Could not perform discovery errors

[tgod009]

Code that's throwing error:

clients.map(async (client) => {
      let tenant = client.tenant;
      let clientId = client.client_id;
      let clientName = client.name;

      const query = new QuerySpecification()
        .withStatement(
          "MERGE(c:Client {client_id: '$clientId', app_name: '$clientName'})-[r:CLIENT_OF]->(t:Tenant {name: '$tenant'})'RETURN c, r, t'",
        )
        .bind([clientId, clientName, tenant]);
      await this.persistenceManager.execute(query);

  Full error
  
  Error: Cannot run query in this transaction, because it has already been committed.
at Function.withRootCause (/home/taylor/modsquad/cubeless-backend/app/node_modules/@liberation-data/src/DrivineError.ts:8:16)
at Transaction.query (/home/taylor/modsquad/cubeless-backend/app/node_modules/@liberation-data/src/transaction/Transaction.ts:51:32)
at TransactionalPersistenceManager.execute (/home/taylor/modsquad/cubeless-backend/app/node_modules/@liberation-data/src/manager/TransactionalPersistenceManager.ts:28:9)
at /home/taylor/modsquad/cubeless-backend/app/src/clients/clients.service.ts:54:7

[jasperblues]

@tgod009 I have seen this error on recent Neo4j JS driver. Can you please try using the Neo4j driver directly? Does it work?

[tgod009]

@jasperblues finally got around to trying with the neo4j driver directly and it worked. Any ideas why that is?

[jasperblues]

@tgod009 are you able to share a sample where it works directly but not with drivine? That would be much appreciated and should certainly lead to a solution.

[tgod009]

I just initalized the driver in my service file and called the session like so

const session = this.driver.session();
    session
      .run('Merge (a:Application {name: $appName})', {
        appName: createUserApplications.app_name,
      })
      .then((result) => {
        return result.records.map((record) => {
          return record.get('a');
        });
      })
      .catch((error) => {
        console.log(error);
      })
      .then(() => {
        session.close();
      });

[jasperblues]

And the same thing does not work for you drivine @tgod009 ?

[tgod009]

Running Drivine like this throws the routing table error

const query = new QuerySpecification()
      .withStatement('Merge(a:Application {name: $appName})')
      .bind(createUserApplications);
    return this.persistenceManager.execute(query);

 ERROR [ExceptionsHandler] Could not perform discovery. No routing servers available. Known routing table: RoutingTable[database=default database, expirationTime=0, currentTime=1679379048963, routers=[], readers=[], writers=[]]

[jasperblues]

Here's what I did to make it work:

• Clone the drivine repository (this one).
• Copy .env.sampe to .env and change the neo4j password to appropriate pass.
• Modify the file RouteRepository. Add this code:

    @Transactional()
    async createApp(name: string): Promise<void> {
        const query = new QuerySpecification()
            .withStatement('Merge(a:Application {name: $appName})')
            .bind({appName: name});
        return this.persistenceManager.execute(query);
    }

^-- Note that the params are slightly different. Since we bind name parameters we supply the name.

Final Step

Modify the RouteRepository.spec.ts. Add this test:

    it('should create an app', async () => {
        await repo.createApp("foobar")
    });

The test passes. If you want to see the result in the DB, at the top of that file change the following:

RunWithDrivine({rollback: false}); <-- change rollback to false

If you follow the approach above, does it work for you? The may be an issue but the above works for me.

[tgod009]

That's with the sample application?

[jasperblues]

No, I just added it to Drivine directly. You can clone that repo, create an env file, then run the tests.

Run this gist for most tests to pass: https://gist.github.com/jasperblues/7a6e774090c9ef0f18c44920b48b6b23

There are two tests that need additional setup steps. Don't worry about those, just add the code above and let me know what happens with your Neo4j server. If it works - it was a setup issue. If it does, its something environment related.

I was going to add to the sample app, but I think I need to freshen dependencies. (Will do shortly).

[tgod009]

I gave it try and I got the same error using my db info

Error: Could not perform discovery. No routing servers available. Known routing table: RoutingTable[database=default database, expirationTime=0, currentTime=1679435963014, routers=[], readers=[], writers=[]]

[tgod009]

Side note not sure if this effects it but I'm using Aura not a local DB with the encrypted url

[jasperblues]

@tgod009 I will see if I can reproduce with Aura.

[tgod009]

Not sure if this was causing it but I did just notice that I was using the non encrypted protocol

[jasperblues]

If you can try with both and compare results that would be great. This is puzzling!