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JSON to Data Frame

This repository provides a Common Lisp library to convert JSON data into a data frame using the json-to-df package. The package leverages the yason library for JSON parsing and dfio for data frame operations.

Installation

Clone the repository into your Quicklisp local-projects directory:

git clone https://github.com/gassechen/json-to-data-frame.git ~/quicklisp/local-projects

Load the package in your REPL:
```
(ql:quickload :json-to-df)
```
Switch to the json-to-df package:
```
(in-package :json-to-df)
```

Example Usage

Step 1: Define the URL for the JSON API

(defparameter *url* "https://jsonplaceholder.typicode.com/posts")

Step 2: Define a function to call the API and parse the JSON response

(defun call-api (url-get)
  (let* ((yason:*parse-json-booleans-as-symbols* t)
         (yason:*parse-json-arrays-as-vectors* nil)
         (respuesta
           (yason:parse
            (dex:get url-get
                     :keep-alive t
                     :use-connection-pool t
                     :connect-timeout 60
                     :want-stream t))))
    respuesta))

Step 3: Convert the JSON response to a data frame

(json-to-df (call-api *url*))

You will be prompted to select a symbol to be made accessible in the DFIO package:

Select a symbol to be made accessible in package DFIO:
  1. DATA-FRAME::BODY
  2. DFIO::BODY

Enter an integer (between 1 and 2): 1

Step 4: Display the data frames

(lisp-stat:show-data-frames)

Step 5: Assign the data frame to a variable and print it

(json-to-df (call-api *url*) "my-df")
(lisp-stat:show-data-frames)

Step 6: Print the data frame

(df:print-data my-df)

Output

The df:print-data function will print the contents of the data frame my-df:

JSON-TO-DF> (df:print-data my-df)

;; Output will display the data frame contents here

New function

(defun get-from-url (url-get &optional (df-name "DF") (key nil))

;;with name df
JSON-TO-DF> (get-from-url "https://jsonplaceholder.typicode.com/users" "usersDF")
#<DATA-FRAME:DATA-FRAME (9 observations of 15 variables)>

;;with key

JSON-TO-DF> (get-from-url "https://www.swapi.tech/api/planets/" "planetsDF" "results")
#<DATA-FRAME:DATA-FRAME (9 observations of 3 variables)>

New function

(defun get-from-file (file-path &optional (df-name "DF") (key nil))

JSON-TO-DF> (get-from-file "../tests/files/simpleobj.json" "filesimple")
#<DATA-FRAME:DATA-FRAME (2 observations of 3 variables)>

JSON-TO-DF> (get-from-file "../tests/files/multiplekesy.json" "multiplekey"  "empleados")
#<DATA-FRAME:DATA-FRAME (1 observations of 8 variables)>

TEST

JSON-TO-DF> (asdf:test-system 'json-to-df)

PROGRESS:

JSON-TO-DF-SUITE: (Test Suite)
    TEST-JSON-COMPLEXOBJ: E
    TEST-JSON-SIMPLEOBJ: 
    TEST-JSON-MULTIPLEKEY: 
    TEST-JSON-NESTEDFILEANDARRAY: 
    TEST-JSON-NESTEDFILE: 
    TEST-JSON-SIMPLEFILE: 
    TEST-JSON-PLANETS: 
    TEST-JSON-COUNTRIES: 
    TEST-JSON-USERS: 
    TEST-JSON-PLACEHOLDER:

FAILURE DETAILS:

JSON-TO-DF-SUITE: (Test Suite)
    TEST-JSON-COMPLEXOBJ: The value

(#<HASH-TABLE :TEST EQUAL :COUNT 3 {1015B12FB3}>) is not of type HASH-TABLE

SUMMARY:

Test functions:
    Executed: 10
    Skipped:  0

Tested 1 assertion.
    Errors: 1/1 all tests had errors

This README provides a clear and concise guide on how to use the json-to-df package to convert JSON data into a data frame and display it.