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from asyncua import ua |
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2
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3
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class UaFile: |
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def __init__(self, file_node): |
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self._file_node = file_node |
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6
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7
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async def read_file(self): |
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8
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""" |
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:param file_node: node of file object (e.g. node = client.get_node("ns=2;s=nameOfNode") |
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""" |
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handle = await self._open_file(ua.OpenFileMode.Read.value) |
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size = await self._get_file_size() |
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14
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read_node = await self._file_node.get_child("Read") |
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arg1 = ua.Variant(handle, ua.VariantType.UInt32) |
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arg2 = ua.Variant(size, ua.VariantType.Int32) |
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contents = await self._file_node.call_method(read_node, arg1, arg2) |
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await self._close_file(handle) |
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return contents |
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async def _open_file(self, open_mode): |
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""" open file method """ |
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open_node = await self._file_node.get_child("Open") |
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arg = ua.Variant(open_mode, ua.VariantType.Byte) |
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return await self._file_node.call_method(open_node, arg) |
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async def _get_file_size(self): |
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""" gets size of file """ |
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size_node = await self._file_node.get_child("Size") |
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return await size_node.read_value() |
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31
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32
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async def _close_file(self, handle): |
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""" close file method """ |
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read_node = await self._file_node.get_child("Close") |
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arg1 = ua.Variant(handle, ua.VariantType.UInt32) |
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return await self._file_node.call_method(read_node, arg1) |
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FreeOpcUa /
opcua-asyncio
