Regular Expressions 101

Community Patterns

0

Graphql parser for pretty printing

Created·2022-10-29 15:30
Flavor·Python
Parse Graphql queries Changelog (versions): Initial Version 2 is much improved and intended to integrate well with customized highlighting with the help of the awesome Rich library. Bug fixes and added rich example. Bugfixes and now the regex is actually recognizing the different parts of field_with_params. And an improved example to go with that. Todo (maybe): Improve the beginning, opening, closing and ending curly bracket recognition with better support for malformed queries and make sure there's only one BEGIN and one END in situations where newlines are present. Also differentiate between arbitrary text and actual graphql query language content. For example, the string "asdf" is currently recognized and categorized as a child_field when it shouldn't be recognized at all. Version 4 def pretty_query(query_string: str) -> str: import re from rich.console import Console from rich.highlighter import JSONHighlighter from rich.theme import Theme, DEFAULT_STYLES this is a string, not a tuple field_with_params_rgx = ( r'(?P+' # fields with parameters r'(?P\()' # opening parenthesis r'(?P\w+)\s?' # keywords and colons r'(?P\:)\s?' # keywords and colons r'(?P' # parameter values r'(?P\[?).+?' # opening square bracket r'(?P\]?))\s?' # closing square bracket r'(?P\)))' # closing parenthesis ) regexes = [ field_with_params_rgx, r'(?P^\{)|(?P\{)|(?P\}$)|(?P\})', # curly brackets r'(?P(?P\.{3})\s*?(?Pon)\s+?(?P\w+))', # fragments r'(?P(?!(?P=field_with_params)|(?P=fragment))\w+)(?=\s*?\{)', # parent fields r'(?P(?!(?P=field_with_params)|(?P=fragment))\w+)', # child fields ] indent = 2 count = 0 parts = [] for x in re.finditer('|'.join(rgx for rgx in regexes), query_string): data = x.groupdict() string = '' BEGIN = data['BEGIN'] open = data['open'] parent_field = data['field_with_params'] or data['parent_field'] child_field = data['child_field'] fragment = data['fragment'] close = data['close'] END = data['END'] if BEGIN: string += BEGIN count += indent if open: count += indent continue if parent_field: string += '{0: >{fill}}{value} {{'.format(' ', value=parent_field, fill=count) if child_field: string += '{0: >{fill}}{value}'.format(' ', value=child_field, fill=count) if fragment: string += '{0: >{fill}}{value} {{'.format(' ', value=fragment, fill=count) if close: count -= indent string += '{0: >{fill}}{value}'.format(' ', value=close, fill=count) if END: string += END count -= indent parts.append(string) class GQLHighlighter(JSONHighlighter): base_style = "gql." highlights = ['|'.join(rgx for rgx in regexes)] + JSONHighlighter.highlights theme = Theme({ **{ f'gql.{k}': DEFAULT_STYLES[f'json.{k}'] for k in ['brace', 'bool_true', 'bool_false', 'null', 'number', 'str', 'key'] }, 'gql.BEGIN': 'bold green', 'gql.END': 'bold green', 'gql.open': 'bold yellow', 'gql.close': 'bold blue', 'gql.field_with_params': 'bold blue', 'gql.parent_field': 'bold white', 'gql.child_field': 'italic green', 'gql.fragment': 'bold yellow', 'gql.dots': 'bold white', 'gql.on': 'green', 'gql.frag_field': 'bold magenta italic', 'gql.parenth_open': 'blue', 'gql.parenth_close': 'green', 'gql.keyword': 'yellow', 'gql.colon': 'blue', 'gql.list_open': 'bold yellow', 'gql.list_close': 'bold yellow', 'gql.value': 'cyan', }) console = Console(highlighter=GQLHighlighter(), theme=theme) console.print('\n'.join(parts)) return '\n'.join(parts)
Submitted by iwconfig

Community Library Entry

0

Regular Expression
Created·2022-08-13 02:27
Updated·2022-08-13 04:21
Flavor·PCRE2 (PHP)

/
^([A-Z](([A-Z]{1,2}[a-z0-9]+)+([A-Z]{1,3}[a-z0-9]+)*[A-Z]{0,3}|([a-z0-9]+[A-Z]{0,3})*|[A-Z]{1,2}))$|^([a-z][a-z0-9]*(([A-Z]{1,3}[a-z0-9]+)*[A-Z]{0,3}|([a-z0-9]+[A-Z]{1,3})*|[A-Z]{1,3}))$
/
gm
Open regex in editor

Description

PasCamelCase

A combination of pascal and camel case. PasCamelCase is a lenient case style that is allows a phrase to use either pascal case or camel case rules.

In addition, PasCamelCase allows for 2-3 letter acronyms such as IOStream, StreamIO, DeviceID, deviceID, AwsVPC, awsVPC, ```serialNO``. This rule is inspired by Microsoft's Capitalization Convention

Rules

For a phrase to be valid PasCamelCase it:

  • MUST start with a lower or upper case alphabet (a through z or A through Z)
  • MUST have no spaces, punctuation or special characters
  • MAY contain digits 0 - 9
  • CAN have at most 3 uppercase alphabets in a row
  • CAN end in an uppercase alphabet

The following are all valid PasCamelCase phrases:

  • a
  • aG
  • camelCase
  • camelCasE
  • aGa
  • alphabet
  • camelCase
  • cP3
  • a1
  • a1G
  • a123
  • camelCa1
  • camel01C
  • streamIO
  • deviceID
  • serialNO
  • awsVPC
  • A
  • Ag
  • AaA
  • Aabc123
  • Pascal2Case
  • Pascal2CaseA
  • Mode2A
  • Mode2A2
  • Mode2A2A
  • SupportsIpv6OnIos
  • IOStream
  • StreamIO
  • IOStream
  • DeviceID
  • AwsVPC
  • DeviceSNS
  • CreateAMode
  • CreateBMode
  • ABCabcABCabc
  • ABCabcABCabcA
  • Camel01CC01

The following are not PasCamelCase phrases:

  • 2PascalCase
  • CamelCa_1
  • HELLO
  • HTMLParser
  • AabcABCDabcABCD
  • streamIOIO
Submitted by anonymous