I've created a basic client and server that pass a string, which I've changed to JSON instead. But the JSON string is only parsable before it gets sent through TCP. After it's sent, the string version is identical (after a chomp), but on the server side it no longer processes the JSON correctly. Here is some of my code (with other bits trimmed)
Some of the client code
require 'json'
require 'socket'
foo = {'a' => 1, 'b' => 2, 'c' => 3}
puts foo.to_s + "......."
foo.to_json
puts foo['b'] # => outputs the correct '2' answer
client = TCPSocket.open('localhost', 2000)
client.puts json
client.close;
Some of the server code
require 'socket'
require 'json'
server = TCPServer.open(2000)
while true
client = server.accept # Accept client
response = client.gets
print response
response = response.chomp
response.to_json
puts response['b'] # => outputs 'b'
end
The output 'b' should be '2' instead. How do I fix this?
Thanks
In your server you wrote response.to_json. This turns a string to JSON, then throws it away. And I don't like the .chomp, either.
Try
response = client.gets
hash = JSON.parse(response)
Now hash is a Ruby Hash object with your data in it, and hash['b'] should work correctly.
The problem is that .to_json does not parse JSON inside a string and replace itself with the result. It is used to convert the string into a format that is an acceptable JSON value.
require 'json'
string = "abc"
puts string
puts string.to_json
This will output:
abc
"abc"
The method is added to the String class by the JSON generator and it uses it internally to generate the JSON document.
But why does your response['b'] return "b"?
Because Ruby strings have a method called [] that can be used to:
Return a substring: "abc"[0,2] => "ab"
Return a single character from index: "abc"[1] => "b"
Return a substring if the string contains it: "abc"["bc"] => "bc", "abc"["fg"] => nil
Return a regexp match: "abc"[/^a([a-z])c/, 1] => "b"
and possibly some other ways I can't think of right now.
So this happens because your response is a string that has the character "b" in it:
response = "something with a b"
puts response["b"]
# outputs b
puts response["x"]
# outputs a blank line because response does not contain "x".
Instead of .to_json your code has to call JSON.parse or JSON.load:
data = JSON.parse(response)
puts data['b']
Related
First, I have a json:
json = "{\"string_1\": \"{{string_1_value}}\", \"number_1\": \"{{number_1_value}}\"}"
And this hash:
hash = {
"{{string_1_value}}" => "test" //string
"{{number_1_value}}" => 2 //integer
}
What I'd like to do is to replace json with this hash and generate below json.
"{\"string_1\": \"test\", \"number_1\": 2}"
When I do this by String#gsub, I got an Error.
hash.map {|k, v| json.gsub!(k, v)}
=> TypeError (no implicit conversion of Integer into String)
I don't want 2 to be string, i.e.)
"{"string_1": "test", "number_1": "2"}"
Do you have any idea?
Thank you in advance.
First, in ruby comments are marked by # not //. And remember about the comma in hash.
gsub is not the fastest way to replace things, it's better to convert json to regular hash and then convert it again to json.
require 'json'
json = "{\"string_1\": \"{{string_1_value}}\", \"number_1\": \"{{number_1_value}}\"}"
hash = {
"{{string_1_value}}" => "test", #string
"{{number_1_value}}" => 2 #integer
}
# First you should parse your json and change it to hash:
parsed_json = JSON.parse(json)
# Then create keys array
keys = parsed_json.keys
# Create new empty hash
new_hash = {}
# And now fill new hash with keys and values
# (take a look at to_s, it converts values to a String)
hash.each.with_index do |(_k, v), i|
new_hash[keys[i]] = v.to_s
end
# Convert to json at the end
new_hash.to_json
# => "{\"string_1\":\"test\",\"number_1\":\"2\"}"
You can use the Regexp,Hash version of String#gsub to just substitute the patterns with the desired values as follows:
require 'json'
json_string = "{\"string_1\": \"{{string_1_value}}\", \"number_1\": \"{{number_1_value}}\"}"
original_hash= {
"{{string_1_value}}" => "test", #string
"{{number_1_value}}" => 2 #integer
}
#Convert JSON to hash and invert the key value pairs
parsed_json = JSON.parse(json_string).invert
#=>{"{{string_1_value}}"=>"string_1", "{{number_1_value}}"=>"number_1"}
# Convert the hash to JSON and substitute the patterns
original_hash.to_json.gsub(/\{\{.+?\}\}/, parsed_json)
#=> "{\"string_1\":\"test\",\"number_1\":2}"
I'm trying to send a dict to javascript via port for storing the value in localStorage, and retrieve it next time the Elm app starts via flag.
Below code snippets show the dict sent as well as the raw json value received through flag. The Json decoding fails showing the error message at the bottom.
The issue seems to be the extra backslashes (as in \"{\\"Left\\") contained in the raw flag value. Interestingly, console.log shows that the flag value passed by javascript is "dict1:{"Left":"fullHeightVerticalCenter","Right":"fullHeightVerticalCenter","_default":"fullHeightVerticalBottom"}"as intended, so the extra backslashes seem to be added by Elm, but I can't figure out why. Also, I'd be interested to find out a better way to achieve passing a dict to and from javascript.
import Json.Decode as JD
import Json.Encode as JE
dict1 = Dict.fromList[("_default", "fullHeightVerticalBottom")
, ("Left", "fullHeightVerticalCenter")
, ("Right", "fullHeightVerticalCenter")]
type alias FlagsJEValue =
{dict1: String}
port setStorage : FlagsJEValue -> Cmd msg
-- inside Update function Cmd
setStorage {dict1 = JE.encode 0 (dictEncoder JE.string model.dict1)}
dictEncoder enc dict =
Dict.toList dict
|> List.map (\(k,v) -> (k, enc v))
|> JE.object
--
type alias Flags =
{dict1: Dict String String}
flagsDecoder : Decoder Flags
flagsDecoder =
JD.succeed Flags
|> required "dict1" (JD.dict JD.string)
-- inside `init`
case JD.decodeValue MyDecoders.flagsDecoder raw_flags of
Err e ->
_ = Debug.log "raw flag value" (Debug.toString (JE.encode 2 raw_flags) )
_ = Debug.log "flags error msg" (Debug.toString e)
... omitted ...
Ok flags ->
... omitted ...
-- raw flag value
"{\n \"dict1\": \"{\\\"Left\\\":\\\"fullHeightVerticalCenter\\\",\\\"Right\\\":\\\"fullHeightVerticalCenter\\\",\\\"_default\\\":\\\"fullHeightVerticalBottom\\\"}\"\n}"
--flags error msg
"Failure \"Json.Decode.oneOf failed in the following 2 ways:\\n\\n\\n\\n
(1) Problem with the given value:\\n \\n \\\"{\\\\\\\"Left\\\\\\\":\\\\\\\"fullHeightVerticalCenter\\\\\\\",\\\\\\\"Right\\\\\\\":\\\\\\\"fullHeightVerticalCenter\\\\\\\",\\\\\\\"_default\\\\\\\":\\\\\\\"fullHeightVerticalBottom\\\\\\\"}\\\"\\n \\n Expecting an OBJECT\\n\\n\\n\\n
(2) Problem with the given value:\\n \\n \\\"{\\\\\\\"Left\\\\\\\":\\\\\\\"fullHeightVerticalCenter\\\\\\\",\\\\\\\"Right\\\\\\\":\\\\\\\"fullHeightVerticalCenter\\\\\\\",\\\\\\\"_default\\\\\\\":\\\\\\\"fullHeightVerticalBottom\\\\\\\"}\\\"\\n \\n Expecting null\" <internals>”
You don't need to use JE.encode there.
You can just use your dictEncoder to produce a Json.Encode.Value and pass that directly to setStorage.
The problem you're encountering it that you've encoded the dict to a json string (using JE.encode) and then sent that string over a port and the port has encoded that string as json again. You see extra slashes because the json string is double encoded.
Searched online and read through the documents, but have not been able to find an answer. I am fairly new and part of learning Ruby I wanted to make the script below.
The Script essentially does a Carrier Lookup on a list of numbers that are provided through a CSV file. The CSV file has just one row with the column header "number".
Everything runs fine UNTIL the API gives me an output that is different from the others. In this example, it tells me that one of the numbers in my file is not a valid US number. This then causes my script to stop running.
I am looking to see if there is a way to either ignore it (I read about Begin and End, but was not able to get it to work) or ideally either create a separate file with those errors or just put the data into the main file.
Any help would be much appreciated. Thank you.
Ruby Code:
require 'csv'
require 'uri'
require 'net/http'
require 'json'
number = 0
CSV.foreach('data1.csv',headers: true) do |row|
number = row['number'].to_i
uri = URI("https://api.message360.com/api/v3/carrier/lookup.json?PhoneNumber=#{number}")
req = Net::HTTP::Post.new(uri)
req.basic_auth 'XXX' , 'XXX'
res = Net::HTTP.start(uri.hostname, uri.port, :use_ssl => true) {|http|
http.request(req)
}
json = JSON.parse(res.body)
new = json["Message360"]["Carrier"].values
CSV.open("new.csv", "ab") do |csv|
csv << new
end
end
File Data:
number
5556667777
9998887777
Good Response example in JSON:
{"Message360"=>{"ResponseStatus"=>1, "Carrier"=>{"ApiVersion"=>"3", "CarrierSid"=>"XXX", "AccountSid"=>"XXX", "PhoneNumber"=>"+19495554444", "Network"=>"Cellco Partnership dba Verizon Wireless - CA", "Wireless"=>"true", "ZipCode"=>"92604", "City"=>"Irvine", "Price"=>0.0003, "Status"=>"success", "DateCreated"=>"2018-05-15 23:05:15"}}}
The response that causes Script to stop:
{
"Message360": {
"ResponseStatus": 0,
"Errors": {
"Error": [
{
"Code": "ER-M360-CAR-111",
"Message": "Allowed Only Valid E164 North American Numbers.",
"MoreInfo": []
}
]
}
}
}
It would appear you can just check json["Message360"]["ResponseStatus"] first for a 0 or 1 to indicate failure or success.
I'd probably add a rescue to help catch any other errors (malformed JSON, network issue, etc.)
CSV.foreach('data1.csv',headers: true) do |row|
number = row['number'].to_i
...
json = JSON.parse(res.body)
if json["Message360"]["ResponseStatus"] == 1
new = json["Message360"]["Carrier"].values
CSV.open("new.csv", "ab") do |csv|
csv << new
end
else
# handle bad response
end
rescue StandardError => e
# request failed for some reason, log e and the number?
end
I am trying out a simple program
import json
class unified_response():
trinitiversion="3"
preprocess = []
if __name__ == '__main__':
ur = unified_response()
preprocessValDict = dict()
preprocessValDict["input"] = "some string"
preprocessValDict["correct"] = " correct some string"
ur.preprocess.append(preprocessValDict)
s = json.dumps(unified_response.__dict__)
print s
s = json.dumps(ur.__dict__)
print s
First print statement prints
{"preprocess": [{"input": "some string", "correct": " correct some string"}], "trinitiversion": "3", "__module__": "__main__", "__doc__": null}
Second print statement prints
{}
Why is the second object not printing any values?
This is not related at all to the json module.
ur.__dict__ is an empty dictionary since only instance attributes are saved in the instance.
The unified_response class only has class attributes hence ur.__dict__ is an empty dict which json.dumps transforms to an empty string.
Compare the outputs of print unified_response.__dict__ and print ur.__dict__.
As a side note:
ur.preprocess.append(preprocessValDict)
Accessing (and especially modifying) class attributes through an instance is considered a bad practice as it can lead to hard-to-find bugs.
I need to extract only the value for 'admins' from this Json using Ruby :
JSON -
{
"Roles":[
{
"admins":[
"me"
],
"role":"cleanup"
},
{
"admins":[
"tester"
],
"role":"create a mess"
},
]
}
RUBY -
require 'json'
file = File.read('adminlist_Feb_2017.json')
thismonthlist=JSON.parse(file)
puts thismonthlist['admins']
Output - this gives me a blank output however if i change the last line to :
puts thismonthlist['Roles']
it gives me everything. I just want the list of admins.
Try something like this
thismonthlist[:Roles].flat_map { |role| role[:admins] }
=> ["me", "tester"]
admins = []
File.open('adminlist_Feb_2017.json', 'r') do |file|
json = JSON.parse(file.read)
admins = json["Roles"].flat_map{|role| role["admins"]}.uniq
end
admins
# => ["me", "tester"]
I open the file and process it in a block to ensure it's closed at the end. In the block I read the file content and parse the json string into a hash. Then I go through the "Roles" of the hash, grab the "admins" arrays and return it as one array only with Enumerable#flat_map. After I use Enumerable#uniq to return each admin only once.