docproc.proc

Processing content is mainly done by docproc.proc, with some minor exception for docproc.fileinput, which feeds file-based data into the processing queues being handled by docproc.proc.

When invoking docproc.proc, you may specify any of the following options:

docproc.proc [-hv] [-c file] [-l file]
-c <file>

Load the configuration from the passed file. If not provided, docproc.proc will try to read from the configuration file docproc-proc.conf in the current working directory.

-h

Print a short description of all command-line options and exit.

-l <file>

Log information to the passed file.

-v

Print version details and information about the build configuration and exit.

Configuration

The configuration file uses an INI-style layout.

Logging

Logging is configured via the [log] section. It can contain two entries.

file
The file to use for logging. This can be a file or writable socket. If omitted, STDERR will be used.
level
The log level to use. The log level uses the severity values of RFC-5424 in either numerical (0, 3, …) or textual form (Error, Info, …). If omitted, Error will be used.
[log]
file = /var/log/docproc-fileinput.log
level = Info

The [log] section is optional and, if omitted, logging will happen on STDERR with the log level Error.

Note

It is recommended to use the log level Error in a production environment to spot message processing issues (e.g. a queue being not reachable anymore). In rare situations, docproc.fileinput may use a more severe log level to indicate critical internal application problems.

In-, Output and Error Queue

The input queue to read messages from is configured via the [in-queue] section. The output queue to write processed messages for other consumers is configured via the [out-queue] section. If you want to preserve messages, that failed to process, you can also coonfigure an error queue via the [error-queue] section.

Configuration entries for the queue(s) may vary slightly, depending on the used message queue provider. The following entries are required nevertheless.

[in-queue]
type = nsq
host = 127.0.0.1:4161
topic = input

[out-queue]
type = nsq
host = 127.0.0.1:4150
topic = output

[error-queue]
type = nsq
host = 127.0.0.1:4150
topic = error
type

The message queue type to use. This can be one of

  • beanstalk
  • nats
  • nsq
host
The host or URI to use for connecting to the queue. The exact connection string to use varies, depending on the queue type and your service layout.
topic

[in-queue]: The message queue topic to read messages from for processing.

[out-queue]: The message queue topic to write to. Consumers, such as following docproc.proc instances can use the same topic to receive and process the incoming messages.

[error-queue]: The message queue topic to write failed messages to.

Processors

Processors are activated in the [execute] section and configured in an own, user-defined section. The [execute] section tells docproc.proc, which other sections it shall read to configure the appropriate handlers.

handlers
A comma-separated list of sections to use for configuring and activating processors. The entries must match a section within the configuration file. The processors are executed in the order of appearance.

Processing the message stops immediately, if one of the configured processors cannot sucessfully process the message. If an [error-queue] is configured, docproc.proc will write the message in its current state to that queue.

# Processors
[execute]
handlers = add-data, xml-transform

# Processor of type "ValueEnricher"
[add-data]
type = ValueEnricher
rules = /app/rules/preproc/testrules.json

# Processor of type TemplateTransformer"
[xml-transform]
type = TemplateTransformer
output = _xml_
templates = /app/templates/preproc/*.tpl
templateroot = main

The currently supported processors are explained in the chapter Processors.