Top-level toolkit artifacts

Two files contain toolkit metadata, the toolkit.xml file and the info.xml file. Both files are located under the toolkit root directory.

The toolkit.xml file serves as an index into the toolkit. A toolkit is considered as indexed only if its toolkit.xml file is up-to-date with the contents of the toolkit directory. Use only an indexed toolkit with a stream processing application. Creating toolkits gives the details on how the index is created using the spl-make-toolkit program. The info.xml file contains the name, description, and version information that is related to the toolkit. It is authored by the toolkit developer and is optional (see Creating toolkits for the defaults). It also contains any dependencies that the toolkit might have on other toolkits. It is recommended that the info.xml file is provided for a toolkit. Several optional directories might be present at the top level of the toolkit. The name and common usage are given in Table 1. These directories, and any subdirectories underneath them, are skipped during toolkit indexing. Directories with a leading period ('.') in the name (and their subtrees) are also skipped.

Structure the impl directory as the top-level toolkit directory, such as impl/lib, impl/include, impl/bin, and impl/nl.