Source code for pydm.utilities.macro

import io
import six
from string import Template
import json

# Macro parsing states
PRE_NAME = 0
IN_NAME = 1
PRE_VAL = 2
IN_VAL = 3


[docs]def substitute_in_file(file_path, macros): """ Substitute the macros given by ${name} at the given file with the entries on the `macros` dictionary. Parameters ---------- file_path : str The path to the file in which to substitute macros : dict Dictionary containing macro name as key and value as what will be substituted. Returns ------- file : io.StringIO File-like object with the proper substitutions. """ template = template_for_file(file_path) return replace_macros_in_template(template, macros)
def replace_macros_in_template(template, macros): curr_template = template prev_template = Template("") expanded_text = "" for i in range(100): expanded_text = curr_template.safe_substitute(macros) if curr_template.template == prev_template.template: break prev_template = curr_template curr_template = Template(expanded_text) return io.StringIO(six.text_type(expanded_text)) def template_for_file(file_path): with open(file_path) as orig_file: text = Template(orig_file.read()) return text
[docs]def parse_macro_string(macro_string): """Parses a macro string and returns a dictionary. First, this method attempts to parse the string as JSON. If that fails, it attempts to parse it as an EPICS-style macro string. The parsing algorithm for that case is very closely based on macParseDefns in libCom/macUtil.c""" if not macro_string: return {} macro_string = str(macro_string) try: macros = json.loads(macro_string) return macros except ValueError: if "=" not in macro_string: raise ValueError("Could not parse macro argument as JSON.") macros = {} state = PRE_NAME quote = None name_start = None name_end = None val_start = None val_end = None for (i,c) in enumerate(macro_string): if quote: if c == quote: quote = False elif c == "'" or c == '"': quote = c continue escape = macro_string[i-1] == "\\" if state == PRE_NAME: if (not quote) and (not escape) and (c.isspace() or c == ","): continue name_start = i state = IN_NAME elif state == IN_NAME: if quote or escape: continue if c == "=" or c == ",": name_end = i state = PRE_VAL elif state == PRE_VAL: if (not quote) and (not escape) and c.isspace(): continue val_start = i state = IN_VAL if i == len(macro_string)-1: val_end = i+1 elif state == IN_VAL: if quote or escape: continue if c == ",": val_end = i state = PRE_NAME elif i == len(macro_string)-1: val_end = i+1 state = PRE_NAME else: continue if not (None in (name_start, name_end, val_start, val_end)): key = macro_string[name_start:name_end].strip().replace("\\", "") val = macro_string[val_start:val_end].strip('"\'').replace("\\", "") macros[key] = val name_start = None name_end = None val_start = None val_end = None state = PRE_NAME return macros