So I'm new to AWS serverless architecture. I deployed my first lambda function using Claudia. I'm not sure whether I did it correctly. I deployed all the APIs to one lambda function using Claudia. The API endpoints works individually when I test it on Insomnia. But when I use it in my application only one specific API works and the lambda dies. For instance, I used this POST request to post some items and I have a useEffect in my React application which has a get request to retrieve all the items from the database. But once I post the item, nothing is returned. Could anyone help me understand what I'm doing wrong. P.S this is my final year project which is due in a few weeks. So, a quick answer would be appreciated.
Here is a sample code.
// Create a new Intake
router.post("/create", async (req, res) => {
const intake = req.body;
const { name, intakeCode, intakeYear } = req.body;
const checkIntake = await Intakes.findOne({
where: {
intakeCode: intakeCode,
},
});
if (checkIntake) {
res.json({ err: `An intake under ${intakeCode} already exists!` });
} else {
try {
await Intakes.create(intake);
res.json({ msg: `Successfully created ${name} ` });
} catch (e) {
if (e.name == "SequelizeDatabaseError") {
res.json({ err: "Year only accepts integer" });
} else {
res.json({ err: e.name });
}
}
}
});
// Find all Intakes
router.get("/findAll", async (req, res) => {
const listOfIntakes = await Intakes.findAll();
res.json(listOfIntakes);
});
Cheers
Looks like you are trying to build a Lambda function using JavaScript - but have encountered problems. I'm not familiar with Claudia. One suggestion that I have is to follow the official AWS SDK for JavaScript DEV Guide here:
https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/scheduled-events-invoking-lambda-example.html
That content will walk you through how to create a Lambda function using JS.
Related
This is a course quiz and this is the most basic information I need in order to create a React app. But while the endpoint URL is correct, the page "/products" returns a "400" error when I try to request the product list. The instructions I'm given are:
Obtain a list of products with
Route: /products
Body: Array
method: POST
{
"product-codes": [
"98798729",
"84876871",
"29879879",
]
}
My index.js
...
app.post(`/products`, async (req, res) => {
try {
const response = await axios.post(`${apiURL}/products`);
// console.log(response.data);
res.status(200).json(response.data);
} catch (error) {
res.status(400).json({ message: error.message });
}
});
in Postman
I use http://localhost:4000/products
and pass a Body / Raw /JSON:
{
"product-codes": [
"98798729",
"84876871",
"29879879",
]
}
But I can't get in! I am not seeing something obvious because this is the entry point to a very long and complex quiz. Thanks
What I see from the code is a recursive long call.
app.post(`/products`, async (req, res) => {
try {
const response = await axios.post(`${apiURL}/products`); // calling the same end point
// console.log(response.data);
res.status(200).json(response.data);
} catch (error) {
res.status(400).json({ message: error.message });
}
});
You should do something like this:
app.post(`/products`, async (req, res) => {
// do your logic
// when you pass body from postman on this endpoint
// you will receive the body here and save it to DB
// or do the manipulation and then send back the response
res.status(200).json(req.body.data);
});
I highly recommend you to first follow through some tutorials to understand how API works and how to create simple API using Node.js.
I am not sure what is happening. I had all the same code setup in dev using localhost and everything was working fine. I hosted my app to Vercel and my API to heroku and from what I can tell the API is working perfectly. The issue now is when I make a post request I get a 400 Bad Request error in the browser but it still makes the request and posts to my DB I have setup. Any help can be appreciated. I built this application in a MERN stack with NEXT.js
Here is my client side Post request
const postSubmit = async e => {
e.preventDefault();
try {
const { data } = await axios.post('/create-post', { content, image });
if(data.error) {
toast.error(data.error);
} else {
setPage(1);
newsFeed();
toast.success("Post created");
setContent('');
setImage({});
// socket.emit('new-post', data);
}
} catch(e) {
console.log(e);
}
}
Here is my server side handling of the post request
export const createPost = async (req, res) => {
const { content, image } = req.body;
if(!content.length) {
return res.json({
error: 'Content is required'
})
}
try {
const post = new Post({ content, image, postedBy: req.user._id });
await post.save();
const postWithUser = await Post.findById(post._id).populate('postedBy', '-password -secret');
res.json(postWithUser);
} catch (e) {
console.log(e);
res.sendStatus(400);
}
};
And here is what the browser is telling me
Chrome Browser Info
This is most likely caused by a typo on the MongoDB connection string (URI), similar to this answer.
In the linked answer, the typo was the semi-colon in &w=majority;. In your case, the value is somehow majorityDATABASE=, so double-check your MongoDB connection string and try to remove the extra DATABASE= in the write concern parameter.
It's likely that the await Post.findById() call is not finding a result which could be throwing an error when you try to call res.json(postWihUser). That would then cause an error when postWithUser is not defined.
What is logged to the server's terminal when an error occurs? That should help you identify the problem.
I am working on API Get request. I have created a POST request to add the data in firebase realtime database. The code is as follows:
// CREATE POST
app.post("/post", (req, res) => {
let key;
firebase.auth().onAuthStateChanged((user) => {
if (user) {
// User is signed in.
var newPost = firebase.database().ref("posts/");
var myPost = newPost.push({
createdBy: user.uid,
from: req.body.from,
to: req.body.to,
duration: req.body.duration,
comments: req.body.comments,
});
res.send(newPost);
const postId = myPost.key;
console.log(postId);
} else {
// No user is signed in.
res.status(404).send("No user is signed in right now!");
}
});
});
Now, in order to get a specific post, I have written the following code:
// GET SPECIFIC POST
app.get("/post/:id", (req, res) => {
let response;
firebase
.database()
.ref("posts/" + req.params.id)
.on("value", (snapshot) => {
response = snapshot.val();
});
res.send(response);
});
I am new at Firebase, so I dont really know how to get a specific post. Please help me out
Calls to Firebase are asynchronous, because they require a call to the server. While that call is happening, your main code continues. And then when the data is available, your callback is invoked with the data from the server.
Right now your res.send(response) runs before the response = snapshot.val() is ever called. The rule with asynchronous APIs is simple: any code that needs the data needs to be inside the callback, or be called from there.
So in your case:
app.get("/post/:id", (req, res) => {
firebase
.database()
.ref("posts/" + req.params.id)
.once("value")
.then((snapshot) => {
res.send(snapshot.val());
});
});
You'll note that I also change from on to once, since you only care about getting the value once (instead of attaching a permanent listener that monitors the database for changes).
Dealing with asynchronous API is a common stumbling block, so I recommend spending some time reading these answers to learn more:
Why Does Firebase Lose Reference outside the once() Function?
Firebase response is too slow
Best way to retrieve Firebase data and return it, or an alternative way
I simply did this:
app.get("/post/:id", (req, res) => {
var key = req.params.id;
console.log(key);
firebase
.database()
.ref("posts")
.child(key)
.get()
.then((snapshot) => {
res.send(snapshot.val());
});
});
this solved the problem
I have successfully created an api that stores books on heroku with express and postgresql following this tutorial https://www.taniarascia.com/node-express-postgresql-heroku/ witch everything works fine but I tried to follow the front-end part but it doesn't work.
Here is the api here https://node-api-with-books.herokuapp.com/books
Any help would be appreciated and it would help me if you used the tutorial to help.
Based on the tutorial you would need an async function to call the api from a front end.
async function getBooks() {
try {
const response = await fetch("https://node-api-with-books.herokuapp.com/books");
return await response.json();
// console.log(books)
} catch (error) {
console.log("Error", error);
}
}
getBooks().then(book => {
console.log(book);
});
Check the console in Stackblitz - https://stackblitz.com/edit/js-9dmngb?file=index.js
I am currently working on a web app to manage an external database. I am not very familiar with express or NodeJS at this point so I wanted to ask how to send a JSON object to the client sides console without getting undefined?
I have this function to connect then select the what I need and afterwards I converted my JSON object to an array of JSON objects. It displays the data fine in the console as well.
async function connect() {
try {
await sequelize.authenticate();
console.log('Connection has been established successfully.');
} catch (err) {
console.error('Unable to connect to the database:', error);
}
info = await sequelize.query('select * from LeadsInformation', { type: QueryTypes.SELECT });
const details = JSON.stringify(info);
console.log(details);
detailsArray = JSON.parse(details);
console.log(detailsArray);
}
Everything works fine in here, I can get the data and display it in the terminal.
This is my GET route:
app.get("/list", (req, res) => {
connect();
res.json(detailsArray)
});
I have tried a couple of suggested ways based on other explanations and code snippets but none of them has worked so far so I left it like that. I thought foreaching through the data itself in the request would be a solution but it did not work. I also tried using the JSON itself and trying to display it and also tried using the body parser library. Though the library has not been updated for two years. Also I am using axios to fetch the data. It works fine when I try sending a simple string like "hello world" for example.
Is there anything that I'm missing or do you have any other solutions? I would also appreciate an explanation as well if possible.
Edit: It might also have to do something with how I am getting the response in the frontend. I'll look into that as well and will update this thread if I sort it out!
This is the way I get the response. I am currently trying to show in the console. I am using axios API.
Axios({
method: "GET",
url: "http://localhost:5000/list",
headers: {
"Content-Type": "application/json"
}
}).then(res => {
console.log(res.data.json);
});
Probably you have undefined in route because connect function doesn't return anything.
Also connect is an async function it means that it returns Promise and you have to call .then method or use await to get value from it.
Here is the code snippet with fixes that I described above.
async function connect() {
try {
await sequelize.authenticate();
console.log('Connection has been established successfully.');
} catch (err) {
console.error('Unable to connect to the database:', error);
}
info = await sequelize.query('select * from LeadsInformation', { type: QueryTypes.SELECT });
const details = JSON.stringify(info);
detailsArray = JSON.parse(details);
return detailsArray;
}
app.get("/list", async (req, res) => {
const result = await connect();
res.json(result)
});
Notice that in the router handler function I also use async and await because I call connect which is an asynchronous function.
The solution above did work and also another problem I had was that I wasn't getting the response correctly.
I ended up getting the response to the frontend after changing my code to the following from:
console.log(res.data.json);
To:
console.log(res.data[1]);