns nil.

Extending this mod (naming conventions)

If you want to extend this mod with your own functionality, it is recommended that you put all API functions into doc.sub.<name>. As a naming convention, if your mod depends on doc, your mod name should also start with “doc_”, like doc_items, doc_minetest_game, doc_identifier.

One mod which uses this convention is doc_items which uses the doc.sub.items table.