7b666d818d50a01a97e465fe2d602af1d54e807b
   1#
   2#   format.py
   3#   
   4#   This file contains global functions for formatting and printing data. This
   5#   file should be imported into individual log-parsing scripts located in
   6#   logs/*. Data is formatted in HTML or plaintext. Writing to disk and/or
   7#   emailng data is left to __main__.py.
   8#
   9
  10import os
  11import re
  12import locale
  13from string import Template
  14from math import floor, ceil
  15from tabulate import tabulate
  16
  17import logparse
  18from logparse import interface, util, mail, config
  19
  20import logging
  21logger = logging.getLogger(__name__)
  22
  23
  24locale.setlocale(locale.LC_ALL, '') # inherit system locale
  25#DEG = "°".encode('unicode_escape')
  26DEG = u'\N{DEGREE SIGN}'
  27CEL = "C"
  28TIMEFMT = "%X"
  29DATEFMT = "%x"
  30CORNERCHARS_DOUBLE = ['╚', '╝', '╗', '╔']
  31CORNERCHARS_SINGLE = ['└', '┘', '┐', '┌']
  32LINECHARS_DOUBLE = ['║', '═']
  33LINECHARS_SINGLE = ['│', '─']
  34JXNCHARS_DOUBLE = ['╠', '╣', '╦', '╩', '╬']
  35JXNCHARS_SINGLE = ['├', '┤', '┬', '┴', '┼']
  36BULLET = "• "
  37INDENT = "  "
  38
  39global VARSUBST
  40
  41def init_var():
  42    global VARSUBST
  43    css_path = config.prefs.get("html", "css")
  44    if config.prefs.getboolean("html", "css-relpath"):
  45        if interface.argparser.parse_args().no_write:
  46            css_path = os.path.relpath(css_path, ".")
  47        elif interface.argparser.parse_args().destination:
  48            css_path = os.path.relpath(css_path, interface.argparser.parse_args().destination())
  49        elif config.prefs.get("logparse", "output"):
  50            css_path = os.path.relpath(css_path, config.prefs.get("logparse", "output"))
  51    VARSUBST = {
  52        "title": config.prefs.get("logparse", "title"),
  53        "date": interface.start.strftime(DATEFMT),
  54        "time": interface.start.strftime(TIMEFMT),
  55        "hostname": util.hostname(config.prefs.get("logparse", "hostname-path")),
  56        "version": logparse.__version__,
  57        "css": css_path
  58    }
  59
  60
  61class Output:
  62    """
  63    Base class for a data processor. 
  64    """
  65    
  66    def __init__(self):
  67        self.content = ""
  68        self.destination = ""
  69
  70    def append(self, content):
  71        """
  72        Add a string
  73        """
  74        self.content += content
  75
  76    def write(self, destination=""):
  77        """
  78        Output contents into a file
  79        """
  80        if destination == "":
  81            destination = self.destination
  82        if destination == "":
  83            logger.warning("No destination path provided")
  84            return 1
  85        with open(destination, 'w') as f:
  86            f.write(self.content)
  87            logger.info("Written output to {}".format(destination))
  88
  89    def print_stdout(self, lines=False):
  90        """
  91        Echo the contents to the console
  92        """
  93        print()
  94        if lines:
  95            line = PlaintextLine(linewidth=config.prefs.getint("plain", "linewidth"), double=True)
  96            print(line.draw())
  97        print(self.content)
  98        if lines:
  99            print(line.draw())
 100        print()
 101
 102
 103
 104class PlaintextOutput(Output):
 105    """
 106    Processes & outputs data in a plaintext form which can be read with cat or plaintext email.
 107    """
 108
 109    def __init__(self, linewidth=80):
 110        self.content = ""
 111        self.destination = ""
 112        self.linewidth = linewidth;
 113
 114    def append_header(self, template=''):
 115        """
 116        Print details with some primitive formatting
 117        """
 118        box = PlaintextBox(content=Template("$title $version on $hostname\n\n$time $date").safe_substitute(VARSUBST), vpadding=2, hpadding="\t\t", linewidth=self.linewidth)
 119        line = PlaintextLine(self.linewidth)
 120        self.append(box.draw() + line.draw())
 121
 122    def append_footer(self):
 123        """
 124        Append a horizontal line and some details
 125        """
 126        self.append(PlaintextLine(self.linewidth, vpadding=1).draw())
 127        self.append(Template("$hostname $time $date").safe_substitute(VARSUBST))
 128
 129    def append_section(self, section):
 130        """
 131        Call the appropriate methods to format a section (provided by a parser).
 132        This should be run by interface.py after every instance of parse_log().
 133        """
 134        self.append(PlaintextBox(content=section.title, double=False, fullwidth=False, vpadding=0, hpadding=" ").draw())
 135        self.append('\n'*2)
 136        for data in section.data:
 137            self.append(self._fmt_data(data.subtitle, data.items))
 138            self.append('\n')
 139        for table in section.tables:
 140            self.append(table.draw_plain())
 141        self.append("\n")
 142
 143    def _fmt_data(self, subtitle, data = None):   # write title and data
 144        """
 145        Format the properties of a data object into usable plaintext form with a few fancy symbols/formatting tricks.
 146        Subtitle is required, data is not. If only subtitle is supplied or subtitle + one data item, a single line will be printed.
 147        """
 148        if (subtitle == ""):
 149            logger.warning("No subtitle provided.. skipping section")
 150            return
 151
 152        if (data == None or len(data) == 0):
 153            logger.debug("No data provided.. just printing subtitle")
 154            return subtitle + '\n'
 155        else:
 156            logger.debug("Received data " + str(data))
 157            subtitle += ':'
 158            if (len(data) == 1):
 159                return subtitle + ' ' + data[0] + '\n'
 160            else:
 161                itemoutput = subtitle + '\n'
 162                for datum in data:
 163                    datum = BULLET + datum
 164                    if len(datum) > self.linewidth - 3:
 165                        words = datum.split()
 166                        if max(map(len, words)) > self.linewidth - len(INDENT):
 167                            continue
 168                        res, part, others = [], words[0], words[1:]
 169                        for word in others:
 170                            if 1 + len(word) > self.linewidth - len(part):
 171                                res.append(part)
 172                                part = word
 173                            else:
 174                                part += ' ' + word
 175                        if part:
 176                            res.append(part)
 177                        datum = ('\n    ').join(res)
 178                    datum = INDENT + datum
 179                    itemoutput += datum + '\n'
 180                return itemoutput
 181
 182class HtmlOutput(Output):
 183    """
 184    Process and output data in HTML format.
 185    All HTML formatting functions now reside in this class to differentiate them from plaintext.
 186    """
 187
 188    def __init__(self):
 189        self.content = ""
 190        self.destination = ""
 191        self.css = ""
 192        self._embedded = ""
 193
 194    def embed_css(self, css):
 195        """
 196        Convert stylesheet to inline tags
 197        """
 198        if not self._embedded:
 199            self._embedded = mail.mailprep(self.content, css)
 200        return self._embedded
 201
 202    def append_header(self, template):
 203        """
 204        Insert variables into header template file and append HTML tags
 205        """
 206        headercontent = Template(open(template, 'r').read())
 207        self.append(headercontent.safe_substitute(VARSUBST))
 208        self.append(opentag('div', id='main'))
 209
 210    def append_footer(self):
 211        """
 212        Close HTML tags that were opened in the template.
 213        TODO: add footer template similar to header template.
 214        """
 215        self.append(closetag('div') + closetag('body') + closetag('html'))
 216
 217    def append_section(self, section):
 218        """
 219        Call the appropriate methods to generate HTML tags for a section (provided by a parser).
 220        This should be run by interface.py after every instance of parse_log().
 221        """
 222        self.append(opentag('div', 1, section.title, 'section'))
 223        self.append(self._gen_title(section.title))
 224        for data in section.data:
 225            self.append(self._fmt_data(data.subtitle, data.items))
 226        for table in section.tables:
 227            self.append(table.draw_html())
 228        self.append(closetag('div', 1))
 229
 230    def _gen_title(self, title):
 231        """
 232        Format the title for a section
 233        """
 234        if (title == '' or '\n' in title):
 235            logger.error("Invalid title")
 236            raise ValueError 
 237        logger.debug("Writing title for " + title)
 238        return tag('h2', False, title)
 239
 240    def _fmt_data(self, subtitle, data = None):
 241        """
 242        Format the properties of a data object into usable HTML tags.
 243        Subtitle is required, data is not. If only subtitle is supplied or subtitle + one data item, a single line will be printed.
 244        """
 245        if (subtitle == ""):
 246            logger.warning("No subtitle provided.. skipping section")
 247            return
 248
 249        if (data == None or len(data) == 0):
 250            logger.debug("No data provided.. just printing subtitle")
 251            return tag('p', False, subtitle)
 252        else:
 253            logger.debug("Received data " + str(data))
 254            subtitle += ':'
 255            if (len(data) == 1):
 256                return tag('p', False, subtitle + ' ' + data[0])
 257            else:
 258                output = ""
 259                output += tag('p', False, subtitle)
 260                output += opentag('ul', 1)
 261                coderegex = re.compile('`(.*)`')
 262                for datum in data:
 263                    if datum == "" or datum == None:
 264                        continue
 265                    datum = coderegex.sub(r"<code>\1</code>", str(datum))
 266                    output += tag('li', False, datum)
 267                output += closetag('ul', True)
 268                return output
 269
 270
 271class Section:
 272    """
 273    Each parser should output a Section() which contains the title and returned data.
 274    """
 275
 276    def __init__(self, title):
 277        self.title = title
 278        self.data = []
 279        self.tables = []
 280
 281    def append_data(self, data):
 282        self.data.append(data)
 283
 284    def append_table(self, table):
 285        self.tables.append(table)
 286
 287
 288class Data:
 289    """
 290    Each section (parser) can have one or more Data() objects which are essentially glorified lists.
 291    """
 292    
 293    def __init__(self, subtitle="", items=[]):
 294        self.subtitle = subtitle
 295        self.items = items 
 296
 297    def truncl(self, limit):      # truncate list
 298        """
 299        Truncate self.items to a specified value and state how many items are hidden.
 300        """
 301        if (len(self.items) > limit):
 302            more = len(self.items) - limit
 303            if more == 1:
 304                return 0
 305            self.items = self.items[:limit]
 306            self.items.append("+ {0} more".format(str(more)))
 307
 308    def orderbyfreq(self):
 309        """
 310        Order a list by frequency of each item, then remove duplicates and append frequency in parentheses.
 311        """
 312        unsorted = list(self.items)
 313        self.items = ["{0} ({1})".format(y, unsorted.count(y)) for y in sorted(set(unsorted), key = lambda x: -unsorted.count(x))]
 314
 315class Table(object):
 316    """
 317    A wrapper for python-tabulate's Tabulate type.
 318    """
 319    
 320    def __init__(self, double=False, borders=False, hpadding=" ", maxwidth=80, headers=[]):
 321        self.rows =  []     # List of row objects
 322        self.keymap = {}    # For fast lookup of row by value of first column 
 323        self.double = double
 324        self.borders = borders
 325        self.align_cols = []
 326        self.hpadding = hpadding
 327        self.maxwidth = maxwidth
 328        self.headers = headers
 329        self._align_cols = []
 330
 331    def add_row(self, row):
 332
 333        self.rows.append(row)
 334        if len(row.columns) > 0:
 335            self.keymap[row.columns[0]] = row
 336
 337        logger.debug("Added row with {0} columns".format(str(len(row.columns))))
 338
 339    def align_column(self, i, align):
 340        while len(self._align_cols) -1 < i:
 341            self._align_cols.append("")
 342        self._align_cols[i] = align
 343        for row in self.rows:
 344            row.columns[i].align = align
 345        logger.debug("Column alignment is now {0}".format(str(self._align_cols)))
 346
 347    def _gen_list(self):
 348        hierarchy = []
 349        for row in self.rows:
 350            row_data = []
 351            for column in row.columns:
 352                row_data.append(column.content)
 353            hierarchy.append(row_data)
 354        return hierarchy
 355
 356    def draw_html(self):
 357        output = tabulate(self._gen_list(), self.headers, tablefmt="html", colalign=tuple(self._align_cols))
 358        return output
 359
 360    def draw_plain(self):
 361        output = tabulate(self._gen_list(), self.headers, tablefmt="fancy_grid" if self.borders else "plain", colalign=tuple(self._align_cols))
 362        return output + "\n"*2
 363
 364
 365class Table0(object):
 366    """
 367    A two-dimensional information display.
 368    This is a hacky implementation - Table() now relies on the Tabulate package which is much more reliable.
 369    """
 370
 371    def __init__(self, double=False, borders=True, hpadding="+", maxwidth=80):
 372        self.rows =  []     # List of row objects
 373        self.keymap = {}    # For fast lookup of row by value of first column 
 374        self.double = double
 375        self.borders = borders
 376        self.align_cols = []
 377        self.hpadding = hpadding
 378        self.maxwidth = maxwidth
 379        self._colwidths = []
 380
 381    def add_row(self, row):
 382        self.rows.append(row)
 383        for i, col in enumerate(row.columns):
 384            if len(self._colwidths) >= i + 1:
 385                self._colwidths[i] = max([self._colwidths[i], len(col.content)])
 386            else:
 387                self._colwidths.append(len(col.content))
 388        logger.debug("Added row with {0} columns. Column widths are now {1}.".format(str(len(row.columns)), str(self._colwidths)))
 389        if len(row.columns) > 0:
 390            self.keymap[row.columns[0]] = row
 391    
 392    def align_column(self, i, align):
 393        for row in self.rows:
 394            row.columns[i].align = align
 395        
 396
 397    def draw_html(self):
 398        output = ""
 399        output += opentag("table", True, cl="data_table") 
 400        for row in self.rows:
 401            if row.header:
 402                output += opentag("th", block=True, cl="header")
 403            else:
 404                output += opentag("tr", block=True)
 405            for column in row.columns:
 406                output += tag("td", content=column.content, style={"text-align": column.align} if column.align else {})
 407            if row.header:
 408                output += closetag("th", True)
 409            else:
 410                output += closetag("tr", True)
 411        output += closetag("table", True)
 412        logger.debug("Built table with {0} rows and {1} columns".format(str(len(self.rows)), str(max([x.n for x in self.rows]))))
 413        return output
 414
 415    def draw_plain(self):
 416        output = ""
 417        cols = [list(x) for x in zip(self.rows)]
 418        logger.debug("Cols are " + str(cols))
 419
 420        if self.double == True:
 421            cornerchars = CORNERCHARS_DOUBLE
 422            linechars = LINECHARS_DOUBLE
 423            jxnchars = JXNCHARS_DOUBLE
 424        else:
 425            cornerchars = CORNERCHARS_SINGLE
 426            linechars = LINECHARS_SINGLE
 427            jxnchars = JXNCHARS_SINGLE
 428        
 429        lengths = []
 430        row_lengths = []
 431        for row in self.rows:
 432            for i, col in enumerate(row.columns):
 433                if len(lengths) >= i + 1:
 434                    lengths[i] = max([lengths[i], len(col.content)])
 435                else:
 436                    lengths.append(len(col.content))
 437
 438        logger.debug("Lengths are " + str(lengths))
 439
 440        for i, row in enumerate(self.rows):
 441            l = (len(INDENT) + len(self.hpadding)*2*len(row.columns) + ((1+len(row.columns)) if self.borders else 0) + sum([len(col.content) for col in row.columns]))
 442            if l > self.maxwidth:
 443                logger.debug("Line overflow for cell in row {0} of table".format(str(i)))
 444                words = row.columns[-1].content.split()
 445                if max(map(len, words)) > self.maxwidth:
 446                    continue
 447                res, part, others = [], words[0], words[1:]
 448                for word in others:
 449                    if l - len(word) < self.maxwidth:
 450                        res.append(part)
 451                        part = word
 452                    else:
 453                        part += ' ' + word
 454                if part:
 455                    res.append(part)
 456                self._colwidths[-1] = max([len(f) for f in res] + [len(r.columns[-1].content) for r in self.rows if r != row])
 457                if self.borders:
 458                    row.columns[-1].content = res[0][:-1] + self.hpadding + " "*(self._colwidths[-1]-len(res[0])+1) + linechars[0]
 459                    for fragment in res[1:]:
 460                        row.columns[-1].content += "\n" + INDENT + "".join([(linechars[0] + self.hpadding + " "*x + self.hpadding) for x in lengths]) + linechars[0] + self.hpadding + fragment + " " * (max(self._colwidths) - len(fragment))
 461
 462        if self.borders:
 463            top = INDENT + cornerchars[3] + jxnchars[2].join(linechars[1] * (l+2) for l in self._colwidths) + cornerchars[2] + "\n"
 464            bottom = INDENT + cornerchars[0] + jxnchars[3].join(linechars[1] * (l+2) for l in self._colwidths) + cornerchars[1] + "\n"
 465            rowtext = INDENT + linechars[0] + linechars[0].join("{:>%d}" % l for l in self._colwidths) + linechars[0] + "\n"
 466            line = INDENT + jxnchars[0] + jxnchars[4].join(linechars[1] * (l+2) for l in self._colwidths) + jxnchars[1] + "\n"
 467        else:
 468            top = bottom = line = ""
 469            rowtext = " ".join("{:>%d}" % l for l in self._colwidths) + "\n"
 470
 471        for i, row in enumerate(self.rows):
 472            logger.debug("Processing row {0} of {1}".format(str(i), str(len(self.rows)-1)))
 473            row_output = ""
 474            if i == 0:
 475                row_output += top
 476            row_output += (INDENT + linechars[0] if self.borders else "")
 477            for j, column in enumerate(row.columns):
 478                if column.align == "right":
 479                    cell_output = self.hpadding + " "*(self._colwidths[j]-len(column.content)) + column.content + self.hpadding + (linechars[0] if self.borders else "")
 480                elif column.align == "left":
 481                    cell_output = self.hpadding + column.content + " "*(self._colwidths[j]-len(column.content)) + self.hpadding + (linechars[0] if self.borders else "")
 482                elif column.align == "center":
 483                    n_whitespace = (self._colwidths[j]-len(column.content))/2
 484                    cell_output = self.hpadding + " "*(floor(n_whitespace) if len(column.content) % 2 == 0 else ceil(n_whitespace)) + column.content + " "*(ceil(n_whitespace) if len(column.content) % 2 == 0 else floor(n_whitespace)) + self.hpadding + (linechars[0] if self.borders else "")
 485                else:
 486                    logger.warning("Couldn't find alignment value for cell {0} of row {1} with content \"{2}\"".format(str(j), str(i), column.content()))
 487                    continue
 488                row_output += cell_output
 489                if len(row_output) > self.maxwidth:
 490                    logger.warning("Line overflow for row {0} of table".format(str(i)))
 491
 492            output += row_output + "\n"
 493            if i == len(self.rows)-1:
 494                output += (bottom if self.borders else "")
 495            else:
 496                output += (line if self.borders else "")
 497
 498        return output
 499
 500class Row(object):
 501    
 502    def __init__(self, columns=[], header=False):
 503        self.columns = columns
 504        self.header = header
 505        self.n = len(self.columns)
 506
 507    def add_column(self, column):
 508        self.columns.append(column)
 509        self.n += 1
 510
 511    def rm_column(self, column):
 512        self.remove(column)
 513        self.n -= 1
 514
 515class Column(object):
 516
 517    def __init__(self, content="", align="right"):
 518        self.content = content
 519        self.align = align
 520
 521class PlaintextLine:
 522    """
 523    Draw a horizontal line for plain text format, with optional padding/styling.
 524    """
 525
 526    def __init__(self, linewidth=80, double=True, vpadding=1, hpadding=""):
 527        self.linewidth = linewidth
 528        self.double = double
 529        self.vpadding = vpadding
 530        self.hpadding = hpadding
 531
 532    def draw(self):
 533        line = (LINECHARS_DOUBLE[1] if self.double else LINECHARS_SINGLE[1])
 534        return "\n" * self.vpadding + self.hpadding +  line * (self.linewidth - 2 * len(self.hpadding)) + self.hpadding + "\n" * self.vpadding
 535
 536
 537class PlaintextBox:
 538    """
 539    Draw a rectangular box around text, with customisable padding/size/style
 540    """
 541
 542    def __init__(self, content="", double=True, fullwidth=True, linewidth=80, hpadding="\t", vpadding=1):
 543        self.content = content
 544        self.fullwidth = fullwidth
 545        self.linewidth = linewidth
 546        self.hpadding = hpadding 
 547        self.vpadding = vpadding
 548        self.double = double
 549
 550    def draw(self):
 551
 552        if self.double == True:
 553            cornerchars = CORNERCHARS_DOUBLE
 554            linechars = LINECHARS_DOUBLE
 555        else:
 556            cornerchars = CORNERCHARS_SINGLE
 557            linechars = LINECHARS_SINGLE
 558
 559        # Check hpadding has a definite width
 560        self.hpadding = self.hpadding.replace("\t", " "*4)
 561
 562        # Calculate number of characters per line
 563        contentlines = self.content.splitlines()
 564        contentwidth = int((self.linewidth if self.linewidth > 0 else 80) if self.content.splitlines() else len(max(contentlines, key=len)))
 565        logger.debug("Contentwidth is {0}".format(str(contentwidth)))
 566        logger.debug("Longest line is {0}".format(len(max(contentlines, key=len))))
 567        contentwidth += -2*(len(self.hpadding)+1)
 568        if not self.fullwidth:
 569            longestline = len(max(contentlines, key=len))
 570            if longestline <= self.linewidth - 2*(len(self.hpadding)+1):
 571                contentwidth = longestline
 572
 573        # Split lines that are too long
 574        for i, line in enumerate(contentlines):
 575            if len(line) > contentwidth:
 576                words = line.split()
 577                if max(map(len, words)) > contentwidth:
 578                    continue
 579                res, part, others = [], words[0], words[1:]
 580                for word in others:
 581                    if len(' ') + len(word) > contentwidth - len(part):
 582                        res.append(part)
 583                        part = word
 584                    else:
 585                        part += ' ' + word
 586                if part:
 587                    res.append(part)
 588                contentlines[i] = res
 589
 590        # Flatten list
 591        #   Note list comprehension doesn't work here, so we must iterate through each item
 592        newlines = []
 593        for line in contentlines:
 594            if isinstance(line, list):
 595                for subline in line:
 596                    newlines.append(subline)
 597            else:
 598                newlines.append(line)
 599        contentlines = newlines
 600               
 601        # Add vertical padding
 602        for _ in range(self.vpadding):
 603            contentlines.insert(0, ' '*contentwidth)
 604            contentlines.append(' '*contentwidth)
 605
 606        # Insert horizontal padding on lines that are too short
 607        contentlines = [linechars[0] + self.hpadding + x + ' '*(self.linewidth-(len(x)+2*len(self.hpadding)+2) if len(x) < contentwidth else 0) + self.hpadding + linechars[0] for x in contentlines]
 608        contentlines.insert(0, cornerchars[3] + linechars[1] * (contentwidth + len(self.hpadding)*2) + cornerchars[2])
 609        contentlines.append(cornerchars[0] + linechars[1] * (contentwidth + len(self.hpadding)*2) + cornerchars[1])
 610        return ('\n').join(contentlines)
 611
 612
 613def backticks(l):
 614    return ["`" + x + "`" for x in l]
 615
 616
 617def plural(noun, quantity, print_quantity=True):
 618    """
 619    Return "1 noun" or "n nouns"
 620    """
 621    if print_quantity:
 622        if (quantity == 1):
 623            return(str(quantity) + " " + noun)
 624        else:
 625            return(str(quantity) + " " + noun + "s")
 626    else:
 627        if (quantity == 1):
 628            return noun
 629        else:
 630            return noun + "s"
 631
 632
 633def parsesize(num, suffix='B'):
 634    """
 635    Return human-readable size from number of bytes
 636    """
 637    for unit in ['','Ki','Mi','Gi','Ti','Pi','Ei','Zi']:
 638        if abs(num) < 1024.0:
 639            return "%3.1f %s%s" % (num, unit, suffix)
 640        num /= 1024.0
 641    return "%.1f%s%s" % (num, 'Yi', suffix)
 642
 643
 644def fsubject(subject):
 645    """
 646    Replace variables in the title template provided in config
 647    """
 648    r = Template(subject).safe_substitute(VARSUBST)
 649    logger.debug("Returning subject line " + r)
 650    return r
 651
 652def opentag(tag, block=False, id=None, cl=None, style=None):
 653    """
 654    Write HTML opening tag
 655    """
 656    output = ""
 657    if block:
 658        output += '\n'
 659    output += '<' + tag
 660    if id:
 661        output += " id='" + id + "'"
 662    if cl:
 663        output += " class='" + cl + "'"
 664    if style:
 665        output += " style='"
 666        output += " ".join("{0}: {1};".format(attr, value) for attr, value in style.items())
 667        output += "'"
 668    output += '>'
 669    if block:
 670        output += '\n'
 671    return output
 672
 673def closetag(tag, block=False):
 674    """
 675    Write HTML closing tag
 676    """
 677    if block:
 678        return "\n</" + tag + ">\n"
 679    else:
 680        return "</" + tag + ">"
 681
 682def tag(tag, block=False, content="", id=None, cl=None, style=None):
 683    """
 684    Write HTML opening tag, content, and closing tag
 685    """
 686    o = opentag(tag, block, id, cl, style)
 687    c = closetag(tag, block)
 688    return o + content + c
 689