Class ::xo::db::Class

::xo::db::Class[i] create ... \
           [ -abstract_p (default "f") ] \
           [ -auto_save (default "false") ] \
           [ -id_column id_column ] \
           [ -name_method (default "") ] \
           [ -object_type (default "[self]") ] \
           [ -pretty_name pretty_name ] \
           [ -pretty_plural pretty_plural ] \
           [ -security_inherit_p (default "t") ] \
           [ -sql_package_name sql_package_name ] \
           [ -supertype (default "acs_object") ] \
           [ -table_name table_name ] \
           [ -with_table (default "true") ]

Defined in

Class Relations

  • class: ::xotcl::Class[i]
  • superclass: ::xotcl::Class[i]
  • subclass: ::xo::db::CrClass[i], ::xo::PackageMgr[i]
::xotcl::Class create ::xo::db::Class \
     -superclass ::xotcl::Class

Methods (to be applied on the object)

  • class_to_object_type (scripted)

     xo::db::Class[i] class_to_object_type

    Testcases:
    xotcl_core_tutorial_2, xotcl-core
    if {[:isclass $name]} {
      if {[$name exists object_type]} {
        # The specified class has an object_type defined; return it
        return [$name object_type]
      }
      if {![$name istype ::xo::db::Object]} {
        # The specified class is not subclass of ::xo::db::Object.
        # return acs_object in your desperation.
        return acs_object
      }
    }
    # Standard mapping rules
    switch -glob -- $name {
      ::xo::db::Object   {return acs_object}
      ::xo::db::CrItem   {return content_revision}
      ::xo::db::image    {return image}
      ::xo::db::CrFolder {return content_folder}
      ::xo::db::*        {return [string range $name 10 end]}
      default            {return $name}
    }
  • delete (scripted, public)

     xo::db::Class[i] delete -id id 

    Delete the object from the database

    Switches:
    -id (required)

    Testcases:
    xotcl_core_tutorial_2
    ::acs::dc call acs_object delete -object_id $id
  • delete_all_acs_objects (scripted, public)

     xo::db::Class[i] delete_all_acs_objects -object_type object_type 

    Delete all acs_objects of the object_type from the database.

    Switches:
    -object_type (required)

    Testcases:
    No testcase defined.
    set table_name [::xo::db::Class get_table_name -object_type $object_type]
    if {$table_name ne ""} {
      ::xo::dc dml delete_instances {delete from :table_name}
    }
  • drop_type (scripted, public)

     xo::db::Class[i] drop_type -object_type object_type  \
        [ -drop_table drop_table ] [ -cascade_p cascade_p ]

    Drop the object_type from the database and drop optionally the table. This method deletes as well all acs_objects of the object_type from the database.

    Switches:
    -object_type (required)
    -drop_table (optional, defaults to "f")
    -cascade_p (optional, defaults to "t")

    Testcases:
    No testcase defined.
    set table_name [::xo::db::Class get_table_name -object_type $object_type]
    if {$table_name ne ""} {
      if {[catch {
        ::xo::dc dml delete_instances "delete from $table_name"
        if {$drop_table} {
          ::xo::dc dml drop_table "drop table $table_name"
        }
      } errorMsg]} {
        ns_log error "error during drop_type: $errorMsg"
      }
    }
    ::acs::dc call acs_object_type drop_type  -object_type $object_type -drop_children_p $cascade_p
    return ""
  • exists_in_db (scripted, public)

     xo::db::Class[i] exists_in_db -id id 

    Check, if an acs_object exists in the database.

    Switches:
    -id (required)
    Returns:
    0 or 1

    Testcases:
    xotcl_core_tutorial_1, xotcl_core_tutorial_2, xotcl_core_tutorial_4, test_xo_db_object, test_cr_items
    return [::xo::dc 0or1row -prepare integer select_object {
      select 1 from acs_objects where object_id = :id
    }]
  • get_class_from_db (scripted, public)

     xo::db::Class[i] get_class_from_db [ -object_type object_type ]

    Fetch an acs_object_type from the database and create an XOTcl class from this information.

    Switches:
    -object_type (optional)
    Returns:
    class name of the created XOTcl class

    Testcases:
    xotcl_core_tutorial_3
    # some table_names and id_columns in acs_object_types are unfortunately uppercase,
    # so we have to convert to lowercase here....
    ::xo::dc 1row fetch_class {
      select object_type, supertype, pretty_name, lower(id_column) as id_column, lower(table_name) as table_name
      from acs_object_types where object_type = :object_type
    }
    set classname [:object_type_to_class $object_type]
    if {![:isclass $classname]} {
      # the XOTcl class does not exist, we create it
      #:log "--db create class $classname superclass $supertype"
      ::xo::db::Class create $classname  -superclass [:object_type_to_class $supertype]  -object_type $object_type  -supertype $supertype  -pretty_name $pretty_name  -id_column $id_column  -table_name $table_name  -sql_package_name [namespace tail $classname]  -noinit
    } else {
      #:log "--db we have a class $classname"
    }
    set attributes [::xo::dc list_of_lists get_atts {
      select attribute_name, pretty_name, pretty_plural, datatype,
      default_value, min_n_values, max_n_values
      from acs_attributes where object_type = :object_type
    }]
    
    set slots ""
    foreach att_info $attributes {
      lassign $att_info attribute_name pretty_name pretty_plural datatype  default_value min_n_values max_n_values
    
      # ignore some erroneous definitions in the acs meta model
      if {[info exists :exclude_attribute($table_name,$attribute_name)]} {
        continue
      }
    
      set defined_att($attribute_name) 1
      set cmd [list ::xo::db::Attribute create $attribute_name  -pretty_name $pretty_name  -pretty_plural $pretty_plural  -datatype $datatype  -min_n_values $min_n_values  -max_n_values $max_n_values]
    
      if {$default_value ne ""} {
        # if the default_value is "", we assume, no default
        lappend cmd -default $default_value
      }
      append slots $cmd \n
    }
    ad_try {
      $classname slots $slots
    } on error {errorMsg} {
      error "Error during slots: $errorMsg"
    }
    
    $classname init
    return $classname
  • get_instance_from_db (scripted, public)

     xo::db::Class[i] get_instance_from_db -id id 

    Create an XOTcl object from an acs_object_id. This method determines the type and initializes the object from the information stored in the database. The XOTcl object is destroyed automatically on cleanup (end of a connection request).

    Switches:
    -id (required, integer)
    Returns:
    fully qualified object

    Testcases:
    xotcl_core_tutorial_1, xotcl_core_tutorial_2, test_xo_db_object
    set type  [:get_object_type -id $id]
    set class [::xo::db::Class object_type_to_class $type]
    if {![:isclass $class]} {
      error "no class $class defined"
    }
    set r [$class create ::$id]
    $r db_1row dbqd..get_instance [$class fetch_query $id]
    $r set object_id $id
    $r destroy_on_cleanup
    $r initialize_loaded_object
    return $r
  • get_object_type (scripted, public)

     xo::db::Class[i] get_object_type -id id 

    Return the object type for the give id.

    Switches:
    -id (required, integer)
    Returns:
    object_type, typically an XOTcl class

    Testcases:
    xotcl_core_tutorial_1, xotcl_core_tutorial_2
    xo::xotcl_object_type_cache eval -partition_key $id $id {
      ::xo::dc 1row get_class "select object_type from acs_objects where object_id=:id"
      return $object_type
    }
  • get_table_name (scripted, public)

     xo::db::Class[i] get_table_name -object_type object_type 

    Get the table_name of an object_type from the database. If the object_type does not exist, the return value is empty.

    Switches:
    -object_type (required)
    Returns:
    table_name

    Testcases:
    xotcl_core_tutorial_2
    return [::xo::dc get_value get_table_name {
      select lower(table_name) as table_name from acs_object_types where object_type = :object_type
    } ""]
  • object_type_exists_in_db (scripted, public)

     xo::db::Class[i] object_type_exists_in_db [ -object_type object_type ]

    Check, if an object_type exists in the database.

    Switches:
    -object_type (optional)
    Returns:
    0 or 1

    Testcases:
    xotcl_core_tutorial_2, xotcl_core_tutorial_4
    return [::xo::dc 0or1row check_type {
      select 1 from acs_object_types where object_type = :object_type
    }]
  • object_type_to_class (scripted)

     xo::db::Class[i] object_type_to_class

    Testcases:
    xotcl_core_tutorial_1, xotcl-core, xotcl_core_tutorial_2, test_xo_db_object, test_cr_items, xowiki_test_cases, link_tests, slot_interactions, path_resolve
    switch -glob -- $name {
      acs_object       {return ::xo::db::Object}
      content_revision -
      content_item     {return ::xo::db::CrItem}
      content_folder   {return ::xo::db::CrFolder}
      ::*              {return $name}
      default          {return ::xo::db::$name}
    }

Methods (to be applied on instances)

  • check_table_atts (scripted, public)

     <instance of xo::db::Class[i]> check_table_atts

    Check table_name and id_column and set meaningful defaults, if these attributes are not provided.

    Testcases:
    xotcl_core_tutorial_2, xotcl_core_tutorial_3, xotcl_core_tutorial_4
    :check_default_values
    set table_name_error_tail ""
    set id_column_error_tail ""
    
    if {![info exists :sql_package_name]} {
      set :sql_package_name [self]
      #:log "-- sql_package_name of [self] is '${:sql_package_name}'"
    }
    if {[string length ${:sql_package_name}] > 30} {
      error "SQL package_name '${:sql_package_name}' can be maximal 30 characters long! Please specify a shorter sql_package_name in the class definition."
    }
    if {${:sql_package_name} eq ""} {
      error "Cannot determine SQL package_name. Please specify it explicitly!"
    }
    
    if {![info exists :table_name]} {
      set tail [namespace tail [self]]
      regexp {^::([^:]+)::} [self] _ head
      :table_name [string tolower ${head}_$tail]
      #:log "-- table_name of [self] is '[:table_name]'"
      set table_name_error_tail ", or use different namespaces/class names"
    }
    
    if {![info exists :id_column]} {
      set :id_column [string tolower [namespace tail [self]]]_id
      set id_column_error_tail ", or use different class names"
      #:log "-- created id_column '[:id_column]'"
    }
    
    if {![regexp {^[[:alpha:]_][[:alnum:]_]*$} [:table_name]]} {
      error "Table name '[:table_name]' is unsafe in SQL:  Please specify a different table_name$table_name_error_tail."
    }
    
    if {[string length [:table_name]] > 30} {
      error "SQL table_name '[:table_name]' can be maximal 30 characters long! Please specify a shorter table_name in the class definition."
    }
    
    if {![regexp {^[[:alpha:]_][[:alnum:]_]*$} [:id_column]]} {
      error "Name for id_column '[:id_column]' is unsafe in SQL:  Please specify a different id_column$id_column_error_tail"
    }
  • create_object_type (scripted, public)

     <instance of xo::db::Class[i]> create_object_type

    Create an acs object_type for the current XOTcl class

    Testcases:
    xotcl_core_tutorial_2
    :check_default_values
    :check_table_atts
    
    # The default supertype is acs_object. If the supertype
    # was not changed (still acs_object), we map the superclass
    # to the object_type to obtain the ACS supertype.
    if {${:supertype} eq "acs_object"} {
      set :supertype [::xo::db::Class class_to_object_type [:info superclass]]
    }
    
    ::acs::dc call acs_object_type create_type  -object_type   ${:object_type}  -supertype     ${:supertype}  -pretty_name   ${:pretty_name}  -pretty_plural ${:pretty_plural}  -table_name    ${:table_name}  -id_column     ${:id_column}  -abstract_p    ${:abstract_p}  -name_method   ${:name_method}  -package_name  [:sql_package_name]
  • drop_object_type (scripted, public)

     <instance of xo::db::Class[i]> drop_object_type \
        [ -cascade cascade ]

    Drop an acs object_type; cascde true means that the attributes are dropped as well.

    Switches:
    -cascade (optional, defaults to "true")

    Testcases:
    No testcase defined.
    ::acs::dc call acs_object_type drop_type  -object_type ${:object_type}  -cascade_p [expr {$cascade ? "t" : "f"}]
  • get_instances_from_db (scripted, public)

     <instance of xo::db::Class[i]> get_instances_from_db \
        [ -select_attributes select_attributes ] \
        [ -from_clause from_clause ] [ -where_clause where_clause ] \
        [ -orderby orderby ] [ -page_size page_size ] \
        [ -page_number page_number ] [ -initialize initialize ]

    Returns a set (ordered composite) of the answer tuples of an 'instance_select_query' with the same attributes. Note that the returned objects might by partially instantiated.

    Switches:
    -select_attributes (optional)
    -from_clause (optional)
    -where_clause (optional)
    -orderby (optional)
    -page_size (optional, defaults to "20")
    -page_number (optional)
    -initialize (optional, defaults to "true")
    Returns:
    ordered composite

    Testcases:
    No testcase defined.
    set s [:instantiate_objects  -object_class [self]  -sql [:instance_select_query  -select_attributes $select_attributes  -from_clause $from_clause  -where_clause $where_clause  -orderby $orderby  -page_size $page_size  -page_number $page_number  ]  -initialize $initialize]
    return $s
  • instance_select_query (scripted, public)

     <instance of xo::db::Class[i]> instance_select_query \
        [ -select_attributes select_attributes ] [ -orderby orderby ] \
        [ -where_clause where_clause ] [ -from_clause from_clause ] \
        [ -count on|off ] [ -page_size page_size ] \
        [ -page_number page_number ]

    Returns the SQL-query to select ACS Objects of the object_type of the class.

    Switches:
    -select_attributes (optional)
    attributes for the SQL query to be retrieved. if no attributes are specified, all attributes are retrieved.
    -orderby (optional)
    for ordering the solution set
    -where_clause (optional)
    clause for restricting the answer set
    -from_clause (optional)
    -count (optional, boolean, defaults to "false")
    return the query for counting the solutions
    -page_size (optional, defaults to "20")
    -page_number (optional)
    Returns:
    SQL query

    Testcases:
    No testcase defined.
    set tables [list]
    set id_column [:id_column]
    
    if {$count} {
      set select_attributes "count(*)"
      set orderby ""         ;# no need to order when we count
      set page_number  ""    ;# no pagination when count is used
    }
    
    set all_attributes [expr {$select_attributes eq ""}]
    set join_expressions [list]
    foreach cl [list [self] {*}[:info heritage]] {
      #if {$cl eq "::xo::db::Object"} break
      if {$cl eq "::xotcl::Object"} break
      set tn [$cl table_name]
    
      if {$tn  ne ""} {
        lappend tables $tn
        if {$all_attributes} {
          foreach {slot_name slot} [$cl array get db_slot] {
            # avoid duplicate output names
            set name [$slot name]
            if {![info exists names($name)]} {
              lappend select_attributes [$slot attribute_reference $tn]
            }
            set names($name) 1
          }
        }
        if {$cl ne [self]} {
          lappend join_expressions "$tn.[$cl id_column] = [:table_name].$id_column"
        }
      }
    }
    
    if {$page_number ne ""} {
      set limit $page_size
      set offset [expr {$page_size*($page_number-1)}]
    } else {
      set limit ""
      set offset ""
    }
    set sql [::xo::dc select  -vars   [join $select_attributes ,]  -from  "[join $tables ,] $from_clause"  -where  [string trim "[join $join_expressions { and }] $where_clause"]  -orderby $orderby  -limit $limit -offset $offset]
    return $sql
  • instantiate_objects (scripted, public)

     <instance of xo::db::Class[i]> instantiate_objects [ -dbn dbn ] \
        [ -sql sql ] [ -full_statement_name full_statement_name ] \
        [ -as_ordered_composite on|off ] [ -object_class object_class ] \
        [ -named_objects on|off ] \
        [ -object_named_after object_named_after ] \
        [ -destroy_on_cleanup on|off ] [ -keep_existing_objects on|off ] \
        [ -ignore_missing_package_ids on|off ] [ -initialize initialize ]

    Retrieve multiple objects from the database using the given SQL query and create XOTcl objects from the tuples.

    Switches:
    -dbn (optional)
    -sql (optional)
    The SQL query to retrieve tuples. Note that if the SQL query only returns a restricted set of attributes, the objects will be only partially instantiated.
    -full_statement_name (optional)
    -as_ordered_composite (optional, boolean, defaults to "true")
    return an ordered composite object preserving the order. If the flag is false, one has to use "info instances" to access the resulted objects.
    -object_class (optional, defaults to "::xotcl::Object")
    specifies the XOTcl class, for which instances are created.
    -named_objects (optional, boolean, defaults to "false")
    If this flag is true, the value of the id_column is used for the name of the created objects (object will be named e.g. ::13738). Otherwise, objects are created with the XOTcl "new" method to avoid object name clashes.
    -object_named_after (optional)
    -destroy_on_cleanup (optional, boolean, defaults to "true")
    If this flag is true, the objects (and ordered composite) will be automatically destroyed on cleanup (typically after the request was processed).
    -keep_existing_objects (optional, boolean, defaults to "false")
    -ignore_missing_package_ids (optional, boolean, defaults to "false")
    -initialize (optional, defaults to "true")
    can be used to avoid full initialization, when a large series of objects is loaded. Per default, these objects are initialized via initialize_loaded_object, when the are of type ::xo::db::Object

    Testcases:
    xowiki_test_cases
    
    if {$object_class eq ""} {set object_class [self]}
    if {$sql eq ""} {set sql [:instance_select_query]}
    if {$as_ordered_composite} {
      set __result [::xo::OrderedComposite new]
      if {$destroy_on_cleanup} {$__result destroy_on_cleanup}
    } else {
      set __result [list]
    }
    if {$named_objects} {
      if {$object_named_after eq ""} {
        set object_named_after [:id_column]
      }
    }
    
    set sets [uplevel [list ::xo::dc sets -dbn $dbn dbqd..[self proc] $sql]]
    foreach selection $sets {
      if {$named_objects} {
        set object_name ::[ns_set get $selection $object_named_after]
        if {[nsf::is object $object_name]} {
          set o $object_name
          set new 0
        } else {
          set o [$object_class create $object_name]
          set new 1
        }
      } else {
        set new 0
        set o [$object_class new]
      }
      if {$as_ordered_composite} {
        $__result add $o
      } else {
        if {$destroy_on_cleanup} {
          $o destroy_on_cleanup
        }
        lappend __result $o
      }
    
      if {!$new && $keep_existing_objects} {
        #ns_log notice "+++ instantiate_objects keep existing object $o"
        continue
      }
      $o mset [ns_set array $selection]
      ns_set free $selection
    
      if {[$o exists object_type]} {
        #
        # Set the object type if it looks like managed from XOTcl.
        #
        set object_type [$o set object_type]
        if {[string match "::*" $object_type]} {
          $o class $object_type
        }
      }
      if {$initialize && [$o istype ::xo::db::Object]} {
        if {![$o exists package_id]} {
          if {[$o exists object_package_id]} {
            $o set package_id [$o set object_package_id]
          } elseif {!$ignore_missing_package_ids} {
            ns_log warning "[namespace tail [$o info class]] $o has no package_id and no object_package_id"
          }
        }
        ad_try {
          $o initialize_loaded_object
        } on error {errorMsg} {
          set context [lmap var {name item_id revision_id} {
            if {![$o exists $var]} continue
            set _ "$var [$o set $var]"
          }]
          ns_log error "$o initialize_loaded_object [join $context]"  "=> [lsort [$o info vars]] -> $errorMsg"
        }
      }
      #:log "--DB more = $continue [$o serialize]"
    }
    
    return $__result
  • new_persistent_object (scripted, public)

     <instance of xo::db::Class[i]> new_persistent_object \
        [ -package_id package_id ] [ -creation_user creation_user ] \
        [ -creation_ip creation_ip ] args [ args... ]

    Create a new instance of the given class, configure it with the given arguments and insert it into the database. The XOTcl object is destroyed automatically on cleanup (end of a connection request).

    Switches:
    -package_id (optional)
    -creation_user (optional)
    -creation_ip (optional)
    Parameters:
    args (required)
    Returns:
    fully qualified object

    Testcases:
    xotcl_core_tutorial_1, xotcl_core_tutorial_2
    :get_context package_id creation_user creation_ip
    ::xo::dc transaction {
      set id [:new_acs_object  -package_id $package_id  -creation_user $creation_user  -creation_ip $creation_ip  ""]
      #[self class] set during_fetch 1
      ad_try {
        :create ::$id {*}$args
      } on error {errorMsg} {
        ad_log error "create fails: $errorMsg"
      }
      #[self class] unset during_fetch
      :initialize_acs_object ::$id $id
      ::$id insert
    }
    ::$id destroy_on_cleanup
    return ::$id
  • object_types (scripted, public)

     <instance of xo::db::Class[i]> object_types \
        [ -subtypes_first on|off ]

    Return the type and subtypes of the class, on which the method is called. If subtypes_first is specified, the subtypes are returned first.

    Switches:
    -subtypes_first (optional, boolean, defaults to "false")
    Returns:
    list of object_types

    Testcases:
    xotcl_core_tutorial_2, xotcl_core_tutorial_4
    return [::xo::dc list get_object_types  [:object_types_query -subtypes_first $subtypes_first]]

Variables

::xo::db::Class set __default_metaclass ::xotcl::Class
::xo::db::Class set __default_superclass ::xotcl::Object
::xo::db::Class array set exclude_attribute {persons,bio 1 persons,bio_mime_type 1}