使用服务组件体系结构和 Apache Tuscany 构建 Mashup

                
<composite xmlns="http://www.osoa.org/xmlns/sca/1.0" name="sample.alerter">

   <service name="AlerterService">
      <binding.rest/>
      <reference>AlertCheckerComponent</reference>
   </service>

   <component name="AlertCheckerComponent">
      <implementation.python module="AlertCheckerImpl" scope="composite"/>
      <reference name="alertConfigService">AlertConfigComponent</reference>
      <reference name="rssCheckerService">RSSCheckerComponent</reference>
      <reference name="popCheckerService">POPCheckerComponent</reference>
   </component>

   <component name="RSSCheckerComponent">
      <implementation.python module="RSSCheckerImpl" scope="composite"/>
   </component>

   <component name="POPCheckerComponent">
      <implementation.python module="POPCheckerImpl" scope="composite"/>
   </component>

   <component name="AlertConfigComponent">
      <implementation.python module="AlertConfigImpl" scope="composite"/>
   </component>
</composite>
      

                
<composite xmlns="http://www.osoa.org/xmlns/sca/1.0" name="sample.display">

   <service name="HTMLDisplayService">
      <binding.rest/>
      <reference>HTMLDisplayComponent</reference>
   </service>

   <component name="HTMLDisplayComponent">
      <implementation.python module="HTMLDisplayImpl" scope="composite"/>
      <reference name="alertService">AlerterService</reference>
      <property name="showNumberOfReadAlerts">20</property>
   </component>

   <reference name="AlerterService">
      <binding.rest/>
   </reference>
</composite>
      

                
import feedparser, datetime, xml.etree.ElementTree, re

# Get new entries from an RSS/Atom feed
def getNewAlerts(rssaddress, lastchecktimestamp):

  print "RSSCheckerImpl.getNewAlerts() called", rssaddress, lastchecktimestamp

  # Get and parse the RSS/Atom data
  d = feedparser.parse(rssaddress)

  newalertsxml = "<alerts " 
  newalertsxml += xmlns=\"http://tuscany.apache.org/samples/alerter\">\n"

  lastcheckdate = datetime.datetime.min
  if lastchecktimestamp:
    lastcheckdate = datetime.datetime.strptime(lastchecktimestamp, 
                                               "%Y-%m-%dT%H:%M:%S")

  # Get default values from the feed attributes
  defaultTitle = d.feed.get('title', 'RSS feed article')
  defaultLink = d.feed.get('link', 'http://incubator.apache.org/tuscany')
  defaultSummary = 'No information provided'

  # Go through each entry in the feed and add it to the XML
  for entry in d.entries:

    if entry.has_key('date'):
      (year, month, day, hour, minute, second, millisecond, 
                           microsecond, tzinfo) = entry.date_parsed
      entrydate = datetime.datetime(year, month, day, hour, minute, second)
    else:
      entrydate = datetime.datetime.now()

    # Only append the latest alerts
    if (entrydate > lastcheckdate) :
      newalertsxml += "<alert><title>" 
      newalertsxml += stripXML(entry.get('title', defaultTitle)) + "</title>\n"
      newalertsxml += "<address>" + entry.get('link', defaultLink)
      newalertsxml += "</address>\n"
      newalertsxml += "<date>" + entrydate.isoformat() + "</date>\n"
      newalertsxml += "<summary>" 
      newalertsxml += stripXML(entry.get('description', defaultSummary))     
      newalertsxml += "</summary>\n"
      newalertsxml += "</alert>\n"

  newalertsxml += "</alerts>"    

  return xml.etree.ElementTree.XML(newalertsxml)

# Strips XML elements and entities out of a supplied string
def stripXML(data):    
  elementsRemoved = re.sub("<.*?>","", data)
  entitiesRemoved = re.sub("&.*?;", " ", elementsRemoved)
  asciiEncoded = entitiesRemoved.encode('ASCII', 'replace')
  returnData = asciiEncoded.replace('&', 'and')
  return returnData
      

                
import xml.etree.ElementTree, datetime

def getAllNewAlerts ():

    returnXML = "<alerts xmlns=\"http://tuscany.apache.org/samples/alerter\">\n"
    returnXML += "</alerts>"
    returnElem = xml.etree.ElementTree.XML(returnXML)

    # Use the alertConfigService to get the configuration
    configElem = alertConfigService.getAlertConfig()

    ns = "./{http://tuscany.apache.org/samples/alerter}"
    for sourceElem in configElem.findall( ns+"source"):

        sourceid = sourceElem.attrib["id"]

        newAlerts = getAlerts(sourceElem)
        if xml.etree.ElementTree.iselement(newAlerts):
            # Add the sourceid to each alert and append to the entire list
            for alert in newAlerts.findall(ns+"alert"):
                alert.attrib["sourceid"] = sourceid
                returnElem.append(alert)

    return returnElem

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