is there a way to get data from a database in postgres using wasm?. I'd tried to get it using a library in rust but I got some errore when I build the package using "wasm-pack building--target web". The idea is to build a function in lib.rs file that return data from a db. I have the below code inside lib.rs:
use postgres::{Client, Error, NoTls};
use wasm_bindgen::prelude::*;
...
struct Author {
_id: i32,
name: String,
}
#[wasm_bindgen]
pub fn select_name(name: &String) -> Result<(), Error> {
let mut client = Client::connect("postgresql://user:1234#localhost:5432/db", NoTls)?;
for row in client.query(
"SELECT id, name FROM author WHERE name = $1",
&[&name],
)? {
let author = Author {
_id: row.get(0),
name: row.get(1),
};
println!(
"Select_Name => Author {} :",
author.name
);
}
Ok(())
}
but I get some errors:
error[E0432]: unresolved import `crate::sys::IoSourceState`
error[E0432]: unresolved import `crate::sys`
...
It is not possible directly (as Njuguna Mureithi rightly wrote) but it can be circumvented.
We can use the project: https://github.com/PostgREST/postgrest
and expose the API to our sql server.
We download the latest version of postgrest
https://github.com/PostgREST/postgrest/releases/tag/v9.0.0
in case of Linux we unpack
tar -xf postgrest-v9.0.0-linux-static-x64.tar.xz
then run help
./postgrest -h
create a configuration file for ./postgrest
postgrest -e > cfg.psqlrest
change the user and password for the database in the configuration file.
e.g. with
db-uri = "postgres://user:pasword#localhost:5432/dbname"
to your dbname database access user:pasword configuration
db-uri = "postgres://postgres:zaqwsxc#localhost:5432/dbname"
and run the server which will issue the api to our postgres
./postgrest cfg.psqlrest
The address http://localhost:3000 will start accessing the database dbname, which must be created in the database server beforehand.
Here is a description of the libraries needed to call the query using the API.
https://rustwasm.github.io/wasm-bindgen/examples/fetch.html
examples of API
https://postgrest.org/en/stable/api.html
So
Console:
yarn dev
yarn run v1.22.10
$ nodemon dist/index.js
[nodemon] 2.0.7
[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): *.*
[nodemon] watching extensions: js,mjs,json
[nodemon] starting `node dist/index.js`
[discovery] ORM entity discovery started, using ReflectMetadataProvider
[discovery] - processing entity Post
[discovery] - entity discovery finished, found 1 entities, took 21 ms
[info] MikroORM successfully connected to database postgres on postgresql://postgres:*****#127.0.0.1:5432
[query] begin
[query] insert into "post" ("created_at", "title", "updated_at") values ('2021-04-05T21:04:23.126Z', 'my first post', '2021-04-05T21:04:23.126Z') returning "_id" [took 12 ms]
[query] rollback
TableNotFoundException: insert into "post" ("created_at", "title", "updated_at") values ('2021-04-05T21:04:23.126Z', 'my first post', '2021-04-05T21:04:23.126Z') returning "_id" - relation "post" does not exist
at PostgreSqlExceptionConverter.convertException (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\postgresql\PostgreSqlExceptionConverter.js:36:24)
at PostgreSqlDriver.convertException (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\drivers\DatabaseDriver.js:194:54)
at P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\drivers\DatabaseDriver.js:198:24
at processTicksAndRejections (internal/process/task_queues.js:93:5)
at async PostgreSqlDriver.nativeInsert (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\knex\AbstractSqlDriver.js:150:21)
at async ChangeSetPersister.persistNewEntity (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\unit-of-work\ChangeSetPersister.js:55:21)
at async ChangeSetPersister.executeInserts (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\unit-of-work\ChangeSetPersister.js:24:13)
at async UnitOfWork.commitCreateChangeSets (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\unit-of-work\UnitOfWork.js:496:9)
at async UnitOfWork.persistToDatabase (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\unit-of-work\UnitOfWork.js:458:13)
at async PostgreSqlConnection.transactional (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\knex\AbstractSqlConnection.js:53:25)
at async UnitOfWork.commit (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\unit-of-work\UnitOfWork.js:183:17)
at async SqlEntityManager.flush (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\EntityManager.js:486:9)
at async SqlEntityManager.persistAndFlush (P:\.Projektek\lireddit-server\node_modules\#mikro-orm\core\EntityManager.js:438:9)
previous error: insert into "post" ("created_at", "title", "updated_at") values ('2021-04-05T21:04:23.126Z', 'my
first post', '2021-04-05T21:04:23.126Z') returning "_id" - relation "post" does not exist
at Parser.parseErrorMessage (P:\.Projektek\lireddit-server\node_modules\pg-protocol\dist\parser.js:278:15)
at Parser.handlePacket (P:\.Projektek\lireddit-server\node_modules\pg-protocol\dist\parser.js:126:29)
at Parser.parse (P:\.Projektek\lireddit-server\node_modules\pg-protocol\dist\parser.js:39:38)
at Socket.<anonymous> (P:\.Projektek\lireddit-server\node_modules\pg-protocol\dist\index.js:10:42)
at Socket.emit (events.js:315:20)
at Socket.EventEmitter.emit (domain.js:467:12)
at addChunk (internal/streams/readable.js:309:12)
at readableAddChunk (internal/streams/readable.js:284:9)
at Socket.Readable.push (internal/streams/readable.js:223:10)
at TCP.onStreamRead (internal/stream_base_commons.js:188:23) {
length: 166,
severity: 'ERROR',
code: '42P01',
detail: undefined,
hint: undefined,
position: '13',
internalPosition: undefined,
internalQuery: undefined,
where: undefined,
schema: undefined,
table: undefined,
column: undefined,
dataType: undefined,
constraint: undefined,
file: 'd:\\pginstaller_13.auto\\postgres.windows-x64\\src\\backend\\parser\\parse_relation.c',
line: '1376',
routine: 'parserOpenTable'
}
Index.ts:
import { MikroORM } from "#mikro-orm/core";
import { __prod__ } from "./constants";
import { Post } from "./entities/Post";
import mikroConfig from "./mikro-orm.config";
const main = async () => {
const orm = await MikroORM.init(mikroConfig);
await orm.getMigrator().up;
const post = orm.em.create(Post, { title: "my first post" });
await orm.em.persistAndFlush(post);
};
main().catch((err) => {
console.error(err);
});
Post.ts:
import { Entity, PrimaryKey, Property } from "#mikro-orm/core";
#Entity()
export class Post {
#PrimaryKey()
_id!: number;
#Property({ type: "date" })
createdAt = new Date();
#Property({ type: "date", onUpdate: () => new Date() })
updatedAt = new Date();
#Property({ type: "text" })
title!: string;
}
mikro-orm.config.ts:
import { __prod__ } from "./constants";
import { Post } from "./entities/Post";
import { MikroORM } from "#mikro-orm/core";
import path from "path";
export default {
migrations: {
path: path.join(__dirname, "./migrations"),
pattern: /^[\w-]+\d+\.[tj]s$/,
},
entities: [Post],
dbName: "postgres",
debug: !__prod__,
type: "postgresql",
password: "hellothere",
} as Parameters<typeof MikroORM.init>[0];
And the migration I created with npx mikro-orm migration:create:
import { Migration } from '#mikro-orm/migrations';
export class Migration20210405205411 extends Migration {
async up(): Promise<void> {
this.addSql('create table "post" ("_id" serial primary key, "created_at" timestamptz(0) not null, "updated_at" timestamptz(0) not null, "title" text not null);');
}
}
After that im compiling it to js btw, but I guess the problem will be somewhere at my code or idk plz help me, I can give you more info just plz help, I've been trying to fix this bug for 5 hours :/
Btw Im doin Ben Awad's 14 hour fullstack tutorial if its matter.
The TableNotFoundException happens when you try to add data before initializing the table's schema (or structure).
Passing the --initial as in Mosh's Answer did not work for me, possibly because I am passing a username and password in ./mikro-orm.config.ts.
I used Mikro-ORM's SchemaGenerator to initialize the table as seen here in the official docs.
Add the following lines before adding data to post in your main function in index.ts:
const generator = orm.getSchemaGenerator();
await generator.updateSchema();
The main function in index.ts should now look like this:
const main = async () => {
const orm = await MikroORM.init(mikroConfig);
await orm.getMigrator().up;
const generator = orm.getSchemaGenerator();
await generator.updateSchema();
const post = orm.em.create(Post, { title: "my first post" });
await orm.em.persistAndFlush(post);
};
updateSchema creates a table or updates it based on .entities/Post.ts. This could cause issues when the Post file is updated, I haven't run in to any while following Ben's tutorial. Although, I'd still recommend creating ./create-schema.ts and running it when needed as shown in the official docs.
I have had the same issue. This is what I did:
I deleted the migrations folder as well as the dist folder
I ran npx mikro-orm migration:create --initial
After that, I restarted yarn watch and yarn dev and it worked for me.
Notice the --initial flag. I would recommend to check the official documentation. The migrations table is used to keep track of already executed migrations. When you only run npx mikro-orm migration:create, the table will not be created and therefore MikroORM is unable to check if the migration for the Post entity has already been performed (which includes creating the respective table on the database).
Ben does not use the --initial flag in his tutorial, he might have already ran it prior to the tutorial.
I had a similar problem myself (Also doing Ben Awad's tutorial).
I used Mikro-ORM's schema generator to initialize the table like in Fares47's Answer, but the problem still persisted.
It wasn't until I set my user to have Superuser permissions that it started working.
I am using postgresql for my data base which I downloaded using homebrew. If you have a similar set up here is what I did:
Start up psql in your terminal using psql postgres. If you want, you can view your users and check their permissions by typing \du in the shell. Then, to change the permissions for a user use the command ALTER ROLE <username> WITH SUPERUSER;. Make sure you include a semi-colon or else it will not run the command.
Check this article out for more info on psql commands.
I have the same problem i solved by install the ts-node on project
npm i -D ts-node
and set useTsNode on package.json as true.
The problem is the mikro-orm cli only add ts files paths in configPaths if the property useTsNode is true and ts-node is installed.
orther problem that i have is the regex in pattern property in mikro-orm.config.ts was wrong because a typo.
If any of the suggested steps didnt solve it for you, simply...
quit yarn watch and yarn dev
run this command from the command line
npx mikro-orm migration:up
now restart watch and dev and it you should be good.
from https://mikro-orm.io/docs/migrations/#migration-class
I also experienced this. And like Fares47 said it's possibly because I passed the username and password in ./mikro-orm.config.ts.
And my solution is simply execute the sql command that generated in ./src/migrations/Migration<NUMBERS>.ts file in postgresql terminal.
Here is the command that I execute in the database,
create table "post" ("id" serial primary key, "created_at" timestamptz(0) not null, "updated_at" timestamptz(0) not null, "title" text not null);
Just like what they suggested in the doc,
A safe approach would be generating the SQL on development server and
saving it into SQL Migration files that are executed manually on the
production server.
I'm trying to build a simple CRUD API with the MongoDB Rust driver but I'm failing to insert anything into the DB. I'm using Mlab to host my database.
The code that I'm running:
#[macro_use(bson, doc)]
extern crate bson;
extern crate mongodb;
use mongodb::db::ThreadedDatabase;
use mongodb::{Client, ThreadedClient};
fn main() {
let client = Client::with_uri(
"mongodb://<my_db_username>:<my_db_password>#ds235711.mlab.com:35711/rustcrud",
)
.expect("Failed to initialize client");
let coll = client.db("rustcrud").collection("test");
coll.insert_one(doc! { "title": "Back to the Future" }, None)
.unwrap();
}
And the error that I get:
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: OperationError("not authorized on rustcrud to execute command { insert: \"test\", $db: \"rustcrud\" }")', libcore/result.rs:1009:5
What am I doing wrong?
From the project's GitHub repository, issue 256: Add auth to base examples
user-password authentication occurs at the database-level. The user, password, and database are parsed from the URI, but I don't believe we have it set up to automatically authenticate when you create the database object
let client = Client::with_uri("mongodb://x:y#localhost:27017")?;
client.auth("x", "y");
I tried inserting a new XA-Datasource in Wildfly 8.1:
/opt/wildfly/bin/jboss-cli.sh --connect --controller=192.168.1.220:9990
[standalone#192.168.1.220:9990 /] xa-data-source add --name=myName --jndi-name=java:jboss/datasources/myDS --driver-name=postgresql --user-name=myUser --password=myPass --use-java-context=true --use-ccm=true --min-pool-size=10 --max-pool-size=100 --transaction-isolation=TRANSACTION_READ_COMMITTED --pool-prefill=true --allocation-retry=1 --prepared-statements-cache-size=32 --share-prepared-statements=true --xa-datasource-class=org.postgresql.xa.PGXADataSource --xa-datasource-properties=[{ServerName=192.168.1.220},{PortNumber=5432},{DatabaseName=postgres}] --valid-connection-checker-class-name=org.jboss.jca.adapters.jdbc.extensions.postgres.PostgreSQLValidConnectionChecker --exception-sorter-properties=org.jboss.jca.adapters.jdbc.extensions.postgres.PostgreSQLExceptionSorter
But I received this error:
{"JBAS014653: Composite operation failed and was rolled back. Steps that failed:" => {"Operation step-1" => "JBAS014688: Wrong type for exception-sorter-properties. Expected [OBJECT] but was LIST"}}
In the Web interface the value for Exception Sorter is a simple string.
I tried many value types.
Use --exception-sorter-class-name=org.jboss.jca.adapters.jdbc.extensions.postgres.PostgreSQLExceptionSorter instead of --exception-sorter-properties=org.jboss.jca.adapters.jdbc.extensions.postgres.PostgreSQLExceptionSorter.
I have just started using Elixir, so I figure I have some basic misunderstanding going on here. Here is the code...
defmodule Mdb do
def connect(collection, this_db \\ "db-test") do
{:ok, mongo} = Mongo.connect("db-test.some-mongo-server.com", 12345)
db = mongo |> Mongo.db(this_db)
db |> Mongo.auth("user", "secretpassword")
db
end
end
I start with iex -S mix
and when I try db = Mdb.connect("users") I get
** (UndefinedFunctionError) undefined function: Mongo.auth/3
Mongo.auth(%Mongo.Db{auth: nil, mongo: %Mongo.Server{host: 'db-test.some-mongo-server.com', id_prefix: 12641, mode: :passive, opts: %{}, port: 12345, socket: #Port<0.5732>, timeout: 6000}, name: "db-stage", opts: %{mode: :passive, timeout: 6000}}, "user", "secretpassword")
(mdb_play) lib/mdb.ex:7: Mdb.connect/2
I looks like Mongo.auth/3 is undefined, but that makes no sense to me. Can any one point me towards my error?
thanks for the help
I just played around it, and faced the same error. As in the error message, Mongo.auth seems not defined, and it might be Mongo.Db.auth instead. However, I faced another error (ArgumentError) on Mongo.Db.auth too. It may be certain issue in the library.
** (ArgumentError) argument error
:erlang.byte_size
...
(mongo) lib/mongo_request.ex:43: Mongo.Request.cmd/3
(mongo) lib/mongo_db.ex:44: Mongo.Db.auth/1
I'm not familiar with the library, but after small change in Mongo.Db.auth, normal call seems started working.
I tried with the following sequence.
mongo = Mongo.connect!(server, port)
db = mongo |> Mongo.db(db_name)
db |> Mongo.Db.auth(user_name, password)
collection = db |> Mongo.Db.collection(collection_name)
collection |> Mongo.Collection.count()
The change I tried is in the following fork-repo.
https://github.com/parroty/elixir-mongo