Daffodil provides tunables as a way to change its behavior.
Tunables are set by way of the tunables element in config files
or from the cli via the -T option.
<daf:dfdlConfig
xmlns:daf="urn:ogf:dfdl:2013:imp:daffodil.apache.org:2018:ext">
<daf:tunables>
<daf:suppressSchemaDefinitionWarnings>
encodingErrorPolicyError
</daf:suppressSchemaDefinitionWarnings>
</daf:tunables>
</daf:dfdlConfig>
The config file can then be passed into daffodil subcommands via the -c|--config options.
daffodil parse -s schema.xsd -TsuppressSchemaDefinitionWarnings="encodingErrorPolicyError" data.bin
Defines how Daffodil coerces expressions where the result type differs from the expected type. As an example, assume the expected type of an expression is an xs:string, but the expression is { 3 }. In this case, the expression result is an xs:int, which should not be automatically coerced to an xs:string. Instead, the expression should be { xs:string(3) } or { "3" } If the value of this tunable is false, these types of expressions will result in a schema definition error. If the value is true, Daffodil will provide a warning and attempt to coerce the result type to the expected type.
default: true
By default, path expressions in Daffodil will only work correctly if path steps are used in an expression defined in the schema when compiled. To enable the use of other expressions (e.g. during debugging, where not all expressions are known at schema compile time), set this tunable to true. This may cause a degredation of performance in path expression evaluation, so this should be avoided when in production. This flag is automatically enabled when debugging is enabled.
default: false
When processing signed binary integers, which should have a length of at least 2 bits, issue a warning if the length is less than 2 bits by default, otherwise (if false) issue a SDE or Processing Error.
default: true
When reading/writing blob data, the maximum number of bytes to read/write at a time. This is also used when parsing xs:hexBinary data.
default: 4096
Defines the default empty element parse policy to use if it is not defined in a schema. This is only used if requireEmptyElementParsePolicyProperty is false.
default: treatAsEmpty
This tunable allows the escalation of Schema Definition Warnings to Errors.
default: false
Stem to use when generating a namespace prefix when one is not defined for the target naespace.
default: tns
Initial array buffer size allocated for recurring elements/arrays.
default: 10
Initial number of characters to match when performing regular expression matches on input data. When a regex fails to match, more data may be consumed up to the maximumRegexMatchLengthInCharacters tunable.
default: 64
Daffodil periodically walks the internal infoset to send events to the configured InfosetOutputter, skipping at least this number of walk attempts. Larger values mean delayed InfosetOutputter events and more memory usage; Smaller values mean more CPU usage. Set this value to zero to never skip any walk attempts. This is specifically for advanced testing behavior and should not need to be changed by users.
default: 32
Daffodil periodically walks the internal infoset to send events to the configured InfosetOutputter. On walks where no progress is made, the number of walks to skip is increased with the assumption that something is blocking it (like an unresolved point of uncertainty), up to this maximum value. Higher values mean less attempts are made when blocked for a long time, but with potentially more delays and memory usage before InfosetOutputter events are created. This is specifically for advanced testing behavior and should not need to be changed by users.
default: 2048
DFDL only allows a subset of restrictions that XML Schema defines. For example, DFDL disallows the use of the xs:pattern restriction on simple types other than xs:string. This tunable configures this behavior to allow use of some of these restrictions. The allowed values are:
default: error
The largest allowed value of the dfdl:binaryDecimalVirtualPoint property.
default: 200
When unparsing, this is the maximum size of the buffer that the ByteArrayOutputStream can grow to before switching to a file based output stream.
default: 2097152000
The maximum size of data to retrive when when getting data to display for debugging.
default: 256
The maximum size allowed for an xs:hexBinary element.
default: 1073741823
When unexpected text is found where a delimiter is expected, this is the maximum number of bytes (characters) to display when the expected delimiter is a variable length delimiter.
default: 10
Max distance that the DPath lookahead function is permitted to look. Distance is defined by the distance to the last bit accessed, and so it is offset+bitsize.
default: 512
Maximum number of occurances of an array element.
default: 2147483647
Maximum number of bytes allowed to skip in a skip region.
default: 1024
Due to differences in the DFDL spec and ICU4J SimpleDateFormat, we must have SimpleDateFormat parse in lenient mode, which allows the year value to overflow with very large years into possibly negative years. This tunable tunable sets an upper limit for values to prevent overflow.
default: 9999
Maximum number of characters to match when performing regular expression matches on input data.
default: 1048576
Maximum number of characters to parse when parsing string data.
default: 1048576
The smallest allowed value of the dfdl:binaryDecimalVirtualPoint property.
default: -200
Due to differences in the DFDL spec and ICU4J SimpleDateFormat, we must have SimpleDateFormat parse in lenient mode, which allows the year value to overflow with very large years into possibly negative years. This tunable tunable sets an upper limit for values to prevent underflow.
default: 0
When writing file data to the output stream during unparse, this is the maximum number of bytes to write at a time.
default: 65536
Whether to compile a schema to support only parsing, only unparsing, both, or to use the daf:parseUnparsePolicy from the root node. All child elements of the root must have a compatable daf:parseUnaprsePolicy property.
default: fromRoot
Daffodil will periodically release internal infoset elements that it determines are no longer needed, thus freeing memory. Setting this value to false will prevent this from taking place. This should usually only be used while debugging or with very specific tests.
default: true
If true, require that the dfdl:bitOrder property is specified. If false, use a default value if the property is not defined in the schema.
default: false
If true, require that the dfdl:emptyElementParsePolicy property is specified in the schema. If false, and not defined in the schema, uses the defaultEmptyElementParsePolicy as the value of emptyElementParsePolicy.
default: false
If true, require that the dfdl:encodingErrorPolicy property is specified. If false, use a default value if the property is not defined in the schema.
default: false
If true, require that the dfdl:floating property is specified. If false, use a default value if the property is not defined in the schema.
default: false
If true, require that the dfdl:testBidi property is specified. If false, use a default value if the property is not defined in the schema.
default: false
If true, require that the dfdl:textStandardBase property is specified. If false and the property is missing, behave as if the property is set to 10.
default: false
Daffodil's SAX Unparse API allows events to be batched in memory to minimize the frequency of context switching between the SAXInfosetInputter thread that processes the events, and the DaffodilUnparseContentHandler thread that generates the events. Setting this value to a low number will increase the frequency of context switching, but will reduce the memory footprint. Swtting it to a high number will decrease the frequency of context switching, but increase the memory footprint.
default: 100
Space-separated list of schema definition warnings that should be ignored, or "all" to ignore all warnings.
default: emptyElementParsePolicyError
When unparsing, use this path to store temporary files that may be genrated. The default value (empty string) will result in the use of the java.io.tmpdir property being used as the path.
default: This string is ignored. Default value is taken from java.io.tmpdir property
Defines how to lookup DFDL expression path steps that to not include a namespace prefix. Values are:
default: noNamespace
While unparsing, some unparse actions require "suspending" which requires buffering unparse output until the suspension can be evaluated. Daffodil periodically attempts to reevaluate these suspensions so that these buffers can be released. We attempt to evaluate young suspensions shortly after creation with the hope that it will succeed and we can release associated buffers. But if a young suspension fails it is moved to the old suspension list. Old suspensions are evaluated less frequently since they are less likely to succeeded. This minimizes the overhead related to evaluating suspensions that are likely to fail. The unparseSuspensionWaitYoung and unparseSuspensionWaitOld values determine how many elements are unparsed before evaluating young and old suspensions, respectively.
default: 100
See unparseSuspensionWaitOld
default: 5