I started the Mercure hub with this command on Windows10 :

mercure --jwt-key="eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJtZXJjdXJlIjp7InB1Ymxpc2giOltdfX0.Oo0yg7y4yMa1vr_bziltxuTCqb8JVHKxp-f_FwwOim0" --addr="localhost:3000" --allow-anonymous --cors-allowed-origins="*"

The hub run successfully

I want to publish updates from Symfony :

In the .env file there is :

###> symfony/mercure-bundle ###
# See https://symfony.com/doc/current/mercure.html#configuration
MERCURE_PUBLISH_URL=http://mercure/.well-known/mercure
# The default token is signed with the secret key: !ChangeMe!
MERCURE_JWT_TOKEN=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJtZXJjdXJlIjp7InB1Ymxpc2giOltdfX0.Oo0yg7y4yMa1vr_bziltxuTCqb8JVHKxp-f_FwwOim0
###< symfony/mercure-bundle ###

In the lexik_jwt_authentication.yaml :

lexik_jwt_authentication:
    secret_key: '%env(resolve:JWT_SECRET_KEY)%'
    public_key: '%env(resolve:JWT_PUBLIC_KEY)%'
    pass_phrase: '%env(JWT_PASSPHRASE)%'
    token_ttl: '%env(JWT_TOKEN_TTL)%'
    user_identity_field: username

Then in the Symfony :

/**
     * @RestPost("/api/insertUpdateSynonyms", name ="api_insert_update_synonyms")
     * @RestRequestParam(name="old_cle", nullable=true)
     * @RestRequestParam(name="add_synonymes", nullable=true)
     * @RestRequestParam(name="new_cle", nullable=true)
     * @RestRequestParam(name="new_synonymes", nullable=true)
     *
     * @return JsonResponse
     */
    public function insertUpdateSynonyms(ParamFetcher $paramFetcher, SearchService $searchService, PublisherInterface $publisher)
    {
        try {
            $retour = $searchService->insertUpdateSynonyms($paramFetcher);
            $update = new Update(
                'http://bdc.pulse.mg/notif/suggestioncontenu',
                json_encode(['msg' => '============================= new content updated ! ................................'])
            );
            $publisher($update);
        } catch (Exception $e) {
            $retour = array('error' => array('error_code' => $e->getCode(), 'message' => $e->getMessage()));
        }
        $response = new JsonResponse();
        $response->setData($retour);
        return $response;
    }

In the Angular side :

insertSynonyme(){
    const data = {
      old_cle: this.synoForm.value.cle_syno,
      add_synonymes: this.dataSynonyme.oldSynonyme
    };
    this.generalServ.insertSynonyme(data).subscribe( 
      res => {
        console.log(res);
        if(res.code === 200){
          this.toastr.success('Sent');
          this.submitted = true;
          // this._document.defaultView.location.reload();
        }
      });
  }

At runtime the console shows error_code 401 : HTTP/1.1 401 Unauthorized returned for "http://localhost:3000/.well-known/mercure

So what is wrong ?

Source: Symfony4 Questions