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"""Module with all classes related to links. |
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Links are low level abstractions representing connections between two |
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interfaces. |
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""" |
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import json |
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from uuid import uuid4 |
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from kytos.core.common import GenericEntity |
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class Link(GenericEntity): |
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"""Define a link between two Endpoints.""" |
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def __init__(self, endpoint_a, endpoint_b): |
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"""Create a Link instance and set its attributes.""" |
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self.endpoint_a = endpoint_a |
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self.endpoint_b = endpoint_b |
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self._uuid = uuid4() |
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super().__init__() |
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def __eq__(self, other): |
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"""Check if two instances of Link are equal.""" |
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return ((self.endpoint_a == other.endpoint_a and |
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self.endpoint_b == other.endpoint_b) or |
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(self.endpoint_a == other.endpoint_b and |
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self.endpoint_b == other.endpoint_a)) |
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@property |
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def id(self): # pylint: disable=invalid-name |
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"""Return id from Link intance. |
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Returns: |
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string: link id. |
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""" |
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return "{}".format(self._uuid) |
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@property |
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def available_tags(self): |
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"""Return the available tags for the link. |
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Based on the endpoint tags. |
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""" |
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return [tag for tag in self.endpoint_a.available_tags if tag in |
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self.endpoint_b.available_tags] |
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def enable(self): |
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"""Enable this link instance. |
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Also enable the link's interfaces and the switches they're attached to. |
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""" |
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self.endpoint_a.enable() |
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self.endpoint_b.enable() |
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self.enabled = True |
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def use_tag(self, tag): |
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"""Remove a specific tag from available_tags if it is there.""" |
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if self.is_tag_available(tag): |
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self.endpoint_a.use_tag(tag) |
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self.endpoint_b.use_tag(tag) |
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return True |
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return False |
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def is_tag_available(self, tag): |
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"""Check if a tag is available.""" |
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return (self.endpoint_a.is_tag_available(tag) and |
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self.endpoint_b.is_tag_available(tag)) |
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def get_next_available_tag(self): |
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"""Return the next available tag if exists.""" |
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for tag in self.endpoint_a.available_tags: |
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if tag in self.endpoint_b.available_tags: |
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return tag |
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return False |
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def make_tag_available(self, tag): |
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"""Add a specific tag in available_tags.""" |
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if not self.is_tag_available(tag): |
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self.endpoint_a.make_tag_available(tag) |
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self.endpoint_b.make_tag_available(tag) |
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else: |
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return False |
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def as_dict(self): |
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"""Return the Link as a dictionary.""" |
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return {'id': self.id, |
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'endpoint_a': self.endpoint_a.as_dict(), |
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'endpoint_b': self.endpoint_b.as_dict(), |
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'metadata': self.metadata, |
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'active': self.active, |
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'enabled': self.enabled} |
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def as_json(self): |
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"""Return the Link as a JSON string.""" |
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return json.dumps(self.as_dict()) |
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