import json import re def pathSegmentParse(path): ''' Parses a ppath string into logical segments that can be applied individually. There are 2 kinds of segments, paths and filters. Paths indicate a path through the structure. Filters evaluate an array of substructures to only those that match ''' segments = [] parts = re.split('\[|\]',path) for part in parts: if not part: continue seg = {} if part[0]=='.': part = part[1:] if '=' in part: sub_parts = part.split('=') seg['path'] = sub_parts[0] seg['type'] = 'filter' seg['value'] = part.split('=')[1] else: seg['type'] = 'path' seg['path'] = part segments.append(seg) return segments def applyPath(segment,pointers): ''' Takes an array of pointers and a ppath segment and returns a new array of pointers that match the given path ''' path = segment['path'] parts = path.split('.') for part in parts: new_pointers = [] for i in range(0,len(pointers)): if isinstance(pointers[i], (dict,list)): #then we're not at a simple value if pointers[i].get(part): if isinstance(pointers[i][part], list): for p in pointers[i][part]: new_pointers.append(p) else: new_pointers.append(pointers[i][part]) pointers = new_pointers return pointers def applyFilter(segment,pointers): ''' Takes a filter segment of a ppath and applied it to each pointer and returns an array of pointers that resolve to the value given in the segment ''' new_pointers = [] for p in pointers: value = applyPath(segment,[p]) if value: if segment['value'] in value: new_pointers.append(p) return new_pointers def getFromPPath(data,path,default=[]): ''' Takes a python dict and a ppath string and finds the matching data in the dict. If no data can be found the default is returned ''' pointers = [data] segments = pathSegmentParse(path) for segment in segments: if segment['type'] == 'path': pointers = applyPath(segment,pointers) if segment['type'] == 'filter': pointers = applyFilter(segment,pointers) if len(pointers)==0: return default return pointers JSON = ''' { "friends" : [ {"first_name": "Wendell", "last_name": "Jordan", "phone":[{"type":"mobile","number":"440-123-8126"},{"type":"home","number":"440-890-5573"}],"gender":"male"}, {"first_name": "Jeanne", "last_name": "Morris", "phone":[{"type":"mobile","number":"216-123-0079"},{"type":"home","number":"216-890-7830"}],"gender":"female"}, {"first_name": "Herman", "last_name": "Mcdaniel", "phone":[{"type":"mobile","number":"440-123-1344"},{"type":"home","number":"440-890-8825"}],"gender":"male"}, {"first_name": "Emanuel", "last_name": "Becker", "phone":[{"type":"mobile","number":"216-123-8825"},{"type":"home","number":"216-890-8332"}],"gender":"female"}, {"first_name": "Sara", "last_name": "Todd", "phone":[{"type":"mobile","number":"216-123-6117"},{"type":"home","number":"216-890-2899"}],"gender":"female"}, {"first_name": "Victoria", "last_name": "Gray", "phone":[{"type":"mobile","number":"216-123-8456"},{"type":"home","number":"216-890-4469"}],"gender":"female"}, {"first_name": "Ronnie", "last_name": "Cook", "phone":[{"type":"mobile","number":"216-123-2006"},{"type":"home","number":"216-890-2006"}],"gender":"female"}, {"first_name": "Gilbert", "last_name": "Morton", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Claudia", "last_name": "Padilla", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Doris", "last_name": "Maxwell", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Luis", "last_name": "Stokes", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Byron", "last_name": "Kelley", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Terri", "last_name": "Hayes", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Flora", "last_name": "Greene", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Guadalupe", "last_name": "Strickland","phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Sylvia", "last_name": "Sutton", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Caroline", "last_name": "Perkins", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Sherri", "last_name": "Ross", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Lloyd", "last_name": "Townsend", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Cody", "last_name": "Erickson", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Ron", "last_name": "Williams", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Francis", "last_name": "Fitzgerald","phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Kenneth", "last_name": "Hopkins", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Mary", "last_name": "Ballard", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Andre", "last_name": "Lewis", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Marguerite", "last_name": "Medina", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Rachael", "last_name": "Brown", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Daryl", "last_name": "Mccarthy", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Shelia", "last_name": "Schultz", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Geoffrey", "last_name": "Mcdonald", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Tyler", "last_name": "Nichols", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Gretchen", "last_name": "Graves", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Lora", "last_name": "Pearson", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Katie", "last_name": "Watts", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Taylor", "last_name": "Jennings", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Pamela", "last_name": "Buchanan", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Mark", "last_name": "Potter", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Domingo", "last_name": "Allen", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Jean", "last_name": "Kim", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Monique", "last_name": "Sullivan", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Theresa", "last_name": "Beck", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Morris", "last_name": "Moreno", "phone":[ {"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Wade", "last_name": "Luna", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Traci", "last_name": "Garcia", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "Alan", "last_name": "Washington","phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Toni", "last_name": "Weaver", "phone":[{"type":"mobile","number":"216-123-4567"},{"type":"home","number":"216-890-4567"}],"gender":"female"}, {"first_name": "David", "last_name": "Brown", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Sergio", "last_name": "Marsh", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Charlie", "last_name": "Rice", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"}, {"first_name": "Bernard", "last_name": "Hogan", "phone":[{"type":"mobile","number":"440-123-4567"},{"type":"home","number":"440-890-4567"}],"gender":"male"} ] } ''' data = json.loads(JSON) # how many friends do I have? assert(len(getFromPPath(data,'friends'))==50) # how many friends with the last name brown? assert(len(getFromPPath(data,'friends[last_name=Brown]'))==2) # What are the first names of the friends whose last names are brown? assert(getFromPPath(data,'friends[last_name=Brown].first_name')[0]=="Rachael") assert(getFromPPath(data,'friends[last_name=Brown].first_name')[1]=="David") # what's the first name of the person with this phone number? assert(len(getFromPPath(data,"friends[phone.number=216-890-7830].first_name"))==1) assert(getFromPPath(data,"friends[phone.number=216-890-7830].first_name")[0]=="Jeanne") # what about this phone number? assert(len(getFromPPath(data,"friends[phone.number=216-123-0079].first_name"))==1) assert(getFromPPath(data,"friends[phone.number=216-123-0079].first_name")[0]=="Jeanne") # How many friends are female? assert(len(getFromPPath(data,"friends[gender=female]"))==28) # First names of female friends assert(len(getFromPPath(data,"friends[gender=female].first_name"))==28) assert(getFromPPath(data,"friends[gender=female].first_name")[0]=="Jeanne") assert(getFromPPath(data,"friends[gender=female].first_name")[10]=="Sylvia") assert(getFromPPath(data,"friends[gender=female].first_name")[27]=="Toni") # Phone numbers of female friends assert(len(getFromPPath(data,"friends[gender=female].phone.number"))==56) assert(getFromPPath(data,"friends[gender=female].phone.number")[0]=="216-123-0079") assert(getFromPPath(data,"friends[gender=female].phone.number")[10]=="216-123-4567") assert(getFromPPath(data,"friends[gender=female].phone.number")[55]=="216-890-4567") # Mobile phone numbers of female friends assert(len(getFromPPath(data,"friends[gender=female].phone[type=mobile].number"))==28) assert(getFromPPath(data,"friends[gender=female].phone[type=mobile].number")[0]=="216-123-0079") assert(getFromPPath(data,"friends[gender=female].phone[type=mobile].number")[10]=="216-123-4567") assert(getFromPPath(data,"friends[gender=female].phone[type=mobile].number")[27]=="216-123-4567") # Male friends assert(len(getFromPPath(data,"friends[gender=male]"))==22) # Male friends with mobile phones assert(len(getFromPPath(data,"friends[gender=male][phone.type=mobile]"))==21) # Male friends with home phones assert(len(getFromPPath(data,"friends[gender=male][phone.type=home]"))==22) # First names of male friends with home phones assert(getFromPPath(data,"friends[gender=male][phone.type=home].first_name")[0]=="Wendell") assert(getFromPPath(data,"friends[gender=male][phone.type=home].first_name")[10]=="Daryl") assert(getFromPPath(data,"friends[gender=male][phone.type=home].first_name")[21]=="Bernard") # Male friends with fax numbers assert(len(getFromPPath(data,"friends[gender=male][phone.type=fax]"))==0)