Fallback Parser Stage

Fallback parser stage

The Fallback parser stage is useful for processing data that Fusion does not have a specified parsing process for. Fallback does not technically parse data, since it does not know what to do with it, it simply copies the raw bytes into a Solr document. If your Fusion parser stage configuration encounters data it does not know how to parse, such as someone’s proprietary data file format, it will copy it as-is, whereas if it encounters recognizable data in more common file types, such as PDFs, Fusion will parse the text and metadata using Tika.

The Fallback parser acts as the final stage that attempts to parse any documents that haven’t been parsed already. When the correct parsing stage lands on the data, it executes accordingly.

When entering configuration values in the UI, use unescaped characters, such as \t for the tab character. When entering configuration values in the API, use escaped characters, such as \\t for the tab character.

Fallback stage-specific properties

Property Description, Type

Enable this Parser Stage

type: boolean

default value: 'true'


Error Handling

type: string

default value: 'mark'

enum: { ignore log fail mark }


Parser ID

type: string

default value: 'dbeb15f1-9620-4ab7-804e-f90c6594c9a6'


use default media types for this Parser Stage

Indicates if parser stage should use the default media types. Unchecking this box means that ONLY the manually configured media types will be parsed by the parser and you then MUST provide at least one media type.

type: boolean

default value: 'true'


Maximum bytes to keep

type: integer

default value: '1048576'


Media Types for this Parser Stage

type: array of string


Only parse metadata

type: boolean

default value: 'false'


Prefix parsed fields with

Fields extracted by this parser will be prefixed with this string. The remainder of the field name will be as detected in the stream

type: string

maxLength: 20

pattern: ^$|^[A-Za-z_][A-Za-z0-9_\-\.]+$


File names to parse

Specify a file name or pattern that must be matched for this parser stage to run. Forward slashes ("/") are used to join names of files inside archives with the archive name.

type: array of object

object attributes: {
  pattern : {
    display name: File name or pattern
    type: string
    description : e.g.: "z.txt" or "*.md" or "/a/*/b/f.txt" for glob; "z.txt$" or ".*\.txt$" or "^/a/[^\/]*/b/f.txt$" for regex
  syntax : {
    display name: Pattern type
    type: string
    default value: 'glob'
    description : glob uses bash shell-style wildcards; regex uses Java (PCRE-style) regex
    enum: { glob regex     }



type: string

default value: 'fallback'

enum: { fallback }