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Ethers.js: ReferenceError: utils is not defined

I'm trying to create a listener for incoming transactions with ethers.js (v5.6). According to the docs, to listen to incoming transactions you need to create this filter:
// List all token transfers *to* myAddress:
filter = {
address: tokenAddress,
topics: [
utils.id("Transfer(address,address,uint256)"),
null,
hexZeroPad(myAddress, 32)
]
};
Having this in my script gives me an error saying utils.id("Transfer(address,address,uint256)"), ReferenceError: utils is not defined. I can't find anything in the docs about importing an utils package. Can anyone sort me out?
My full code:
async function incomingTransactions() {
if (loadedUser) {
console.log("User loaded", loadedUser)
let myAddress = loadedUser.publicKey
let filter = {
address: myAddress,
topics: [
utils.id("Transfer(address,address,uint256)"),
null,
hexZeroPad(myAddress, 32)
]
};
// let foo = await provider.getLogs(filter)
// console.log(foo)
}
console.log("No user loaded")
}
const interval = setInterval(function() {
incomingTransactions();
}, 5000);

Looks like utils is part of the ethers object, and hexZeroPad and id are part of utils so you can use them like so:
const { ethers } = require("ethers"); // assuming commonjs
ethers.utils.id("Transfer(address,address,uint256)");
ethers.utils.hexZeroPad(myAddress, 32);

How to create pages from non-seriazable data(functions)

I have this JavaScript data file(src/test/test.js):
module.exports = {
"title": "...",
"Number": "number1",
"Number2": ({ number1 }) => number1 / 2,
}
I want to pass this file verbatim(functions preserved) to a page, so that the page can use that data to build itself. I already have the page template and everything else sorted out, I just need to find a way to pass this into the page.
The first approach I tried is requireing this file in gatsby-node.js and then passing it as pageContext.
gatsby-node.js
const path = require('path');
exports.createPages = ({actions, graphql}) => {
const { createPage } = actions;
return graphql(`
query loadQuery {
allFile(filter: {sourceInstanceName: {eq: "test"}}) {
edges {
node {
relativePath
absolutePath
}
}
}
}
`).then(result => {
if (result.errors) {
throw result.errors;
}
for (const node of result.data.allFile.edges.map(e => e.node)) {
const data = require(node.absolutePath);
createPage({
path: node.relativePath,
component: path.resolve('./src/templates/test.js'),
context: data,
});
}
});
};
gatsby-config.js
module.exports = {
plugins: [
{
resolve: `gatsby-source-filesystem`,
options: {
name: `test`,
path: `${__dirname}/src/test/`,
},
},
],
}
src/templates/test.js
import React from 'react';
const index = ({ pageContext }) => (
<p>{pageContext.Number2()}</p>
);
export default index;
However, I get this warning when running the dev server:
warn Error persisting state: ({ number1 }) => number1 / 2 could not be cloned.
If I ignore it and try to use the function anyway, Gatsby crashes with this error:
WebpackError: TypeError: pageContext.Number2 is not a function
After searching for a while, I found this:
The pageContext was always serialized so it never worked to pass a function and hence this isn't a bug. We might have not failed before though.
- Gatsby#23675
which told me this approach wouldn't work.
How could I pass this data into a page? I've considered JSON instead, however, JSON can't contain functions.
I've also tried finding a way to register a JSX object directly, however I couldn't find a way.

Regarding the main topic, as you spotted, can't be done that way because the data is serialized.
How could I pass this data into a page? I've considered JSON instead,
however, JSON can't contain functions.
Well, this is partially true. You can always do something like:
{"function":{"arguments":"a,b,c","body":"return a*b+c;"}}
And then:
let func = new Function(function.arguments, function.body);
In this case, you are (de)serializing a JSON function, creating and casting a function based on JSON parameters. This approach may work in your scenario.
Regarding the JSX, I guess you can try something like:
for (const node of result.data.allFile.edges.map(e => e.node)) {
const data = require(node.absolutePath);
createPage({
path: node.relativePath,
component: path.resolve('./src/templates/test.js'),
context:{
someComponent: () => <h1>Hi!</h1>
},
});
}
And then:
import React from 'react';
const Index = ({ pageContext: { someComponent: SomeComponent} }) => (
return <div><SomeComponent /></div>
);
export default index;
Note: I don't know if it's a typo from the question but index should be capitalized as Index
In this case, you are aliasing the someComponent as SomeComponent, which is a valid React component.

Extra semicolon showing up in axios get request

I am trying to dynamically build an axios get request, and have currently hardcoded some values in my parameters array to test with like so:
const parameters = [
'table=cumulative',
'where=koi_disposition like \'CANDIDATE\' and koi_period>300 and koi_prad<2',
'order=koi_period',
'format=json'
];
let searchParameters = '';
const api = axios.create({
baseURL: 'https://exoplanetarchive.ipac.caltech.edu/cgi-bin/nstedAPI/nph-nstedAPI'
});
for (let element in parameters) {
if (element !== '') {
searchParameters += `?${parameters[element]}`;
}
}
I then add this query to my axios get request below:
export const getExoplanets = async () => {
try {
searchParameters = searchParameters.replace(/;/g, "");
console.log(`${searchParameters}`);
return await api.get(`${searchParameters}`);
// return await api.get(`?table=cumulative&where=koi_disposition like 'CANDIDATE' and koi_period>300 and koi_prad<2&order=koi_period&format=json`);
} catch (error) {
return error;
}
};
When the variable version runs the api returns the error:
ERROR
Error Type: UserError
Message: Constraint contains an illegal keyword: ";"
However when the commented out, hard coded version runs it works just fine. At some point an extra semicolon is being added to the request. I assume it is being added at the end, but I can't find where or how. Any ideas how to fix this?

Axios supports easy query parameters using the params config option.
Just provide an object of key / value pairs and Axios will do all the encoding for you
const params = {
table: "cumulative",
where: "koi_disposition like 'CANDIDATE' and koi_period>300 and koi_prad<2",
order: "koi_period",
format: "json"
}
return api.get("", { params })
// or return api.get("", { params: params })
This will send a request to
?table=cumulative&where=koi_disposition+like+%27CANDIDATE%27+and+koi_period%3E300+and+koi_prad%3C2&order=koi_period&format=json

it seem you having an issue in this bellow line you have used the \ rest of this you can wrap all the things in the double quote.
'where=koi_disposition like \'CANDIDATE\' and koi_period>300 and koi_prad<2',
"where=koi_disposition like 'CANDIDATE' and koi_period>300 and koi_prad<2",

convert a string to JSON object array- NOdejs

Lets presume I am sending a POST request to /api/products. My body is like below
{
"products":[
{
"id":"5f5065e44a12bd00232bcc6g",
"status":"true"
},
{
"id":"5f5065e44a12bd00232bcc6g",
"status":"true"
}
]
}
In my route I am trying to convert the above products to a JSON Object;
Below is my server code
const { products } = req.body;
console.log(JSON.parse(products));
but this gives me the error "message": "Something went wrong Unexpected token o in JSON at position 1"
How can i achieve this??
Cheers
Screenshots added
Tried below as well. But no luck
Nothing works.
const products = req.body;
console.dir(typeof products); // 'object'
console.dir(products); // { products: '[object Object]' }
const { products } = req.body;
console.dir(typeof products); // 'string'
console.dir(products); // '[object Object]'
postman developer console is as below. Doesnt seem to be an issue
{
"products":[
{
"id":"5f5065e44a12bd00232bcc6g",
"status":"true"
},
{
"id":"5f5065e44a12bd00232bcc6g",
"status":"true"
}
]
}

It's not a JSON object, JSON objects are surrounded by curly braces.
if you return
{"products": [ { "id":"5f5065e44a12bd00232bcc6g", "status":"true" }, { "id":"5f5065e44a12bd00232bcc6g", "status":"true" } ]}
then it will be worked.

The best thing to do would be to fix what you're sending to /api/products by putting {} around it, like this:
{
"products":[
{
"id":"5f5065e44a12bd00232bcc6g",
"status":"true"
},
{
"id":"5f5065e44a12bd00232bcc6g",
"status":"true"
}
]
}
Now it's valid JSON, and you can convert it via JSON.parse:
const obj = JSON.parse(req.body);
console.log(obj);
const { products } = obj;
or just
const { products } = JSON.parse(req.body);
Notice I'm using the entire body there. That will give you an object with a property (products) with the array of products. Alternatively, instead of parsing it manually, you could use middleware that would parse it automatically so that req.body is the parsed result, in which case it's just:
console.log(req.body);
const { products } = req.body;
If for some reason you can't send correct JSON, but it will always be in the form you've shown, you could add the {} afterward like this:
const obj = JSON.parse("{" + req.body + "}");
console.log(obj);
const { products } = obj;
or just
const { products } = JSON.parse("{" + req.body + "}");
but I strongly recommend not doing that, not least because you can't use middleware and sending malformed data around tends not to be ideal. Instead, send valid JSON in the first place.

Look at the content of your variable products, and your debugger.
In this line you're using an object destructuring assignment but the right hand side isn't an object, it's a string:
const { products } = req.body;
Try this instead:
const { products } = JSON.parse(req.body);
EDIT you appear to be using Express middleware or similar. There's a good chance that your object has already been converted from JSON so you just need your original line and not the JSON.parse line.
const { products } = req.body;
console.dir(products);

Figured it out.
Thanks to #T.j and #Alnitak was able to get this sorted. Used
let obj = req.body;
But i had an issue with my validator.
body('products')
.trim()
.not()
.isEmpty()
.withMessage('Custom product must have a main product'),
In the above code using .trim() converted the products into a string and once I removed the trim() it works perectly. Thanks all for the thoughts

Try with JSON.stringify()
Otherwise, maybe you were declaring an object (const { products }), try without the {}

Working gremlin javascript example

There is a new version out, but the documentation is somewhat lacking a working example.
Github Ticket: https://github.com/jbmusso/gremlin-javascript/issues/109
I've been trying to get an example to work. Any help appreciated:
gremlin-server: 3.3.2 with config gremlin-server-modern.yaml
npm gremlin lib: 3.3.2
import gremlin from 'gremlin';
import DriverRemoteConnection from 'gremlin/lib/driver/driver-remote-connection';
import { Graph } from 'gremlin/lib/structure/graph';
const graph = new Graph()
const g = graph.traversal().withRemote(new DriverRemoteConnection('ws://localhost:8182/gremlin', { mimeType: 'application/vnd.gremlin-v3.0+json' }));
const fetchById = async (id) => {
const result = await g.V(id).toList()
console.log(result);
}
const addUser = async (name) => {
const newVertex = await g.addV().property('name','marko').property('name','marko a. rodriguez').next()
console.log(newVertex)
}
addUser()
fetchById(0)
Current Output:
[]
{ value: null, done: true }

UPDATE
Gremlin JavaScript now supports GraphSON3 and the latest Gremlin Server.
Working example:
const gremlin = require('gremlin');
const Graph = gremlin.structure.Graph;
const DriverRemoteConnection = gremlin.driver.DriverRemoteConnection;
Obtain a traversal source (g):
const graph = new Graph();
const connection = new DriverRemoteConnection('ws://localhost:8182/gremlin');
const g = graph.traversal().withRemote(connection);
Once you have a traversal source (g), reuse it across your application to create traversals, for example:
// Get the friends' names
const friends = await g.V().has("name","Matt")
.out("knows").values("name").toList();
See more information on the documentation: https://tinkerpop.apache.org/docs/current/reference/#gremlin-javascript
ORIGINAL ANSWER
Gremlin JavaScript doesn't support GraphSON3 serialization, which is the default in TinkerPop 3.3+. This causes your response to not be properly parsed.
I've filed a ticket to support GraphSON3 in the JavaScript GLV: https://issues.apache.org/jira/browse/TINKERPOP-1943
In the meantime, as a workaround, you can add GraphSON2 serializers to the server by adding the following line to your yaml, below serializers:
- { className: org.apache.tinkerpop.gremlin.driver.ser.GraphSONMessageSerializerGremlinV2d0, config: { ioRegistries: [org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerIoRegistryV2d0] }}

Regarding the read property 'reader' of undefined issue. I falled back to version gremlin#3.3.4 and it works fine.