JSON response react native Post method problem - json

I am facing a strange problem, I am using Nexmo to verify number, and I am sending a post method
fetch('http://monasabat-app.com/basta_app/sign_up.php', {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/x-www-form-urlencoded'
},
body: formBody
}).then((response) => response.json())
.then((responseJson) => {
const ss1 = responseJson.status[0]
console.log(ss1)
let success = 'success'
if(ss1.status === success){
alert(ss1.status)
this.props.navigation.navigate('verNum',{
uid:ss1.uid,
phone:this.state.phone,
name:this.state.name,
emai:this.state.email
})
}else{
alert(ss1.status)
}
The sign up info(formBody) is successfully stored in the database but it doesn't navigate to the verNum screen neither alert the ss1.status but if the response is not success it does alert ss1.status in the else part (num is already registered) so I guess the problem is in the if condition part but the strange thing it does work sometimes and it doesn't some other times with a warning Possible Unhandled Promise Rejection (id: 1).
My JSON response
{
"status": [
{
"status": "success",
"uid": "99"
}
]
}

First, check if the this.props and this.state is accessible inside the promise.
If not before fetch create a variable that takes the value of this
Example let self = this;
then
this.props.navigation.navigate
would become
self.props.navigation.navigate.

Related

React native fetch returns _bodyBlob _bodyInit headers etc instead of json with json()

after resinstalling node_modules and using json() to my fetch call, I still receive an blob response. Here is my code :
export function test() {
const url = 'http://url/api/testServlet';
return fetch(url, {
method: 'GET',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json'
}
})
.then((data) => {
console.log("data ", data, " --- end data");
data.json();
})
.catch((error) => {
console.error(error);
});
}
With console.log, I get :
data
{
"_bodyBlob": {
blob
},
"_bodyInit": {
blob
},
"headers": {
headers
},
"ok": true,
"status": 200,
"statusText": undefined,
"type": "default",
"url": "http://url/api/testServlet"
}
--- fin data
Thank you very much for your help
EDIT :
I have olso an error value.hasOwnProperty('tag') that comes from nowhere I have absolutely no idea from where that comes from... I have just a component that display the result of my API call and the code I showed above.
The message is :
"Error: value.hasOwnProperty is not a function. (In 'value.hasOwnProperty('tag'), 'value.hasOwnProperty' is undefined)
I read some subjects and all was talking about this error but there was the function hasOwnProperty written in there code. Not me...
My bad. Or not. I don't know you tell me. I replaced by :
export function test() {
return fetch('http://url/api/testServlet')
.then((response) => response.json())
.then((responseJson) => {
console.log("data : ", responseJson)
return responseJson;
})
.catch((error) => {
console.error(error);
});
}
And it worked. It may come from the const url I don't know but I'm happy. Thank you. Or thank me I don't know you tell me.

keeps fetching the old json data?

I'm trying to fetch a json file from a https link however, no matter what link a give the result does not change!?
I validated all the json files. in case they had an error.
the responseData stays the same, and even when I force the data to change by instead returning responseData returning a json manually written; it changes right back to the old json data that just doesnt change when I return responseData back.
And the responseData that I requested to be be posted on the console gives the wrong information
The url given is correct.
but the output doesnt correspond to the data when I fill the link in the internetbrowser.
constructor(props){
super(props);
this.state = {
connected: false,
}
this.init = this.init.bind(this);
this.getJson = this.getJson.bind(this);
this.updateVisited = this.updateVisited.bind(this);
}
init = async ({json})=>{
if(json==null){
await AsyncStorage.setItem('database', "");
alert('error occured');
} else {
await AsyncStorage.setItem('database', JSON.stringify(json));
this.setState({
connected: true
});
}
}
getJson = async ()=>{
var url = await AsyncStorage.getItem("database_url");
console.log(url);
return fetch(url,
{
method: "GET",
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
},
})
.then(response => response.json())
.then(responseData => {
this.updateVisited(url);
console.log(responseData);
return responseData;
})
.catch(error => {
alert('Could not connect!');
return null;
})
}
connect = async ({url})=>{
await AsyncStorage.setItem("database_url", url);
this.getJson().then(json => this.init({json}));
}
"a_json": [{"name": "greg"}]
"test": [{"name": "sheldon"}]
"temp": [{"name": "bob"}]
when the url points to the json test it gives bob expecting sheldon
when the url points to the json temp it gives bob expecting bob
when the url points to the json a_json it gives bob expecting greg
when returning a json without trying to fetch it from the internet at the place of responseData; it gives the expecting value
If you need more information, feel free to ask.
Thank you for your time reading my question.
The problem was the Cache-Control.
I added 'Cache-Control': 'no-cache' to the header of the fetch, which fixed the problem!
This was pointed out by #Pritish Vaidya in the comments

React Native - Second API Call is not returning value

My problem is that my code is returning an undefined value because of my second API Call:
render(){
const result_postid = this.state.data_one.map(function(val) {
return val.postid;
}).join(',');
const result_spaceid = this.state.data_one.map(function(vall) {
return vall.spaceid;
}).join(',');
//These two will receive values.
const result_image = this.state.data_two.map(function(valll) {
return valll.image;
}).join(',');
//This last one somehow will not receive value
}
Here I am fetching two APIs in the same componentDidMount:
componentDidMount(){
//First API Call
fetch(`http://www.exmaple.com/React/data.php`, {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
},
}).then((response) => response.json())
.then((responseJson) => {
this.setState({
isLoading: false,
data_one: responseJson,
},function() {
});
}).catch((error) => {
console.error(error);
});
// Second API Call
fetch(`http://www.example.com/React/image_data.php`, {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
},
}).then((response) => response.json())
.then((responseJson) => {
this.setState({
data_two: responseJson,
},function() {
});
}).catch((error) => {
console.error(error);
});
}
To confirm that it wasn't just a data response issue, I deleted the first to const (result_postid) and (result_spaceid) and the error was gone (TypeError: undefined is not a function (evaluating 'this.state.data_two.map(function(valll){return valll.image}')). The data showed successfully, but I need all 3 const to return the value. Is there a way to return all values for all 3 const?
The API calls are asynchronous, when you use the values in the render function some of them do not exist until all the calls return. You should have an initial state in the constructor
constructor(props) {
super(props);
this.state = {
data_one: [],
data_two: []
}
}
That way the values are not undefined. When the API returns the value, then the setState will trigger the render again.
Also, why do you have an empty function in the setState in the callbacks?
It should be something like
this.setState({
data_two: responseJson,
});
A couple of recommendations:
Use camelCase for variable naming, _ is not an usual standard in JS
Move the API calls to a different file, that will help you keep the component more organized. Then from componentDidMount you just call the function to make the request.

Unhandled promise rejection Error: Cannot read property 'json' of undefined

answers.map((answer, index) => {
answer_text = answer.answer_text;
id = answer.id;
return fetch(BASE_URL + url, {
method: 'PUT',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
'Authorization': 'Token token=' + token
},
body: JSON.stringify({
question: {
answers_attributes: {
'0': {
answer_text: answer_text,
id: id
}
}
}
})
});
})
I used map function so that on every map it should go to JSON.stringify and assign the values. But I got error "Unhandled promise rejection TypeError: Cannot read property 'json' of undefined". please suggest me any solution.
Thanks in advance.
Here you are creating an array of fetch promises, we need more info about how you handle these promises after that, i suppose you're trying somewhere to get a response from these promises using .then(res => res.json()) but your server response is not in json format.
To handle a fetch promise rejection you need to do this:
fetch(smth)
.catch(error => //handle the error e.g. console.log(error))
To see if there's something wrong in your request json body you can log it server side or log it before sending, you can also log the server response, try this to identify what's wrong:
answers.map((answer, index) => {
answer_text = answer.answer_text;
id = answer.id;
const body = JSON.stringify({
question: {
answers_attributes: {
'0': {
answer_text: answer_text,
id: id
} }
}
})
console.log('Json body request :', body);
return fetch(BASE_URL + url, {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
'Authorization': 'Token token=' + token
},
body
}).then(res => {
console.log('server response :', res);
return res;
}).catch(err => console.log('Fetch error :', err));
})
I recommend using an app like Postman to test the responses from your api server (easier & faster to debug request/responses from an API)
Edit: I also think you want to do a POST request instead of PUT.

React-Native Fetch "POST" request throwing "SyntaxError: Unexpected end of JSON input" in Android

this is my function
don't know where is the problem
fetchData() {
fetch(REQUEST_URL, {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
},
body: JSON.stringify({
Request : 'menu',
active : '1',
})
}).then((response) => response.json())
.then((responseData) => {
this.setState({
menu: responseData.Response,
});
})
.catch((error) => {
console.warn('error',error);
})
.done();
}
please point out the problem in function
The error occcurs because your response cannot be casted to JSON format. This issue might happen because of wrong header, response body, or other various reasons based on your server. The way to go - since apparently the responses are not consistent - is to perform additional validation of server response before trying to cast the response to JSON.
You can do this by replacing:
.then((response) => response.json())
with
.then((response) => {
// In this case, we check the content-type of the response
if (response.headers.get('content-type').match(/application\/json/)) {
return response.json();
}
return response;
// You can also try "return response.text();"
})
The error will be occcurs because your response can not be casted to be JSON
format.
there are three type of php mysqli api formate
1 formData
2 xml
3 json
i think you are use Formdata api but you are request in json see formdata
example
1) json Request.. example
var Request = {
security:1,
token: token,
email: this.state.username,
password: this.state.password
};
console.log(JSON.stringify(Request));
fetch(API.login, {
method: "POST",
headers: {
Accept: "application/json",
"Content-Type": "application/json"
},
body: JSON.stringify(Request)
})
.then(res => res.json())
.then(res => {
console.log("Login RESPONCE::: ", res);
}
2)Formdata Example use form data i think your error will be solve
let formdata = new FormData()
formdata.append("Api variable",your post variable)
formdata.append("name",this.state.name)
formdata.append("email, this.state.email)
formdata.append("password",this.state.password)
fetch('http://192.168.1.116/Restaurants/Registration.php', {
method: 'POST',
headers: {
'Content-Type': 'multipart/form-data'
},
body:formdata
}).then(res => res.json())
.then(res => {
console.log('Data RESPONCE::', res);
}
then((response) => response.json())
^^^^^^^^^^^^^ I think this is the problem
Responses with status code not equal to 2xx will not go into catch when you use fetch API, therefore you may JSON.parse something such as a HTML page or plain text stream.
You should check if response.ok === true before you parse response as JSON.
The likely cause of this error is your server not returning something that's not valid JSON (likely not JSON at all, like a 404 page or similar).
If you set the request Content-Type to application/json, likely it will send a preflight request to check CORS.
In my React app (not React-Native), I got cross domain issue. My server doesn't support preflight request, and so the response looks like:
{
body: null,
status: 0,
ok: false,
}
which is causing response.json() failed even though I got the expected JSON response in Chrome Dev Tools.
In my case, I change request Content-Type to application/x-www-form-urlencoded which does not require a preflight request. It works as expected.
It might not help in your case but I hope it give you some insight.
Log responseData. It might be possible that API is returning invalid data.