textops Module

Andrei Pelinescu-Onciul

FhG FOKUS

Edited by

Andrei Pelinescu-Onciul


Table of Contents
1. User's Guide
1.1. Overview
1.1.1. Known Limitations
1.2. Dependencies
1.2.1. OpenSER Modules
1.2.2. External Libraries or Applications
1.3. Exported Functions
1.3.1. search(re)
1.3.2. search_append(re, txt)
1.3.3. replace(re, txt)
1.3.4. replace_all(re, txt)
1.3.5. subst('/re/repl/flags')
1.3.6. subst_uri('/re/repl/flags')
1.3.7. subst_user('/re/repl/flags')
1.3.8. append_to_reply(txt)
1.3.9. append_hf(hf)
1.3.10. append_urihf(prefix, suffix)
1.3.11. is_present_hf(hf_name)
1.3.12. append_time()
1.4. Known Limitations
2. Developer's Guide
3. Frequently Asked Questions
List of Examples
1-1. search usage
1-2. search_append usage
1-3. replace usage
1-4. replace_all usage
1-5. subst usage
1-6. subst_uri usage
1-7. subst usage
1-8. append_to_reply usage
1-9. append_hf usage
1-10. append_urihf usage
1-11. is_present_hf usage
1-12. append_time usage

Chapter 1. User's Guide

1.1. Overview

This is mostly an example module. It implements text based operation (search, replace, append a.s.o).


1.1.1. Known Limitations

search ignores folded lines. For example, search("(From|f):.*@foo.bar") doesn't match the following From header field:

From: medabeda 
 <sip:medameda@foo.bar>;tag=1234

1.2. Dependencies

1.2.1. OpenSER Modules

The following modules must be loaded before this module:

  • No dependencies on other OpenSER modules.


1.2.2. External Libraries or Applications

The following libraries or applications must be installed before running OpenSER with this module loaded:

  • None.


1.3. Exported Functions

1.3.1. search(re)

Searches for the re in the message.

Meaning of the parameters is as follows:

  • re - Regular expression.

Example 1-1. search usage

...
if ( search("[Ss][Ee][Rr]" ) { /*....*/ };
...

1.3.2. search_append(re, txt)

Searches for the first match of re and appends txt after it.

Meaning of the parameters is as follows:

  • re - Regular expression.

  • txt - String to be appended.

Example 1-2. search_append usage

...
search_append("[Ss]er", " blabla");
...

1.3.3. replace(re, txt)

Replaces the first occurrence of re with txt.

Meaning of the parameters is as follows:

  • re - Regular expression.

  • txt - String.

Example 1-3. replace usage

...
replace("ser", "Sip Express Router");
...

1.3.4. replace_all(re, txt)

Replaces all occurrence of re with txt.

Meaning of the parameters is as follows:

  • re - Regular expression.

  • txt - String.

Example 1-4. replace_all usage

...
replace_all("ser", "Sip Express Router");
...

1.3.5. subst('/re/repl/flags')

Replaces re with repl (sed or perl like).

Meaning of the parameters is as follows:

  • '/re/repl/flags' - sed like regular expression. flags can be a combination of i (case insensitive), g (global) or s (match newline don't treat it as end of line).

Example 1-5. subst usage

...
# replace the uri in to: with the message uri (just an example)
if ( subst('/^To:(.*)sip:[^@]*@[a-zA-Z0-9.]+(.*)$/t:\1\u\2/ig') ) {};
...

1.3.6. subst_uri('/re/repl/flags')

Runs the re substitution on the message uri (like subst but works only on the uri)

Meaning of the parameters is as follows:

  • '/re/repl/flags' - sed like regular expression. flags can be a combination of i (case insensitive), g (global) or s (match newline don't treat it as end of line).

Example 1-6. subst_uri usage

...
# adds 3463 prefix to numeric uris, and save the original uri (\0 match)
# as a parameter: orig_uri (just an example)
if (subst_uri('/^sip:([0-9]+)@(.*)$/sip:3463\1@\2;orig_uri=\0/i')){$

...

1.3.7. subst_user('/re/repl/flags')

Runs the re substitution on the message uri (like subst_uri but works only on the user portion of the uri)

Meaning of the parameters is as follows:

  • '/re/repl/flags' - sed like regular expression. flags can be a combination of i (case insensitive), g (global) or s (match newline don't treat it as end of line).

Example 1-7. subst usage

...
# adds 3463 prefix to uris ending with 3642 (just an example)
if (subst_user('/3642$/36423463/')){$

...

1.3.8. append_to_reply(txt)

Append txt to the reply.

Meaning of the parameters is as follows:

  • txt - String.

Example 1-8. append_to_reply usage

...
append_to_reply("Foo: bar\r\n");
...

1.3.9. append_hf(hf)

Appends txt after the last header field.

Meaning of the parameters is as follows:

  • hf - Header field to be appended.

Example 1-9. append_hf usage

...
append_hf("P-hint: VOICEMAIL\r\n");
...

1.3.10. append_urihf(prefix, suffix)

Append header field name with original Request-URI in middle.

Meaning of the parameters is as follows:

  • prefix - string (usually at least header field name).

  • suffix - string (usually at least line terminator).

Example 1-10. append_urihf usage

...
append_urihf("CC-Diversion: ", "\r\n");
...

1.3.11. is_present_hf(hf_name)

Return true if a header field is present in message.

Note

Takes header field names "as is" and doesn't distinguish compact names.

Meaning of the parameters is as follows:

  • hf_name - Header field name.

Example 1-11. is_present_hf usage

...
if (is_present_hf("From")) log(1, "From HF Present");
...

1.3.12. append_time()

Adds a time header to the message. Header format is: "Date: %a, %d %b %Y %H:%M:%S GMT", with the legend:

  • %a abbreviated week of day name (locale)

  • %d day of month as decimal number

  • %b abbreviated month name (locale)

  • %Y year with century

  • %H hour

  • %M minutes

  • %S seconds

Return true if a header was succesfully appended

Example 1-12. append_time usage

...
append_time();
...

1.4. Known Limitations

Search functions are applied to the original request, i.e., they ignore all changes resulting from message processing in OPENSER script.


Chapter 2. Developer's Guide

The module does not provide any API to use in other OpenSER modules.


Chapter 3. Frequently Asked Questions

3.1. Where can I find more about OpenSER?
3.2. Where can I post a question about this module?
3.3. How can I report a bug?

3.1. Where can I find more about OpenSER?

Take a look at http://openser.org/.

3.2. Where can I post a question about this module?

First at all check if your question was already answered on one of our mailing lists:

E-mails regarding any stable OpenSER release should be sent to and e-mails regarding development versions should be sent to .

If you want to keep the mail private, send it to .

3.3. How can I report a bug?

Please follow the guidelines provided at: http://openser.org/bugs.