twine.conf

Twine configuration file

Description

twine.conf is the configuration file used by components of Twine, a Linked Open Data workflow engine. The file uses the Windows .INI file format (albeit with Unix line-endings), with sets of configuration values split into groups. Each key and value pair begins on a new line within a section, with an equals sign separating the value from the key. Comments begin with a semicolon or hash sign at the start of a line.

For example: 


; This is a comment
[section1]
string1=value1
bool1=yes
bool2=false
int-option=124

[section2]
# This is another comment
string2 = another value

multi-string = This is a \
multi-line string \
value.

Value types

Strings
Strings are written as-is following the equals sign. Leading spaces will be trimmed. Multi-line strings are written by placing a backslash immediately before the newline character.
Booleans
Boolean values express either true or false. True is expressed either a non-zero integer, the word true, or the word yes. Any other expression will evaluate to false.
Integers
Integer values are simply whole decimal numbers. There is, at present, no mechanism for expressing hexadecimal, octal, or binary values.

[amqp] section

The [amqp] section contains global defaults for communication with the AMQP 1.0 message broker.

uri (String)

Specifies the default URI to use for AMQP connections. The URI takes the following general form:

amqp://user:auth-info@host:port/queue-or-exchange

[sparql] section

The [sparql] section specifies SPARQL endpoints which are used by twine-writerd to update the quad-store.

update (String)
Specifies the HTTP or HTTPS URI of a SPARQL 1.1 Update protocol endpoint which can be used to update the quad-store.
data (String)
Specifies the HTTP or HTTPS URI of a SPARQL 1.1 Graph Store protocol endpoint which can be used to update the quad-store. This endpoint will receive PUT requests when graphs must be updated.

[writerd]

The [writerd] section specifies configuration values used only by twine-writerd.

amqp-uri (String)
If supplied, contains an AMQP URI which is used by twine-writerd to connect to the message broker's queue instead of the default specified in the [amqp] section. This may be useful where the message broker topology or configuration dictates that the writer daemon must connect to a different endpoint to receive messages than bridges should use to send them.
pidfile (String)
Specifies the full pathname of the PID file which will be written by twine-writerd when it detaches from the controlling terminal and begins running in the background. If this file already exists, it must be writeable by the user the writer daemon is running as; alternatively, the parent directory must be writeable by that user.
module (String)

Specifies the name of a processor module to load.

If the filename contains a /, it is assumed to be an absolute path, or a path relative to the current working directory of the daemon when it is first executed. Otherwise, it is assumed to be the name of a file within the Twine modules directory. (Typically /usr/lib/twine).

This configuration key may be repeated as many times as there are modules which should be loaded.

[inject] section

The [inject] section specifies configuration values used only by twine-inject.

amqp-uri (String)
If supplied, contains an AMQP URI which is used by twine-inject to connect to the message broker's exchange instead of the default specified in the [amqp] section.

[log] section

The [log] section specifies logging defaults for any Twine daemons (in particular, twine-writerd).

syslog (Boolean)
Whether to send log messages to the system log using syslog3. The default is true.
stderr (Boolean)
Whether to send log messages to standard error. The default is false.
level (String)

Specifies the minimum severity of messages to be logged. Messages lower than this severity will be discarded.

The following log levels are defined (from lowest to highest severity):

  1. debug
  2. info
  3. notice
  4. warning or warn
  5. error or err
  6. critical or crit
  7. alert
  8. emergency or emerg

The default value is notice.

facility (String)

Specifies the logging facility where logging via syslog is enabled. The following facilities are defined:

  • auth
  • priv
  • cron
  • daemon
  • ftp
  • kern
  • lpr
  • mail
  • news
  • security
  • syslog
  • remoteauth
  • uucp
  • user
  • local0...local7

Note that not all facilities are available on all systems. Only user and local0...local7 are defined by the Single UNIX Specification.

The default value is daemon if the facility is available, and user otherwise.

ident (String)

Specifies the source ident which precedes log messages. It is not recommended that this value be specified in the configuration file.

The default value is the base name of the process generating the log message (e.g., twine-writerd).

See also

twine-writerd, twine-inject.