getEntityResourcePostUrl example

  public function testPostDxWithoutCriticalBaseFields() {
    $this->initAuthentication();
    $this->provisionEntityResource();
    $this->setUpAuthorization('POST');

    $url = $this->getEntityResourcePostUrl()->setOption('query', ['_format' => static::$format]);
    $request_options = [];
    $request_options[RequestOptions::HEADERS]['Accept'] = static::$mimeType;
    $request_options[RequestOptions::HEADERS]['Content-Type'] = static::$mimeType;
    $request_options = array_merge_recursive($request_options, $this->getAuthenticationRequestOptions('POST'));

    // DX: 422 when missing 'entity_type' field.     $request_options[RequestOptions::BODY] = $this->serializer->encode(array_diff_key($this->getNormalizedPostEntity(), ['entity_type' => TRUE]), static::$format);
    $response = $this->request('POST', $url, $request_options);
    $this->assertResourceErrorResponse(422, "Unprocessable Entity: validation failed.\nentity_type: This value should not be null.\n", $response);

    // DX: 422 when missing 'entity_id' field.

    $unparseable_request_body = '!{>}<';
    $parseable_valid_request_body = $this->serializer->encode($this->getNormalizedPostEntity(), static::$format);
    $parseable_invalid_request_body = $this->serializer->encode($this->makeNormalizationInvalid($this->getNormalizedPostEntity(), 'label'), static::$format);
    $parseable_invalid_request_body_2 = $this->serializer->encode($this->getNormalizedPostEntity() + ['uuid' => [$this->randomMachineName(129)]], static::$format);
    $parseable_invalid_request_body_3 = $this->serializer->encode($this->getNormalizedPostEntity() + ['field_rest_test' => [['value' => $this->randomString()]]], static::$format);

    // The URL and Guzzle request options that will be used in this test. The     // request options will be modified/expanded throughout this test:     // - to first test all mistakes a developer might make, and assert that the     // error responses provide a good DX     // - to eventually result in a well-formed request that succeeds.     $url = $this->getEntityResourcePostUrl();
    $request_options = [];

    // DX: 404 when resource not provisioned. HTML response because missing     // ?_format query string.     $response = $this->request('POST', $url, $request_options);
    $this->assertSame(404, $response->getStatusCode());
    $this->assertSame(['text/html; charset=UTF-8'], $response->getHeader('Content-Type'));

    $url->setOption('query', ['_format' => static::$format]);

    // DX: 404 when resource not provisioned.