Julius Pfrommer f3432725fc UA2JSON: Fix DataValue example | 5 years ago | |
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examples | 5 years ago | |
CMakeLists.txt | 6 years ago | |
README.md | 6 years ago | |
ua2json.c | 5 years ago |
ua2json is a command line tool to translate between OPC UA JSON encoding and OPC UA binary encoding. ua2json follows the tradition of shell-based unix-tools and provides translation between the binary and JSON encoding formats of OPC UA messages as a reusable building block. Input can be piped through ua2json from stdin to stdout. File input and output is possible as well.
At the core of the OPC UA protocol lies a type system in which the protocol
messages are defined. The built-in data types include integers, strings, and so
on. From these, more complex structures are assembled. For example the
ReadRequest
and ReadResponse
message pair.
Usage: ua2json [encode|decode] [-t dataType] [-o outputFile] [inputFile]
- encode/decode: Translate UA binary input to UA JSON / Translate UA JSON input to UA binary (required)
- dataType: UA DataType of the input (default: Variant)
- outputFile: Output target (default: write to stdout)
- inputFile: Input source (default: read from stdin)
Take the following JSON encoding of a Variant data type instance with a 2x4 matrix of numerical values. Variants can encapsulate scalars and multi-dimensional arrays of any data type.
{
"Type": 3,
"Body": [1,2,3,4,5,6,7,8],
"Dimension": [2, 4]
}
Piping this JSON-encoding through ua2json (and the xxd tool to print the output as hex) yields the binary OPC UA encoding.
$ cat variant.json | ua2json decode -t Variant | xxd
00000000: c308 0000 0001 0203 0405 0607 0802 0000 ................
00000010: 0002 0000 0004 0000 00 .........
The inverse transformation returns the original JSON (modulo pretty-printing).
$ cat variant.bin | ua2json encode -t Variant