jthan is whining about adding him to acknowledgments

aif/config.py

@@ -1,19 +1,145 @@
 import os
+import re
 ##
+import requests
 from lxml import etree
 
 # https://stackoverflow.com/questions/30232031/how-can-i-strip-namespaces-out-of-an-lxml-tree/30233635#30233635 ?
 
+_patterns = {'raw': re.compile(r'^\s*(?P<xml><(\?xml|aif)\s+.*)\s*$', re.DOTALL|re.MULTILINE),
+             'remote': re.compile(r'^(?P<uri>(?P<proto>(https?|ftps?)://)(?P<path>.*))\s*$'),
+             'local': re.compile(r'^(file://)?(?P<path>(/?[^/]+)+/?)$')}
+
 class Config(object):
-    def __init__(self):
+    def __init__(self, *args, **kwargs):
+        self.tree = None
+        self.namespaced_tree = None
         self.xml = None
+        self.namespaced_xml = None
+        self.raw = None
+        self.xsd = None
 
-    def parseLocalFile(self, fpath):
-        fpath = os.path.abspath(os.path.expanduser(fpath))
-        pass
+    def main(self, validate = True):
+        self.fetch()
+        self.parseRaw()
+        if validate:
+            self.validate()
 
-    def parseRemoteFile(self, url):
-        pass
+        return()
 
-    def parseRawContent(self, content):
+    def fetch(self):  # Just a fail-safe; this is overridden by specific subclasses.
         pass
+        return()
+
+    def getXSD(self, xsdpath = None):
+        raw_xsd = None
+        if xsdpath:
+            xsdpath = os.path.abspath(os.path.expanduser(xsdpath))
+            if not os.path.isfile(xsdpath):
+                raise ValueError(('An explicit XSD path was specified but '
+                                  'does not exist on the local filesystem'))
+            with open(xsdpath, 'rb') as fh:
+                raw_xsd = fh.read()
+        else:
+            xsi = self.xml.nsmap.get('xsi', 'http://www.w3.org/2001/XMLSchema-instance')
+            schemaLocation = '{{{0}}}schemaLocation'.format(xsi)
+            schemaURL = self.xml.attrib.get(schemaLocation,
+                                            'https://aif-ng.io/aif.xsd?ref={0}'.format(self.xml.attrib['version']))
+            req = requests.get(schemaURL)
+            if not req.ok():
+                raise RuntimeError('Could not download XSD')
+            raw_xsd = req.content
+        self.xsd = etree.XMLSchema(etree.XML(raw_xsd))
+        return()
+
+    def parseRaw(self):
+        self.tree = etree.parse(self.raw)
+        self.namespaced_tree = etree.parse(self.raw)
+        self.xml = self.tree.getroot()
+        self.namespaced_xml = self.namespaced_tree.getroot()
+        self.tree.xinclude()
+        self.namespaced_tree.xinclude()
+        return()
+
+    def stripNS(self):
+        # https://stackoverflow.com/questions/30232031/how-can-i-strip-namespaces-out-of-an-lxml-tree/30233635#30233635
+        for x in (self.tree, self.xml):
+            for e in x.xpath("descendant-or-self::*[namespace-uri()!='']"):
+                e.tag = etree.QName(e).localname
+        return()
+
+    def validate(self):
+        if not self.xsd:
+            self.getXSD()
+
+        return()
+
+
+class LocalFile(Config):
+    def __init__(self, path, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.source = ['local', _patterns['local'].search(path).group('path')]
+
+    def fetch(self):
+        self.source[1] = os.path.abspath(os.path.expanduser(self.source[1]))
+        if not os.path.isfile(self.source[1]):
+            raise ValueError('{0} does not exist'.format(self.source[1]))
+        with open(self.source[1], 'rb') as fh:
+            self.raw = fh.read()
+        return()
+
+
+class RemoteFile(Config):
+    def __init__(self, uri, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.source = ('remote', uri)
+
+    def fetch(self):
+        r = requests.get(self.source[1])
+        if not r.ok():
+            raise RuntimeError('Could not download XML')
+        self.raw = r.content
+        return()
+
+
+class ConfigStr(Config):
+    def __init__(self, rawxml, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.source = ('raw', rawxml)
+
+    def fetch(self):
+        self.raw = self.source[1].encode('utf-8')
+        return()
+
+class ConfigBin(Config):
+    def __init__(self, rawbinaryxml, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.source = ('raw_binary', rawbinaryxml)
+
+    def fetch(self):
+        self.raw = self.source[1]
+        return()
+
+
+def getConfig(cfg_ref, validate = True):
+    cfgobj = None
+    # This is kind of gross.
+    for configtype, pattern in _patterns.items():
+        try:
+            if pattern.search(cfg_ref):
+                if configtype == 'raw':
+                    cfgobj = ConfigStr(cfg_ref)
+                elif configtype == 'remote':
+                    cfgobj = RemoteFile(cfg_ref)
+                elif configtype == 'local':
+                    cfgobj = LocalFile(cfg_ref)
+                if cfgobj:
+                    break
+        except TypeError:
+            ptrn = re.compile(_patterns['raw'].pattern.encode('utf-8'))
+            if not ptrn.search(cfg_ref):
+                raise ValueError('Received junk data for cfg_ref')
+            else:
+                cfgobj = ConfigBin(cfg_ref)
+                break
+    return(cfgobj)