new streamlined parser

jc/parsers/asciitable_m.py

@@ -44,7 +44,7 @@ Examples:
     []
 """
 import re
-from typing import Iterable, List, Dict, Optional, Generator
+from typing import Iterable, Tuple, List, Dict
 import jc.utils
 from jc.exceptions import ParseError
 
@@ -73,11 +73,6 @@ def _process(proc_data: List[Dict]) -> List[Dict]:
 
         List of Dictionaries. Structured to conform to the schema.
     """
-    # remove newlines from values
-    # for item in proc_data:
-    #     for k, v in item.items():
-    #         item[k] = v.replace('\n', '')
-
     return proc_data
 
 
@@ -115,16 +110,9 @@ def _table_sniff(string: str) -> str:
     return 'simple'
 
 
-def _pretty_set_separators(table_lines: Iterable, separator: str) -> Generator[str, None, None]:
-    """Return a generator that yields rows standardized separators"""
-    for line in table_lines:
+def _is_separator(line: str) -> bool:
+    """Returns true if a table separator line is found"""
     strip_line = line.strip()
-
-        # skip any blanks
-        if not strip_line:
-            continue
-
-        # yield row separators as a sentinel string
     if   strip_line.startswith('╒═') and strip_line.endswith('═╕')\
         or strip_line.startswith('╞═') and strip_line.endswith('═╡')\
         or strip_line.startswith('╘═') and strip_line.endswith('═╛')\
@@ -133,61 +121,17 @@ def _pretty_set_separators(table_lines: Iterable, separator: str) -> Generator[s
         or strip_line.startswith('└─') and strip_line.endswith('─┘')\
         or strip_line.startswith('+=') and strip_line.endswith('=+')\
         or strip_line.startswith('+-') and strip_line.endswith('-+'):
-            yield separator
-            continue
-
-        # remove the table column separator characters and yield the line
-        # line = line.replace('|', ' ').replace('│', ' ')
-        yield line
+        return True
+    return False
 
 
-def _pretty_normalize_rows(table_lines: Iterable,
-                           separator: str,
-                           data_separator: str) -> Generator[str, None, None]:
-    """
-    Return a generator that yields header and data rows with different separators.
-    Also removes spaces from headers.
-    """
-    header_found = False
-    data_found = False
-
-    # Removes initial table lines, finds the header row(s) and separates
-    # the header from the data rows with different separator characters.
-    for i in table_lines:
-        if separator in i and not header_found and not data_found:
-            # top table frame
-            continue
-        if not separator in i and not header_found and not data_found:
-            header_found = True
-            # first header data found
-            # remove spaces from header
-            i = re.sub(r'\b \b', '_', i)
-            yield i
-            continue
-        if not separator in i and header_found and not data_found:
-            # subsequent header data found
-            # remove spaces from header
-            i = re.sub(r'\b \b', '_', i)
-            yield i
-            continue
-        if separator in i and header_found and not data_found:
-            data_found = True
-            # table separator found - this is a header separator
-            yield separator
-            continue
-        if not separator in i and header_found and data_found:
-            # subsequent data row found
-            yield i
-            continue
-        if separator in i and header_found and data_found:
-            # table separator found - this is a data separator
-            yield data_separator
-            continue
+def _snake_case(line: str) -> str:
+    """replace spaces between words with an underscores and set to lowercase"""
+    return re.sub(r'\b \b', '_', line).lower()
 
 
-def _pretty_table_parse(table: Iterable) -> List[Dict]:
-    temp_table = []
-    for line in table:
+def _fixup_separators(line: str) -> str:
+    """Normalize separators, and remove first and last separators"""
     # normalize separator
     line = line.replace('│', '|')
 
@@ -199,129 +143,158 @@ def _pretty_table_parse(table: Iterable) -> List[Dict]:
     if line[-1] == '|':
         line = line[::-1].replace('|', ' ', 1)[::-1]
 
-        temp_table.append([x.strip() for x in line.split('|')])
+    return line
+
+
+def _normalize_rows(table_lines: Iterable[str]) -> List[Tuple[int, List[str]]]:
+    """
+    Return a List of tuples of a row counters and data lines.
+    """
+    result = []
+    header_found = False
+    data_found = False
+    row_counter = 0
+
+    for line in table_lines:
+        # skip blank lines
+        if not line.strip():
+            continue
+
+        # skip top table frame
+        if _is_separator(line) and not header_found and not data_found:
+            continue
+
+        # first header row found
+        if not _is_separator(line) and not header_found and not data_found:
+            header_found = True
+            line = _snake_case(line)
+            line = _fixup_separators(line)
+            line_list =  line.split('|')
+            line_list = [x.strip() for x in line_list]
+            result.append((row_counter, line_list))
+            continue
+
+        # subsequent header row found
+        if not _is_separator(line) and header_found and not data_found:
+            line = _snake_case(line)
+            line = _fixup_separators(line)
+            line_list =  line.split('|')
+            line_list = [x.strip() for x in line_list]
+            result.append((row_counter, line_list))
+            continue
+
+        # table separator found - this is a header separator
+        if _is_separator(line) and header_found and not data_found:
+            data_found = True
+            row_counter += 1
+            continue
+
+        # subsequent data row found
+        if not _is_separator(line) and header_found and data_found:
+            line = _fixup_separators(line)
+            line_list =  line.split('|')
+            line_list = [x.strip() for x in line_list]
+            result.append((row_counter, line_list))
+            continue
+
+        # table separator found - this is a data separator
+        if _is_separator(line) and header_found and data_found:
+            row_counter += 1
+            continue
 
-    headers = temp_table[0]
-    raw_data = temp_table[1:]
-    result = [dict.fromkeys(headers, None)]
-    result.extend([dict(zip(headers, r)) for r in raw_data])
     return result
 
 
-def _pretty_remove_header_rows(table: List[Dict], sep: str, data_sep: str) -> List[Optional[Dict]]:
-    """return a table with only data rows."""
-    # create a new list of row objects with new key names
-    data_obj_list: List[Optional[Dict]] = []
-    sep_found = False
-    data_sep_found = False
-    for obj in table:
-        #skip to data
-        for v in obj.values():
-            if not sep_found and not str(v).strip() == sep:
-                continue
-            if not sep_found and str(v).strip() == sep:
-                sep_found = True
-                continue
-        # append data row objects or None for separators
-        if sep_found:
-            for k, v in obj.items():
-                if str(v).strip() == data_sep:
-                    data_sep_found = True
-                    break
-                else:
-                    data_sep_found = False
-            if data_sep_found:
-                data_obj_list.append(None)
-            else:
-                data_obj_list.append(obj)
-
-    # remove first item, which is a separator
-    return data_obj_list[1:]
-
-
-def _pretty_map_new_keynames(table: List[Dict], sep: str) -> Dict:
+def _get_headers(table: Iterable[Tuple[int, List]]) -> List[List[str]]:
     """
-    returns a dict of old keyname to new keyname mappings by consolidating
-    multiline keynames from the input list of dictionaries.
+    return a list of all of the header rows (which are lists of strings.
+        [                            # headers
+            ['str', 'str', 'str'],   # header rows
+            ['str', 'str', 'str']
+        ]
     """
-    # first get all header objects to find full keynames. Stop when data rows are found.
-    header_obj_list = []
-    sep_found = False
-    for obj in table:
-        for v in obj.values():
-            if str(v).strip() == sep:
-                sep_found = True
-                break
-        if sep_found:
-            break
-        header_obj_list.append(obj)
-
-    if not header_obj_list:
-        header_obj_list = [{key: None for key in table[0]}]
-
-    # create an old-key to new-key name mapping dict
-    new_keynames_dict = dict.fromkeys([key for key in header_obj_list[0]], '')
-    for item in new_keynames_dict:
-        new_keynames_dict[item] = item
-    for obj in header_obj_list:
-        for k, v in obj.items():
-            if v:
-                new_keynames_dict[k] = new_keynames_dict[k] + '_' + v
-
-    # normalize keynames so they are lowercase, no spaces, and no redundat '_'s
-    for k, v in new_keynames_dict.items():
-        new_keynames_dict[k] = v.replace(' ', '_').lower()
-        new_keynames_dict[k] = re.sub(r'__+', '_', v)
-
-    return new_keynames_dict
+    result = []
+    for row_num, line in table:
+        if row_num == 0:
+            result.append(line)
+    return result
 
 
-def _pretty_rename_keys(table: List, new_keynames: Dict) -> List[Optional[Dict]]:
-    """rename all of the keys in the table based on the new_keynames mapping"""
-    renamed_key_table: List[Optional[Dict]] = []
-    for item in table:
-        if item:
-            renamed_key_table.append({new_keynames[k]:v for k, v in item.items()})
+def _get_data(table: Iterable[Tuple[int, List]]) -> List[List[List[str]]]:
+    """
+    return a list of rows, which are lists made up of lists of strings:
+        [                                # data
+            [                            # rows
+                ['str', 'str', 'str']    # lines
+            ]
+        ]
+    """
+    result: List[List[List[str]]] = []
+    current_row = 1
+    this_line: List[List[str]] = []
+    for row_num, line in table:
+        if row_num != 0:
+            if row_num != current_row:
+                result.append(this_line)
+                current_row = row_num
+                this_line = []
+
+            this_line.append(line)
+
+    if this_line:
+        result.append(this_line)
+
+    return result
+
+
+def _collapse_headers(table: List[List[str]]) -> List[str]:
+    """append each column string to return the full header list"""
+    result = table[0]
+    for line in table[1:]:
+        new_line: List[str] = []
+        for i, header in enumerate(line):
+            if header:
+                new_header = result[i] + '_' + header
+                new_header = re.sub(r'__+', '_', new_header)
+                new_line.append(new_header)
             else:
-            renamed_key_table.append(None)
+                new_line.append(result[i])
+        result = new_line
 
-    return renamed_key_table
+    return result
 
 
-def _pretty_consolidate_rows(table: List) -> List[Dict]:
-    """go through all data objects and combine values between data separators"""
-    consolidated_rows = []
-    current_obj = dict.fromkeys([key for key in table[0]], '')
-    for item in table:
-        if not item:
-            consolidated_rows.append(current_obj)
-            current_obj = dict.fromkeys([key for key in table[0]], '')
-            continue
+def _collapse_data(table: List[List[List[str]]]) -> List[List[str]]:
+    """combine data rows to return a simple list of lists"""
+    result: List[List[str]] = []
+
+    for row in table:
+        new_row: List[str] = []
+        for line in row:
+            if new_row:
+                for i, item in enumerate(line):
+                    new_row[i] = (new_row[i] + '\n' + item).strip()
             else:
-            for k, v in item.items():
-                if v:
-                    if not current_obj[k]:
-                        current_obj[k] = v
-                    else:
-                        current_obj[k] = current_obj[k] + '\n' + v
+                new_row = line
 
-    return consolidated_rows
+        result.append(new_row)
+
+    return result
+
+
+def _create_table_dict(header: List[str], data: List[List[str]]) -> List[Dict[str, str]]:
+    return [dict(zip(header, r)) for r in data]
 
 
 def _parse_pretty(string: str) -> List:
-    string_lines = string.splitlines()
-    sep = '~~~'
-    data_sep = '==='
-    separator = '  ' + sep + ' '
-    data_separator = '  ' + data_sep + ' '
+    string_lines: List[str] = string.splitlines()
+    clean: List[Tuple[int, List[str]]] = _normalize_rows(string_lines)
+    raw_headers: List[List[str]] = _get_headers(clean)
+    raw_data: List[List[List[str]]] = _get_data(clean)
 
-    clean: Generator = _pretty_set_separators(string_lines, separator)
-    normalized: Generator = _pretty_normalize_rows(clean, separator, data_separator)
-    raw_table: List[Dict] = _pretty_table_parse(normalized)  # was sparse_table_parse()
-    new_keynames: Dict = _pretty_map_new_keynames(raw_table, sep)
-    data_table: List[Optional[Dict]] = _pretty_remove_header_rows(raw_table, sep, data_sep)
-    table_with_renamed_keys: List[Optional[Dict]] = _pretty_rename_keys(data_table, new_keynames)
-    final_table: List[Dict] = _pretty_consolidate_rows(table_with_renamed_keys)
+    new_headers: List[str] = _collapse_headers(raw_headers)
+    new_data: List[List[str]] = _collapse_data(raw_data)
+    final_table: List[Dict[str, str]] = _create_table_dict(new_headers, new_data)
 
     return final_table