I find that the vast majority of vendor integrations and playbooks automations are 90% identical: ingest inbound data (array, object, etc), parse through it whilst validating and extracting, then finally pushing it out.
This means I use the same code aaaaaall the time. So I thought I would make a little cheatsheet for the basics (to prevent me googling the same things over and over). This list will change/grow over time.
Not covered in this cheatsheet:
- Local file handling (open, read, close, etc)
- HTTP and SSL request/replies
- Time/date handling
To keep formatting simple, “<<tab>>” respresents a real Tab in the code
| # | *** | *** |
| # | Common Lib Imports | |
| import json, re, pprint, time, random, base64 | ||
| # | Basic string | |
| myString = “hi” | ||
| myString += ” I added a bit” | ||
| # | Convert | |
| myNum = int(myString) | ||
| myInt = str(myNumber) | ||
| # | If | |
| if varA > 5: <<tab>>print(“High”) elif varA > 0: <<tab>>print(“Medium”) else: <<tab>>print(“Zero”) | Basic structure Remember indents are tabs | |
| if myString == “compare me”: | Simple string comparison | |
| if myVar is None: | None / Null | |
| if not myVar: | Check if value exists, but is empty | |
| if (a == b) and (not b == c): | ||
| if (a < 5 < b): | If both are true | |
| if isinstance(myVar, list): | list, dict, str, int… etc | |
| # | Lists (arrays) | |
| myList = [] | ||
| myList.append(“bob”) | ||
| [output1, output2] = myList.split(‘character’) | ||
| myList = myString.split(” “) | ||
| myString = “-“.join(myList) | ||
| # | Python Dict | |
| myDict = {} | alternative >> myDict = dict() | |
| myVar = myDict.get(“key”, default_value) | Extract a value into another var | |
| myVar = myObject[‘key’] | Similar to above, but will return error if not found | |
| myDict[‘key’] = ‘value’ | Set a new value to the Dict | |
| if myKey in myDict: | Check if key exists | |
| myList = myDict.keys() | Same for “.values()” | |
my_dict.pop('key', None) | Safe is key exists or not | |
del my_dict['key'] | errors if key doesn’t exist | |
| # | Json | (Technically not a Dict, but handled very similarly) |
| import json | Import to code to use the calls | |
| myJson = {} | ||
| myJson = json.loads(string) | Where string is in the form “{‘key’:value}” | |
| myStr = json.dumps(string) | ||
| myString = myJson[‘key’] | ||
| myJson[‘key’] = newValue | ||
| myJsonAsString = json.dumps(myJson) | ||
| if myKey in myJson: | ||
| # | Loops | |
| for value in myList: <<tab>>print(value) | Loop a List | |
| while condition == True: | Simple while | |
| for myInt in range(5): | myInt will be 1,2,3,4,5 | |
| for index in range(len(myList)): | index will represent a number of the position in array | |
| for key, value in myJson.items(): | Loop through Json/Dict | |
| for key in jsonObject: <<tab>>value = jsonObject[key] | Alternative to the above | |
| break | Break out of the current loop (1 layer) to next code | |
| continue | Stop processing this loop, and go to next iteration of this loop structure | |
| # | Regex | |
| newString = re.sub(r”pattern”, “replaceWith”, targetString)) | regex substitution | |
| arrayResults = re.findall(r’pattern’, targetString) | regex findall | |
| matches = re.match(r”Goodbye”, “Hello”) if match is None: | regex match and test | |
| objectResults = re.search(“[a-z]+”,myVar) | Returns complex output | |
| # | base64 | |
| encoded = base64.b64encode(‘Hello World’) | Encode a string into Base64 | |
| readableData = base64.b64decode(encoded) | Convert Base64 back into the original string | |
| # | Try | |
| try: <<tab>>print(nonExistentVariable) except: <<tab>>print(“Something went wrong”) finally: <<tab>>print(“The ‘try except’ is finished”) | Remember tab indents | |
| # | Debug | |
| print() | Simple print | |
| pprint() | Print more complicated objects from pprint import pprint | |
| # | Bits and Bobs | |
| random.seed() myInt = random.random() | Int between 0.0 and 1.0 | |
| randomInt = random.randint(1,100) | Int between x and y | |
| time.sleep(1) | ||
print(type(x)) | To get the Type of a variable |
Nice!