I am trying to send a jsonArray from my javacode to my nodeJS application, but i keep getting this error on my nodejs side, which i have trouble understanding why this is? As sending a normal JSONObject works fine. Any help would be greatly appreciated!
SyntaxError: Unexpected token C in JSON at position 1
at JSON.parse (<anonymous>)
at parse (E:\Visual code projects\NodeJS\node_modules\body-parser\lib\types\json.js:89:19)
at E:\Visual code projects\NodeJS\node_modules\body-parser\lib\read.js:121:18
at invokeCallback (E:\Visual code projects\NodeJS\node_modules\raw-body\index.js:224:16)
at done (E:\Visual code projects\NodeJS\node_modules\raw-body\index.js:213:7)
at IncomingMessage.onEnd (E:\Visual code projects\NodeJS\node_modules\raw-body\index.js:273:7)
at IncomingMessage.emit (events.js:387:35)
at endReadableNT (internal/streams/readable.js:1317:12)
at processTicksAndRejections (internal/process/task_queues.js:82:21)
The json array i am sending to the nodeJS app looks like this:
[Candlestick[openTime=1629028800000,open=45923.57000000,high=46070.00000000,low=45700.44000000,close=45808.00000000,volume=1372.55048700,closeTime=1629032399999,quoteAssetVolume=62946206.41606293,numberOfTrades=42003,takerBuyBaseAssetVolume=699.78407800,takerBuyQuoteAssetVolume=32095106.77383602],
Candlestick[openTime=1629032400000,open=45808.00000000,high=46070.00000000,low=45500.00000000,close=46050.00000000,volume=1911.24599100,closeTime=1629035999999,quoteAssetVolume=87529798.03243646,numberOfTrades=53351,takerBuyBaseAssetVolume=905.77985600,takerBuyQuoteAssetVolume=41495114.05028976],
Candlestick[openTime=1629036000000,open=46049.99000000,high=46498.89000000,low=45759.91000000,close=45862.84000000,volume=2612.72490800,closeTime=1629039599999,quoteAssetVolume=120720724.93845534,numberOfTrades=67231,takerBuyBaseAssetVolume=1326.32927300,takerBuyQuoteAssetVolume=61298610.46515451],
Candlestick[openTime=1629039600000,open=45862.84000000,high=46199.50000000,low=45810.73000000,close=46167.90000000,volume=1398.39949000,closeTime=1629043199999,quoteAssetVolume=64323828.51794621,numberOfTrades=40297,takerBuyBaseAssetVolume=745.55851400,takerBuyQuoteAssetVolume=34296263.66869613]]
This is my java code where i get candlestick data from an api and then convert it to a json array. And then post the jsonarray to my nodejs endpoint.
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.List;
public class HttpPostToNode {
public JSONArray convertCandleToJSON(List<Candlestick> candlesticks) {
JSONArray jsonArray = new JSONArray();
for (Candlestick candlestick : candlesticks) {
jsonArray.add(candlestick);
}
System.out.println(jsonArray.toJSONString());
return jsonArray;
}
public void post(String uri, String data) throws Exception {
HttpClient client = HttpClient.newBuilder().build();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create(uri))
.header("Content-Type", "application/json") //Must be this content type to post JSON to nodejs
.POST(HttpRequest.BodyPublishers.ofString(data))
.build();
HttpResponse<?> response = client.send(request, HttpResponse.BodyHandlers.discarding());
System.out.println(response.statusCode());
}
public static void main(String[] args) throws Exception {
HttpPostToNode httpost = new HttpPostToNode();
DownloadCandles d = new DownloadCandles(TimeStamps.monthAgo(), "BTCUSDT");
d.asyncGetCandles();
while (!d.downloadReady) {
Thread.sleep(50);
}
if (d.downloadReady) {
System.out.println("Download ready");
}
JSONArray jsonArray = httpost.convertCandleToJSON(d.candles);
httpost.post(AlgoConstants.API_END_POINT_CANDLESTICK, jsonArray.toJSONString());
}
}
My nodejs code:
var port = 8080;
const { json } = require('body-parser');
const express = require('express');
const app = express();
app.use(express.static('public'));
app.use(express.json({limit:'1mb'}));
app.post('/API', (req, res) => {
const jsonArray = JSON.parse(req.body);
console.log(jsonArray);
})
app.listen(port, () => {
console.log('Server is up on port ' port)
})
CodePudding user response：
Json is invalid.
- It should be wrapped as an object
- keys have to be wrapped with double quetes
- key cannot appeared more then one occurrence in same object.
=symbol not valid in json and you have to to separate between key and value with:
I have fixed the json down here:
{
"Candlestick": [
{
"openTime": 1629028800000,
"open": 45923.57,
"high": 46070.0,
"low": 45700.44,
"close": 45808.0,
"volume": 1372.550487,
"closeTime": 1629032399999,
"quoteAssetVolume": 62946206.41606293,
"numberOfTrades": 42003,
"takerBuyBaseAssetVolume": 699.784078,
"takerBuyQuoteAssetVolume": 32095106.77383602
},
{
"openTime": 1629032400000,
"open": 45808.0,
"high": 46070.0,
"low": 45500.0,
"close": 46050.0,
"volume": 1911.245991,
"closeTime": 1629035999999,
"quoteAssetVolume": 87529798.03243646,
"numberOfTrades": 53351,
"takerBuyBaseAssetVolume": 905.779856,
"takerBuyQuoteAssetVolume": 41495114.05028976
},
{
"openTime": 1629036000000,
"open": 46049.99,
"high": 46498.89,
"low": 45759.91,
"close": 45862.84,
"volume": 2612.724908,
"closeTime": 1629039599999,
"quoteAssetVolume": 120720724.93845535,
"numberOfTrades": 67231,
"takerBuyBaseAssetVolume": 1326.329273,
"takerBuyQuoteAssetVolume": 61298610.46515451
},
{
"openTime": 1629039600000,
"open": 45862.84,
"high": 46199.5,
"low": 45810.73,
"close": 46167.9,
"volume": 1398.39949,
"closeTime": 1629043199999,
"quoteAssetVolume": 64323828.51794621,
"numberOfTrades": 40297,
"takerBuyBaseAssetVolume": 745.558514,
"takerBuyQuoteAssetVolume": 34296263.66869613
}
]
}
Try to work with valid json
Java side solution
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.List;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
/**
* The type Http post to node.
*/
public class HttpPostToNode {
private static final ObjectMapper objectMapper = new ObjectMapper();
/**
* Convert candle to json string.
*
* @param candlesticks the candlesticks
* @return the string
* @throws JsonProcessingException the json processing exception
*/
public String convertCandleToJSON(List<Candlestick> candlesticks) throws JsonProcessingException {
return objectMapper.writeValueAsString(candlesticks);
}
/**
* Post.
*
* @param uri the uri
* @param data the data
* @throws Exception the exception
*/
public void post(String uri, String data) throws Exception {
HttpClient client = HttpClient.newBuilder().build();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create(uri))
.header("Content-Type", "application/json") //Must be this content type to post JSON to nodejs
.POST(HttpRequest.BodyPublishers.ofString(data))
.build();
HttpResponse<?> response = client.send(request, HttpResponse.BodyHandlers.discarding());
System.out.println(response.statusCode());
}
/**
* The entry point of application.
*
* @param args the input arguments
* @throws Exception the exception
*/
public static void main(String[] args) throws Exception {
HttpPostToNode httpost = new HttpPostToNode();
DownloadCandles d = new DownloadCandles(TimeStamps.monthAgo(), "BTCUSDT");
d.asyncGetCandles();
while (!d.downloadReady) { // Improve this while wih retryable method
Thread.sleep(50);
}
System.out.println("Download ready");
String json = httpost.convertCandleToJSON(d.candles);
httpost.post(AlgoConstants.API_END_POINT_CANDLESTICK,json);
}
}