libs/uvl/luasrc/uvl.lua

   1 --[[
   2
   3 UCI Validation Layer - Main Library
   4 (c) 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
   5 (c) 2008 Steven Barth <steven@midlink.org>
   6
   7 Licensed under the Apache License, Version 2.0 (the "License");
   8 you may not use this file except in compliance with the License.
   9 You may obtain a copy of the License at
  10
  11         http://www.apache.org/licenses/LICENSE-2.0
  12
  13 $Id$
  14
  15 ]]--
  16
  17 module( "luci.uvl", package.seeall )
  18
  19 require("luci.fs")
  20 require("luci.util")
  21 require("luci.model.uci")
  22 require("luci.uvl.datatypes")
  23 --require("luci.uvl.validation")
  24 require("luci.uvl.dependencies")
  25
  26 TYPE_SECTION  = 0x01
  27 TYPE_VARIABLE = 0x02
  28 TYPE_ENUM     = 0x03
  29
  30 STRICT_UNKNOWN_SECTIONS = true
  31 STRICT_UNKNOWN_OPTIONS  = true
  32
  33
  34 local default_schemedir = "/etc/scheme"
  35
  36 local function _assert( condition, fmt, ... )
  37         if not condition then
  38                 return assert( nil, string.format( fmt, ... ) )
  39         else
  40                 return condition
  41         end
  42 end
  43
  44 UVL = luci.util.class()
  45
  46 function UVL.__init__( self, schemedir )
  47         self.schemedir  = schemedir or default_schemedir
  48         self.packages   = { }
  49         self.beenthere  = { }
  50         self.uci                = luci.model.uci
  51         self.datatypes  = luci.uvl.datatypes
  52 end
  53
  54 function UVL._keys( self, tbl )
  55         local keys = { }
  56         if tbl then
  57                 for k, _ in luci.util.kspairs(tbl) do
  58                         table.insert( keys, k )
  59                 end
  60         end
  61         return keys
  62 end
  63
  64
  65 --- Validate given configuration.
  66 -- @param config        Name of the configuration to validate
  67 -- @param scheme        Scheme to validate against (optional)
  68 -- @return                      Boolean indicating weather the given config validates
  69 -- @return                      String containing the reason for errors (if any)
  70 function UVL.validate( self, config )
  71
  72         self.uci.set_confdir( self.uci.confdir_default )
  73         self.uci.load( config )
  74
  75         local co = self.uci.get_all( config )
  76
  77         local function _uci_foreach( type, func )
  78                 local ok, err
  79                 for k, v in pairs(co) do
  80                         if co[k]['.type'] == type then
  81                                 ok, err = func( k, v )
  82                                 if not ok then break end
  83                         end
  84                 end
  85                 return ok, err
  86         end
  87
  88         for k, v in pairs( self.packages[config].sections ) do
  89                 local ok, err = _uci_foreach( k,
  90                         function(s)
  91                                 local sect = luci.uvl.section( self, co, k, config, s )
  92                                 return self:_validate_section( sect )
  93                         end
  94                 )
  95                 if not ok then return false, err end
  96         end
  97
  98         if STRICT_UNKNOWN_SECTIONS then
  99                 for k, v in pairs(co) do
 100                         if not self.beenthere[config..'.'..k] then
 101                                 return false, "Section '" .. config .. '.' .. co[k]['.type'] ..
 102                                         "' not found in scheme"
 103                         end
 104                 end
 105         end
 106
 107         return true, nil
 108 end
 109
 110 function UVL.validate_section( self, config, section )
 111         self.uci.set_confdir( self.uci.confdir_default )
 112         self.uci.load( config )
 113
 114         local co = self.uci.get_all( config )
 115         if co[section] then
 116                 return self:_validate_section( luci.uvl.section(
 117                         self, co, co[section]['.type'], config, section
 118                 ) )
 119         else
 120                 return false, "Section '" .. config .. '.' .. section ..
 121                         "' not found in config. Nothing to do."
 122         end
 123 end
 124
 125 function UVL.validate_option( self, config, section, option )
 126         self.uci.set_confdir( self.uci.confdir_default )
 127         self.uci.load( config )
 128
 129         local co = self.uci.get_all( config )
 130         if co[section] and co[section][option] then
 131                 return self:_validate_option( luci.uvl.option(
 132                         self, co, co[section]['.type'], config, section, option
 133                 ) )
 134         else
 135                 return false, "Option '" ..
 136                         config .. '.' .. section .. '.' .. option ..
 137                         "' not found in config. Nothing to do."
 138         end
 139 end
 140
 141 --- Validate given section of given configuration.
 142 -- @param config        Name of the configuration to validate
 143 -- @param section       Key of the section to validate
 144 -- @param scheme        Scheme to validate against
 145 -- @return                      Boolean indicating weather the given config validates
 146 -- @return                      String containing the reason for errors (if any)
 147 function UVL._validate_section( self, section )
 148
 149         if section:values() then
 150
 151                 for _, v in ipairs(section:variables()) do
 152                         local ok, err = self:_validate_option( v )
 153
 154                         if not ok then
 155                                 return ok, err
 156                         end
 157                 end
 158
 159                 local ok, err = luci.uvl.dependencies.check( self, section )
 160
 161                 if not ok then
 162                         return false, "All possible dependencies failed"
 163                 end
 164         else
 165                 print( "Error, scheme section '" .. section:sid() .. "' not found in data" )
 166         end
 167
 168         if STRICT_UNKNOWN_OPTIONS and not section:section().dynamic then
 169                 for k, v in pairs(section:values()) do
 170                         if k:sub(1,1) ~= "." and not self.beenthere[
 171                                 section:cid() .. '.' .. k
 172                         ] then
 173                                 return false, "Option '" .. section:sid() .. '.' .. k ..
 174                                         "' not found in scheme"
 175                         end
 176                 end
 177         end
 178
 179         return true, nil
 180 end
 181
 182 --- Validate given option within section of given configuration.
 183 -- @param config        Name of the configuration to validate
 184 -- @param section       Key of the section to validate
 185 -- @param option        Name of the option to validate
 186 -- @param scheme        Scheme to validate against
 187 -- @return                      Boolean indicating weather the given config validates
 188 -- @return                      String containing the reason for errors (if any)
 189 function UVL._validate_option( self, option, nodeps )
 190
 191         if not option:option() and
 192            not ( option:section() and option:section().dynamic )
 193         then
 194                 return false, "Requested option '" .. option:sid() ..
 195                         "' not found in scheme"
 196         end
 197
 198         if option:option() then
 199                 if option:option().required and not option:value() then
 200                         return false, "Mandatory variable '" .. option:cid() ..
 201                                 "' doesn't have a value"
 202                 end
 203
 204                 if option:option().type == "enum" and option:value() then
 205                         if not option:option().values or
 206                            not option:option().values[option:value()]
 207                         then
 208                                 return false, "Value '" .. ( option:value() or '<nil>' ) ..
 209                                         "' of given option '" .. option:cid() ..
 210                                         "' is not defined in enum { " ..
 211                                         table.concat(self:_keys(option:option().values),", ") ..
 212                                         " }"
 213                         end
 214                 end
 215
 216                 if option:option().datatype and option:value() then
 217                         if self.datatypes[option:option().datatype] then
 218                                 if not self.datatypes[option:option().datatype](
 219                                         option:value()
 220                                 ) then
 221                                         return false, "Value '" .. ( option:value() or '<nil>' ) ..
 222                                                 "' of given option '" .. option:cid() ..
 223                                                 "' doesn't validate as datatype '" ..
 224                                                 option:option().datatype .. "'"
 225                                 end
 226                         else
 227                                 return false, "Unknown datatype '" ..
 228                                         option:option().datatype .. "' encountered"
 229                         end
 230                 end
 231
 232                 if not nodeps then
 233                         return luci.uvl.dependencies.check( self, option )
 234                 end
 235         end
 236
 237         return true, nil
 238 end
 239
 240 --- Find all parts of given scheme and construct validation tree
 241 -- @param scheme        Name of the scheme to parse
 242 -- @return                      Parsed scheme
 243 function UVL.read_scheme( self, scheme )
 244         local schemes = { }
 245
 246         for i, file in ipairs( luci.fs.glob(self.schemedir .. '/*/' .. scheme) ) do
 247                 _assert( luci.fs.access(file), "Can't access file '%s'", file )
 248
 249                 self.uci.set_confdir( luci.fs.dirname(file) )
 250                 self.uci.load( luci.fs.basename(file) )
 251
 252                 table.insert( schemes, self.uci.get_all( luci.fs.basename(file) ) )
 253         end
 254
 255         return self:_read_scheme_parts( scheme, schemes )
 256 end
 257
 258 -- Process all given parts and construct validation tree
 259 function UVL._read_scheme_parts( self, scheme, schemes )
 260
 261         -- helper function to construct identifiers for given elements
 262         local function _id( c, t )
 263                 if c == TYPE_SECTION then
 264                         return string.format(
 265                                 "section '%s.%s'",
 266                                         scheme, t.name or '?' )
 267                 elseif c == TYPE_VARIABLE then
 268                         return string.format(
 269                                 "variable '%s.%s.%s'",
 270                                         scheme, t.section or '?.?', t.name or '?' )
 271                 elseif c == TYPE_ENUM then
 272                         return string.format(
 273                                 "enum '%s.%s.%s'",
 274                                         scheme, t.variable or '?.?.?', t.value or '?' )
 275                 end
 276         end
 277
 278         -- helper function to check for required fields
 279         local function _req( c, t, r )
 280                 for i, v in ipairs(r) do
 281                         _assert( t[v], "Missing required field '%s' in %s", v, _id(c, t) )
 282                 end
 283         end
 284
 285         -- helper function to validate references
 286         local function _ref( c, t )
 287                 local k
 288                 if c == TYPE_SECTION then
 289                         k = "package"
 290                 elseif c == TYPE_VARIABLE then
 291                         k = "section"
 292                 elseif c == TYPE_ENUM then
 293                         k = "variable"
 294                 end
 295
 296                 local r = luci.util.split( t[k], "." )
 297                 r[1] = ( #r[1] > 0 and r[1] or scheme )
 298
 299                 _assert( #r == c, "Malformed %s reference in %s", k, _id(c, t) )
 300
 301                 return r
 302         end
 303
 304         -- Step 1: get all sections
 305         for i, conf in ipairs( schemes ) do
 306                 for k, v in pairs( conf ) do
 307                         if v['.type'] == 'section' then
 308
 309                                 _req( TYPE_SECTION, v, { "name", "package" } )
 310
 311                                 local r = _ref( TYPE_SECTION, v )
 312
 313                                 self.packages[r[1]] =
 314                                         self.packages[r[1]] or {
 315                                                 ["sections"]  = { };
 316                                                 ["variables"] = { };
 317                                         }
 318
 319                                 local p = self.packages[r[1]]
 320                                           p.sections[v.name]  = p.sections[v.name]  or { }
 321                                           p.variables[v.name] = p.variables[v.name] or { }
 322
 323                                 local s = p.sections[v.name]
 324
 325                                 for k, v2 in pairs(v) do
 326                                         if k ~= "name" and k ~= "package" and k:sub(1,1) ~= "." then
 327                                                 if k:match("^depends") then
 328                                                         s["depends"] = _assert(
 329                                                                 self:_read_dependency( v2, s["depends"] ),
 330                                                                 "Section '%s' in scheme '%s' has malformed " ..
 331                                                                 "dependency specification in '%s'",
 332                                                                 v.name or '<nil>', scheme or '<nil>', k
 333                                                         )
 334                                                 else
 335                                                         s[k] = v2
 336                                                 end
 337                                         end
 338                                 end
 339                         end
 340                 end
 341         end
 342
 343         -- Step 2: get all variables
 344         for i, conf in ipairs( schemes ) do
 345                 for k, v in pairs( conf ) do
 346                         if v['.type'] == "variable" then
 347
 348                                 _req( TYPE_VARIABLE, v, { "name", "section" } )
 349
 350                                 local r = _ref( TYPE_VARIABLE, v )
 351
 352                                 local p = _assert( self.packages[r[1]],
 353                                         "Variable '%s' in scheme '%s' references unknown package '%s'",
 354                                         v.name, scheme, r[1] )
 355
 356                                 local s = _assert( p.variables[r[2]],
 357                                         "Variable '%s' in scheme '%s' references unknown section '%s'",
 358                                         v.name, scheme, r[2] )
 359
 360                                 s[v.name] = s[v.name] or { }
 361
 362                                 local t = s[v.name]
 363
 364                                 for k, v in pairs(v) do
 365                                         if k ~= "name" and k ~= "section" and k:sub(1,1) ~= "." then
 366                                                 if k:match("^depends") then
 367                                                         t["depends"] = _assert(
 368                                                                 self:_read_dependency( v, t["depends"] ),
 369                                                                 "Variable '%s' in scheme '%s' has malformed " ..
 370                                                                 "dependency specification in '%s'",
 371                                                                 v.name, scheme, k
 372                                                         )
 373                                                 elseif k:match("^validator") then
 374                                                         t["validators"] = _assert(
 375                                                                 self:_read_validator( v, t["validators"] ),
 376                                                                 "Variable '%s' in scheme '%s' has malformed " ..
 377                                                                 "validator specification in '%s'",
 378                                                                 v.name, scheme, k
 379                                                         )
 380                                                 else
 381                                                         t[k] = v
 382                                                 end
 383                                         end
 384                                 end
 385                         end
 386                 end
 387         end
 388
 389         -- Step 3: get all enums
 390         for i, conf in ipairs( schemes ) do
 391                 for k, v in pairs( conf ) do
 392                         if v['.type'] == "enum" then
 393
 394                                 _req( TYPE_ENUM, v, { "value", "variable" } )
 395
 396                                 local r = _ref( TYPE_ENUM, v )
 397
 398                                 local p = _assert( self.packages[r[1]],
 399                                         "Enum '%s' in scheme '%s' references unknown package '%s'",
 400                                         v.value, scheme, r[1] )
 401
 402                                 local s = _assert( p.variables[r[2]],
 403                                         "Enum '%s' in scheme '%s' references unknown section '%s'",
 404                                         v.value, scheme, r[2] )
 405
 406                                 local t = _assert( s[r[3]],
 407                                         "Enum '%s' in scheme '%s', section '%s' references " ..
 408                                         "unknown variable '%s'",
 409                                         v.value, scheme, r[2], r[3] )
 410
 411                                 _assert( t.type == "enum",
 412                                         "Enum '%s' in scheme '%s', section '%s' references " ..
 413                                         "variable '%s' with non enum type '%s'",
 414                                         v.value, scheme, r[2], r[3], t.type )
 415
 416                                 if not t.values then
 417                                         t.values = { [v.value] = v.title or v.value }
 418                                 else
 419                                         t.values[v.value] = v.title or v.value
 420                                 end
 421
 422                                 if v.default then
 423                                         _assert( not t.default,
 424                                                 "Enum '%s' in scheme '%s', section '%s' redeclares " ..
 425                                                 "the default value of variable '%s'",
 426                                                 v.value, scheme, r[2], v.variable )
 427
 428                                         t.default = v.value
 429                                 end
 430                         end
 431                 end
 432         end
 433
 434         return self
 435 end
 436
 437 -- Read a dependency specification
 438 function UVL._read_dependency( self, value, deps )
 439         local parts     = luci.util.split( value, "%s*,%s*", nil, true )
 440         local condition = { }
 441
 442         for i, val in ipairs(parts) do
 443                 local k, v = unpack(luci.util.split( val, "%s*=%s*", nil, true ))
 444
 445                 if k and (
 446                         k:match("^%$?[a-zA-Z0-9_]+%.%$?[a-zA-Z0-9_]+%.%$?[a-zA-Z0-9_]+$") or
 447                         k:match("^%$?[a-zA-Z0-9_]+%.%$?[a-zA-Z0-9_]+$") or
 448                         k:match("^%$?[a-zA-Z0-9_]+$")
 449                 ) then
 450                         condition[k] = v or true
 451                 else
 452                         return nil
 453                 end
 454         end
 455
 456         if not deps then
 457                 deps = { condition }
 458         else
 459                 table.insert( deps, condition )
 460         end
 461
 462         return deps
 463 end
 464
 465 -- Read a validator specification
 466 function UVL._read_validator( self, value, validators )
 467         local validator
 468
 469         if value and value:match("/") and self.datatypes.file(value) then
 470                 validator = value
 471         else
 472                 validator = self:_resolve_function( value )
 473         end
 474
 475         if validator then
 476                 if not validators then
 477                         validators = { validator }
 478                 else
 479                         table.insert( validators, validator )
 480                 end
 481
 482                 return validators
 483         end
 484 end
 485
 486 -- Resolve given path
 487 function UVL._resolve_function( self, value )
 488         local path = luci.util.split(value, ".")
 489
 490         for i=1, #path-1 do
 491                 local stat, mod = pcall(require, table.concat(path, ".", 1, i))
 492                 if stat and mod then
 493                         for j=i+1, #path-1 do
 494                                 if not type(mod) == "table" then
 495                                         break
 496                                 end
 497                                 mod = mod[path[j]]
 498                                 if not mod then
 499                                         break
 500                                 end
 501                         end
 502                         mod = type(mod) == "table" and mod[path[#path]] or nil
 503                         if type(mod) == "function" then
 504                                 return mod
 505                         end
 506                 end
 507         end
 508 end
 509
 510
 511 section = luci.util.class()
 512
 513 function section.__init__(self, scheme, co, st, c, s)
 514         self.csection = co[s]
 515         self.ssection = scheme.packages[c].sections[st]
 516         self.cref     = { c, s }
 517         self.sref     = { c, st }
 518         self.scheme   = scheme
 519         self.config   = co
 520         self.type     = luci.uvl.TYPE_SECTION
 521 end
 522
 523 function section.cid(self)
 524         return ( self.cref[1] or '?' ) .. '.' .. ( self.cref[2] or '?' )
 525 end
 526
 527 function section.sid(self)
 528         return ( self.sref[1] or '?' ) .. '.' .. ( self.sref[2] or '?' )
 529 end
 530
 531 function section.values(self)
 532         return self.csection
 533 end
 534
 535 function section.section(self)
 536         return self.ssection
 537 end
 538
 539 function section.variables(self)
 540         local v = { }
 541         if self.scheme.packages[self.sref[1]].variables[self.sref[2]] then
 542                 for o, _ in pairs(
 543                         self.scheme.packages[self.sref[1]].variables[self.sref[2]]
 544                 ) do
 545                         table.insert( v, luci.uvl.option(
 546                                 self.scheme, self.config, self.sref[2],
 547                                 self.cref[1], self.cref[2], o
 548                         ) )
 549                 end
 550         end
 551         return v
 552 end
 553
 554
 555 option = luci.util.class()
 556
 557 function option.__init__(self, scheme, co, st, c, s, o)
 558         self.coption = co[s] and co[s][o] or nil
 559         self.soption = scheme.packages[c].variables[st][o]
 560         self.cref    = { c, s, o }
 561         self.sref    = { c, st, o }
 562         self.scheme  = scheme
 563         self.config  = co
 564         self.type    = luci.uvl.TYPE_OPTION
 565 end
 566
 567 function option.cid(self)
 568         return ( self.cref[1] or '?' ) .. '.' ..
 569                    ( self.cref[2] or '?' ) .. '.' ..
 570                    ( self.cref[3] or '?' )
 571 end
 572
 573 function option.sid(self)
 574         return ( self.sref[1] or '?' ) .. '.' ..
 575                    ( self.sref[2] or '?' ) .. '.' ..
 576                    ( self.sref[3] or '?' )
 577 end
 578
 579 function option.value(self)
 580         return self.coption
 581 end
 582
 583 function option.option(self)
 584         return self.soption
 585 end
 586
 587 function option.section(self)
 588         return self.scheme.packages[self.sref[1]].sections[self.sref[2]]
 589 end