#!/usr/bin/python # # Copyright (C) 2011, 2012, 2013 Google Inc. # # 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. """Script for converting Python constants to Haskell code fragments. """ import re import types from ganeti import _autoconf from ganeti import compat from ganeti import constants from ganeti import errors from ganeti import luxi from ganeti import qlang from ganeti import jstore #: Constant name regex CONSTANT_RE = re.compile("^[A-Z][A-Z0-9_-]+$") #: Private name regex PRIVATE_RE = re.compile("^__.+__$") #: The type of regex objects RE_TYPE = type(CONSTANT_RE) #: Keys which do not declare a value (manually maintained). By adding # values here, we can make more lists use the actual names; otherwise # we'll have (e.g.) both DEFAULT_ENABLED_HYPERVISOR and HT_XEN_PVM # declare the same value, and thus the list of valid hypervisors will # have strings instead of easily looked-up names. IGNORED_DECL_NAMES = ["DEFAULT_ENABLED_HYPERVISOR"] def NameRules(name): """Converts the upper-cased Python name to Haskell camelCase. """ name = name.replace("-", "_") elems = name.split("_") return elems[0].lower() + "".join(e.capitalize() for e in elems[1:]) def StringValueRules(value): """Converts a string value from Python to Haskell. """ value = value.encode("string_escape") # escapes backslashes value = value.replace("\"", "\\\"") return value def DictKeyName(dict_name, key_name): """Converts a dict plus key name to a full name. """ return"%s_%s" % (dict_name, str(key_name).upper()) def HaskellTypeVal(value): """Returns the Haskell type and value for a Python value. Note that this only work for 'plain' Python types. @returns: (string, string) or None, if we can't determine the type. """ if isinstance(value, basestring): return ("String", "\"%s\"" % StringValueRules(value)) elif isinstance(value, bool): return ("Bool", "%s" % value) elif isinstance(value, int): return ("Int", "%d" % value) elif isinstance(value, long): return ("Integer", "%d" % value) elif isinstance(value, float): return ("Double", "%f" % value) else: return None def IdentifyOrigin(all_items, value): """Tries to identify a constant name from a constant's value. This uses a simple algorithm: is there a constant (and only one) with the same value? If so, then it returns that constants' name. @note: it is recommended to use this only for tuples/lists/sets, and not for individual (top-level) values @param all_items: a dictionary of name/values for the current module @param value: the value for which we try to find an origin """ found = [name for (name, v) in all_items.items() if v is value and name not in IGNORED_DECL_NAMES] if len(found) == 1: return found[0] else: return None def FormatListElems(all_items, pfx_name, ovals, tvals): """Formats a list's elements. This formats the elements as either values or, if we find all origins, as names. @param all_items: a dictionary of name/values for the current module @param pfx_name: the prefix name currently used @param ovals: the list of actual (Python) values @param tvals: the list of values we want to format in the Haskell form """ origins = [IdentifyOrigin(all_items, v) for v in ovals] if compat.all(x is not None for x in origins): values = [NameRules(pfx_name + origin) for origin in origins] else: values = tvals return ", ".join(values) def FormatDict(all_items, pfx_name, py_name, hs_name, mydict): """Converts a dictionary to a Haskell association list ([(k, v)]), if possible. @param all_items: a dictionary of name/values for the current module @param pfx_name: the prefix name currently used @param py_name: the Python name @param hs_name: the Haskell name @param mydict: a dictonary, unknown yet if homogenous or not """ # need this for ordering orig_list = mydict.items() list_form = [(HaskellTypeVal(k), HaskellTypeVal(v)) for k, v in orig_list] if compat.any(v is None or k is None for k, v in list_form): # type not known return [] all_keys = [k for k, _ in list_form] all_vals = [v for _, v in list_form] key_types = set(k[0] for k in all_keys) val_types = set(v[0] for v in all_vals) if not(len(key_types) == 1 and len(val_types) == 1): # multiple types return [] # record the key and value Haskell types key_type = key_types.pop() val_type = val_types.pop() # now try to find names for the keys, instead of raw values key_origins = [IdentifyOrigin(all_items, k) for k, _ in orig_list] if compat.all(x is not None for x in key_origins): key_v = [NameRules(pfx_name + origin) for origin in key_origins] else: key_v = [k[1] for k in all_keys] # ... and for values val_origins = [IdentifyOrigin(all_items, v) for _, v in orig_list] if compat.all(x is not None for x in val_origins): val_v = [NameRules(pfx_name + origin) for origin in val_origins] else: val_v = [v[1] for v in all_vals] # finally generate the output kv_pairs = ["(%s, %s)" % (k, v) for k, v in zip(key_v, val_v)] return ["-- | Converted from Python dictionary @%s@" % py_name, "%s :: [(%s, %s)]" % (hs_name, key_type, val_type), "%s = [%s]" % (hs_name, ", ".join(kv_pairs)), ] def ConvertVariable(prefix, name, value, all_items): """Converts a given variable to Haskell code. @param prefix: a prefix for the Haskell name (useful for module identification) @param name: the Python name @param value: the value @param all_items: a dictionary of name/value for the module being processed @return: a list of Haskell code lines """ lines = [] if prefix: pfx_name = prefix + "_" fqn = prefix + "." + name else: pfx_name = "" fqn = name hs_name = NameRules(pfx_name + name) hs_typeval = HaskellTypeVal(value) if (isinstance(value, types.ModuleType) or callable(value) or PRIVATE_RE.match(name)): # no sense in marking these, as we don't _want_ to convert them; the # message in the next if block is for datatypes we don't _know_ # (yet) how to convert pass elif not CONSTANT_RE.match(name): lines.append("-- Skipped %s %s, not constant" % (fqn, type(value))) elif hs_typeval is not None: # this is a simple value (hs_type, hs_val) = hs_typeval lines.append("-- | Converted from Python constant @%s@" % fqn) lines.append("%s :: %s" % (hs_name, hs_type)) lines.append("%s = %s" % (hs_name, hs_val)) elif isinstance(value, dict): if value: lines.append("-- Following lines come from dictionary %s" % fqn) # try to build a real map here, if all keys have same type, and # all values too (i.e. we have a homogeneous dictionary) lines.extend(FormatDict(all_items, pfx_name, fqn, hs_name, value)) # and now create individual names for k in sorted(value.keys()): lines.extend(ConvertVariable(prefix, DictKeyName(name, k), value[k], all_items)) elif isinstance(value, tuple): tvs = [HaskellTypeVal(elem) for elem in value] # Custom rule for special cluster verify error tuples if name.startswith("CV_E") and len(value) == 3 and tvs[1][0] is not None: cv_ename = hs_name + "Code" lines.append("-- | Special cluster verify code %s" % name) lines.append("%s :: %s" % (cv_ename, tvs[1][0])) lines.append("%s = %s" % (cv_ename, tvs[1][1])) lines.append("") if compat.all(e is not None for e in tvs): ttypes = ", ".join(e[0] for e in tvs) tvals = FormatListElems(all_items, pfx_name, value, [e[1] for e in tvs]) lines.append("-- | Converted from Python tuple @%s@" % fqn) lines.append("%s :: (%s)" % (hs_name, ttypes)) lines.append("%s = (%s)" % (hs_name, tvals)) else: lines.append("-- Skipped tuple %s, cannot convert all elements" % fqn) elif isinstance(value, (list, set, frozenset)): # Lists and frozensets are handled the same in Haskell: as lists, # since lists are immutable and we don't need for constants the # high-speed of an actual Set type. However, we can only convert # them if they have the same type for all elements (which is a # normal expectation for constants, our code should be well # behaved); note that this is different from the tuples case, # where we always (for some values of always) can convert tvs = [HaskellTypeVal(elem) for elem in value] if compat.all(e is not None for e in tvs): ttypes, tvals = zip(*tvs) uniq_types = set(ttypes) if len(uniq_types) == 1: values = FormatListElems(all_items, pfx_name, value, tvals) lines.append("-- | Converted from Python list or set @%s@" % fqn) lines.append("%s :: [%s]" % (hs_name, uniq_types.pop())) lines.append("%s = [%s]" % (hs_name, values)) else: lines.append("-- | Skipped list/set %s, is not homogeneous" % fqn) else: lines.append("-- | Skipped list/set %s, cannot convert all elems" % fqn) elif isinstance(value, RE_TYPE): tvs = HaskellTypeVal(value.pattern) assert tvs is not None lines.append("-- | Converted from Python RE object @%s@" % fqn) lines.append("%s :: %s" % (hs_name, tvs[0])) lines.append("%s = %s" % (hs_name, tvs[1])) else: lines.append("-- Skipped %s, %s not handled" % (fqn, type(value))) return lines def Convert(module, prefix): """Converts the constants to Haskell. """ lines = [""] all_items = dict((name, getattr(module, name)) for name in dir(module)) for name in sorted(all_items.keys()): value = all_items[name] new_lines = ConvertVariable(prefix, name, value, all_items) if new_lines: lines.extend(new_lines) lines.append("") return "\n".join(lines) def main(): print Convert(constants, "") print Convert(luxi, "luxi") print Convert(qlang, "qlang") print Convert(_autoconf, "autoconf") print Convert(errors, "errors") print Convert(jstore, "jstore") if __name__ == "__main__": main()