Azure Cosmos + Gremlin NodeJS, how to submit fluent query as script (not bytecode -- i know its not supported yet)

Question

I'm trying to write fluent gremlin queries in nodejs for cosmos db, even though they get submitted as string. I've been through the documentation and I've seen it mentioned in a few github threads that although bytecode isn't yet supported, it is possible to submit it as scrip.

The code I have so far:

Configuring the client function:


export const CosmosConn = async (): Promise<driver.Client> => {
    try {
        const cosmosKey: string = await GetSecret('cosmos-key');
        const cosmosEndpoint: string = await GetSecret('cosmos-endpoint');

        const authenticator: driver.auth.PlainTextSaslAuthenticator = new gremlin.driver.auth.PlainTextSaslAuthenticator(
            '/dbs/main/colls/main',
            cosmosKey
        );
        const client: driver.Client = new gremlin.driver.Client(cosmosEndpoint, {
            authenticator,
            traversalsource: 'g',
            rejectUnauthorized: true,
            mimeType: 'application/vnd.gremlin-v2.0+json'
        });

        return client;
    } catch (err) {
        console.error(err);
    }
};

Now these two below are temporary as i'll await that CosmosConn several times for every query, but this is for an Azure Function so i'm not optimizing yet:

export const Graph = async (query: gremlin.process.Bytecode): Promise<any> => {
    const db = await CosmosConn();
    const translator = new gremlin.process.Translator(
        new gremlin.process.AnonymousTraversalSource()
    );
    return db.submit(translator.translate(query));
};

export const getGremlin = async () => {
    const db = await CosmosConn();
    return gremlin.process.traversal().withRemote(db);
};

Now when I try to use it:

    const g = await getGremlin();
        const query = g
            .V()
            .hasLabel('client')
            .getBytecode();

        const test = await Graph(query);

This of course throws out an error:

Gremlin Query Syntax Error: Script compile error: Unexpected token: 'Object'; in input: '[objectObject'. @ line 1, column 9.

score 1 · Answer 1 · answered Nov 12 '19 at 14:21

1

Have you tried to print the translator.translate(query) prior submitting?

From my experience, the translator is very limited in its support for non-trivial queries.

According to Microsoft, they plan to support fluent API on Dec 19', so probably better to wait for official support.

answered Nov 12 '19 at 14:21

Kfir Dadosh

1,411
9
9

I'm happy to wait a few more weeks, it's just that the fluent API was promised in first half of 2018, so not sure how much to trust that deadline. – SebastianG Nov 12 '19 at 14:51
2

literally the next day after you posted this, they have updated the timeline for this to first half of 2020, so, maybe July 2020 if we're lucky? – SebastianG Nov 21 '19 at 12:48
This is a shame. Good thing they have competition (Amazon Neptune?) – Kfir Dadosh Nov 21 '19 at 15:04
Ah, I don't want to move all of our infrastructure out of Azure for this :( it is however getting more and more frustrating with some things... – SebastianG Nov 21 '19 at 15:09
2

hello from September 2020 :-/ – gbanks Sep 07 '20 at 21:03
hello from 2021 and I've not used Azure since 3 jobs ago :) – SebastianG May 22 '21 at 15:12
Hello from February 2023 – EddieDean Feb 03 '23 at 22:33

score 0 · Accepted Answer · answered Nov 26 '19 at 17:22

0

It was the types preventing me from initialising my translator in a way that works with CosmosDB.

    const translator = new gremlin.process.Translator('g' as any);

works.

answered Nov 26 '19 at 17:22

SebastianG

8,563
8
47
111

score 0 · Answer 3 · answered Dec 25 '19 at 22:00

Dawn below is an example of using Translator in TypeScript to convert bytecode query to string query for CosmosDB. I don't recommend this solution, like the other response pointed out: it's limited. Use AWS Neptune instead or wait until MS implements bytecode queries in CosmosDB.

async function test(): Promise<void> {
   // Connection:
   const traversal = Gremlin.process.AnonymousTraversalSource.traversal;
   const DriverRemoteConnection = Gremlin.driver.DriverRemoteConnection;
   const g = traversal().withRemote(new DriverRemoteConnection("ws://localhost:8182/gremlin"));

   // Create translator
   const translator = new Gremlin.process.Translator(g);

   // Convert bytecode query to string query for CosmosDB:
   console.log(translator.translate(g.V().hasLabel('person').values('name').getBytecode()))
}

test();

iAviator · Answer 4 · 2021-05-22T11:56:29.570

-1

Here is the link to tests cases to get getbytecode translation working.

https://github.com/apache/tinkerpop/blob/master/gremlin-javascript/src/main/javascript/gremlin-javascript/test/unit/translator-test.js#L31

Edit:-

Here is sample test case from above link

it('should produce valid script representation from bytecode glv steps', function () {
      const g = new graph.Graph().traversal();
      const script = new Translator('g').translate(g.V().out('created').getBytecode());
      assert.ok(script);
      assert.strictEqual(script, 'g.V().out(\'created\')');
});

edited May 22 '21 at 11:56

answered May 22 '21 at 10:55

iAviator

1,310
13
31

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - [From Review](/review/low-quality-posts/29031266) – David Maze May 22 '21 at 11:32
Edited the answer with sample test case – iAviator May 22 '21 at 11:57

Azure Cosmos + Gremlin NodeJS, how to submit fluent query as script (not bytecode -- i know its not supported yet)

4 Answers4