YANG2DSDL(1) pyang manual YANG2DSDL(1)NAMEyang2dsdl - translates YANG data models to DSDL schemas and validates
instance documents.
SYNOPSISyang2dsdl [-t target] [-d dir] [-b basename] [-j] [-v instance] file...
yang2dsdl-L [-t target] [-d dir] [-b basename] [-j] [-v instance] file
yang2dsdl-s [-t target] [-d dir] -b basename [-j] -v instance
yang2dsdl-h
DESCRIPTION
This shell script facilitates the translation of a data model described
by one or more input YANG modules to DSDL schemas (RELAX NG, Schematron
and DSRL) for a selected instance XML document type, as described in
RFC 6110[1]. Optionally, the script can validate an instance document
of the given type against the schemas.
The input YANG module(s) may be given either directly as file
parameter(s) on the command line, or indirectly through a server
<hello> message which also declares capabilities and features supported
by the server. The latter alternative is indicated by the -L switch,
and only one file parameter may be given in this case.
Input YANG module(s) may be expressed in YANG or YIN syntax. The output
DSDL schemas are written to the directory dir (current directory by
default). Unless the option -s is used, this directory must be
writable.
The script can be executed by any shell interpreter compatible with
POSIX.2, such as bash(1) or dash(1).
The target argument specifies the type of the target instance document.
Supported values are:
data
Datastore contents (configuration and state data) encapsulated in
<nc:data> document element.
config
A configuration datastore contents encapsulated in <nc:config>
document element.
get-reply
A complete NETCONF message containing a reply to the <nc:get>
operation.
get-config-reply
A complete NETCONF message containing a reply to the
<nc:get-config> operation.
edit-config
A complete NETCONF message containing an <nc:edit-config> request.
Only the RELAX NG schema is generated for this target.
rpc
An RPC request defined in an input YANG module.
rpc-reply
An RPC reply defined in an input YANG module.
notification
An event notification defined in an input YANG module.
The output schemas are contained in the following four files whose
names depend on the arguments basename and target:
basename-target.rng
RELAX NG schema for the target document type.
basename-gdefs-config.rng, basename-gdefs-edit.rng, basename-gdefs.rng
Auxiliary RELAX NG schema containing global named pattern
definitions. The first is generated for "config" and
"get-config-reply" targets, the second for "edit-config" and the
third for the remaining targets.
basename-target.sch
Schematron schema for the target document type. Not generated for
the "edit-config" target.
basename-target.dsrl
DSRL schema for the target document type. Not generated for the
"edit-config" target.
Optional validation of an XML document stored in the file instance
proceeds as follows:
1. Grammatical and datatype constraints are checked using the RELAX NG
schema.
2. The DSRL schema is used for adding default values together with
ancestor containers to the instance document where necessary.
3. Semantic constraints are checked using the Schematron schema. The
skeleton implementation of ISO Schematron[2] by Rick Jelliffe is
included in the distribution and used for this purpose.
Steps 2 and 3 are not performed for the "edit-config" target, or if
step 1 reports any errors.
Option -s may be used together with -v for validating an instance
document without generating the schemas. This assumes that the schemas
are already present in the directory selected by the -d option (current
directory by default). In this case, the basename of the schemas must
be specified using -b basename and the input YANG modules need not be
given. Also, if the DSRL or Schematron schema is missing, the
corresponding step is skipped.
The script uses programs from the libxml2 suite - xmllint(1) for RELAX
NG validation and xsltproc(1) for performing XSLT transformations.
Alternatively, jing(1) can be used for RELAX NG validation (option -j).
If necessary, the script could be easily modified for use with other
RELAX NG validators and/or XSLT1 processors supporting EXSLT.
OPTIONS-b basename
Specifies the basename of files in which the output schemas are
stored. The default is the concatenation of the names of all input
YANG modules connected with the underscore character "_". This
option is mandatory if -s is used.
-d dir
Specifies the directory for output files. By default they are
stored in the current directory.
-h
Displays help screen and exits.
-j
Uses jing(1) for RELAX NG validation instead of the default
xmllint(1).
-L
Interpret the file parameter as the name of a file containing a
server <hello> message. In this case, exactly one file parameter
must be given.
-s
Performs just validation, without (re)generating the schemas. This
option is only allowed together with -v and -b basename must also
be specified.
-t target
Specifies the target XML document type using one of the following
strings as explained above: data (default), config, get-reply,
get-config-reply, edit-config, rpc, rpc-reply or notification.
-v instance
Validates an instance XML document contained in file instance.
FILES
/usr/local/share/yang/xslt/gen-relaxng.xsl
XSLT stylesheet generating RELAX NG schemas.
/usr/local/share/yang/xslt/gen-schematron.xsl
XSLT stylesheet generating Schematron schemas.
/usr/local/share/yang/xslt/gen-dsrl.xsl
XSLT stylesheet generating DSRL schemas.
/usr/local/share/yang/xslt/gen-common.xsl
Common templates for all three XSLT generators.
/usr/local/share/yang/xslt/dsrl2xslt.xsl
Translates a subset of DSRL containing only specification of
default contents to an XSLT stylesheet.
/usr/local/share/yang/xslt/svrl2text.xsl
Translates an SVRL report to plain text.
/usr/local/share/yang/schema/relaxng-lib.rng
RELAX NG library of common NETCONF elements.
/usr/local/share/yang/schema/edit-config-attributes.rng
RELAX NG definitions of <edit-config> attributes.
ENVIRONMENT VARIABLES
PYANG_XSLT_DIR
Alternative directory for XSLT stylesheets. The default is
installation dependent.
PYANG_RNG_LIBDIR
Alternative directory for the RELAX NG library. The default is
installation dependent.
XSLT_OPTS
Options to pass to the XSLT processor when generating the DSDL
schemas. This is mainly useful for debugging.
EXAMPLES
$ yang2dsdl-v dhcp-data.xml dhcp.yang
This command generates the DSDL schemas for the datastore contents
(default data target) as defined by the dhcp.yang module and validates
an instance document stored in the dhcp-data.xml file.
$ yang2dsdl-t rpc rpc-rock.yang
This command generates DSDL schemas for the choice of input parts
(requests) of all RPC operations defined in the module rpc-rock.yang.
DIAGNOSTICSyang2dsdl return codes have the following meaning:
0
No error (normal termination)
1
Error in input parameters
2
Error in DSDL schema generation
3
Instance validation failed
BUGS
1. The logic of command-line arguments may not be able to distinguish
replies to different RPC requests, for example if the replies have
the same top-level element.
SEE ALSOpyang(1), xsltproc(1), xmllint(1), RFC 6110[1], DSDL[3], RELAX NG[4],
ISO Schematron[2].
AUTHOR
Ladislav Lhotka <lhotka@nic.cz>
CZ.NIC
NOTES
1. RFC 6110
http://tools.ietf.org/html/rfc6110
2. ISO Schematron
http://www.schematron.com
3. DSDL
http://www.dsdl.org/
4. RELAX NG
http://www.relaxng.org/
yang2dsdl-1.4.1 2013-11-11 YANG2DSDL(1)
