From 20fb08f202d0cd47232d3aef3e7dae095cc7322a Mon Sep 17 00:00:00 2001
From: Ceda EI <ceda_ei@webionite.com>
Date: Mon, 30 Dec 2019 22:13:10 +0530
Subject: [PATCH] Add gINIe parser.

---
 .gitignore |   3 ++
 ginie.py   | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 138 insertions(+)
 create mode 100644 .gitignore
 create mode 100755 ginie.py

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..329efad
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+__pycache__/
+*.pyc
+config.gie
diff --git a/ginie.py b/ginie.py
new file mode 100755
index 0000000..6cff476
--- /dev/null
+++ b/ginie.py
@@ -0,0 +1,135 @@
+#!/usr/bin/env python3
+"gINIe Parser for Wish"
+
+import re
+import sys
+
+
+class GinieParseError(ValueError):
+    "Exception Class for errors in"
+
+
+def loads(string):
+    """
+    Deserialize `string` (a `str` instance containing a gINIe document)
+    into a Python list.
+
+    Return Value: List of `block` and `section` dicts
+
+    `block` dicts are of form
+    {
+        'type': 'block',
+        'name': 'name_of_block_as_in_config',
+        'config': {}
+    }
+    where `name` and `config` keys are based on the gINIe document.
+
+    `section` dicts are of form
+
+    {
+        'type': 'block',
+        'name': 'name_of_block_as_in_config',
+        'blocks': []
+    }
+    where `name` and `blocks` keys are based on the gINIe document and blocks
+    is a list of block dicts found in the section.
+    """
+    config = []
+    section_re = re.compile(r"^\|(?P<section>.+)\|$")
+    block_re = re.compile(r"^\[(?P<block>[^\]]*)\]$")
+    line_re = re.compile(r"^\s*(?P<key>[^\s=]+)(\s*)=\s*?(?P<value>.*)$")
+    empty_re = re.compile(r"^\s*$")
+    comment_re = re.compile(r"^\s*(#|;)")
+    current_block = None
+    current_section = None
+    for idx, line in enumerate(string.splitlines()):
+        idx += 1  # Since line numbers begin with 1
+        # Skip comments and empty lines
+        if empty_re.match(line) or comment_re.match(line):
+            continue
+
+        # Section parsing
+        if line.startswith("|"):
+            match = section_re.match(line)
+            if match is None:
+                err = "Invalid line {}".format(idx)
+                raise GinieParseError(err)
+            current_section = {
+                "type": "section",
+                "name": match.group("section"),
+                "blocks": []
+            }
+            config.append(current_section)
+            continue
+
+        # Block Parsing
+        if line.startswith("["):
+            match = block_re.match(line)
+            if match is None:
+                err = "Invalid block name on line {}".format(idx)
+                raise GinieParseError(err)
+            current_block = {
+                "type": "block",
+                "name": match.group("block"),
+                "config": {}
+            }
+            if current_section is None:
+                config.append(current_block)
+            else:
+                current_section["blocks"].append(current_block)
+            continue
+
+        # If it is neither a comment, nor a section, nor a block, it has to be
+        # a key, value pair.
+        if current_block is None:
+            raise GinieParseError("Found lines outside a block")
+
+        match = line_re.match(line)
+        if match is None:
+            raise GinieParseError("Invalid line {}: {}".format(idx, line))
+
+        value = match.group('value').strip()
+        if value:
+            if value[0] == value[-1] == "'" or value[0] == value[-1] == '"':
+                value = value[1:-1]
+        current_block["config"][match.group('key').strip()] = value
+
+    return config
+
+
+def load(file):
+    """
+    Deserialize `file` (a file-like object containing a gINIe document)
+    into a Python list.
+
+    Return Value: List of `block` and `section` dicts
+
+    `block` dicts are of form
+    {
+        'type': 'block',
+        'name': 'name_of_block_as_in_config',
+        'config': {}
+    }
+    where `name` and `config` keys are based on the gINIe document.
+
+    `section` dicts are of form
+
+    {
+        'type': 'block',
+        'name': 'name_of_block_as_in_config',
+        'blocks': []
+    }
+    where `name` and `blocks` keys are based on the gINIe document and blocks
+    is a list of block dicts found in the section.
+    """
+    return loads(file.read())
+
+
+if __name__ == "__main__":
+    if len(sys.argv) == 1:
+        print("Usage: {} file.gie|-".format(sys.argv[0]))
+    elif sys.argv[1] == '-':
+        print(load(sys.stdin))
+    else:
+        with open(sys.argv[1]) as source:
+            print(load(source))