--- schema_version: "1" id: 3afc509175bc5ed2fc9759c20bfa40acffddfa1a612a7851ff3756c0d3345102 title: Flat File Format collection: mulesoft version: current locale: en-us portal_url: https://docs.salesforce.com/mulesoft/current/en-us/dataweave/2.3/dataweave-formats-flatfile.md canonical_url: https://docs.mulesoft.com/dataweave/2.3/dataweave-formats-flatfile source_site: docs.mulesoft.com content_type: documentation content_hash: 4726a419d5db96819400982e6dd85a729eab4a3409269e674eae588509ec51ad description: MuleSoft Documentation Site release: "2.3" latest: false --- --- product: DataWeave version: 2.3 --- # Flat File Format > For the full documentation index, see: https://docs.mulesoft.com/llms.txt MIME Type: `application/flatfile` ID: `flatfile` The Flat File format supports multiple types of fixed width records within a single message. The schema structure allows you to define how different record types are distinguished, and how the records are logically grouped. > [!NOTE] Flat File in DataWeave supports files of up to 15 MB, and the memory requirement is > roughly 40 to 1. For example, a 1-MB file requires up to 40 MB of memory to process, so it’s > important to consider this memory requirement in conjunction with your TPS needs for large flat > files. This is not an exact figure; the value might vary according to the complexity of the > mapping instructions. ## Example: Specify a Flat File Schema This example shows a DataWeave script that outputs data in the Flat File format. Notice that it uses the `schemaPath` and `structureIndent` writer properties. ```dataweave %dw 2.0 output application/flatfile schemaPath="src/main/resources/test-data/QBReqRsp.esl", structureIdent="QBResponse" --- payload ``` ## Configuration Properties DataWeave supports the following configuration properties for this format. ### Reader Properties DataWeave accepts properties that provide instructions for reading input data in this format.

Parameter	Type	Default	Description
`allowLenientWithBinaryNotEndElement`	`Boolean`	`false`	When the schema contains elements of type Binary or Packed, the `lenient` option does not allow short records, regardless of the last element’s format type. When you set this property to `true`, the validation applies only to cases in which the record ends with type Binary or Packed.
`enforceRequires`	`Boolean`	`false`	Error if required value missing. Valid values are `true` or `false`.
`missingValues`	`String`	`nulls` for copybook schema, `spaces` otherwise	Fill character used to represent missing values. To activate a non-default setting, set the `useMissCharAsDefaultForFill` property to `true`, and use one of the following values to `missingValues`: `none`: Treat all data as actual values `spaces`: Interpret a field consisting of only spaces as a missing value `zeroes`: Interpret numeric fields consisting of only '0' characters and character fields consisting of only spaces as missing values `nulls`: Interpret a field consisting only of 0 bytes as a missing value
`notTruncateDependingOnSubjectNotPresent`	`Boolean`	`false`	Fills the entire group when the DEPENDING ON subject is not present. Introduced in DataWeave 2.3 with the August 2021 release of Mule 4.3.0-20210622.
`recordParsing`	`String`	`strict`	Expected separation between lines/records: `strict`: Line break expected at exact end of each record. `lenient`: Line break is used, but records can be shorter or longer than the schema specifies. Do not use `lenient` if your payload lacks line breaks. The other options to `recordParsing` support records that lack line breaks. `noTerminator`: Records follow one another with no separation. This option is preferred for fixed-length records that lack a line break. `singleRecord`: Entire input is a single record. Note that schemas with type `Binary` or `Packed` don’t allow for line break detection, so setting `recordParsing` to `lenient` only allows long records to be handled, not short ones. These schemas also currently only work with certain single-byte character encodings (so not with UTF-8 or any multibyte format).
`schemaPath` (Required)	`String`	`null`	Schema definition. Location in your local disk of the schema file used to parse your input.
`segmentIdent`	`String`	`null`	Segment identifier in the schema for fixed width or copybook schemas (only needed when parsing a single segment/record definition and if the schema includes multiple segment definitions).
`structureIdent`	`String`	`null`	Structure identifier in schema for flatfile schemas (only needed when parsing a structure definition, and if the schema includes multiple structure definitions)
`truncateDependingOn`	`Boolean`	`false`	Truncate COBOL copybook DEPENDING ON values to the length used. Valid values are `true` or `false`.
`useMissCharAsDefaultForFill`	`Boolean`	`false`	By default, the flat file reader and writer use spaces for missing characters and ignore the setting of the `missingValues` property. When you set this property to `true`, the reader honors the setting of the `missingValues` property. Introduced in DataWeave 2.3 (2.3.0-20210823) for the September 2021 release of Mule 4.3.0-20210823. Valid values are `true` or `false`.
`zonedDecimalStrict`	`Boolean`	`false`	Use the `strict` ASCII form of sign encoding for COBOL copybook zoned decimal values. Valid values are `true` or `false`.

### Writer Properties DataWeave accepts properties that provide instructions for writing output data in this format.

Parameter	Type	Default	Description
`bufferSize`	`Number`	`8192`	Size of the buffer writer.
`deferred`	`Boolean`	`false`	When set to `true`, DataWeave generates the output as a data stream, and the script’s execution is deferred until it is consumed. Valid values are `true` or `false`.
`encoding`	`String`	`null`	Encoding to be used by this writer, such as `UTF-8`.
`enforceRequires`	`Boolean`	`false`	Error if a required value is missing. Valid values are `true` or `false`.
`missingValues`	`String`	`NULLS` for copybook schema, `SPACES` otherwise	Fill character used to represent missing values. To activate a non-default setting, use `useMissCharAsDefaultForFill`, and use one of the following values to `missingValues`: `NONE`: Write nothing for missing values. `SPACES`: Fill the field with spaces. `ZEROES`: Fill numeric fields with `0` characters and character fields with space characters. `NULLS`: Fill the field with 0 bytes.
`notTruncateDependingOnSubjectNotPresent`	`Boolean`	`false`	Fills the entire group when the DEPENDING ON subject is not present. Introduced in DataWeave 2.3 with the August 2021 release of Mule 4.3.0-20210622.
`recordTerminator`	`String`	System property `line.separator`	Record separator line break. Valid values: `lf` `cr` `crlf` `none` Note that in Mule versions 4.0.4 and later, this is only used as a separator when there are multiple records. Values translate directly to character codes (`none` leaves no termination on each record).
`retainEmptyStringFieldsOnParsing`	`Boolean`	`false`	When set to `true`, this property makes the reader retain fields that lack values and set their values to an empty string. Introduced in the January 2023 version of DataWeave 2.3 for Mule version 4.3.0-20221212.
`schemaPath` (Required)	`String`	`null`	Schema definition. Path where the schema file to be used is located.
`segmentIdent`	`String`	`null`	Segment identifier in the schema for fixed width or copybook schemas (only needed when writing a single segment/record definition, and if the schema includes multiple segment definitions).
`structureIdent`	`String`	`null`	Structure identifier in schema for flatfile schemas (only needed when writing a structure definition and if the schema includes multiple structure definitions).
`trimValues`	`Boolean`	`false`	Trim string values that are longer than the field width by truncating trailing characters. Valid values are `true` or `false`.
`truncateDependingOn`	`Boolean`	`false`	Truncate COBOL copybook DEPENDING ON values to the length used. Valid values are `true` or `false`.
`useMissCharAsDefaultForFill`	`Boolean`	`false`	By default, the flat file reader and writer use spaces for missing characters and ignore the setting of the `missingValues` property. When you set this property to `true`, the writer honors the setting of the `missingValues` property. Introduced in DataWeave 2.3 (2.3.0-20210823) for the September 2021 release of Mule 4.3.0-20210823.
`zonedDecimalStrict`	`Boolean`	`false`	Use the `strict` ASCII form of sign encoding for COBOL copybook zoned decimal values. Valid values are `true` or `false`.

## Supported MIME Types The Flat File format supports the following MIME types.

MIME Type
`*/flatfile`