I am having trouble doing any single or batch query with boto 2.9.5 using the DynamoDB2 API
I need to do a batch query like this:
one_org = Table('[table-name]').batch_get(keys=[
{'key': '[user-id-hash]'},
{'key': '[user-id-hash]'},
{'key': '[user-id-hash]'},
{'key': '[user-id-hash]'},
])
for user in one_org:
for key, value in user.items():
print key, value
I keep getting this exception:
boto.dynamodb2.exceptions.ValidationException: ValidationException: 400 Bad Request
{
u'message': u'The provided key element does not match the schema',
u'__type': u'com.amazon.coral.validate#ValidationException'
}
Given this message I'd think there'd be a problem with the name of the key, but our key is called key, so it doesn't make any sense to me.
I included the stack trace below:
Traceback (most recent call last):
File "aws/interfaces.py", line 38, in <module>
for user in one_org:
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/dynamodb2/results.py", line 59, in next
self.fetch_more()
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/dynamodb2/results.py", line 141, in fetch_more
results = self.the_callable(*args, **kwargs)
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/dynamodb2/table.py", line 949, in _batch_get
raw_results = self.connection.batch_get_item(request_items=items)
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/dynamodb2/layer1.py", line 152, in batch_get_item
body=json.dumps(params))
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/dynamodb2/layer1.py", line 1479, in make_request
retry_handler=self._retry_handler)
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/connection.py", line 852, in _mexe
status = retry_handler(response, i, next_sleep)
File "/home/kasper/Falcon/thenest/venv/local/lib/python2.7/site-packages/boto/dynamodb2/layer1.py", line 1518, in _retry_handler
response.status, response.reason, data)
boto.dynamodb2.exceptions.ValidationException: ValidationException: 400 Bad Request
{u'message': u'The provided key element does not match the schema', u'__type': u'com.amazon.coral.validate#ValidationException'}
I was facing the same issue this morning. If you have defined a RangeKey in your schema then you need to specify that as well. If you don't want to specify the RangeKey and only get the item using HashKey then consider removing the RangeKey.
The error is saying that the value(s) provided do not match the type defined in the schema. I don't know what your schema is but, as an example, if the schema defined the primary key (called key in your case) as a string and you provided an integer value or vice-versa you would get this error.
Check your schema and make sure you are passing in the right type of value for your query.
Related
I've been trying to download a certain data on my graph and it returns this error :
Neo.ClientError.Statement.SyntaxError: Type mismatch: expected List<Node> but was Node (line 2, column 27 (offset: 77))"CALL apoc.export.csv.data(c,[], "contrib.csv",{})"
This is the query I did :
MATCH (c:Contrib) WHERE c.nationality CONTAINS "|" CALL apoc.export.csv.data(c,[], "contrib.csv",{}) YIELD file, source, format, nodes, relationships, properties, time, rows, batchSize, batches, done, data RETURN file, source, format, nodes, relationships, properties, time, rows, batchSize, batches, done, data
What went wrong ? :(
Thanks
The syntax for the function: apoc.export.csv.data is
apoc.export.csv.data(nodes,rels,file,config)
exports given nodes and relationships as csv to the provided file
The nodes is a collection of nodes rather than a node.
OLD: MATCH (c:Contrib) WHERE c.nationality CONTAINS "|"
CALL apoc.export.csv.data(c,[], "contrib.csv",{})
NEW: MATCH (c:Contrib) WHERE c.nationality CONTAINS "|"
WITH collect(c) as contribs
CALL apoc.export.csv.data(contribs, [], "contrib.csv", {})
I am trying to extract json file data using python but running in some errors.
aircraft.json (json file):
{ "now" : 1609298440.3,
"messages" : 31501,
"aircraft" : [
{"hex":"abadf9","alt_baro":37000,"alt_geom":36625,"gs":541.9,"track":73.3,"baro_rate":0,"version":0,"nac_p":7,"nac_v":1,"sil":2,"sil_type":"unknown","mlat":[],"tisb":[],"messages":13,"seen":6.6,"rssi":-25.3},
{"hex":"acc02b","flight":"SWA312 ","alt_baro":37000,"alt_geom":36650,"gs":549.3,"track":62.2,"baro_rate":0,"category":"A3","nav_qnh":1013.6,"nav_altitude_mcp":36992,"nav_heading":56.2,"lat":42.171346,"lon":-93.298198,"nic":8,"rc":186,"seen_pos":66.3,"version":2,"nic_baro":1,"nac_p":8,"nac_v":1,"sil":3,"sil_type":"perhour","gva":1,"sda":2,"mlat":[],"tisb":[],"messages":1205,"seen":7.4,"rssi":-26.0},
{"hex":"ac9e9a","category":"A4","version":2,"sil_type":"perhour","mlat":[],"tisb":[],"messages":746,"seen":119.1,"rssi":-26.6},
{"hex":"a96577","flight":"DAL673 ","alt_baro":40025,"alt_geom":39625,"gs":371.4,"track":265.1,"baro_rate":0,"squawk":"2641","emergency":"none","category":"A4","nav_qnh":1013.6,"nav_altitude_mcp":40000,"nav_heading":258.8,"lat":42.057220,"lon":-94.098337,"nic":8,"rc":186,"seen_pos":0.9,"version":2,"nic_baro":1,"nac_p":9,"nac_v":1,"sil":3,"sil_type":"perhour","gva":2,"sda":2,"mlat":[],"tisb":[],"messages":3021,"seen":0.3,"rssi":-21.8},
{"hex":"aa56db","category":"A3","version":2,"sil_type":"perhour","mlat":[],"tisb":[],"messages":1651,"seen":85.3,"rssi":-26.4}
]
}
My code:
import json
json_file = open('test.json')
aircraft_json = json.load(json_file)
for i in aircraft_json['aircraft']:
print(i['hex'],i['flight'],i['alt_baro'],i['alt_geom'],i['gs'],i['gs'],i['track'],i['baro_rate'],i[
'category'],i['nav_qnh'],i['nav_altitude_mcp'],i['lat'],i['lon'],i['nic'],i['rc'],i['seen_pos'],i['version'],i['nic_baro'],i['nac_p'],i['nac_v'],i['sil'],i['sil_type'],i['gva'],i['sda'],i['mlat'],i['tisb'],i['messages'],i['seen'],i['rssi'])
json_file.close()
Output:
Traceback (most recent call last):
File "/home/pi/aircraft_json_to_csv.py", line 11, in <module>
print(i['hex'],i['flight'],i['alt_baro'],i['alt_geom'],i['gs'],i['gs'],i['track'],i['baro_rate'],i[
KeyError: 'flight
The json file is updated every second and json file may miss key values like 'flight' or any random key values. My question is if that key is missing then how to replace those missing value with empty space without getting keyerror.
Thank you
My advice would be to give each field a suitable default value and store these fields in a dictionary.
Then, instead of assuming the field is present, check if the field exists. If it doesn't, then apply the default value.
Below is a simple example of this in action.
The defaults dict has been populated with a few possible defaults
to get you started, to which you would add the rest of the fields as well.
I've adapted the loop to iterate through the keys of the dict (all the known fields so to speak), and add the default value for any missing field.
import json
with open('aircraft.json') as json_file:
aircraft_json = json.load(json_file)
defaults = {
'alt_baro': 0,
'alt_geom': 0,
'version': 0,
'baro_rate': 0,
'mlat': [],
'tisb': []
# similarly for the other fields
}
for dat in aircraft_json['aircraft']:
for field in defaults.keys():
if field not in dat:
dat[field] = defaults[field]
print(dat[field], end=' ')
print('')
I have a JSON file contains fields such as machine_id, category, and ... Category contains states of machines such as "alarm", "failure". I simply like to see how many times each machine_id has been reported using rmr2.
For example, if I have the following:
machine_id, state
48, alarm
39, failure
48, utilization
I like to see this result:
48,2
39,1
What I did:
I wrote a simple mapreduce to read the value of JSON file and used it as an input in the second mapreduce. Code is:
mp = function(k,v){
machine_id=v$machine_id
keyval(machine_id,1) }
rd = function(k,v) keyval(k,length(v))
mapreduce(input = mapreduce(input='\user\cloudera\sample.json', input.format="json" , map=function(k,v) keyval(k,v)) , map=mp, reduce = rd)
Unfortunately, it returns only the last two values of JSON file. It seems that it doesn't read entire of the value of the JSON file. I would appreciate any help.
print [(element['name'], element['value']) for element in soup.find_all('input')]
I copied this code to get the value of an input and it throws this error:
File "messager.py", line 116, in main
print [(element['name'], element['value']) for element in soup.find_all('input')]
File "C:\PYTHON27\lib\site-packages\bs4\element.py", line 905, in __getitem__
return self.attrs[key]
KeyError: 'value'
If I only provide name, it works. I tried several other versions, but it still gives me the same value key error. It just seems it doesn't return value.
Either way, here's what it fully returns if I search for all 'inputs' (example of one result):
<input id="Token" name="data[Token][key]" type="hidden" value="152a1f397548bfecbb09581670734bf0403bdf63"/>
So it definitely finds the 'inputs' but it can't get the values.
Any ideas on why this happens?
Probably, there are input elements without value attribute being set.
You can let find_all() know that you want only the inputs with value and nameattributes set:
soup.find_all("input", {"name": True, "value": True})
BACKGROUND:
I am having issues trying to search through some CSV files.
I've gone through the python documentation: http://docs.python.org/2/library/csv.html
about the csv.DictReader(csvfile, fieldnames=None, restkey=None, restval=None, dialect='excel', *args, **kwds) object of the csv module.
My understanding is that the csv.DictReader assumes the first line/row of the file are the fieldnames, however, my csv dictionary file simply starts with "key","value" and goes on for atleast 500,000 lines.
My program will ask the user for the title (thus the key) they are looking for, and present the value (which is the 2nd column) to the screen using the print function. My problem is how to use the csv.dictreader to search for a specific key, and print its value.
Sample Data:
Below is an example of the csv file and its contents...
"Mamer","285713:13"
"Champhol","461034:2"
"Station Palais","972811:0"
So if i want to find "Station Palais" (input), my output will be 972811:0. I am able to manipulate the string and create the overall program, I just need help with the csv.dictreader.I appreciate any assistance.
EDITED PART:
import csv
def main():
with open('anchor_summary2.csv', 'rb') as file_data:
list_of_stuff = []
reader = csv.DictReader(file_data, ("title", "value"))
for i in reader:
list_of_stuff.append(i)
print list_of_stuff
main()
The documentation you linked to provides half the answer:
class csv.DictReader(csvfile, fieldnames=None, restkey=None, restval=None, dialect='excel', *args, **kwds)
[...] maps the information read into a dict whose keys are given by the optional fieldnames parameter. If the fieldnames parameter is omitted, the values in the first row of the csvfile will be used as the fieldnames.
It would seem that if the fieldnames parameter is passed, the given file will not have its first record interpreted as headers (the parameter will be used instead).
# file_data is the text of the file, not the filename
reader = csv.DictReader(file_data, ("title", "value"))
for i in reader:
list_of_stuff.append(i)
which will (apparently; I've been having trouble with it) produce the following data structure:
[{"title": "Mamer", "value": "285713:13"},
{"title": "Champhol", "value": "461034:2"},
{"title": "Station Palais", "value": "972811:0"}]
which may need to be further massaged into a title-to-value mapping by something like this:
data = {}
for i in list_of_stuff:
data[i["title"]] = i["value"]
Now just use the keys and values of data to complete your task.
And here it is as a dictionary comprehension:
data = {row["title"]: row["value"] for row in csv.DictReader(file_data, ("title", "value"))}
The currently accepted answer is fine, but there's a slightly more direct way of getting at the data. The dict() constructor in Python can take any iterable.
In addition, your code might have issues on Python 3, because Python 3's csv module expects the file to be opened in text mode, not binary mode. You can make your code compatible with 2 and 3 by using io.open instead of open.
import csv
import io
with io.open('anchor_summary2.csv', 'r', newline='', encoding='utf-8') as f:
data = dict(csv.reader(f))
print(data['Champhol'])
As a warning, if your csv file has two rows with the same value in the first column, the later value will overwrite the earlier value. (This is also true of the other posted solution.)
If your program really is only supposed to print the result, there's really no reason to build a keyed dictionary.
import csv
import io
# Python 2/3 compat
try:
input = raw_input
except NameError:
pass
def main():
# Case-insensitive & leading/trailing whitespace insensitive
user_city = input('Enter a city: ').strip().lower()
with io.open('anchor_summary2.csv', 'r', newline='', encoding='utf-8') as f:
for city, value in csv.reader(f):
if user_city == city.lower():
print(value)
break
else:
print("City not found.")
if __name __ == '__main__':
main()
The advantage of this technique is that the csv isn't loaded into memory and the data is only iterated over once. I also added a little code the calls lower on both the keys to make the match case-insensitive. Another advantage is if the city the user requests is near the top of the file, it returns almost immediately and stops looking through the file.
With all that said, if searching performance is your primary consideration, you should consider storing the data in a database.