# templater.py - template expansion for output
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from i18n import _
import sys, os
import util, config, templatefilters, parser, error
# template parsing
elements = {
"(": (20, ("group", 1, ")"), ("func", 1, ")")),
",": (2, None, ("list", 2)),
"|": (5, None, ("|", 5)),
"%": (6, None, ("%", 6)),
")": (0, None, None),
"symbol": (0, ("symbol",), None),
"string": (0, ("string",), None),
"end": (0, None, None),
}
def tokenizer(data):
program, start, end = data
pos = start
while pos < end:
c = program[pos]
if c.isspace(): # skip inter-token whitespace
pass
elif c in "(,)%|": # handle simple operators
yield (c, None, pos)
elif (c in '"\'' or c == 'r' and
program[pos:pos + 2] in ("r'", 'r"')): # handle quoted strings
if c == 'r':
pos += 1
c = program[pos]
decode = lambda x: x
else:
decode = lambda x: x.decode('string-escape')
pos += 1
s = pos
while pos < end: # find closing quote
d = program[pos]
if d == '\\': # skip over escaped characters
pos += 2
continue
if d == c:
yield ('string', decode(program[s:pos]), s)
break
pos += 1
else:
raise error.ParseError(_("unterminated string"), s)
elif c.isalnum() or c in '_':
s = pos
pos += 1
while pos < end: # find end of symbol
d = program[pos]
if not (d.isalnum() or d == "_"):
break
pos += 1
sym = program[s:pos]
yield ('symbol', sym, s)
pos -= 1
elif c == '}':
pos += 1
break
else:
raise error.ParseError(_("syntax error"), pos)
pos += 1
yield ('end', None, pos)
def compiletemplate(tmpl, context):
parsed = []
pos, stop = 0, len(tmpl)
p = parser.parser(tokenizer, elements)
while pos < stop:
n = tmpl.find('{', pos)
if n < 0:
parsed.append(("string", tmpl[pos:]))
break
if n > 0 and tmpl[n - 1] == '\\':
# escaped
parsed.append(("string", tmpl[pos:n - 1] + "{"))
pos = n + 1
continue
if n > pos:
parsed.append(("string", tmpl[pos:n]))
pd = [tmpl, n + 1, stop]
parseres, pos = p.parse(pd)
parsed.append(parseres)
return [compileexp(e, context) for e in parsed]
def compileexp(exp, context):
t = exp[0]
if t in methods:
return methods[t](exp, context)
raise error.ParseError(_("unknown method '%s'") % t)
# template evaluation
def getsymbol(exp):
if exp[0] == 'symbol':
return exp[1]
raise error.ParseError(_("expected a symbol"))
def getlist(x):
if not x:
return []
if x[0] == 'list':
return getlist(x[1]) + [x[2]]
return [x]
def getfilter(exp, context):
f = getsymbol(exp)
if f not in context._filters:
raise error.ParseError(_("unknown function '%s'") % f)
return context._filters[f]
def gettemplate(exp, context):
if exp[0] == 'string':
return compiletemplate(exp[1], context)
if exp[0] == 'symbol':
return context._load(exp[1])
raise error.ParseError(_("expected template specifier"))
def runstring(context, mapping, data):
return data
def runsymbol(context, mapping, key):
v = mapping.get(key)
if v is None:
v = context._defaults.get(key, '')
if util.safehasattr(v, '__call__'):
return v(**mapping)
return v
def buildfilter(exp, context):
func, data = compileexp(exp[1], context)
filt = getfilter(exp[2], context)
return (runfilter, (func, data, filt))
def runfilter(context, mapping, data):
func, data, filt = data
return filt(func(context, mapping, data))
def buildmap(exp, context):
func, data = compileexp(exp[1], context)
ctmpl = gettemplate(exp[2], context)
return (runmap, (func, data, ctmpl))
def runmap(context, mapping, data):
func, data, ctmpl = data
d = func(context, mapping, data)
lm = mapping.copy()
for i in d:
if isinstance(i, dict):
lm.update(i)
for f, d in ctmpl:
yield f(context, lm, d)
else:
# v is not an iterable of dicts, this happen when 'key'
# has been fully expanded already and format is useless.
# If so, return the expanded value.
yield i
def buildfunc(exp, context):
n = getsymbol(exp[1])
args = [compileexp(x, context) for x in getlist(exp[2])]
if n in funcs:
f = funcs[n]
return (f, args)
if n in context._filters:
if len(args) != 1:
raise error.ParseError(_("filter %s expects one argument") % n)
f = context._filters[n]
return (runfilter, (args[0][0], args[0][1], f))
methods = {
"string": lambda e, c: (runstring, e[1]),
"symbol": lambda e, c: (runsymbol, e[1]),
"group": lambda e, c: compileexp(e[1], c),
# ".": buildmember,
"|": buildfilter,
"%": buildmap,
"func": buildfunc,
}
funcs = {
}
# template engine
path = ['templates', '../templates']
stringify = templatefilters.stringify
def _flatten(thing):
'''yield a single stream from a possibly nested set of iterators'''
if isinstance(thing, str):
yield thing
elif not util.safehasattr(thing, '__iter__'):
if thing is not None:
yield str(thing)
else:
for i in thing:
if isinstance(i, str):
yield i
elif not util.safehasattr(i, '__iter__'):
if i is not None:
yield str(i)
elif i is not None:
for j in _flatten(i):
yield j
def parsestring(s, quoted=True):
'''parse a string using simple c-like syntax.
string must be in quotes if quoted is True.'''
if quoted:
if len(s) < 2 or s[0] != s[-1]:
raise SyntaxError(_('unmatched quotes'))
return s[1:-1].decode('string_escape')
return s.decode('string_escape')
class engine(object):
'''template expansion engine.
template expansion works like this. a map file contains key=value
pairs. if value is quoted, it is treated as string. otherwise, it
is treated as name of template file.
templater is asked to expand a key in map. it looks up key, and
looks for strings like this: {foo}. it expands {foo} by looking up
foo in map, and substituting it. expansion is recursive: it stops
when there is no more {foo} to replace.
expansion also allows formatting and filtering.
format uses key to expand each item in list. syntax is
{key%format}.
filter uses function to transform value. syntax is
{key|filter1|filter2|...}.'''
def __init__(self, loader, filters={}, defaults={}):
self._loader = loader
self._filters = filters
self._defaults = defaults
self._cache = {}
def _load(self, t):
'''load, parse, and cache a template'''
if t not in self._cache:
self._cache[t] = compiletemplate(self._loader(t), self)
return self._cache[t]
def process(self, t, mapping):
'''Perform expansion. t is name of map element to expand.
mapping contains added elements for use during expansion. Is a
generator.'''
return _flatten(func(self, mapping, data) for func, data in
self._load(t))
engines = {'default': engine}
class templater(object):
def __init__(self, mapfile, filters={}, defaults={}, cache={},
minchunk=1024, maxchunk=65536):
'''set up template engine.
mapfile is name of file to read map definitions from.
filters is dict of functions. each transforms a value into another.
defaults is dict of default map definitions.'''
self.mapfile = mapfile or 'template'
self.cache = cache.copy()
self.map = {}
self.base = (mapfile and os.path.dirname(mapfile)) or ''
self.filters = templatefilters.filters.copy()
self.filters.update(filters)
self.defaults = defaults
self.minchunk, self.maxchunk = minchunk, maxchunk
self.ecache = {}
if not mapfile:
return
if not os.path.exists(mapfile):
raise util.Abort(_('style not found: %s') % mapfile)
conf = config.config()
conf.read(mapfile)
for key, val in conf[''].items():
if val[0] in "'\"":
try:
self.cache[key] = parsestring(val)
except SyntaxError, inst:
raise SyntaxError('%s: %s' %
(conf.source('', key), inst.args[0]))
else:
val = 'default', val
if ':' in val[1]:
val = val[1].split(':', 1)
self.map[key] = val[0], os.path.join(self.base, val[1])
def __contains__(self, key):
return key in self.cache or key in self.map
def load(self, t):
'''Get the template for the given template name. Use a local cache.'''
if not t in self.cache:
try:
self.cache[t] = util.readfile(self.map[t][1])
except KeyError, inst:
raise util.Abort(_('"%s" not in template map') % inst.args[0])
except IOError, inst:
raise IOError(inst.args[0], _('template file %s: %s') %
(self.map[t][1], inst.args[1]))
return self.cache[t]
def __call__(self, t, **mapping):
ttype = t in self.map and self.map[t][0] or 'default'
if ttype not in self.ecache:
self.ecache[ttype] = engines[ttype](self.load,
self.filters, self.defaults)
proc = self.ecache[ttype]
stream = proc.process(t, mapping)
if self.minchunk:
stream = util.increasingchunks(stream, min=self.minchunk,
max=self.maxchunk)
return stream
def templatepath(name=None):
'''return location of template file or directory (if no name).
returns None if not found.'''
normpaths = []
# executable version (py2exe) doesn't support __file__
if util.mainfrozen():
module = sys.executable
else:
module = __file__
for f in path:
if f.startswith('/'):
p = f
else:
fl = f.split('/')
p = os.path.join(os.path.dirname(module), *fl)
if name:
p = os.path.join(p, name)
if name and os.path.exists(p):
return os.path.normpath(p)
elif os.path.isdir(p):
normpaths.append(os.path.normpath(p))
return normpaths
def stylemap(styles, paths=None):
"""Return path to mapfile for a given style.
Searches mapfile in the following locations:
1. templatepath/style/map
2. templatepath/map-style
3. templatepath/map
"""
if paths is None:
paths = templatepath()
elif isinstance(paths, str):
paths = [paths]
if isinstance(styles, str):
styles = [styles]
for style in styles:
if not style:
continue
locations = [os.path.join(style, 'map'), 'map-' + style]
locations.append('map')
for path in paths:
for location in locations:
mapfile = os.path.join(path, location)
if os.path.isfile(mapfile):
return style, mapfile
raise RuntimeError("No hgweb templates found in %r" % paths)