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Direktori : /lib/python3/dist-packages/reportlab/platypus/ |
Current File : //lib/python3/dist-packages/reportlab/platypus/doctemplate.py |
#Copyright ReportLab Europe Ltd. 2000-2017 #see license.txt for license details #history https://hg.reportlab.com/hg-public/reportlab/log/tip/src/reportlab/platypus/doctemplate.py __all__ = ( 'ActionFlowable', 'BaseDocTemplate', 'CurrentFrameFlowable', 'FrameActionFlowable', 'FrameBreak', 'Indenter', 'IndexingFlowable', 'LayoutError', 'LCActionFlowable', 'NextFrameFlowable', 'NextPageTemplate', 'NotAtTopPageBreak', 'NullActionFlowable', 'PageAccumulator', 'PageBegin', 'PageTemplate', 'SimpleDocTemplate', ) __version__='3.5.20' __doc__=""" This module contains the core structure of platypus. rlatypus constructs documents. Document styles are determined by DocumentTemplates. Each DocumentTemplate contains one or more PageTemplates which defines the look of the pages of the document. Each PageTemplate has a procedure for drawing the "non-flowing" part of the page (for example the header, footer, page number, fixed logo graphic, watermark, etcetera) and a set of Frames which enclose the flowing part of the page (for example the paragraphs, tables, or non-fixed diagrams of the text). A document is built when a DocumentTemplate is fed a sequence of Flowables. The action of the build consumes the flowables in order and places them onto frames on pages as space allows. When a frame runs out of space the next frame of the page is used. If no frame remains a new page is created. A new page can also be created if a page break is forced. The special invisible flowable NextPageTemplate can be used to specify the page template for the next page (which by default is the one being used for the current frame). """ from reportlab.platypus.flowables import * from reportlab.platypus.flowables import _ContainerSpace from reportlab.lib.units import inch from reportlab.platypus.paragraph import Paragraph from reportlab.platypus.frames import Frame from reportlab.rl_config import defaultPageSize, verbose import reportlab.lib.sequencer from reportlab.pdfgen import canvas from reportlab.lib.utils import isSeq, encode_label, decode_label, annotateException, strTypes try: set except NameError: from sets import Set as set import sys import logging logger = logging.getLogger("reportlab.platypus") class LayoutError(Exception): pass def _fSizeString(f): #used to get size during error messages w=getattr(f,'width',None) if w is None: w=getattr(f,'_width',None) h=getattr(f,'height',None) if h is None: h=getattr(f,'_height',None) #tables in particular may have some nasty large culprit if hasattr(f, '_culprit'): c = ', %s, ' % f._culprit() else: c = '' if w is not None or h is not None: if w is None: w='???' if h is None: h='???' return '(%s x %s)%s' % (w,h,c) return '' def _doNothing(canvas, doc): "Dummy callback for onPage" pass class PTCycle(list): def __new__(cls,*args,**kwds): self = list.__new__(cls,*args,**kwds) self._restart = 0 self._idx = 0 return self @property def next_value(self): v = self[self._idx] self._idx += 1 if self._idx>=len(self): self._idx = self._restart return v @property def peek(self): return self[self._idx] class IndexingFlowable(Flowable): """Abstract interface definition for flowables which might hold references to other pages or themselves be targets of cross-references. XRefStart, XRefDest, Table of Contents, Indexes etc.""" def isIndexing(self): return 1 def isSatisfied(self): return 1 def notify(self, kind, stuff): """This will be called by the framework wherever 'stuff' happens. 'kind' will be a value that can be used to decide whether to pay attention or not.""" pass def beforeBuild(self): """Called by multiBuild before it starts; use this to clear old contents""" pass def afterBuild(self): """Called after build ends but before isSatisfied""" pass class ActionFlowable(Flowable): '''This Flowable is never drawn, it can be used for data driven controls For example to change a page template (from one column to two, for example) use NextPageTemplate which creates an ActionFlowable. ''' def __init__(self,action=()): #must call super init to ensure it has a width and height (of zero), #as in some cases the packer might get called on it... Flowable.__init__(self) if not isSeq(action): action = (action,) self.action = tuple(action) def apply(self,doc): ''' This is called by the doc.build processing to allow the instance to implement its behaviour ''' action = self.action[0] args = tuple(self.action[1:]) arn = 'handle_'+action if arn=="handle_nextPageTemplate" and args[0]=='main': pass try: getattr(doc,arn)(*args) except AttributeError as aerr: if aerr.args[0]==arn: raise NotImplementedError("Can't handle ActionFlowable(%s)" % action) else: raise except: annotateException("\nhandle_%s args=%s"%(action,ascii(args))) def __call__(self): return self def identity(self, maxLen=None): return "ActionFlowable: %s%s" % (str(self.action),self._frameName()) class NullActionFlowable(ActionFlowable): '''an ActionFlowable that does nothing''' def apply(self,doc): pass class LCActionFlowable(ActionFlowable): locChanger = 1 #we cause a frame or page change def wrap(self, availWidth, availHeight): '''Should never be called.''' raise NotImplementedError('%s.wrap should never be called' % self.__class__.__name__) def draw(self): '''Should never be called.''' raise NotImplementedError('%s.draw should never be called' % self.__class__.__name__) class NextFrameFlowable(ActionFlowable): locChanger = 1 #we cause a frame or page change def __init__(self,ix,resume=0): ActionFlowable.__init__(self,('nextFrame',ix,resume)) class CurrentFrameFlowable(LCActionFlowable): def __init__(self,ix,resume=0): ActionFlowable.__init__(self,('currentFrame',ix,resume)) class NullActionFlowable(ActionFlowable): def apply(self,doc): pass class _FrameBreak(LCActionFlowable): ''' A special ActionFlowable that allows setting doc._nextFrameIndex eg story.append(FrameBreak('mySpecialFrame')) ''' def __call__(self,ix=None,resume=0): r = self.__class__(self.action+(resume,)) r._ix = ix return r def apply(self,doc): if getattr(self,'_ix',None): doc.handle_nextFrame(self._ix) ActionFlowable.apply(self,doc) FrameBreak = _FrameBreak('frameEnd') PageBegin = LCActionFlowable('pageBegin') def _evalMeasurement(n): if isinstance(n,str): from reportlab.platypus.paraparser import _num n = _num(n) if isSeq(n): n = n[1] return n class FrameActionFlowable(Flowable): _fixedWidth = _fixedHeight = 1 def __init__(self,*arg,**kw): raise NotImplementedError('%s.__init__ should never be called for abstract Class'%self.__class__.__name__) def frameAction(self,frame): raise NotImplementedError('%s.frameAction should never be called for abstract Class'%self.__class__.__name__) class Indenter(FrameActionFlowable): """Increases or decreases left and right margins of frame. This allows one to have a 'context-sensitive' indentation and makes nested lists way easier. """ _ZEROSIZE=True width=0 height=0 def __init__(self, left=0, right=0): self.left = _evalMeasurement(left) self.right = _evalMeasurement(right) def frameAction(self, frame): frame._leftExtraIndent += self.left frame._rightExtraIndent += self.right class NotAtTopPageBreak(FrameActionFlowable): locChanger = 1 #we cause a frame or page change def __init__(self,nextTemplate=None): self.nextTemplate = nextTemplate def frameAction(self,frame): if not frame._atTop: frame.add_generated_content(PageBreak(nextTemplate=self.nextTemplate)) class NextPageTemplate(ActionFlowable): locChanger = 1 #we cause a frame or page change """When you get to the next page, use the template specified (change to two column, for example) """ def __init__(self,pt): ActionFlowable.__init__(self,('nextPageTemplate',pt)) class PageTemplate: """ essentially a list of Frames and an onPage routine to call at the start of a page when this is selected. onPageEnd gets called at the end. derived classes can also implement beforeDrawPage and afterDrawPage if they want """ def __init__(self,id=None,frames=[],onPage=_doNothing, onPageEnd=_doNothing, pagesize=None, autoNextPageTemplate=None, cropBox=None, artBox=None, trimBox=None, bleedBox=None, ): frames = frames or [] if not isSeq(frames): frames = [frames] assert [x for x in frames if not isinstance(x,Frame)]==[], "frames argument error" self.id = id self.frames = frames self.onPage = onPage self.onPageEnd = onPageEnd self.pagesize = pagesize self.autoNextPageTemplate = autoNextPageTemplate self.cropBox = cropBox self.artBox = artBox self.trimBox = trimBox self.bleedBox = bleedBox def beforeDrawPage(self,canv,doc): """Override this if you want additional functionality or prefer a class based page routine. Called before any flowables for this page are processed.""" pass def checkPageSize(self,canv,doc): """This gets called by the template framework If canv size != template size then the canv size is set to the template size or if that's not available to the doc size. """ #### NEVER EVER EVER COMPARE FLOATS FOR EQUALITY #RGB converting pagesizes to ints means we are accurate to one point #RGB I suggest we should be aiming a little better cp = None dp = None sp = None if canv._pagesize: cp = list(map(int, canv._pagesize)) if self.pagesize: sp = list(map(int, self.pagesize)) if doc.pagesize: dp = list(map(int, doc.pagesize)) if cp!=sp: if sp: canv.setPageSize(self.pagesize) elif cp!=dp: canv.setPageSize(doc.pagesize) for box in 'crop','art','trim','bleed': size = getattr(self,box+'Box',None) if size: canv.setCropBox(size,name=box) def afterDrawPage(self, canv, doc): """This is called after the last flowable for the page has been processed. You might use this if the page header or footer needed knowledge of what flowables were drawn on this page.""" pass def _addGeneratedContent(flowables,frame): S = getattr(frame,'_generated_content',None) if S: flowables[0:0] = S del frame._generated_content class onDrawStr(str): def __new__(cls,value,onDraw,label,kind=None): self = str.__new__(cls,value) self.onDraw = onDraw self.kind = kind self.label = label return self def __getnewargs__(self): return str(self),self.onDraw,self.label,self.kind class PageAccumulator: '''gadget to accumulate information in a page and then allow it to be interrogated at the end of the page''' _count = 0 def __init__(self,name=None): if name is None: name = self.__class__.__name__+str(self.__class__._count) self.__class__._count += 1 self.name = name self.data = [] def reset(self): self.data[:] = [] def add(self,*args): self.data.append(args) def onDrawText(self,*args): return '<onDraw name="%s" label="%s" />' % (self.name,encode_label(args)) def __call__(self,canv,kind,label): self.add(*decode_label(label)) def attachToPageTemplate(self,pt): if pt.onPage: def onPage(canv,doc,oop=pt.onPage): self.onPage(canv,doc) oop(canv,doc) else: def onPage(canv,doc): self.onPage(canv,doc) pt.onPage = onPage if pt.onPageEnd: def onPageEnd(canv,doc,oop=pt.onPageEnd): self.onPageEnd(canv,doc) oop(canv,doc) else: def onPageEnd(canv,doc): self.onPageEnd(canv,doc) pt.onPageEnd = onPageEnd def onPage(self,canv,doc): '''this will be called at the start of the page''' setattr(canv,self.name,self) #push ourselves onto the canvas self.reset() def onPageEnd(self,canv,doc): '''this will be called at the end of a page''' self.pageEndAction(canv,doc) try: delattr(canv,self.name) except: pass self.reset() def pageEndAction(self,canv,doc): '''this should be overridden to do something useful''' pass def onDrawStr(self,value,*args): return onDrawStr(value,self,encode_label(args)) def _ktAllow(f): '''return true if allowed in containers like KeepTogether''' return not (isinstance(f,(_ContainerSpace,DocIf,DocWhile)) or getattr(f,'locChanger',False)) class BaseDocTemplate: """ First attempt at defining a document template class. The basic idea is simple. 1) The document has a list of data associated with it this data should derive from flowables. We'll have special classes like PageBreak, FrameBreak to do things like forcing a page end etc. 2) The document has one or more page templates. 3) Each page template has one or more frames. 4) The document class provides base methods for handling the story events and some reasonable methods for getting the story flowables into the frames. 5) The document instances can override the base handler routines. Most of the methods for this class are not called directly by the user, but in some advanced usages they may need to be overridden via subclassing. EXCEPTION: doctemplate.build(...) must be called for most reasonable uses since it builds a document using the page template. Each document template builds exactly one document into a file specified by the filename argument on initialization. Possible keyword arguments for the initialization: - pageTemplates: A list of templates. Must be nonempty. Names assigned to the templates are used for referring to them so no two used templates should have the same name. For example you might want one template for a title page, one for a section first page, one for a first page of a chapter and two more for the interior of a chapter on odd and even pages. If this argument is omitted then at least one pageTemplate should be provided using the addPageTemplates method before the document is built. - pageSize: a 2-tuple or a size constant from reportlab/lib/pagesizes.pu. Used by the SimpleDocTemplate subclass which does NOT accept a list of pageTemplates but makes one for you; ignored when using pageTemplates. - showBoundary: if set draw a box around the frame boundaries. - leftMargin: - rightMargin: - topMargin: - bottomMargin: Margin sizes in points (default 1 inch). These margins may be overridden by the pageTemplates. They are primarily of interest for the SimpleDocumentTemplate subclass. - allowSplitting: If set flowables (eg, paragraphs) may be split across frames or pages (default: 1) - title: Internal title for document (does not automatically display on any page) - author: Internal author for document (does not automatically display on any page) """ _initArgs = { 'pagesize':defaultPageSize, 'pageTemplates':[], 'showBoundary':0, 'leftMargin':inch, 'rightMargin':inch, 'topMargin':inch, 'bottomMargin':inch, 'allowSplitting':1, 'title':None, 'author':None, 'subject':None, 'creator':None, 'producer':None, 'keywords':[], 'invariant':None, 'pageCompression':None, '_pageBreakQuick':1, 'rotation':0, '_debug':0, 'encrypt': None, 'cropMarks': None, 'enforceColorSpace': None, 'displayDocTitle': None, 'lang': None, 'initialFontName': None, 'initialFontSize': None, 'initialLeading': None, 'cropBox': None, 'artBox': None, 'trimBox': None, 'bleedBox': None, 'keepTogetherClass': KeepTogether, 'hideToolbar': None, 'hideMenubar': None, 'hideWindowUI': None, 'fitWindow': None, 'centerWindow': None, 'nonFullScreenPageMode': None, 'direction': None, 'viewArea': None, 'viewClip': None, 'printArea': None, 'printClip': None, 'printScaling': None, 'duplex': None, } _invalidInitArgs = () _firstPageTemplateIndex = 0 def __init__(self, filename, **kw): """create a document template bound to a filename (see class documentation for keyword arguments)""" self.filename = filename self._nameSpace = dict(doc=self) self._lifetimes = {} for k in self._initArgs.keys(): if k not in kw: v = self._initArgs[k] else: if k in self._invalidInitArgs: raise ValueError("Invalid argument %s" % k) v = kw[k] setattr(self,k,v) p = self.pageTemplates self.pageTemplates = [] self.addPageTemplates(p) # facility to assist multi-build and cross-referencing. # various hooks can put things into here - key is what # you want, value is a page number. This can then be # passed to indexing flowables. self._pageRefs = {} self._indexingFlowables = [] #callback facility for progress monitoring self._onPage = None self._onProgress = None self._flowableCount = 0 # so we know how far to go #infinite loop detection if we start doing lots of empty pages self._curPageFlowableCount = 0 self._emptyPages = 0 self._emptyPagesAllowed = 10 #context sensitive margins - set by story, not from outside self._leftExtraIndent = 0.0 self._rightExtraIndent = 0.0 self._topFlowables = [] self._pageTopFlowables = [] self._frameBGs = [] self._calc() self.afterInit() def _calc(self): self._rightMargin = self.pagesize[0] - self.rightMargin self._topMargin = self.pagesize[1] - self.topMargin self.width = self._rightMargin - self.leftMargin self.height = self._topMargin - self.bottomMargin def setPageCallBack(self, func): 'Simple progress monitor - func(pageNo) called on each new page' self._onPage = func def setProgressCallBack(self, func): '''Cleverer progress monitor - func(typ, value) called regularly''' self._onProgress = func def clean_hanging(self): 'handle internal postponed actions' while len(self._hanging): self.handle_flowable(self._hanging) def addPageTemplates(self,pageTemplates): 'add one or a sequence of pageTemplates' if not isSeq(pageTemplates): pageTemplates = [pageTemplates] #this test below fails due to inconsistent imports! #assert filter(lambda x: not isinstance(x,PageTemplate), pageTemplates)==[], "pageTemplates argument error" for t in pageTemplates: self.pageTemplates.append(t) def handle_documentBegin(self): '''implement actions at beginning of document''' self._hanging = [PageBegin] if isinstance(self._firstPageTemplateIndex,list): self.handle_nextPageTemplate(self._firstPageTemplateIndex) self._setPageTemplate() else: self.pageTemplate = self.pageTemplates[self._firstPageTemplateIndex] self.page = 0 self.beforeDocument() def handle_pageBegin(self): """Perform actions required at beginning of page. shouldn't normally be called directly""" self.page += 1 if self._debug: logger.debug("beginning page %d" % self.page) self.pageTemplate.beforeDrawPage(self.canv,self) self.pageTemplate.checkPageSize(self.canv,self) self.pageTemplate.onPage(self.canv,self) for f in self.pageTemplate.frames: f._reset() self.beforePage() #keep a count of flowables added to this page. zero indicates bad stuff self._curPageFlowableCount = 0 if hasattr(self,'_nextFrameIndex'): del self._nextFrameIndex self.frame = self.pageTemplate.frames[0] self.frame._debug = self._debug self.handle_frameBegin(pageTopFlowables=self._pageTopFlowables) def _setPageTemplate(self): if hasattr(self,'_nextPageTemplateCycle'): #they are cycling through pages'; we keep the index self.pageTemplate = self._nextPageTemplateCycle.next_value elif hasattr(self,'_nextPageTemplateIndex'): self.pageTemplate = self.pageTemplates[self._nextPageTemplateIndex] del self._nextPageTemplateIndex elif self.pageTemplate.autoNextPageTemplate: self.handle_nextPageTemplate(self.pageTemplate.autoNextPageTemplate) self.pageTemplate = self.pageTemplates[self._nextPageTemplateIndex] def _samePT(self,npt): if isSeq(npt): return getattr(self,'_nextPageTemplateCycle',[]) if isinstance(npt,strTypes): return npt == (self.pageTemplates[self._nextPageTemplateIndex].id if hasattr(self,'_nextPageTemplateIndex') else self.pageTemplate.id) if isinstance(npt,int) and 0<=npt<len(self.pageTemplates): if hasattr(self,'_nextPageTemplateIndex'): return npt==self._nextPageTemplateIndex return npt==self.pageTemplates.find(self.pageTemplate) def handle_pageEnd(self): ''' show the current page check the next page template hang a page begin ''' self._removeVars(('page','frame')) self._leftExtraIndent = self.frame._leftExtraIndent self._rightExtraIndent = self.frame._rightExtraIndent self._frameBGs = self.frame._frameBGs #detect infinite loops... if self._curPageFlowableCount == 0: self._emptyPages += 1 else: self._emptyPages = 0 if self._emptyPages >= self._emptyPagesAllowed: if 1: ident = "More than %d pages generated without content - halting layout. Likely that a flowable is too large for any frame." % self._emptyPagesAllowed #leave to keep apart from the raise raise LayoutError(ident) else: pass #attempt to restore to good state else: if self._onProgress: self._onProgress('PAGE', self.canv.getPageNumber()) self.pageTemplate.afterDrawPage(self.canv, self) self.pageTemplate.onPageEnd(self.canv, self) self.afterPage() if self._debug: logger.debug("ending page %d" % self.page) self.canv.setPageRotation(getattr(self.pageTemplate,'rotation',self.rotation)) self.canv.showPage() self._setPageTemplate() if self._emptyPages==0: pass #store good state here self._hanging.append(PageBegin) def handle_pageBreak(self,slow=None): '''some might choose not to end all the frames''' if self._pageBreakQuick and not slow: self.handle_pageEnd() else: n = len(self._hanging) while len(self._hanging)==n: self.handle_frameEnd() def handle_frameBegin(self,resume=0,pageTopFlowables=None): '''What to do at the beginning of a frame''' f = self.frame if f._atTop: boundary = self.frame.showBoundary or self.showBoundary if boundary: self.frame.drawBoundary(self.canv,boundary) f._leftExtraIndent = self._leftExtraIndent f._rightExtraIndent = self._rightExtraIndent f._frameBGs = self._frameBGs if pageTopFlowables: self._hanging.extend(pageTopFlowables) if self._topFlowables: self._hanging.extend(self._topFlowables) def handle_frameEnd(self,resume=0): ''' Handles the semantics of the end of a frame. This includes the selection of the next frame or if this is the last frame then invoke pageEnd. ''' self._removeVars(('frame',)) self._leftExtraIndent = self.frame._leftExtraIndent self._rightExtraIndent = self.frame._rightExtraIndent self._frameBGs = self.frame._frameBGs if hasattr(self,'_nextFrameIndex'): self.frame = self.pageTemplate.frames[self._nextFrameIndex] self.frame._debug = self._debug del self._nextFrameIndex self.handle_frameBegin(resume) else: f = self.frame if hasattr(f,'lastFrame') or f is self.pageTemplate.frames[-1]: self.handle_pageEnd() self.frame = None else: self.frame = self.pageTemplate.frames[self.pageTemplate.frames.index(f) + 1] self.frame._debug = self._debug self.handle_frameBegin() def handle_nextPageTemplate(self,pt): '''On endPage change to the page template with name or index pt''' if isinstance(pt,strTypes): if hasattr(self, '_nextPageTemplateCycle'): del self._nextPageTemplateCycle for t in self.pageTemplates: if t.id == pt: self._nextPageTemplateIndex = self.pageTemplates.index(t) return raise ValueError("can't find template('%s')"%pt) elif isinstance(pt,int): if hasattr(self, '_nextPageTemplateCycle'): del self._nextPageTemplateCycle self._nextPageTemplateIndex = pt elif isSeq(pt): #used for alternating left/right pages #collect the refs to the template objects, complain if any are bad c = PTCycle() for ptn in pt: found = 0 if ptn=='*': #special case name used to short circuit the iteration c._restart = len(c) continue for t in self.pageTemplates: if t.id == ptn: c.append(t) found = 1 if not found: raise ValueError("Cannot find page template called %s" % ptn) if not c: raise ValueError("No valid page templates in cycle") elif c._restart>len(c): raise ValueError("Invalid cycle restart position") #ensure we start on the first one self._nextPageTemplateCycle = c else: raise TypeError("argument pt should be string or integer or list") def _peekNextPageTemplate(self,pt): if isinstance(pt,strTypes): for t in self.pageTemplates: if t.id == pt: return t raise ValueError("can't find template('%s')"%pt) elif isinstance(pt,int): self.pageTemplates[pt] elif isSeq(pt): #used for alternating left/right pages #collect the refs to the template objects, complain if any are bad c = PTCycle() for ptn in pt: found = 0 if ptn=='*': #special case name used to short circuit the iteration c._restart = len(c) continue for t in self.pageTemplates: if t.id == ptn: c.append(t) found = 1 if not found: raise ValueError("Cannot find page template called %s" % ptn) if not c: raise ValueError("No valid page templates in cycle") elif c._restart>len(c): raise ValueError("Invalid cycle restart position") return c.peek else: raise TypeError("argument pt should be string or integer or list") def _peekNextFrame(self): '''intended to be used by extreme flowables''' if hasattr(self,'_nextFrameIndex'): return self.pageTemplate.frames[self._nextFrameIndex] f = self.frame if hasattr(f,'lastFrame') or f is self.pageTemplate.frames[-1]: if hasattr(self,'_nextPageTemplateCycle'): #they are cycling through pages'; we keep the index pageTemplate = self._nextPageTemplateCycle.peek elif hasattr(self,'_nextPageTemplateIndex'): pageTemplate = self.pageTemplates[self._nextPageTemplateIndex] elif self.pageTemplate.autoNextPageTemplate: pageTemplate = self._peekNextPageTemplate(self.pageTemplate.autoNextPageTemplate) else: pageTemplate = self.pageTemplate return pageTemplate.frames[0] else: return self.pageTemplate.frames[self.pageTemplate.frames.index(f) + 1] def handle_nextFrame(self,fx,resume=0): '''On endFrame change to the frame with name or index fx''' if isinstance(fx,strTypes): for f in self.pageTemplate.frames: if f.id == fx: self._nextFrameIndex = self.pageTemplate.frames.index(f) return raise ValueError("can't find frame('%s') in %r(%s) which has frames %r"%(fx,self.pageTemplate,self.pageTemplate.id,[(f,f.id) for f in self.pageTemplate.frames])) elif isinstance(fx,int): self._nextFrameIndex = fx else: raise TypeError("argument fx should be string or integer") def handle_currentFrame(self,fx,resume=0): '''change to the frame with name or index fx''' self.handle_nextFrame(fx,resume) self.handle_frameEnd(resume) def handle_breakBefore(self, flowables): '''preprocessing step to allow pageBreakBefore and frameBreakBefore attributes''' first = flowables[0] # if we insert a page break before, we'll process that, see it again, # and go in an infinite loop. So we need to set a flag on the object # saying 'skip me'. This should be unset on the next pass if hasattr(first, '_skipMeNextTime'): delattr(first, '_skipMeNextTime') return # this could all be made much quicker by putting the attributes # in to the flowables with a defult value of 0 if hasattr(first,'pageBreakBefore') and first.pageBreakBefore == 1: first._skipMeNextTime = 1 first.insert(0, PageBreak()) return if hasattr(first,'style') and hasattr(first.style, 'pageBreakBefore') and first.style.pageBreakBefore == 1: first._skipMeNextTime = 1 flowables.insert(0, PageBreak()) return if hasattr(first,'frameBreakBefore') and first.frameBreakBefore == 1: first._skipMeNextTime = 1 flowables.insert(0, FrameBreak()) return if hasattr(first,'style') and hasattr(first.style, 'frameBreakBefore') and first.style.frameBreakBefore == 1: first._skipMeNextTime = 1 flowables.insert(0, FrameBreak()) return def handle_keepWithNext(self, flowables): "implements keepWithNext" i = 0 n = len(flowables) while i<n and flowables[i].getKeepWithNext() and _ktAllow(flowables[i]): i += 1 if i: if i<n and _ktAllow(flowables[i]): i += 1 K = self.keepTogetherClass(flowables[:i]) mbe = getattr(self,'_multiBuildEdits',None) if mbe: for f in K._content[:-1]: if hasattr(f,'keepWithNext'): mbe((setattr,f,'keepWithNext',f.keepWithNext)) else: mbe((delattr,f,'keepWithNext')) #must get it from a style f.__dict__['keepWithNext'] = 0 else: for f in K._content[:-1]: f.__dict__['keepWithNext'] = 0 del flowables[:i] flowables.insert(0,K) def _fIdent(self,f,maxLen=None,frame=None): if frame: f._frame = frame try: return f.identity(maxLen) finally: if frame: del f._frame def handle_flowable(self,flowables): '''try to handle one flowable from the front of list flowables.''' #allow document a chance to look at, modify or ignore #the object(s) about to be processed self.filterFlowables(flowables) f = flowables[0] if f: self.handle_breakBefore(flowables) self.handle_keepWithNext(flowables) f = flowables[0] del flowables[0] if f is None: return if isinstance(f,PageBreak): npt = f.nextTemplate if npt and not self._samePT(npt): npt=NextPageTemplate(npt) npt.apply(self) self.afterFlowable(npt) if isinstance(f,SlowPageBreak): self.handle_pageBreak(slow=1) else: self.handle_pageBreak() self.afterFlowable(f) elif isinstance(f,ActionFlowable): f.apply(self) self.afterFlowable(f) else: frame = self.frame canv = self.canv #try to fit it then draw it if frame.add(f, canv, trySplit=self.allowSplitting): if not isinstance(f,FrameActionFlowable): self._curPageFlowableCount += 1 self.afterFlowable(f) _addGeneratedContent(flowables,frame) else: if self.allowSplitting: # see if this is a splittable thing S = frame.split(f,canv) n = len(S) else: n = 0 if n: if not isinstance(S[0],(PageBreak,SlowPageBreak,ActionFlowable,DDIndenter)): if not frame.add(S[0], canv, trySplit=0): ident = "Splitting error(n==%d) on page %d in\n%s\nS[0]=%s" % (n,self.page,self._fIdent(f,60,frame),self._fIdent(S[0],60,frame)) #leave to keep apart from the raise raise LayoutError(ident) self._curPageFlowableCount += 1 self.afterFlowable(S[0]) flowables[0:0] = S[1:] # put rest of splitted flowables back on the list _addGeneratedContent(flowables,frame) else: flowables[0:0] = S # put split flowables back on the list else: if hasattr(f,'_postponed'): ident = "Flowable %s%s too large on page %d in frame %r%s of template %r" % \ (self._fIdent(f,60,frame),_fSizeString(f),self.page, self.frame.id, self.frame._aSpaceString(), self.pageTemplate.id) #leave to keep apart from the raise raise LayoutError(ident) # this ought to be cleared when they are finally drawn! f._postponed = 1 mbe = getattr(self,'_multiBuildEdits',None) if mbe: mbe((delattr,f,'_postponed')) flowables.insert(0,f) # put the flowable back self.handle_frameEnd() #these are provided so that deriving classes can refer to them _handle_documentBegin = handle_documentBegin _handle_pageBegin = handle_pageBegin _handle_pageEnd = handle_pageEnd _handle_frameBegin = handle_frameBegin _handle_frameEnd = handle_frameEnd _handle_flowable = handle_flowable _handle_nextPageTemplate = handle_nextPageTemplate _handle_currentFrame = handle_currentFrame _handle_nextFrame = handle_nextFrame def _makeCanvas(self, filename=None, canvasmaker=canvas.Canvas): '''make and return a sample canvas. As suggested by Chris Jerdonek cjerdonek @ bitbucket this allows testing of stringWidths etc. *NB* only the canvases created in self._startBuild will actually be used in the build process. ''' #each distinct pass gets a sequencer self.seq = reportlab.lib.sequencer.Sequencer() canv = canvasmaker(filename or self.filename, pagesize=self.pagesize, invariant=self.invariant, pageCompression=self.pageCompression, enforceColorSpace=self.enforceColorSpace, initialFontName = self.initialFontName, initialFontSize = self.initialFontSize, initialLeading = self.initialLeading, cropBox = self.cropBox, artBox = self.artBox, trimBox = self.trimBox, bleedBox = self.bleedBox, lang = self.lang, ) getattr(canv,'setEncrypt',lambda x: None)(self.encrypt) canv._cropMarks = self.cropMarks canv.setAuthor(self.author) canv.setTitle(self.title) canv.setSubject(self.subject) canv.setCreator(self.creator) canv.setProducer(self.producer) canv.setKeywords(self.keywords) from reportlab.pdfbase.pdfdoc import ( ViewerPreferencesPDFDictionary as VPD, checkPDFBoolean as cPDFB, ) for k,vf in VPD.validate.items(): v = getattr(self,k[0].lower()+k[1:],None) if v is not None: if vf is cPDFB: v = ['false','true'][v] #convert to pdf form of boolean canv.setViewerPreference(k,v) if self._onPage: canv.setPageCallBack(self._onPage) return canv def _startBuild(self, filename=None, canvasmaker=canvas.Canvas): self._calc() self.canv = self._makeCanvas(filename=filename,canvasmaker=canvasmaker) self.handle_documentBegin() def _endBuild(self): self._removeVars(('build','page','frame')) if self._hanging!=[] and self._hanging[-1] is PageBegin: del self._hanging[-1] self.clean_hanging() else: self.clean_hanging() self.handle_pageBreak() if getattr(self,'_doSave',1): self.canv.save() if self._onPage: self.canv.setPageCallBack(None) def build(self, flowables, filename=None, canvasmaker=canvas.Canvas): """Build the document from a list of flowables. If the filename argument is provided then that filename is used rather than the one provided upon initialization. If the canvasmaker argument is provided then it will be used instead of the default. For example a slideshow might use an alternate canvas which places 6 slides on a page (by doing translations, scalings and redefining the page break operations). """ #assert filter(lambda x: not isinstance(x,Flowable), flowables)==[], "flowables argument error" flowableCount = len(flowables) if self._onProgress: self._onProgress('STARTED',0) self._onProgress('SIZE_EST', len(flowables)) self._startBuild(filename,canvasmaker) #pagecatcher can drag in information from embedded PDFs and we want ours #to take priority, so cache and reapply our own info dictionary after the build. canv = self.canv self._savedInfo = canv._doc.info handled = 0 try: canv._doctemplate = self while len(flowables): if self._hanging and self._hanging[-1] is PageBegin and isinstance(flowables[0],PageBreakIfNotEmpty): npt = flowables[0].nextTemplate if npt and not self._samePT(npt): npt=NextPageTemplate(npt) npt.apply(self) self._setPageTemplate() del flowables[0] self.clean_hanging() try: first = flowables[0] self.handle_flowable(flowables) handled += 1 except: #if it has trace info, add it to the traceback message. if hasattr(first, '_traceInfo') and first._traceInfo: exc = sys.exc_info()[1] args = list(exc.args) tr = first._traceInfo args[0] += '\n(srcFile %s, line %d char %d to line %d char %d)' % ( tr.srcFile, tr.startLineNo, tr.startLinePos, tr.endLineNo, tr.endLinePos ) exc.args = tuple(args) raise if self._onProgress: self._onProgress('PROGRESS',flowableCount - len(flowables)) finally: del canv._doctemplate #reapply pagecatcher info canv._doc.info = self._savedInfo self._endBuild() if self._onProgress: self._onProgress('FINISHED',0) def _allSatisfied(self): """Called by multi-build - are all cross-references resolved?""" allHappy = 1 for f in self._indexingFlowables: if not f.isSatisfied(): allHappy = 0 break return allHappy def notify(self, kind, stuff): """Forward to any listeners""" for l in self._indexingFlowables: _canv = getattr(l,'_canv',self) try: if _canv==self: l._canv = self.canv l.notify(kind, stuff) finally: if _canv==self: del l._canv def pageRef(self, label): """hook to register a page number""" if verbose: print("pageRef called with label '%s' on page %d" % ( label, self.page)) self._pageRefs[label] = self.page def multiBuild(self, story, maxPasses = 10, **buildKwds ): """Makes multiple passes until all indexing flowables are happy. Returns number of passes""" self._indexingFlowables = [] #scan the story and keep a copy for thing in story: if thing.isIndexing(): self._indexingFlowables.append(thing) #better fix for filename is a 'file' problem self._doSave = 0 passes = 0 mbe = [] self._multiBuildEdits = mbe.append while 1: passes += 1 if self._onProgress: self._onProgress('PASS', passes) if verbose: sys.stdout.write('building pass '+str(passes) + '...') for fl in self._indexingFlowables: fl.beforeBuild() # work with a copy of the story, since it is consumed tempStory = story[:] self.build(tempStory, **buildKwds) #self.notify('debug',None) for fl in self._indexingFlowables: fl.afterBuild() happy = self._allSatisfied() if happy: self._doSave = 0 self.canv.save() break if passes > maxPasses: raise IndexError("Index entries not resolved after %d passes" % maxPasses) #work through any edits while mbe: e = mbe.pop(0) e[0](*e[1:]) del self._multiBuildEdits if verbose: print('saved') return passes #these are pure virtuals override in derived classes #NB these get called at suitable places by the base class #so if you derive and override the handle_xxx methods #it's up to you to ensure that they maintain the needed consistency def afterInit(self): """This is called after initialisation of the base class.""" pass def beforeDocument(self): """This is called before any processing is done on the document.""" pass def beforePage(self): """This is called at the beginning of page processing, and immediately before the beforeDrawPage method of the current page template.""" pass def afterPage(self): """This is called after page processing, and immediately after the afterDrawPage method of the current page template.""" pass def filterFlowables(self,flowables): '''called to filter flowables at the start of the main handle_flowable method. Upon return if flowables[0] has been set to None it is discarded and the main method returns. ''' pass def afterFlowable(self, flowable): '''called after a flowable has been rendered''' pass _allowedLifetimes = 'page','frame','build','forever' def docAssign(self,var,expr,lifetime): if not isinstance(expr,strTypes): expr=str(expr) expr=expr.strip() var=var.strip() self.docExec('%s=(%s)'%(var.strip(),expr.strip()),lifetime) def docExec(self,stmt,lifetime): stmt=stmt.strip() NS=self._nameSpace K0=list(NS.keys()) try: if lifetime not in self._allowedLifetimes: raise ValueError('bad lifetime %r not in %r'%(lifetime,self._allowedLifetimes)) exec(stmt, NS) except: K1 = [k for k in NS if k not in K0] #the added keys we need to delete for k in K1: del NS[k] annotateException('\ndocExec %s lifetime=%r failed!\n' % (stmt,lifetime)) self._addVars([k for k in NS.keys() if k not in K0],lifetime) def _addVars(self,vars,lifetime): '''add namespace variables to lifetimes lists''' LT=self._lifetimes for var in vars: for v in LT.values(): if var in v: v.remove(var) LT.setdefault(lifetime,set([])).add(var) def _removeVars(self,lifetimes): '''remove namespace variables for with lifetime in lifetimes''' LT=self._lifetimes NS=self._nameSpace for lifetime in lifetimes: for k in LT.setdefault(lifetime,[]): try: del NS[k] except KeyError: pass del LT[lifetime] def docEval(self,expr): try: return eval(expr.strip(),{},self._nameSpace) except: annotateException('\ndocEval %s failed!\n' % expr) class SimpleDocTemplate(BaseDocTemplate): """A special case document template that will handle many simple documents. See documentation for BaseDocTemplate. No pageTemplates are required for this special case. A page templates are inferred from the margin information and the onFirstPage, onLaterPages arguments to the build method. A document which has all pages with the same look except for the first page may can be built using this special approach. """ _invalidInitArgs = ('pageTemplates',) def handle_pageBegin(self): '''override base method to add a change of page template after the firstpage. ''' self._handle_pageBegin() self._handle_nextPageTemplate('Later') def build(self,flowables,onFirstPage=_doNothing, onLaterPages=_doNothing, canvasmaker=canvas.Canvas): """build the document using the flowables. Annotate the first page using the onFirstPage function and later pages using the onLaterPages function. The onXXX pages should follow the signature def myOnFirstPage(canvas, document): # do annotations and modify the document ... The functions can do things like draw logos, page numbers, footers, etcetera. They can use external variables to vary the look (for example providing page numbering or section names). """ self._calc() #in case we changed margins sizes etc frameT = Frame(self.leftMargin, self.bottomMargin, self.width, self.height, id='normal') self.addPageTemplates([PageTemplate(id='First',frames=frameT, onPage=onFirstPage,pagesize=self.pagesize), PageTemplate(id='Later',frames=frameT, onPage=onLaterPages,pagesize=self.pagesize)]) if onFirstPage is _doNothing and hasattr(self,'onFirstPage'): self.pageTemplates[0].beforeDrawPage = self.onFirstPage if onLaterPages is _doNothing and hasattr(self,'onLaterPages'): self.pageTemplates[1].beforeDrawPage = self.onLaterPages BaseDocTemplate.build(self,flowables, canvasmaker=canvasmaker) def progressCB(typ, value): """Example prototype for progress monitoring. This aims to provide info about what is going on during a big job. It should enable, for example, a reasonably smooth progress bar to be drawn. We design the argument signature to be predictable and conducive to programming in other (type safe) languages. If set, this will be called repeatedly with pairs of values. The first is a string indicating the type of call; the second is a numeric value. typ 'STARTING', value = 0 typ 'SIZE_EST', value = numeric estimate of job size typ 'PASS', value = number of this rendering pass typ 'PROGRESS', value = number between 0 and SIZE_EST typ 'PAGE', value = page number of page type 'FINISHED', value = 0 The sequence is STARTING - always called once SIZE_EST - always called once PROGRESS - called often PAGE - called often when page is emitted FINISHED - called when really, really finished some juggling is needed to accurately estimate numbers of pages in pageDrawing mode. NOTE: the SIZE_EST is a guess. It is possible that the PROGRESS value may slightly exceed it, or may even step back a little on rare occasions. The only way to be really accurate would be to do two passes, and I don't want to take that performance hit. """ print('PROGRESS MONITOR: %-10s %d' % (typ, value)) if __name__ == '__main__': from reportlab.lib.styles import _baseFontName, _baseFontNameB def myFirstPage(canvas, doc): from reportlab.lib.colors import red PAGE_HEIGHT = canvas._pagesize[1] canvas.saveState() canvas.setStrokeColor(red) canvas.setLineWidth(5) canvas.line(66,72,66,PAGE_HEIGHT-72) canvas.setFont(_baseFontNameB,24) canvas.drawString(108, PAGE_HEIGHT-108, "TABLE OF CONTENTS DEMO") canvas.setFont(_baseFontName,12) canvas.drawString(4 * inch, 0.75 * inch, "First Page") canvas.restoreState() def myLaterPages(canvas, doc): from reportlab.lib.colors import red PAGE_HEIGHT = canvas._pagesize[1] canvas.saveState() canvas.setStrokeColor(red) canvas.setLineWidth(5) canvas.line(66,72,66,PAGE_HEIGHT-72) canvas.setFont(_baseFontName,12) canvas.drawString(4 * inch, 0.75 * inch, "Page %d" % doc.page) canvas.restoreState() def run(): objects_to_draw = [] from reportlab.lib.styles import ParagraphStyle #from paragraph import Paragraph from reportlab.platypus.doctemplate import SimpleDocTemplate #need a style normal = ParagraphStyle('normal') normal.firstLineIndent = 18 normal.spaceBefore = 6 from reportlab.lib.randomtext import randomText import random for i in range(15): height = 0.5 + (2*random.random()) box = XBox(6 * inch, height * inch, 'Box Number %d' % i) objects_to_draw.append(box) para = Paragraph(randomText(), normal) objects_to_draw.append(para) SimpleDocTemplate('doctemplate.pdf').build(objects_to_draw, onFirstPage=myFirstPage,onLaterPages=myLaterPages) run()