DRAFT
Overview
This document describes the OpenCDS Configuration for version 1.3.x and above.
What's new?
- Dedicated schemas for describing configuration metadata.
- Migration tool to migrate configuration schema from the previous version (1.2.x, 1.1.x, etc.) to the new version.
- REST interface for adding/updating and retrieving the configuration metadata
- including reloadability of File-based configuration.
- Backwards compatibility with ClassPath- and File-based configuration.
- NOT compatible with previous schemas; migration is required.
- New backend configuration scheme using BerkeleyDB (BDB-JE).
- This is the only method that is supported via REST.
Schemas
Backend
The OpenCDS backend is configured using one of three methods: Classpath, Filesystem and BDB. The choice of configuration strategy is made within the opencds.properties
file (see OpenCDS RunTime Installation Guide for details).
Classpath
This configuration option is most useful when initially evaluating OpenCDS. (As an aside, we also use this option for our continuous builds for functional testing purposes.)
When OpenCDS is configured using the Classpath-based configuration, it will look for the configuration files contained in a .jar file in the main .war file. The opencds.properties
file must contain the following lines to enable this configuration strategy:
knowledge-repository.type=CLASSPATH knowledge-repository.path=resources_v1.3
Filesystem
When OpenCDS is configured using the Filesystem-based configuration, it will look for the configuration files in a folder specified by the knowledge-repository-path
option in the opencds.properties
file. The opencds.properties file must contain the following lines to enable this configuration strategy:
knowledge-repository.type=SIMPLE_FILE knowledge-repository.path=<path_to_resources_v1.3>
Examples of "path_to_resources_v1.3" include:
- C:/opencds-knowledge-repository-data/resources_v1.3
- (Note the forward-slashes for Windows-based systems)
- /home/opencds/knowledge-repository-data/resources_v1.3
BerkeleyDB (BDB)
When OpenCDS is configured using the BDB-based configuration, it will look for configuration in the BDB database in the store
folder within the folder specified by the knowledge-repository-path
. The opencds.properties
file must contain the following lines to enable this configuration strategy:
knowledge-repository.type=STORE knowledge-repository.path=<path_to_store>
If the store
folder does not exist, OpenCDS will create it at startup. Please note, however, as this will be a new store, OpenCDS will contain no configuration at all; the Migration tool or the REST Client (see below for each) may be used to upload the configuration metadata to OpenCDS.
Additionally, the folder specified by knowledge-repository.path
will also contain two other folders (in addition to store
; also created by OpenCDS if they do not exist):
knowledgePackages
supportingData
These folders will contain the binary knowledge packages (e.g., from Guvnor), and any supporting data which will be used by OpenCDS (the implementation of which will be implemented at a later date) before passing the data into the inferencing engine. These files are not stored in BDB in order to keep the database size to a minimum.
Security
The backend configuration also requires a security file, which contains the username and passwords for each user and the roles for each...
REST API
Security
Methods
Configuration API (REST) Version 1.0
REST Client
Migration
A migration path has been provided in order to facilitate migration from configuration file formats from 1.2.x and previous versions.
The migration code supports two methods of migration from version 1.2.x and earlier, namely file-based and REST service-based.
Data must be in previous formats for migration to succeed.
File-based Migration
The file-based method reads from the files in a standard 1.2.x or earlier configuration, transforms the metadata, and writes them in their new format in the specified target location. Recall that prior to 1.3.x, OpenCDS required a specific layout for configuration files in addition to a directory/folder layout for the files. File-based configuration for version 1.3.x also requires a similar layout, but this is handled by the migration program.
<migration example here>
REST Service-based Migration
The REST Service-based migration reads from the files in a standard 1.2.x or earlier configuration, transforms the metadata, and uploads them to the OpenCDS service. The storage locations of these files are handled by OpenCDS; all files must be updated through the REST Configuration Service.
<migration example here>