用Python写一个文本转HTML的脚本

在 实验楼 上看的，自己看了一下感觉用处很大，代码也不难懂，特分享一下。

给定一个.txt文件，将其转换成HTML网页。

我们先来编写代码：

#!/usr/bin/python
# encoding: utf-8
#util.py
def lines(file):
    """
    生成器,在文本最后加一空行
    """
    for line in file: yield line
    yield '\n'

def blocks(file):
    """
    生成器,生成单独的文本块
    """
    block = []
    for line in lines(file):
        if line.strip():
            block.append(line)
        elif block:
            yield ''.join(block).strip()
            block = []

#!/usr/bin/python
# encoding: utf-8
#handlers.py
class Handler:
    """
    处理程序父类
    """
    def callback(self, prefix, name, *args):
        method = getattr(self, prefix + name, None)
        if callable(method): return method(*args)

    def start(self, name):
        self.callback('start_', name)

    def end(self, name):
        self.callback('end_', name)

    def sub(self, name):
        def substitution(match):
            result = self.callback('sub_', name, match)
            if result is None: result = match.group(0)
            return result
        return substitution

class HTMLRenderer(Handler):
    """
    HTML 处理程序,给文本块加相应的 HTML 标记
    """
    def start_document(self):
        print ('')

    def end_document(self):
        print ('')

    def start_paragraph(self):
        print ('
')

    def end_paragraph(self):
        print ('
')

    def start_heading(self):
        print ('
')

    def end_heading(self):
        print ('
')

    def start_list(self):
        print ('
')

    def end_list(self):
        print ('
')

    def start_listitem(self):
        print ('
')

    def end_listitem(self):
        print ('
')

    def start_title(self):
        print ('
')

    def end_title(self):
        print ('
')

    def sub_emphasis(self, match):
        return '%s' % match.group(1)

    def sub_url(self, match):
        return '%s' % (match.group(1), match.group(1))

    def sub_mail(self, match):
        return '%s' % (match.group(1), match.group(1))

    def feed(self, data):
        print (data)

#!/usr/bin/python
# encoding: utf-8
#rules.py
class Rule:
    """
    规则父类
    """
    def action(self, block, handler):
        """
        加标记
        """
        handler.start(self.type)
        handler.feed(block)
        handler.end(self.type)
        return True

class HeadingRule(Rule):
    """
    一号标题规则
    """
    type = 'heading'
    def condition(self, block):
        """
        判断文本块是否符合规则
        """
        return not '\n' in block and len(block) <= 70 and not block[-1] == ':'

class TitleRule(HeadingRule):
    """
    二号标题规则
    """
    type = 'title'
    first = True

    def condition(self, block):
        if not self.first: return False
        self.first = False
        return HeadingRule.condition(self, block);

class ListItemRule(Rule):
    """
    列表项规则
    """
    type = 'listitem'
    def condition(self, block):
        return block[0] == '-'

    def action(self, block, handler):
        handler.start(self.type)
        handler.feed(block[1:].strip())
        handler.end(self.type)
        return True

class ListRule(ListItemRule):
    """
    列表规则
    """
    type = 'list'
    inside = False
    def condition(self, block):
        return True

    def action(self, block, handler):
        if not self.inside and ListItemRule.condition(self, block):
            handler.start(self.type)
            self.inside = True
        elif self.inside and not ListItemRule.condition(self, block):
            handler.end(self.type)
            self.inside = False
        return False

class ParagraphRule(Rule):
    """
    段落规则
    """
    type = 'paragraph'

    def condition(self, block):
        return True

#!/usr/bin/python
# encoding: utf-8
#makeup.py
import sys, re
from handlers import *
from util import *
from rules import *

class Parser:
    """
    解析器父类
    """
    def __init__(self, handler):
        self.handler = handler
        self.rules = []
        self.filters = []

    def addRule(self, rule):
        """
        添加规则
        """
        self.rules.append(rule)

    def addFilter(self, pattern, name):
        """
        添加过滤器
        """
        def filter(block, handler):
            return re.sub(pattern, handler.sub(name), block)
        self.filters.append(filter)

    def parse(self, file):
        """
        解析
        """
        self.handler.start('document')
        for block in blocks(file):
            for filter in self.filters:
                block = filter(block, self.handler)
            for rule in self.rules:
                if rule.condition(block):
                    last = rule.action(block, self.handler)
                    if last: break
        self.handler.end('document')

class BasicTextParser(Parser):
    """
    纯文本解析器
    """
    def __init__(self, handler):
        Parser.__init__(self, handler)
        self.addRule(ListRule())
        self.addRule(ListItemRule())
        self.addRule(TitleRule())
        self.addRule(HeadingRule())
        self.addRule(ParagraphRule())

        self.addFilter(r'\*(.+?)\*', 'emphasis')
        self.addFilter(r'(http://[\.a-zA-Z/]+)', 'url')
        self.addFilter(r'([\.a-zA-Z]+@[\.a-zA-Z]+[a-zA-Z]+)', 'mail')

"""
运行程序
"""
handler = HTMLRenderer()
parser = BasicTextParser(handler)
parser.parse(sys.stdin)

写完之后，让我们来测试一下。

看，大功告成