# ------------------------------------------------------------------------------ # Appy is a framework for building applications in the Python language. # Copyright (C) 2007 Gaetan Delannay # This program is free software; you can redistribute it and/or # modify it under the terms of the GNU General Public License # as published by the Free Software Foundation; either version 2 # of the License, or (at your option) any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,USA. # ------------------------------------------------------------------------------ import re from appy.pod import PodError, XML_SPECIAL_CHARS from appy.pod.elements import * from appy.pod.actions import IfAction, ElseAction, ForAction, VariableAction, \ NullAction from appy.shared import xmlPrologue # ------------------------------------------------------------------------------ class ParsingError(Exception): pass # ParsingError-related constants ----------------------------------------------- ELEMENT = 'identifies the part of the document that will be impacted ' \ 'by the command. It must be one of %s.' % str(PodElement.POD_ELEMS) FOR_EXPRESSION = 'must be of the form: {name} in {expression}. {name} must be '\ 'a Python variable name. It is the name of the iteration ' \ 'variable. {expression} is a Python expression that, when ' \ 'evaluated, produces a Python sequence (tuple, string, list, '\ 'etc).' POD_STATEMENT = 'A Pod statement has the ' \ 'form: do {element} [{command} {expression}]. {element} ' + \ ELEMENT + ' Optional {command} can be "if" ' \ '(conditional inclusion of the element) or "for" (multiple ' \ 'inclusion of the element). For an "if" command, {expression} '\ 'is any Python expression. For a "for" command, {expression} '+\ FOR_EXPRESSION FROM_CLAUSE = 'A "from" clause has the form: from {expression}, where ' \ '{expression} is a Python expression that, when evaluated, ' \ 'produces a valid chunk of odt content that will be inserted ' \ 'instead of the element that is the target of the note.' BAD_STATEMENT_GROUP = 'Syntax error while parsing a note whose content is ' \ '"%s". In a note, you may specify at most 2 lines: a ' \ 'pod statement and a "from" clause. ' + POD_STATEMENT + \ ' ' + FROM_CLAUSE BAD_STATEMENT = 'Syntax error for statement "%s". ' + POD_STATEMENT BAD_ELEMENT = 'Bad element "%s". An element ' + ELEMENT BAD_MINUS = "The '-' operator can't be used with element '%s'. It can only be "\ "specified for elements among %s." ELEMENT_NOT_FOUND = 'Action specified element "%s" but available elements ' \ 'in this part of the document are %s.' BAD_FROM_CLAUSE = 'Syntax error in "from" clause "%s". ' + FROM_CLAUSE DUPLICATE_NAMED_IF = 'An "if" statement with the same name already exists.' ELSE_WITHOUT_IF = 'No previous "if" statement could be found for this "else" ' \ 'statement.' ELSE_WITHOUT_NAMED_IF = 'I could not find an "if" statement named "%s".' BAD_FOR_EXPRESSION = 'Bad "for" expression "%s". A "for" expression ' + \ FOR_EXPRESSION BAD_VAR_EXPRESSION = 'Bad variable definition "%s". A variable definition ' \ 'must have the form {name} = {expression}. {name} must be a Python-' \ 'compliant variable name. {expression} is a Python expression. When ' \ 'encountering such a statement, pod will define, in the specified part ' \ 'of the document, a variable {name} whose value will be the evaluated ' \ '{expression}.' EVAL_EXPR_ERROR = 'Error while evaluating expression "%s". %s' NULL_ACTION_ERROR = 'There was a problem with this action. Possible causes: ' \ '(1) you specified no action (ie "do text") while not ' \ 'specifying any from clause; (2) you specified the from ' \ 'clause on the same line as the action, which is not ' \ 'allowed (ie "do text from ...").' # ------------------------------------------------------------------------------ class BufferIterator: def __init__(self, buffer): self.buffer = buffer self.remainingSubBufferIndexes = self.buffer.subBuffers.keys() self.remainingElemIndexes = self.buffer.elements.keys() self.remainingSubBufferIndexes.sort() self.remainingElemIndexes.sort() def hasNext(self): return self.remainingSubBufferIndexes or self.remainingElemIndexes def next(self): nextSubBufferIndex = None if self.remainingSubBufferIndexes: nextSubBufferIndex = self.remainingSubBufferIndexes[0] nextExprIndex = None if self.remainingElemIndexes: nextExprIndex = self.remainingElemIndexes[0] # Compute min between nextSubBufferIndex and nextExprIndex if (nextSubBufferIndex != None) and (nextExprIndex != None): res = min(nextSubBufferIndex, nextExprIndex) elif (nextSubBufferIndex == None) and (nextExprIndex != None): res = nextExprIndex elif (nextSubBufferIndex != None) and (nextExprIndex == None): res = nextSubBufferIndex # Update "remaining" lists if res == nextSubBufferIndex: self.remainingSubBufferIndexes = self.remainingSubBufferIndexes[1:] resDict = self.buffer.subBuffers elif res == nextExprIndex: self.remainingElemIndexes = self.remainingElemIndexes[1:] resDict = self.buffer.elements return res, resDict[res] # ------------------------------------------------------------------------------ class Buffer: '''Abstract class representing any buffer used during rendering.''' elementRex = re.compile('([\w-]+:[\w-]+)\s*(.*?)>', re.S) def __init__(self, env, parent): self.parent = parent self.subBuffers = {} # ~{i_bufferIndex: Buffer}~ self.env = env def addSubBuffer(self, subBuffer=None): if not subBuffer: subBuffer = MemoryBuffer(self.env, self) self.subBuffers[self.getLength()] = subBuffer subBuffer.parent = self return subBuffer def removeLastSubBuffer(self): subBufferIndexes = self.subBuffers.keys() subBufferIndexes.sort() lastIndex = subBufferIndexes.pop() del self.subBuffers[lastIndex] def write(self, something): pass # To be overridden def getLength(self): pass # To be overridden def dumpStartElement(self, elem, attrs={}): self.write('<%s' % elem) for name, value in attrs.items(): self.write(' %s="%s"' % (name, value)) self.write('>') def dumpEndElement(self, elem): self.write('' % elem) def dumpElement(self, elem, content=None, attrs={}): '''For dumping a whole element at once.''' self.dumpStartElement(elem, attrs) if content: self.dumpContent(content) self.dumpEndElement(elem) def dumpContent(self, content): '''Dumps string p_content into the buffer.''' for c in content: if XML_SPECIAL_CHARS.has_key(c): self.write(XML_SPECIAL_CHARS[c]) else: self.write(c) def dumpAttribute(self, name, value): self.write(''' %s="%s" ''' % (name, value)) # ------------------------------------------------------------------------------ class FileBuffer(Buffer): def __init__(self, env, result): Buffer.__init__(self, env, None) self.result = result self.content = file(result, 'w') self.content.write(xmlPrologue) def getLength(self): return 0 # getLength is used to manage insertions into sub-buffers. But in the case # of a FileBuffer, we will only have 1 sub-buffer at a time, and we don't # care about where it will be inserted into the FileBuffer. def write(self, something): self.content.write(something.encode('utf-8')) def addExpression(self, expression): try: self.dumpContent(Expression(expression).evaluate(self.env.context)) except Exception, e: PodError.dump(self, EVAL_EXPR_ERROR % (expression, e), dumpTb=False) def pushSubBuffer(self, subBuffer): pass # ------------------------------------------------------------------------------ class MemoryBuffer(Buffer): actionRex = re.compile('(?:(\w+)\s*\:\s*)?do\s+(\w+)(-)?' \ '(?:\s+(for|if|else|with)\s*(.*))?') forRex = re.compile('\s*([\w\-_]+)\s+in\s+(.*)') varRex = re.compile('\s*([\w\-_]+)\s*=\s*(.*)') def __init__(self, env, parent): Buffer.__init__(self, env, parent) self.content = u'' self.elements = {} self.action = None def addSubBuffer(self, subBuffer=None): sb = Buffer.addSubBuffer(self, subBuffer) self.content += ' ' # To avoid having several subbuffers referenced at # the same place within this buffer. return sb def getFileBuffer(self): if isinstance(self.parent, FileBuffer): res = self.parent else: res = self.parent.getFileBuffer() return res def getLength(self): return len(self.content) def write(self, thing): self.content += thing def getIndex(self, podElemName): res = -1 for index, podElem in self.elements.iteritems(): if podElem.__class__.__name__.lower() == podElemName: if index > res: res = index return res def getMainElement(self): res = None if self.elements.has_key(0): res = self.elements[0] return res def isMainElement(self, elem): res = False mainElem = self.getMainElement() if mainElem and (elem == mainElem.OD.elem): res = True # Check if this element is not found again within the buffer for index, podElem in self.elements.iteritems(): if podElem.OD: if (podElem.OD.elem == mainElem.OD.elem) and (index != 0): res = False break return res def unreferenceElement(self, elem): # Find last occurrence of this element elemIndex = -1 for index, podElem in self.elements.iteritems(): if podElem.OD: if (podElem.OD.elem == elem) and (index > elemIndex): elemIndex = index del self.elements[elemIndex] def pushSubBuffer(self, subBuffer): '''Sets p_subBuffer at the very end of the buffer.''' subIndex = None for index, aSubBuffer in self.subBuffers.iteritems(): if aSubBuffer == subBuffer: subIndex = index break if subIndex != None: # Indeed, it is possible that this buffer is not referenced # in the parent (if it is a temp buffer generated from a cut) del self.subBuffers[subIndex] self.subBuffers[self.getLength()] = subBuffer self.content += u' ' def transferAllContent(self): '''Transfer all content to parent.''' if isinstance(self.parent, FileBuffer): # First unreference all elements for index in self.getElementIndexes(expressions=False): del self.elements[index] self.evaluate() else: # Transfer content in itself oldParentLength = self.parent.getLength() self.parent.write(self.content) # Transfer elements for index, podElem in self.elements.iteritems(): self.parent.elements[oldParentLength + index] = podElem # Transfer subBuffers for index, buf in self.subBuffers.iteritems(): self.parent.subBuffers[oldParentLength + index] = buf # Empty the buffer MemoryBuffer.__init__(self, self.env, self.parent) # Change buffer position wrt parent self.parent.pushSubBuffer(self) def addElement(self, elem): newElem = PodElement.create(elem) self.elements[self.getLength()] = newElem if isinstance(newElem, Cell) or isinstance(newElem, Table): newElem.tableInfo = self.env.getTable() def addExpression(self, expression): # Create the POD expression expr = Expression(expression) expr.expr = expression self.elements[self.getLength()] = expr self.content += u' ' # To be sure that an expr and an elem can't be found # at the same index in the buffer. def createAction(self, statementGroup): '''Tries to create an action based on p_statementGroup. If the statement is not correct, r_ is -1. Else, r_ is the index of the element within the buffer that is the object of the action.''' res = -1 try: # Check the whole statement group if not statementGroup or (len(statementGroup) > 2): raise ParsingError(BAD_STATEMENT_GROUP % str(statementGroup)) # Check the statement statement = statementGroup[0] aRes = self.actionRex.match(statement) if not aRes: raise ParsingError(BAD_STATEMENT % statement) statementName, podElem, minus, actionType, subExpr = aRes.groups() if not (podElem in PodElement.POD_ELEMS): raise ParsingError(BAD_ELEMENT % podElem) if minus and (not podElem in PodElement.MINUS_ELEMS): raise ParsingError( BAD_MINUS % (podElem, PodElement.MINUS_ELEMS)) indexPodElem = self.getIndex(podElem) if indexPodElem == -1: raise ParsingError( ELEMENT_NOT_FOUND % (podElem, str([ e.__class__.__name__.lower() \ for e in self.elements.values()]))) podElem = self.elements[indexPodElem] # Check the 'from' clause fromClause = None source = 'buffer' if len(statementGroup) > 1: fromClause = statementGroup[1] source = 'from' if not fromClause.startswith('from '): raise ParsingError(BAD_FROM_CLAUSE % fromClause) fromClause = fromClause[5:] # Create the action if actionType == 'if': self.action = IfAction(statementName, self, subExpr, podElem, minus, source, fromClause) self.env.ifActions.append(self.action) if self.action.name: # We must register this action as a named action if self.env.namedIfActions.has_key(self.action.name): raise ParsingError(DUPLICATE_NAMED_IF) self.env.namedIfActions[self.action.name] = self.action elif actionType == 'else': if not self.env.ifActions: raise ParsingError(ELSE_WITHOUT_IF) # Does the "else" action reference a named "if" action? ifReference = subExpr.strip() if ifReference: if not self.env.namedIfActions.has_key(ifReference): raise ParsingError(ELSE_WITHOUT_NAMED_IF % ifReference) linkedIfAction = self.env.namedIfActions[ifReference] # This "else" action "consumes" the "if" action: this way, # it is not possible to define two "else" actions related to # the same "if". del self.env.namedIfActions[ifReference] self.env.ifActions.remove(linkedIfAction) else: linkedIfAction = self.env.ifActions.pop() self.action = ElseAction(statementName, self, None, podElem, minus, source, fromClause, linkedIfAction) elif actionType == 'for': forRes = MemoryBuffer.forRex.match(subExpr.strip()) if not forRes: raise ParsingError(BAD_FOR_EXPRESSION % subExpr) iter, subExpr = forRes.groups() self.action = ForAction(statementName, self, subExpr, podElem, minus, iter, source, fromClause) elif actionType == 'with': varRes = MemoryBuffer.varRex.match(subExpr.strip()) if not varRes: raise ParsingError(BAD_VAR_EXPRESSION % subExpr) varName, subExpr = varRes.groups() self.action = VariableAction(statementName, self, subExpr, podElem, minus, varName, source, fromClause) else: # null action if not fromClause: raise ParsingError(NULL_ACTION_ERROR) self.action = NullAction(statementName, self, None, podElem, None, source, fromClause) res = indexPodElem except ParsingError, ppe: PodError.dump(self, ppe, removeFirstLine=True) return res def cut(self, index, keepFirstPart): '''Cuts this buffer into 2 parts. Depending on p_keepFirstPart, the 1st (from 0 to index-1) or the second (from index to the end) part of the buffer is returned as a MemoryBuffer instance without parent; the other part is self.''' res = MemoryBuffer(self.env, None) # Manage buffer meta-info (elements, expressions, subbuffers) iter = BufferIterator(self) subBuffersToDelete = [] elementsToDelete = [] mustShift = False while iter.hasNext(): itemIndex, item = iter.next() if keepFirstPart: if itemIndex >= index: newIndex = itemIndex-index if isinstance(item, MemoryBuffer): res.subBuffers[newIndex] = item subBuffersToDelete.append(itemIndex) else: res.elements[newIndex] = item elementsToDelete.append(itemIndex) else: if itemIndex < index: if isinstance(item, MemoryBuffer): res.subBuffers[itemIndex] = item subBuffersToDelete.append(itemIndex) else: res.elements[itemIndex] = item elementsToDelete.append(itemIndex) else: mustShift = True if elementsToDelete: for elemIndex in elementsToDelete: del self.elements[elemIndex] if subBuffersToDelete: for subIndex in subBuffersToDelete: del self.subBuffers[subIndex] if mustShift: elements = {} for elemIndex, elem in self.elements.iteritems(): elements[elemIndex-index] = elem self.elements = elements subBuffers = {} for subIndex, buf in self.subBuffers.iteritems(): subBuffers[subIndex-index] = buf self.subBuffers = subBuffers # Manage content if keepFirstPart: res.write(self.content[index:]) self.content = self.content[:index] else: res.write(self.content[:index]) self.content = self.content[index:] return res def getElementIndexes(self, expressions=True): res = [] for index, elem in self.elements.iteritems(): condition = isinstance(elem, Expression) if not expressions: condition = not condition if condition: res.append(index) return res def transferActionIndependentContent(self, actionElemIndex): # Manage content to transfer to parent buffer if actionElemIndex != 0: actionIndependentBuffer = self.cut(actionElemIndex, keepFirstPart=False) actionIndependentBuffer.parent = self.parent actionIndependentBuffer.transferAllContent() self.parent.pushSubBuffer(self) # Manage content to transfer to a child buffer actionElemIndex = self.getIndex( self.action.elem.__class__.__name__.lower()) # We recompute actionElemIndex because after cut it may have changed elemIndexes = self.getElementIndexes(expressions=False) elemIndexes.sort() if elemIndexes.index(actionElemIndex) != (len(elemIndexes)-1): # I must create a sub-buffer with the impactable elements after # the action-related element childBuffer = self.cut(elemIndexes[elemIndexes.index( actionElemIndex)+1], keepFirstPart=True) self.addSubBuffer(childBuffer) res = childBuffer else: res = self return res def getStartIndex(self, removeMainElems): '''When I must dump the buffer, sometimes (if p_removeMainElems is True), I must dump only a subset of it. This method returns the start index of the buffer part I must dump.''' if removeMainElems: # Find the start position of the deepest element to remove deepestElem = self.action.elem.DEEPEST_TO_REMOVE pos = self.content.find('<%s' % deepestElem.elem) pos = pos + len(deepestElem.elem) # Now we must find the position of the end of this start tag, # skipping potential attributes. inAttrValue = False # Are we parsing an attribute value ? endTagFound = False # Have we found the end of this tag ? while not endTagFound: pos += 1 nextChar = self.content[pos] if (nextChar == '>') and not inAttrValue: # Yes we have it endTagFound = True elif nextChar == '"': inAttrValue = not inAttrValue res = pos + 1 else: res = 0 return res def getStopIndex(self, removeMainElems): '''This method returns the stop index of the buffer part I must dump.''' if removeMainElems: ns = self.env.namespaces deepestElem = self.action.elem.DEEPEST_TO_REMOVE pos = self.content.rfind('' % deepestElem.getFullName(ns)) res = pos else: res = self.getLength() return res reTagContent = re.compile('<(?P

[\w-]+):(?P[\w-]+)(.*?)>.*', re.S) def evaluate(self, subElements=True, removeMainElems=False): result = self.getFileBuffer() if not subElements: # Dump the root tag in this buffer, but not its content. res = self.reTagContent.match(self.content.strip()) if not res: result.write(self.content) else: g = res.group result.write('<%s:%s%s>' % (g(1),g(2),g(3),g(1),g(2))) else: iter = BufferIterator(self) currentIndex = self.getStartIndex(removeMainElems) while iter.hasNext(): index, evalEntry = iter.next() result.write(self.content[currentIndex:index]) currentIndex = index + 1 if isinstance(evalEntry, Expression): try: result.dumpContent(evalEntry.evaluate(self.env.context)) except Exception, e: PodError.dump(result, EVAL_EXPR_ERROR % ( evalEntry.expr, e), dumpTb=False) else: # It is a subBuffer if evalEntry.action: evalEntry.action.execute() else: result.write(evalEntry.content) stopIndex = self.getStopIndex(removeMainElems) if currentIndex < (stopIndex-1): result.write(self.content[currentIndex:stopIndex]) # ------------------------------------------------------------------------------