I'm testing to send custom headers when creating a remote database with PouchDB. The fact is that according to the documentation the way to proceed is as follows (https://pouchdb.com/api.html):
var db = new PouchDB('http://example.com/dbname', {
fetch: function (url, opts) {
opts.headers.set('X-Some-Special-Header', 'foo');
return PouchDB.fetch(url, opts);
}
});
My code is almost copied and pasted
const db = new PouchDB(this.server, {
fetch(url, opts) {
opts.headers.set('xx-custom-xx', this.text);
opts.credentials = 'include';
return PouchDB.fetch(url, opts);
}
});
When I try to launch it I get two errors:
Error1: "export 'fetch' (imported as 'PouchDB') was not found in 'pouchdb' (possible exports: default)" This error is being given by the line"return PouchDB.fetch(url, opts); "
Error2: "set does not exist on type headersinit"
I hope someone can help me. Thanks.
I get it.. the problem are two.
First, I was importing Pouch like this
import * as PouchDB from 'pouchdb';
I have notice in other project I imported it by
import PouchDB from 'pouchdb';
In my new project with import PouchDB from 'pouchdb'; didn't work because I didn't set "allowSyntheticDefaultImports":true flag in tsconfig
AllowSyntheticDefaultImports flag is specified in doc but It does't work (no for me) with import * as PouchDB from 'pouchdb';
Related
I have been trying to make custom component in Adminjs 6.6.5 dashboard but Adminjs ComponentLoader not found error occurs. then i have tried to
import AdminJS from 'adminjs'
const {ComponentLoader} = AdminJS
but i get: Trying to bundle file 'file:/Users/Josip/WebstormProjects/ferry-backend/components/dashboard.jsx' but it doesn't exist
I would really appreciate help...
admin/index.js
import {ComponentLoader} from "adminjs";
const componentLoader = new ComponentLoader()
const Components = {
MyDashboard: componentLoader.override('Dashboard','../components/dashboard.jsx')
}
export { componentLoader, Components }
index.js
import {componentLoader, Components} from "./admin/index.js";
AdminJS.registerAdapter(AdminJSSequelize)
const admin = new AdminJS({
databases: [],
rootPath: '/admin',
resources:[UsersResources, GuestResources, SalesResources, FinancesResources],
components:{
edit: Components.MyDashboard
},
componentLoader
})
you are fixed this problem? I also ran into this problem and don't understand how to solve it
i fixed this problem. You need to do the import as follows
import AdminJs from 'adminjs';
// And now you can use any adminjs dependencies as follows
AdminJs.ValidationError(errors)
My usage example:
if(Object.keys(errors).length) {throw new AdminJs.ValidationError(errors)} else {...}
Good luck with your development!
I am creating an application in Svelte Sapper. I have a routes/account/login.js API route where I am trying to use mysql2. The route itself works (I checked with Postman), but as soon as I import mysql, the server crashes and an error appears:
[rollup-plugin-svelte] The following packages did not export their `package.json` file so we could not check the "svelte" field. If you had difficulties importing svelte components from a package, then please contact the author and ask them to export the package.json file.
- mysql2
import mysql from "mysql2/promise";
export async function post(req, res) {
//route test
const { login, password } = req.body;
res.end(`${login}, ${password}`);
}
What can I do to make this import work?
What can I do to make this import work?
The Sapper documentation doesn't say anything about whether you need to change something in the configuration additionally. https://sapper.svelte.dev/docs#Server_routes
I found a solution. I had to create a #lib folder in the src/node_modules folder and there file eg. db.js. In that file instead of import you need to use require()! and then you have to export the function that connects to the database. and then you can import that in the path
//src/node_modules/#lib/db.js
const mysql = require("mysql2");
export async function connectToDatabase() {
return mysql.createConnection({
host: "localhost",
....
})
}
//routes/account/login.js
import { query } from "#lib/db";
export async function post(req, res) {
...
}
I'm using Next.js for my side project. I have a PostrgeSQL database hosted on ElephantSQL. Inside the Next.js project, I have a GraphQL API set up, using the apollo-server-micro package.
Inside the file where the GraphQL API is set up (/api/graphql), I import a database helper-module. Inside that, I set up a pool connection and export a function which uses a client from the pool to execute a query and return the result. This looks something like this:
// import node-postgres module
import { Pool } from 'pg'
// set up pool connection using environment variables with a maximum of three active clients at a time
const pool = new Pool({ max: 3 })
// query function which uses next available client to execute a single query and return results on success
export async function queryPool(query) {
let payload
// checkout a client
try {
// try executing queries
const res = await pool.query(query)
payload = res.rows
} catch (e) {
console.error(e)
}
return payload
}
The problem I'm running into, is that it appears as though the Next.js API doesn't (always) keep the connection alive but rather opens up a new one (either for every connected user or maybe even for every API query), which results in the database quickly running out of connections.
I believe that what I'm trying to achieve is possible for example in AWS Lambda (by setting context.callbackWaitsForEmptyEventLoop to false).
It is very possible that I don't have a proper understanding of how serverless functions work and this might not be possible at all but maybe someone can suggest me a solution.
I have found a package called serverless-postgres and I wonder if that might be able to solve it but I'd prefer to use the node-postgres package instead as it has much better documentation. Another option would probably be to move away from the integrated API functionality entirely and build a dedicated backend-server, which maintains the database connection but obviously this would be a last resort.
I haven't stress-tested this yet, but it appears that the mongodb next.js example, solves this problem by attaching the database connection to global in a helper function. The important bit in their example is here.
Since the pg connection is a bit more abstract than mongodb, it appears this approach just takes a few lines for us pg enthusiasts:
// eg, lib/db.js
const { Pool } = require("pg");
if (!global.db) {
global.db = { pool: null };
}
export function connectToDatabase() {
if (!global.db.pool) {
console.log("No pool available, creating new pool.");
global.db.pool = new Pool();
}
return global.db;
}
then in, eg, our API route, we can just:
// eg, pages/api/now
export default async (req, res) => {
const { pool } = connectToDatabase();
try {
const time = (await pool.query("SELECT NOW()")).rows[0].now;
res.end(`time: ${time}`);
} catch (e) {
console.error(e);
res.status(500).end("Error");
}
};
I have a react app running redux and thunk which has all been working fine. I need to persist the store state on page reload so that data is not lost, so have created a function which is storing data in the localstorage and then returning the data ready for adding to createStore (https://stackoverflow.com/a/45857898/801861). The data storage is working fine and returning the object ready for setting the sate. When adding the data object at createStore react fails to compile with this error:
Error: It looks like you are passing several store enhancers to createStore(). This is not supported. Instead, compose them together to a single function
Here is CURRENT CODE RETURNING ERROR:
const store = createStore(reducers, LoadState, applyMiddleware(thunk) );
//Error: It looks like you are passing several store enhancers to createStore(). This is not supported. Instead, compose them together to a single function
My original code which was running:
const store = createStore(reducers, applyMiddleware(thunk) );
I attempted to fix this following some similar issues I found online, compiles but breaks site code which was originally working fine:
const composeEnhancers = LoadState || compose;
const store = createStore(reducers, composeEnhancers( applyMiddleware(thunk) ) );
//Error: Actions must be plain objects. Use custom middleware for async actions.
Not sure what I need to change to get this to work, any help is appreciated.
I think you are following a tutorial which is performing tasks in a previous version of redux.
You need to create a composeEnhancer which will take in your Redux Dev Tools extension as shown
const composeEnhancer = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
after importing compose from 'redux' obviously as shown -
import {createStore, compose, applyMiddleware} from 'redux';
and then, you can create the store as shown -
const Store = createStore(rootReducer, composeEnhancer(applyMiddleware(thunk)))
The error is self-explanatory. It tells you what to do exactly!!
Namely it tell you that you should compose your enhancers instead.
Here is how to it:
Step #1: Import 'compose' from redux library
import { createStore, applyMiddleware, compose } from 'redux';
Step #2: Compose your list of enhancers since you have more than one
const enhancers = [LoadState, applyMiddleware(thunk)];
const store = createStore(
reducers,
compose(...enhancers)
);
Refer to this page for more details.
I suspect your issue is within your LoadState. What ever is it? Here is a working createStore:
const store = createStore(
reducers,
{ counter: { count: 5 } },
applyMiddleware(() => dispatch => {
console.log('Yoyoyo')
return dispatch;
}));
Hope it solves your issue. Make sure to put actual initial state values and not some function or what ever it is LoadState is :)
You can use a package to persist the redux store into the local storage and you don't need to make your own function:
https://github.com/rt2zz/redux-persist
In the first example of the package you can see how to use the persistReducer() and persistStore() to save your state and then auto rehydrates on refresh page.
plz check this advanced store setup that may help you
enter link description here
https://github.com/zalmoxisus/redux-devtools-extension#12-advanced-store-setup
import { createStore, applyMiddleware, compose } from 'redux';
+ const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
+ const store = createStore(reducer, /* preloadedState, */ composeEnhancers(
- const store = createStore(reducer, /* preloadedState, */ compose(
applyMiddleware(...middleware)
));
Am starting out with it React-Redux and faced the same issue. am not sure if it is the right approach but here we go.
the one issue you only need to fix in your code is to call the function,
store = createStore(reducers, LoadState(), applyMiddleware(thunk) );
this solution worked for me.
For redux saga users,
import createSagaMiddleware from "redux-saga";
const sagaMiddleware = createSagaMiddleware();
const composeEnhancer = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
const store = createStore(rootReducer, composeEnhancer(applyMiddleware(sagaMiddleware)))
import { applyMiddleware, compose, createStore } from "redux";
import { devToolsEnhancer } from "redux-devtools-extension";
import { logger } from "./middlewares/logger";
import reducers from "./reducers";
import { todoReducer } from "./todoReducer";
const store = createStore(
reducers,
compose(applyMiddleware(logger), devToolsEnhancer({ trace: true }))
);
export default store;
I have a strange problem with my application. I get an error, and I can't solve it. First at all, I installed a new project, so everything is clean. Someone sent me this repo to use for an Angular, Electron and Nodejs Application. Everything worked fine, but then I decided to install an embedded database like sqlite3. For this I found NeDB, and the module is perfect for my needs. First I had the problem, has nothing to do with my general problem, that I can't create a database file. So I read that I can only create files in my application path, because something about Electron and that's working in a browser.
I found the getAppPath() method that is implemented in my app object from the Electron module. Here starts the problem. For hours I tried to get the application path from this object. Finally, I wrote this code.
import { Injectable } from '#angular/core';
var nedb = require('nedb');
import { app } from 'electron';
import * as path from 'path';
#Injectable()
export class DatabaseService {
app: typeof app;
Database: any;
constructor() {
this.app = window.require("electron").app;
this.Database = new nedb({ filename: path.join(this.app.getAppPath(), '/diary.db'), autoload: true, timestampData: true });
var scott = {
name: 'Scott',
twitter: '#ScottWRobinson'
};
this.Database.insert(scott, function(err, doc) {
console.log('Inserted', doc.name, 'with ID', doc._id);
});
}
}
And I get this error.
I found this posting, but I don't really understand what the post is trying to tell me. I followed the links, but nothing seems to help. Anyone have an idea?