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Viewing changes to txaws/ec2/exception.py

Merge 461960-update-error-wrapper [r=free.ekanayaka] [f=461960]

This branch refactors the error handling for txAWS, not only addressing the
original scope of the ticket (handling ConnectionRefusedError) but also
adding support for handling Amazon-originated 500-errors, non-AWS 400 and 500
errors, and handing improperly configured endpoints that are returning HTML.

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txaws/ec2/exception.py
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# Copyright (c) 2009 Canonical Ltd <duncan.mcgreggor@canonical.com>
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# Licenced under the txaws licence available at /LICENSE in the txaws source.
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from txaws.exception import AWSError
 
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from txaws.exception import AWSError, AWSResponseParseError
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from txaws.util import XML
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        self.original = xml_bytes
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        self.errors = []
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        self.request_id = ""
 
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        self.host_id = ""
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        self.parse()
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    def __str__(self):
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            self.__class__.__name__, self._get_error_code_string())
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    def _set_request_id(self, tree):
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        requestIDNode = tree.find(".//RequestID")
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        if hasattr(requestIDNode, "text"):
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            text = requestIDNode.text
 
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        request_id_node = tree.find(".//RequestID")
 
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        if hasattr(request_id_node, "text"):
 
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            text = request_id_node.text
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            if text:
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                self.requestID = text
 
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                self.request_id = text
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    def _set_errors(self, tree):
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        errorsNode = tree.find(".//Errors")
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        if errorsNode:
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            for error in errorsNode:
 
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    def _set_400_errors(self, tree):
 
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        errors_node = tree.find(".//Errors")
 
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        if errors_node:
 
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            for error in errors_node:
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                data = self._node_to_dict(error)
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                if data:
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                    self.errors.append(data)
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    def _set_host_id(self, tree):
 
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        host_id = tree.find(".//HostID")
 
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        if hasattr(host_id, "text"):
 
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            text = host_id.text
 
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            if text:
 
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                self.host_id = text
 
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    def _set_500_error(self, tree):
 
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        self._set_request_id(tree)
 
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        self._set_host_id(tree)
 
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        data = self._node_to_dict(tree)
 
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        if data:
 
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            self.errors.append(data)
 
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    def _get_error_code_string(self):
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        count = len(self.errors)
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        error_code = self.get_error_codes()
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                data[child.tag] = child.text
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        return data
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    def _check_for_html(self, tree):
 
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        if tree.tag == "html":
 
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            message = "Could not parse HTML in the response."
 
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            raise AWSResponseParseError(message)
 
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    def parse(self, xml_bytes=""):
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        if not xml_bytes:
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            xml_bytes = self.original
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        tree = XML(xml_bytes.strip())
 
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        self._check_for_html(tree)
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        self._set_request_id(tree)
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        self._set_errors(tree)
 
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        if self.status >= 500:
 
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            self._set_500_error(tree)
 
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        else:
 
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            self._set_400_errors(tree)
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    def has_error(self, errorString):
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        for error in self.errors: