I have a view that should generate a temporary JSON file and save this TempFile to the database. The content to this file, a dictionary named assets, is created using DRF using serializers. This file should be written to the database in a model called CollectionSnapshot.
class CollectionSnapshotCreate(generics.CreateAPIView):
permission_classes = [MemberPermission, ]
def create(self, request, *args, **kwargs):
collection = get_collection(request.data['collection_id'])
items = Item.objects.filter(collection=collection)
assets = {
"collection": CollectionSerializer(collection, many=False).data,
"items": ItemSerializer(items, many=True).data,
}
fp = tempfile.TemporaryFile(mode="w+")
json.dump(assets, fp)
fp.flush()
CollectionSnapshot.objects.create(
final=False,
created_by=request.user,
collection_id=collection.id,
file=ContentFile(fp.read(), name="assets.json")
)
fp.close()
return JsonResponse({}, status=200)
Printing assets returns the dictionary correctly. So I am getting the dictionary normally.
Following the solution below I do get the file saved to the db, but without any content:
copy file from one model to another
Seems that json.dump(assets, fp) is failing silently, or I am missing something to actually save the content to the temp file prior to sending it to the database.
The question is: why is the files in the db empty?
I found out that fp.read() throws content based on the current pointer in the file. At least, that is my understanding. So after I dump assets dict as json the to temp file, I have to bring back the cursor to the beggining using fp.seek(0). This way, when I call fp.read() inside file=ContentFile(fp.read(), ...) it actually reads all the content. It was giving me empty because there was nothing to read since the cursor was at the end of the file.
fp = tempfile.TemporaryFile(mode="w+")
json.dump(assets, fp)
fp.flush()
fp.seek(0) // important
CollectionSnapshot.objects.create // stays the same
Related
I am new to JSON file and i'm strugeling to get any information out of it.
The structure of the JSON file is as following:
Json file Structure
Now what I need is to access the "batches", to get the data from each variable.
I did try codes (shown below) i've found to reach deeper keys but somehow i still didnt get any results.
1.
def safeget(dct, *keys):
for key in keys:
try:
dct = dct[key]
except KeyError:
return None
return dct
safeget(mydata,"batches")
def dict_depth(mydata):
if isinstance(mydata, dict):
return 1 + (max(map(dict_depth, mydata.values()))
if mydata else 0)
return 0
print(dict_depth(mydata))
The final goal then would be to create a loop to extract all the information but thats something for the future.
Any help is highly appreciated, also any recommendations how i should ask things here in the future to get the best answers!
As far as I understood, you simply want to extract all the data without any ordering?
Then this should work out:
# Python program to read
# json file
import json
# Opening JSON file
f = open('data.json',)
# returns JSON object as
# a dictionary
data = json.load(f)
# Iterating through the json
# list
for i in data['emp_details']:
print(i)
# Closing file
f.close()
import com.jayway.jsonpath.JsonPath
def idCSV = new File('id.csv')
def index = [fileOne.json, fileTwo.json]
def jsonString
index.each { file ->
jsonString = ________
def ids = JsonPath.read(jsonString, '$..id')
ids.each { id ->
idCSV << id << newLine
}
}
How to fill the jsonString = ____, so that I can json file into string and parse the string to extract ids and some information from the json string.
And I don't to do it in http request-> GET-> file format.
Previously i have extraced jsonString from http response and it worked well now I want to do it this way.
Use JsonSlurper:
def jsonString = new groovy.json.JsonSlurper().parseText(new File("json.txt").text)
My expectation is that you're looking for File.getText() function
jsonString = file.text
I have no full vision why do you need to store the values from JSON in a CSV file, however there is an alternative way of achieving this which doesn't require scripting as your approach will work with 1 concurrent thread only, if you will add more users attempting writing into the same file - you'll run into a race condition :
You can read the files from the folder into JMeter Variables via Directory Listing Config
The file can be read using HTTP Request sampler
The values cane be fetched using JSON Extractor, they will be automatically stored into JMeter Variables so you will able to use them later on
If you need the values to be present in the file (although I wouldn't recommend this approach cause it will cause massive disk IO and potentially can run your test) you can go for the Flexible File Writer
I'm uploading a json file via flask, but I'm having trouble actually reading what is in the file.
# named fJson b/c of other json imports
from flask import json as fJson
#app.route('/upload', methods=['GET', 'POST'])
def upload():
if request.method == 'POST':
file = request.files['file']
# data = fJson.load(file)
# myfile = file.read()
I'm trying to deal with this by using the 'file' variable. I looked at http://flask.pocoo.org/docs/0.10/api/#flask.json.load, but I get the error "No JSON object could be decoded". I also looked at Read file data without saving it in Flask which recommended using file.read(), but that didn't work, returns either "None" or "".
Request.files
A MultiDict with files uploaded as part of a POST or PUT request. Each file is stored as FileStorage object. It basically behaves like a standard file object you know from Python, with the difference that it also has a save() function that can store the file on the filesystem.
http://flask.pocoo.org/docs/0.10/api/#flask.Request.files
You don't need use json, just use read(), like this:
if request.method == 'POST':
file = request.files['file']
myfile = file.read()
For some reason the position in the file was at the end. Doing
file.seek(0)
before doing a read or load fixes the problem.
Say I have a function that reads a .txt file and creates arrays based on the columns of the data within that file. What I have right now inside the function looks like:
data = open("some_file_name.txt","r")
But if I want to change the .txt file that the function reads I have to manually go into the code and type in the new file name before running it again. Instead, how can I pass any file name to the function so it looks like:
my_function(/filepath/some_file_name.txt):
data = open("specified_file_name.txt","r")
I think you want
def my_function(filepath):
data = open(filepath, "r")
...
and then
my_function("/filepath/some_file_name.txt")
or better:
def my_function(data):
...
and then
with open("/filepath/some_file_name.txt", "rb") as data:
my_function(data)
The latter version lets you pass in any file-like object to my_function().
Update: if you want to get fancy and allow file names or file handles:
def my_func(data):
if isinstance(data, basestring):
with open(data, 'rb') as f:
return my_func(f)
...
I need to test a various links of a site (no need to login) with 100's of users and loop it for some number of times using JMeter. I want to put those links in a "CSV file", so that all the links to be tested are read from file.
How do I accomplish this task?
Prepare kind of csv-file with list of your test-params and use it to parametrize your test-samplers, using at least the following:
CSV Data Set Config
Look into the following links for details:
How to get Jmeter to use CSV data for GET parameters?
Use jmeter to test multiple Websites
use csv parameters in jmeter httprequest path
Force a thread to use same input line when using CSV Data Set Config
Jmeter functions:
__CSVRead,
__StringFromFile.
Variables From CSV sampler from jmeter-plugins.
1. Prepare your test-urls in csv-file, e.g. in the following format:
url1
url2
...
urlN
Ensure that test-URLs don't contain http:// prefix (as per HTTP Request params -> Server).
2. Use schema for your script as below:
CSV Data Set Config:
Filename: [path to your csv-file with test-urls]
Variable Names: testURL
Recycle on EOF?: True
Stop thread on EOF?: False
Sharing mode: Current thread
Thread Group:
Number of Threads: N
Loop Count: M
HTTP Request // your http call
Server Name or IP: ${testURL} // use variable with extracted URL
This will start N users, each users will read M entries from list of test-urls. If M > number of entries in list of test-urls then user will recycle the list on EOF.
In one of the comments, it's mentioned that you can't read the CSV more than once per loop. You can go and have multiple threads, each reading the CSV file once, but then the file is close and won't be read on the next loop. Also, if you set the CSV to recycle, then CSV file is read over and over again indefinitely. So the question becomes how do you loop a CSV file a certain number of times as opposed to indefinitely?
I posted my answer to that in another post (https://stackoverflow.com/a/64086009/4832515), but I'll copy & paste it incase that link doesn't work in the future.
I couldn't find a simple solution to this. I ended up using beanshell scripts, which let you use code very similar to java to do some custom stuff. I made an example JMeter project to demonstrate how to do this (yes it's ridiculously complicated, considering all I want to do is repeat the CSV read):
Files:
my file structure:
JMeterExample
|
⊢--JMeterTests.jmx // the JMeter file
⊢--example.csv // the CSV file
contents of my CSV:
guest-id-1,"123 fake street",
guest-id-2,"456 fake street",
guest-id-3,"789 fake street",
so in this thread group, I'm going to just have 1 user, and I'll loop 2 times. I intend to send 1 request per CSV line. So there should be 6 requests sent total.
Thread Group
User Defined Variables
This is kind of optional, but the filepath is subject to change, and I don't like changing my scripts just for a change in configuration. So I store the CSV filename in a "User Defined Variables" node.
If you are storing the CSV file in the same directory as your JMeter test, you can just specify the filename only.
If you are saving the CSV in a folder other than the directory containing your JMeter file, you will need to supply an absolute path, and then slightly modify the beanshell script below: you'll need to comment out the line that loads the file relatively, and comment in the line that loads from an absolute path.
BeanShell Sampler to parse and store CSV lines
Add a Beanshell Sampler which will basically take in a path, and parse & store each line as a variable. The first line will be stored as a variable called csv_line_0, the 2nd line will be csv_line_1 and so on. I know it's not a clean solution but... I can't find any clean simple way of doing this clean simple task. I copied and pasted my code below.
import org.apache.jmeter.services.FileServer;
import java.text.*;
import java.io.*;
import java.util.*;
String temp = null;
ArrayList lines = new ArrayList();
BufferedReader bufRdr;
ArrayList strList = new ArrayList();
// get the file
try {
// you can use this line below if your csvFilePath is an absolute path
// File file = new File(${csvFilePath});
// you can use this line below if your csvFilepath is a relative path, relative to where you saved this JMeter file
File file = new File(org.apache.jmeter.services.FileServer.getFileServer().getBaseDir() + "/" + ${csvFilePath});
if (!file.exists()) {
throw new Exception ("ERROR: file " + filename + " not found");
}
bufRdr = new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF8"));
} catch(Exception e){
log.error("failed to load file");
log.error(e.getMessage());
return;
}
// For each CSV line, save it to a variable
int counter = 0;
while(true){
try{
temp = bufRdr.readLine();
if(temp == null || temp.equals("<EOF>")){
break;
}
lines.add(temp);
vars.put("csv_line_" + String.valueOf(counter), temp);
counter++;
} catch(Exception e){
log.error("failed to get next line");
log.error(e.getMessage());
break;
}
}
// store the number of CSV lines there are for the loop counter
vars.put("linesCount", String.valueOf(lines.size()));
Loop Controller
Add a Loop Controller that loops once for each CSV line. ${linesCount} is a count of the number of CSV lines and is calculated from the above beanShell script.
Beanshell script to extract data from current CSV Line
This script will run once per CSV line. It will go and grab the current line, and parse out whatever data is on it. You'll have to modify this script to get the data you want. In my example, I only had 2 columns, where column 1 is a "guestId", and column 2 is an "address".
__jm__loopController__idx is a variable JMeter defines for you, and is the index of the loop controller. The variable name is __jm__{loop controller name}__idx.
String index = vars.get("__jm__loopController__idx");
String line = vars.get("csv_line_" + index);
String [] tokens = line.split(",");
vars.put("guestId", tokens[0]);
vars.put("address", tokens[1]);
Http request sampler
Here's the HTTP request that's using the data extracted.
result
When running this, as desired, I end up sending 6 http requests over to the endpoint I defined.