Activity - fileWritingActivity

Activity Type: File

Description

The use of this activity requires the jar: "jakarta-oro-2.0.8.jar" to be loaded on the server, for the handling of regular expressions.

Edit the contents of a file:

Insert content.
Append content.
Delete content.
Replace content.

Examples

<!-- Insert "!!" at the first character position of the file -->
<fileWritingActivity name="insert">
  <file>path/file.ext</file>
  <locate>
    <offset>1</offset>
  </locate>
  <insert text="!!"/>
  <output name="out"/>
</fileWritingActivity>

<!-- Insert "!!" at the beginning of the file -->
<fileWritingActivity name="insert">
  <file>path/file.ext</file>
  <locate>
    <offset>start</offset>
    <perLine>true</perLine>
  </locate>
  <insert text="!!" />
  <output name="out"/>
</fileWritingActivity>

<!-- Append "!!" to the end of the file -->
<fileWritingActivity name="append">
  <file>path/file.ext</file>
  <append text="!!"/>
  <output name="out"/>
</fileWritingActivity>

<!-- Append "!!" to the end of each line -->
<fileWritingActivity name="append">
  <file>path/file.ext</file>
  <locate>
    <perLine>true</perLine>
  </locate>
  <append text="!!"/>
  <output name="out"/>
</fileWritingActivity>

<!-- Delete characters 1 to 4 inclusive from the file -->
<fileWritingActivity name="delete">
  <file>path/file.ext</file>
  <locate>
    <offset>1</offset>
    <length>3</length>
  </locate>
  <delete/>
  <output name="out"/>
</fileWritingActivity>

<!-- Delete the first three occurrences of the string "zonk" -->
<fileWritingActivity name="delete">
  <file>path/file.ext</file>
  <locate>
    <regexp>zonk</regexp>
    <match>1-3</match>
  </locate>
  <delete/>
  <output name="out"/>
</fileWritingActivity>

<!-- Replace the first, fourth, ninth, sixteenth occurrences -->
<!-- of the string "zonk"                                    -->
<fileWritingActivity name="matchSequence">
  <file>path/file.ext</file>
  <locate>
    <regexp>zonk</regexp>
    <match>1:4:9:...</match>
    <perLine>false</perLine>
  </locate>
  <replace text="!!" />
  <output name="out"/>
</fileWritingActivity>

<!-- Replace the third to final characters of the file with -->
<!-- input from the "data" activity output stream.          -->
<fileWritingActivity name="replaceOffsetPerLine">
  <file>path/file.ext</file>
  <locate>
    <offset>3</offset>
    <length>toEnd</length>
    <perLine>false</perLine>
  </locate>
  <replace from="data"/>
  <output name="out"/>
</fileWritingActivity>

Specification

Element fileWritingActivity:

Attribute name - unique name for the activity within the scope of a request.
Element file (required) - contains the path to the file to access. This path should be relative to the top-level directory exposed by the associated OGSA-DAI service and must not attempt to traverse up the directory hierarchy higher than this directory.
Element locate (zero or one) - contains an expression selecting part of the file, either a regular expression or a character span:
- A regular expression:
  - Element regexp (required) - contains a regular expression.
  - Element match (zero or one) - which instances of text matching the regular expression are to be used. A comma-separated list of values. Each value can be any of:
    - Positive integer e.g. 3
    - Range of positive integers e.g. 2-7
    - Infinite range of positive integers e.g. 3-
    - Strictly increasing infinite sequences of positive integers e.g. 1:4:9:...
  - Element perLine (zero or one) - specify that the action to be taken on the selection is to be performed per-line (true) or per-file (false).
- A character span:
  - Element offset (zero or one) - the start of the selected text area. Contains one of:
    - An integer representing a character position within the file.
    - end for the end of the file. Note that if the value of perLine is true then these actually mean the end of the line.
    - start for the start of the file.
  - Element length (zero or one) - number of characters from the offset to be selected. Contains one of:
    - An integer specifying the number of characters from the offset to be selected.
    - toEnd indicating that all characters from the offset to the end of the file are to be selected.
  - Element perLine (zero or one) - specify that the action to be taken on the selection is to be performed per-line (true) or per-file (false).
One of the following four elements (required):
- Element insert - insert text after the selected text.
  - One of the following two attributes:
    - Attribute text - text to insert.
    - Attribute from - name of an input stream providing the text to insert.
  - Attribute optimiseTime - optimise time (true) or memory (false) use.
- Element append - append text to the end of the file or line.
  - For this option no locate element need be provided.
  - One of the following two attributes:
    - Attribute text - text to append.
    - Attribute from - name of an input stream providing the text to append.
  - Attribute optimiseTime - optimise time (true) or memory (false) use.
- Element delete - delete the selected text.
  - Attribute optimiseTime - optimise time (true) or memory (false) use.
- Element replace - replace the selected text.
  - One of the following two attributes:
    - Attribute text - text to replace the selected text.
    - Attribute from - name of an input stream providing the text to replace the selected text.
  - Attribute optimiseTime - optimise time (true) or memory (false) use.
Element output (required) - a dummy output which receives the value 1 after the action is complete.

Input and Output Types

Input: replace from:
- java.lang.String
- byte[] - these are converted to a java.lang.String
- org.w3c.dom.Node - these are parsed into a java.lang.String
- Any other objects are converted to a java.lang.String via java.lang.Object.toString()
Output: output - java.lang.String

Warning to Service Deployers

This activity can be used by clients to potentially access any directory on your server below that exposed by the associated OGSA-DAI service.

Data Resource Accessor

This activity requires a data resource accessor that implements the following interface: uk.org.ogsadai.dataresource.FileAccessProvider