Large configuration improvements, text helpers

Readme.md

@@ -8,4 +8,11 @@ No dependencies. Licensed under the MIT License. Written by Lars Mueller aka LMD
 
 ## API
 
-Mostly self-documenting code. Mod namespace is `modlib` or `_ml`, containing all variables & functions.
+Mostly self-documenting code. Mod namespace is `modlib` or `_ml`, containing all variables & functions.
+
+## Configuration
+
+1. Configuration is loaded from `<worldpath>/config/<modname>.<extension>`, the following extensions are supported and will be searched for (in that order):
+   1. [`json`](https://json.org)
+   2. [`conf`](https://github.com/minetest/minetest/blob/master/doc/lua_api.txt)
+2. Settings are loaded and override configuration values

conf.lua

@@ -2,13 +2,84 @@ minetest.mkdir(minetest.get_worldpath().."/config")
 function get_path(confname)
     return minetest.get_worldpath().."/config/"..confname
 end
-function load (filename, constraints)
+function read_conf(text)
+    local lines = modlib.text.split_lines(text, nil, true)
+    local dict = {}
+    for i, line in ipairs(lines) do
+        local error_base = "Line " .. (i+1) .. ": "
+        line = modlib.text.trim_left(lines[i])
+        if line ~= "" and line:sub(1,1) ~= "#" then
+            line = modlib.text.split(line, "=", 2)
+            if #line ~= 2 then
+                error(error_base .. "No value given")
+            end
+            local prop = modlib.text.trim_right(line[1])
+            if prop == "" then
+                error(error_base .. "No key given")
+            end
+            local val = modlib.text.trim_left(line[2])
+            if val == "" then
+                error(error_base .. "No value given")
+            end
+            if modlib.text.starts_with(val, '"""') then
+                val = val:sub(3)
+                local total_val = {}
+                local function readMultiline()
+                    while i < #lines do
+                        if modlib.text.ends_with(val, '"""') then
+                            val = val:sub(1, val:len() - 3)
+                            return
+                        end
+                        table.insert(total_val, val)
+                        i = i + 1
+                        val = lines[i]
+                    end
+                    i = i - 1
+                    error(error_base .. "Unclosed multiline block")
+                end
+                readMultiline()
+                table.insert(total_val, val)
+                val = table.concat(total_val, "\n")
+            else
+                val = modlib.text.trim_right(val)
+            end
+            if dict[prop] then
+                error(error_base .. "Duplicate key")
+            end
+            dict[prop] = val
+        end
+    end
+    return dict
+end
+function build_tree(dict)
+    local tree = {}
+    for key, value in pairs(dict) do
+        local path = modlib.text.split_unlimited(key, ".")
+        local subtree = tree
+        for i = 1, #path - 1 do
+            local index = tonumber(path[i]) or path[i]
+            subtree[index] = subtree[index] or {}
+            subtree = subtree[index]
+        end
+        subtree[path[#path]] = value
+    end
+    return tree
+end
+function build_setting_tree()
+    modlib.conf.settings = build_tree(minetest.settings:to_table())
+end
+function check_config_constraints(config, constraints, handler)
+    local no_error, error_or_retval = pcall(function() check_constraints(config, constraints) end)
+    if not no_error then
+        handler(error_or_retval)
+    end
+end
+function load(filename, constraints)
     local config = minetest.parse_json(modlib.file.read(filename))
     if constraints then
-        local error_message = check_constraints(config, constraints)
+        check_config_constraints(config, constraints, function(message)
-        if error_message then
+            error('Configuration of file "'..filename.."\" doesn't satisfy constraints: "..message)
-            error("Configuration - "..filename.." doesn't satisfy constraints: "..error_message)
+        end)
-        end
     end
     return config
 end
@@ -16,86 +87,191 @@ function load_or_create(filename, replacement_file, constraints)
     modlib.file.create_if_not_exists_from_file(filename, replacement_file)
     return load(filename, constraints)
 end
-function import(modname, constraints)
+function import(modname, constraints, no_settingtypes)
-    return load_or_create(get_path(modname)..".json", modlib.mod.get_resource(modname, "default_config.json"), constraints)
+    local default_config = modlib.mod.get_resource(modname, "default_config.json")
+    local config = load_or_create(get_path(modname)..".json", default_config, constraints)
+    if not no_settingtypes then
+        constraints.name = modname
+        local settingtypes = generate_settingtypes(minetest.parse_json(modlib.file.read(default_config)), constraints)
+        modlib.file.write(modlib.mod.get_resource(modname, "settingtypes.txt"), settingtypes)
+    end
+    local additional_settings = modlib.conf.settings[modname] or {}
+    additional_settings = fix_types(additional_settings, constraints)
+    config = merge_config(config, additional_settings)
+    if constraints then
+        check_config_constraints(config, constraints, function(message)
+            error('Configuration of mod "'..modname.."\" doesn't satisfy constraints: "..message)
+        end)
+    end
+    return config
 end
-function check_constraints(value, constraints)
+function merge_config(config, additional_settings)
-    local t=type(value)
+    if not config or type(additional_settings) ~= "table" then
-    if constraints.func then
+        return additional_settings
-        local possible_errors=constraints.func(value)
+    end
-        if possible_errors then
+    for setting, value in pairs(additional_settings) do
-            return possible_errors
+        if config[setting] then
+            config[setting] = merge_config(config[setting], value)
         end
     end
-    if constraints.type and constraints.type~=t then
+    return config
-        return "Wrong type: Expected "..constraints.type..", found "..t
+end
+-- format: # comment
+-- name (Readable name) type type_args
+function generate_settingtypes(default_conf, constraints)
+    local constraint_type = constraints.type
+    if constraints.children or constraints.possible_children or constraints.required_children or constraints.keys or constraints.values then
+        constraint_type = "table"
+    end
+    local settingtype, type_args
+    local title = constraints.title
+    if not title then
+        title = modlib.text.split(constraints.name, "_")
+        title[1] = modlib.text.upper_first(title[1])
+        title = table.concat(title, " ")
+    end
+    if constraint_type == "boolean" then
+        settingtype = "bool"
+        default_conf = default_conf and "true" or "false"
+    elseif constraint_type == "string" then
+        settingtype = "string"
+    elseif constraint_type == "number" then
+        settingtype = constraints.int and "int" or "float"
+        local range = constraints.range
+        if range then
+            -- TODO consider better max
+            type_args = (constraints.int and "%d %d" or "%f %f"):format(range[1], range[2] or math.pow(2, 30))
+        end
+    elseif constraint_type == "table" then
+        local handled = {}
+        local settings = {}
+        local function setting(key, value_constraints)
+            if handled[key] then
+                return
+            end
+            handled[key] = true
+            value_constraints.name = constraints.name .. "." .. key
+            value_constraints.title = title .. " " .. key
+            table.insert(settings, generate_settingtypes(default_conf and default_conf[key], value_constraints))
+        end
+        for _, table in ipairs{"children", "required_children", "possible_children"} do
+            for key, constraints in pairs(constraints[table] or {}) do
+                setting(key, constraints)
+            end
+        end
+        return table.concat(settings, "\n")
+    end
+    if not constraint_type then
+        return ""
+    end
+    local comment = constraints.comment
+    if comment then
+        comment = "# " .. comment .. "\n"
+    else
+        comment = ""
+    end
+    assert(type(default_conf) == "string" or type(default_conf) == "number" or type(default_conf) == "nil", dump(default_conf))
+    return comment .. constraints.name .. " (" .. title  .. ") " .. settingtype .. " " .. (default_conf or "") ..(type_args and (" "..type_args) or "")
+end
+function fix_types(value, constraints)
+    local type = type(value)
+    local expected_type = constraints.type
+    if expected_type and expected_type ~= type then
+        assert(type == "string", "Can't fix non-string value")
+        if expected_type == "boolean" then
+            assert(value == "true" or value == "false", "Not a boolean (true or false): " .. value)
+            value = value == "true"
+        elseif expected_type == "number" then
+            assert(tonumber(value), "Not a number: " .. value)
+            value = tonumber(value)
+        end
+    end
+    if type == "table" then
+        for key, val in pairs(value) do
+            for _, child_constraints in ipairs{"required_children", "children", "possible_children"} do
+                child_constraints = (constraints[child_constraints] or {})[key]
+                if child_constraints then
+                    val = fix_types(val, child_constraints)
+                end
+            end
+            if constraints.values then
+                val = fix_types(val, constraints.values)
+            end
+            if constraints.keys then
+                value[key] = nil
+                value[fix_types(key, constraints.keys)] = val
+            else
+                value[key] = val
+            end
+        end
+    end
+    return value
+end
+function check_constraints(value, constraints)
+    local t = type(value)
+    if constraints.type and constraints.type ~= t then
+        error("Wrong type: Expected "..constraints.type..", found "..t)
     end
     if (t == "number" or t == "string") and constraints.range then
         if value < constraints.range[1] or (constraints.range[2] and value > constraints.range[2]) then
-            return "Not inside range: Expected value >= "..constraints.range[1].." and <= "..constraints.range[1]..", found "..minetest.write_json(value)
+            error("Not inside range: Expected value >= "..constraints.range[1].." and <= "..(constraints.range[2] or "inf")..", found "..minetest.write_json(value))
         end
     end
+    if t == "number" and constraints.int and value % 1 ~= 0 then
+        error("Not an integer number: " .. minetest.write_json(value))
+    end
     if constraints.possible_values and not constraints.possible_values[value] then
-        return "None of the possible values: Expected one of "..minetest.write_json(modlib.table.keys(constraints.possible_values))..", found "..minetest.write_json(value)
+        error("None of the possible values: Expected one of "..minetest.write_json(modlib.table.keys(constraints.possible_values))..", found "..minetest.write_json(value))
     end
     if t == "table" then
         if constraints.children then
-            for k, v in pairs(value) do
+            for key, val in pairs(value) do
-                local child=constraints.children[k]
+                local child_constraints = constraints.children[key]
-                if not child then
+                if not child_constraints then
-                    return "Unexpected table entry: Expected one of "..minetest.write_json(modlib.table.keys(constraints.children))..", found "..minetest.write_json(k)
+                    error("Unexpected table entry: Expected one of "..minetest.write_json(modlib.table.keys(constraints.children))..", found "..minetest.write_json(key))
                 else
-                    local possible_errors=check_constraints(v, child)
+                    check_constraints(val, child_constraints)
-                    if possible_errors then
-                        return possible_errors
-                    end
                 end
             end
-            for k, _ in pairs(constraints.children) do
+            for key, _ in pairs(constraints.children) do
-                if value[k] == nil then
+                if value[key] == nil then
-                    return "Table entry missing: Expected key "..minetest.write_json(k).." to be present in table "..minetest.write_json(value)
+                    error("Table entry missing: Expected key "..minetest.write_json(key).." to be present in table "..minetest.write_json(value))
                 end
             end
         end
         if constraints.required_children then
-            for k,v_constraints in pairs(constraints.required_children) do
+            for key, value_constraints in pairs(constraints.required_children) do
-                local v=value[k]
+                local val = value[key]
-                if v then
+                if val then
-                    local possible_errors=check_constraints(v, v_constraints)
+                    check_constraints(val, value_constraints)
-                    if possible_errors then
-                        return possible_errors
-                    end
                 else
-                    return "Table entry missing: Expected key "..minetest.write_json(k).." to be present in table "..minetest.write_json(value)
+                    error("Table entry missing: Expected key "..minetest.write_json(key).." to be present in table "..minetest.write_json(value))
                 end
             end
         end
         if constraints.possible_children then
-            for k,v_constraints in pairs(constraints.possible_children) do
+            for key, value_constraints in pairs(constraints.possible_children) do
-                local v=value[k]
+                local val = value[key]
-                if v then
+                if val then
-                    local possible_errors=check_constraints(v, v_constraints)
+                    check_constraints(val, value_constraints)
-                    if possible_errors then
-                        return possible_errors
-                    end
                 end
             end
         end
         if constraints.keys then
-            for k,_ in pairs(value) do
+            for key,_ in pairs(value) do
-                local possible_errors=check_constraints(k, constraints.keys)
+                check_constraints(key, constraints.keys)
-                if possible_errors then
-                    return possible_errors
-                end
             end
         end
         if constraints.values then
-            for _,v in pairs(value) do
+            for _, val in pairs(value) do
-                local possible_errors=check_constraints(v, constraints.values)
+                check_constraints(val, constraints.values)
-                if possible_errors then
-                    return possible_errors
-                end
             end
         end
     end
+    if constraints.func then
+        local possible_errors = constraints.func(value)
+        if possible_errors then
+            error(possible_errors)
+        end
+    end
 end

init.lua

@@ -77,6 +77,8 @@ for component, additional in pairs(components) do
     end
 end
 
+modlib.conf.build_setting_tree()
+
 modlib.mod.loadfile_exports = loadfile_exports
 
 -- complete the string library (=metatable) with text helpers

mod.conf

@@ -1,2 +1,3 @@
 name=modlib
 description=Multipurpose Minetest Modding Library
+author=LMD aka appguru(eu)

text.lua

@@ -41,35 +41,58 @@ function trim_begin(str, to_remove)
     return str:sub(j)
 end
 
-function split(str, delim, limit)
+trim_left = trim_begin
-    if not limit then return split_without_limit(str, delim) end
+
+function trim_end(str, to_remove)
+    local k = 1
+    for i = string.len(str), 1, -1 do
+        if str:sub(i, i) ~= to_remove then
+            k = i
+            break
+        end
+    end
+    return str:sub(1, k)
+end
+
+trim_right = trim_end
+
+function split(str, delim, limit, regex)
+    if not limit then return split_without_limit(str, delim, regex) end
+    local no_regex = not regex
     local parts = {}
     local occurences = 1
     local last_index = 1
-    local index = string.find(str, delim, 1, true)
+    local index = string.find(str, delim, 1, no_regex)
     while index and occurences < limit do
         table.insert(parts, string.sub(str, last_index, index - 1))
         last_index = index + string.len(delim)
-        index = string.find(str, delim, index + string.len(delim), true)
+        index = string.find(str, delim, index + string.len(delim), no_regex)
         occurences = occurences + 1
     end
     table.insert(parts, string.sub(str, last_index))
     return parts
 end
 
-function split_without_limit(str, delim)
+function split_without_limit(str, delim, regex)
+    local no_regex = not regex
     local parts = {}
     local last_index = 1
-    local index = string.find(str, delim, 1, true)
+    local index = string.find(str, delim, 1, no_regex)
     while index do
         table.insert(parts, string.sub(str, last_index, index - 1))
         last_index = index + string.len(delim)
-        index = string.find(str, delim, index + string.len(delim), true)
+        index = string.find(str, delim, index + string.len(delim), no_regex)
     end
     table.insert(parts, string.sub(str, last_index))
     return parts
 end
 
+split_unlimited = split_without_limit
+
+function split_lines(str, limit)
+    modlib.text.split(str, "\r?\n", limit, true)
+end
+
 hashtag = string.byte("#")
 zero = string.byte("0")
 nine = string.byte("9")