FileAttributesFilter
Retrieves and exposes a record from a delimiter-separated file. Lookup of the
record is performed using a specified key, whose value is derived from an
expression. The resulting record is exposed in an object whose location is
specified by the target expression. If a matching record cannot be found,
then the resulting object is empty.
The retrieval of the record is performed lazily; it does not occur until the
first attempt to access a value in the target. This defers the overhead of
file operations and text processing until a value is first required. This also
means that the value expression is not evaluated until the object is first
accessed.
Usage
{
"name": string,
"type": "FileAttributesFilter",
"config": {
"file": configuration expression<string>,
"charset": configuration expression<string>,
"separator": configuration expression<enumeration>,
"header": configuration expression<boolean>,
"fields": [ configuration expression<string>, ... ],
"target": lvalue-expression,
"key": configuration expression<string>,
"value": runtime expression<string>
}
}For an example, refer to Password replay from a file.
Properties
"file": configuration expression<string>, required-
The file containing the record to be read.
"charset": configuration expression<string>, optional-
The character set in which the file is encoded.
Default:
"UTF-8". "separator": configuration expression<enumeration>, optional-
The separator character, which is one of the following:
COLON-
Unix-style colon-separated values, with backslash as the escape character.
COMMA-
Comma-separated values, with support for quoted literal strings.
TAB-
Tab-separated values, with support for quoted literal strings.
Default:
COMMA "header": configuration expression<boolean>,optional-
A flag to treat the first row of the file as a header row.
When the first row of the file is treated as a header row, the data in that row is disregarded and cannot be returned by a lookup operation.
Default:
true. "fields": array of configuration expression<strings>, optional-
A list of keys in the order they appear in a record.
If
fieldsis not set, the keys are assigned automatically by the column numbers of the file. "target": <lvalue-expression>, required-
Expression that yields the target object to contain the record.
The target object is a
Map<String, String>, where the fields are the keys. For example, if the target is${attributes.file}and the record has ausernamefield and apasswordfield mentioned in the fields list, Then you can access the user name as${attributes.file.username}and the password as${attributes.file.password}.See also Expressions.
"key": configuration expression<string>, required-
The key used for the lookup operation.
"value": runtime expression<string>, required-
The value to be looked-up in the file.
See also Expressions.