ToXmlDoc (Record function)

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Return in an XmlDoc the fields and values of the Record object's record (Record class)

[Requires Janus SOAP]

ToXmlDoc has options to display in uppercase or lowercase, as well as to output the values of a record's fields as XML attributes or as XML text of the field XML element.

The record extraction performed by ToXmlDoc is the same operation that is performed by the XmlDoc API methods LoadFromRecord and NewFromRecord, as is further described below in "Usage notes".

ToXmlDoc is available in Sirius Mods version 7.3 and later.

Syntax

%doc = record:ToXmlDoc[( [AttributeValues= boolean], - [AttributeNames= boolean], [NamesToLower= boolean], - [AllowUnreversible= boolean], - [CodepageTable= boolean], [Base64Encode= boolean], - [CharacterMap= characterToUnicodeMap], - [AllowNull= boolean])] Throws CharacterTranslationException

Syntax terms

%doc An XmlDoc object variable to contain the record data.
record An instantiated Record object variable.
AttributeValues This name required argument is a Boolean value that indicates whether a field value will be displayed as XML text or as an XML attribute (belonging to its field, which is displayed as an XmlDoc element).

For example, <APSUBUND>COMM</APSUBUND> is text format, and <APSUBUND value="COMM"/> is attribute value format.

The default value is False, which produces text format.
AttributeNames This name required argument is a Boolean value that indicates whether field names are to be displayed within their XML document elements as the element name or as the value of a "name" attribute.

For example, <APSUBUND>COMM</APSUBUND> is element-name format, and the following is name-as-attribute format:

<field name="APSUBUND"> COMM </field>

The default value as of Sirius Mods version 7.6 (and maintenance back to version 7.3) is True, which produces name-as-attribute format. Formerly, the default value was False. The name-as-attribute format from the True option is better suited to operations on the XmlDoc, particularly a record copying operation. The element-name format from the False option is useful for displaying field names that are not valid as XML element names (for example, names with embedded spaces).

For more information about handling non-valid XML names, see "Usage Notes," below.
NamesToLower This name required argument is a Boolean value that indicates whether field name data is to be displayed in lowercase characters. The default value is False, which produces uppercase output.
AllowUnreversible This name required argument is a Boolean value that indicates whether a request is cancelled if a field name would be changed irreversibly by lowercasing or by replacing with a period the characters that would be invalid in an XML document.

For example, as described below in "Usage Notes," fields FOO BAR and FOO%BAR would both produce the element name FOO.BAR if AttributeNames is set to False. This will cause request cancellation unless AllowUnreversible is set to True.

The default value is False, which allows request cancellation to alert you about unreversible field names.
CodepageTable This name required argument is a Boolean value; if True, the translations defined by the base Unicode codepage are used when translating from EBCDIC to Unicode for storing in the XmlDoc.

This argument is for the unusual case where you anticipate that the XML document is to be used later by AddToRecord, and the standard Unicode translation tables in place when AddToRecord is invoked may differ from those in place when the record was copied to the XmlDoc.

The default value is False, which uses the standard Unicode translation tables, including any modifications specified in UNICODE Trans or UNICODE Map commands. The advantage of using CodepageTable=False is that it will allow you to readily modify the XmlDoc directly (that is, with the AddElement and AddAttribute methods). Those operations will use the standard Unicode translation tables; there is no way to perform them using the base codepage translation tables.

CodepageTable is available as of Sirius Mods version 7.6.

AllowNull The value of this name required Boolean argument, which defaults to False, is copied to the AllowNull property of the XmlDoc created by ToXmlDoc. The XmlDoc's AllowNull property, in turn, determines whether field values that contain the X'00' character are stored in the XmlDoc with base64 encoding. Such values are base64 encoded if the AllowNull property is False (the default). For an example, see "Handling records with null characters" in the NewFromRecord method description.

AllowNull is available as of Sirius Mods version 7.7.

Usage notes

  • Whether to use ToXmlDoc, NewFromRecord, or LoadFromRecord depends on what is most convenient for your application. If you are already using a Record object which references the desired record, using ToXmlDoc may be more convenient; if not, then either LoadFromRecord or NewFromRecord (both of which require that the method be contained in a record loop, for example, For Each Record) may be more convenient. You must use LoadFromRecord if you want to add the record's content as a subtree to a non-empty XmlDoc; in other cases the NewFromRecord virtual constructor may be your choice.

    Since NewFromRecord and ToXmlDoc create new XmlDoc objects, they have the AllowNull argument for setting the created XmlDoc's AllowNull poperty; LoadFromRecord does not have the AllowNull argument.

    As stated, both NewFromRecord and LoadFromRecord must be contained in a record loop, for example, an FRN block, and they may not be invoked within a fieldgroup context.

    Except for these considerations, ToXmlDoc, NewFromRecord, and LoadFromRecord all perform the same operation and have the same arguments.

  • If any fields have name characters that are not valid when displayed as an XML element name, or if they have characters that are non-displayable when the name is formatted as an attribute value, the ToXmlDoc method converts the problematic characters to periods.

    For example, if field FOO BAR has value XXX, the AttributeNames parameter value is False, and the NamesToLower and AttributeValues parameters are set to True, the resulting display would be:

    <foo.bar value="XXX">

  • If NamesToLower is set to True, any field name containing lowercase characters is considered unreversible; reversing would involve converting the names to uppercase. To avoid request cancellation because of this, you must set to True the AllowUnreversible parameter.
  • In versions of Model 204 prior to 7.5, the effect of the Base64Encoding=False argument can be accomplished by post-processing the XmlDoc and replacing values which have an encoding="base64" attribute with the base 64 decoded value translated to Unicode.
  • UTF8 and UTF16 fields are copied directly to the XmlDoc; there is no translation (either automatic or using the CharacterMap argument) nor base 64 encoding involved for them.
  • If the Base64Encode argument is False (the default), and a non-UTF8/16 field value contains certain characters, the ToXmlDoc output data is automatically base64 encoded, and an attribute called encoding is added to the field's XML element with a value of base64. The cases that result in base64 encoding are:
    • The null character (X'00'), unless the XmlDoc has AllowNull=True
    • Any other non-displayable character, that is, the X'01' .. X'3F' control characters
    • A character that is not translatable to Unicode
    • A character e that translates to some Unicode character u, but the Unicode character u does not translate to e

    To exemplify these cases, consider this request based on some cleverly constructed records (although it uses LoadFromRecord, the output XmlDoc would be the same using ToXmlDoc):

    * Uses X'AD' as EBCDIC left square bracket (U+005B): UNICODE table standard base codepage 1047 * Not a good idea, but for this example, also use X'BA' as left square bracket: UNICODE table standard trans e=ba to u=005b b %doc is object xmlDoc for 5 records printText {~=$curRec} {~=(FOO):stringToHex} %doc = new %doc:loadFromRecord %doc:print skip 1 line end for frn 0 print '** Finally try null character again, this time with XmlDoc AllowNull=True: **' printText {~=$curRec} {~=(FOO):stringToHex} %doc = new %doc:allowNull = true %doc:loadFromRecord %doc:print end for end

    The output (again, with the records setup for this example) of the above request is:

    $curRec=0 (FOO):stringToHex=00 <Record version="1" file="QAWORK" number="0"> <field name="COMMENT"> Null character causes base64, unless AllowNull=True </field> <field name="FOO" encoding="base64"> AA== </field> </Record> $curRec=1 (FOO):stringToHex=01 <Record version="1" file="QAWORK" number="1"> <field name="COMMENT"> Control character causes base64 </field> <field name="FOO" encoding="base64"> AQ== </field> </Record> $curRec=2 (FOO):stringToHex=FF <Record version="1" file="QAWORK" number="2"> <field name="COMMENT"> Untranslatable character causes base64 </field> <field name="FOO" encoding="base64"> /w== </field> </Record> $curRec=3 (FOO):stringToHex=BA <Record version="1" file="QAWORK" number="3"> <field name="COMMENT"> Uninvertible translation causes base64 </field> <field name="FOO" encoding="base64"> ug== </field> </Record> $curRec=4 (FOO):stringToHex=AD <Record version="1" file="QAWORK" number="4"> <field name="COMMENT"> Invertible translation does *not* cause base64 </field> <field name="FOO"> [ </field> </Record> ** Finally try null character again, this time with XmlDoc AllowNull=True: ** $curRec=0 (FOO):stringToHex=00 <Record version="1" file="QAWORK" number="0"> <field name="COMMENT"> Null character causes base64, unless AllowNull=True </field> <field name="FOO"> &#x0; </field> </Record>

  • The ToXmlDoc method will copy all fields, except those the user does not have access to due to field level security. Note that the AddToRecord method, which allows you to copy a record extracted by ToXmlDoc into another record, may not add all of the copied fields.
  • The ToXmlDoc method will add BLOB values to the output XmlDoc, no matter how large they are. A BLOB field will have a reserved attribute added to the field element if more bytes were reserved in the BLOB than are in the actual value.
  • Typically, before they proceed, PAI, AppendFieldValues, and other operations that extract field names and values automatically get a share lock on a record if it appears to be unlocked. The ToXmlDoc method insists that the Record object be locked at least in share mode, therefore it gets no locks while it operates. No locks are required for a sorted record or in single-user mode. See "Getting record lock" below for an example of obtaining a share record lock when processing an unlocked found set.

Examples

In addition to the example in the following section, see the "Handling records with null characters" example in the NewFromRecord article, which applies equally to ToXmlDoc.

AttributeValues, AttributeNames, and NamesToLower arguments

The display of field data below is produced by the following request:

OPENC FILE CCASYS b %r is object record in file ccasys %r = new(1) %r:toXmlDoc:print %r:toXmlDoc(namesToLower=true):print %r:toXmlDoc(attributeValues=true):print %r:toXmlDoc(attributeValues=true, attributeNames=false, - namestoLower=true):print end

The following are sample results:

<Record file="CCASYS" number="1"> <field name="APSURTYP"> SDEF </field> <field name="APSUNM"> SUBSYSMGMT </field> <field name="APSUBUND"> COMM </field> <field name="APSUERRC"> ERROR </field> ... <Record file="CCASYS" number="1"> <field name="apsurtyp"> SDEF </field> <field name="apsunm"> SUBSYSMGMT </field> <field name="apsubund"> COMM </field> <field name="apsuerrc"> ERROR </field> ... <Record file="CCASYS" number="1"> <field name="APSURTYP" value="SDEF"/> <field name="APSUNM" value="SUBSYSMGMT"/> <field name="APSUBUND" value="COMM"/> <field name="APSUERRC" value="ERROR"/> ... <Record file="CCASYS" number="1"> <apsurtyp value="SDEF"/> <apsunm value="SUBSYSMGMT"/> <apsubund value="COMM"/> <apsuerrc value="ERROR"/> ...

Getting record lock

As stated in the "Usage notes" above, a record lock of at least Share strength is required for the record processed by ToXmlDoc. If you are processing an unlocked record set, you can use the LoopLockStrength property so that for each iteration of a For Each Record loop using the recordset, the current record is locked, as shown in the following example:

%recSet is object recordset in QAWORK * In this fragment, %rec is null, only used to qualify the currentRecord constructor %rec is object record in QAWORK find without locks all records to %recSet end find %recSet:loopLockStrength = share for each record in %recset ... %doc = %rec:currentRecord:toXmlDoc ... end for

Since the LoadFromRecord and NewFromRecord methods do not have a Record method object, using them in the above loop would be either %doc:loadFromRecord or %doc = newFromRecord, respectively (and in this fragment the %rec variable would not be needed).

See also

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