Doctrine\ODM\MongoDB\Mapping\ClassMetadataInfo::mapField PHP Method

    public function mapField(array $mapping)
    {
        if (!isset($mapping['fieldName']) && isset($mapping['name'])) {
            $mapping['fieldName'] = $mapping['name'];
        }
        if (!isset($mapping['fieldName'])) {
            throw MappingException::missingFieldName($this->name);
        }
        if (!isset($mapping['name'])) {
            $mapping['name'] = $mapping['fieldName'];
        }
        if ($this->identifier === $mapping['name'] && empty($mapping['id'])) {
            throw MappingException::mustNotChangeIdentifierFieldsType($this->name, $mapping['name']);
        }
        if (isset($this->fieldMappings[$mapping['fieldName']])) {
            //throw MappingException::duplicateFieldMapping($this->name, $mapping['fieldName']);
        }
        if ($this->discriminatorField !== null && $this->discriminatorField == $mapping['name']) {
            throw MappingException::discriminatorFieldConflict($this->name, $this->discriminatorField);
        }
        if (isset($mapping['targetDocument']) && strpos($mapping['targetDocument'], '\\') === false && strlen($this->namespace)) {
            $mapping['targetDocument'] = $this->namespace . '\\' . $mapping['targetDocument'];
        }
        if (isset($mapping['collectionClass'])) {
            if (strpos($mapping['collectionClass'], '\\') === false && strlen($this->namespace)) {
                $mapping['collectionClass'] = $this->namespace . '\\' . $mapping['collectionClass'];
            }
            $mapping['collectionClass'] = ltrim($mapping['collectionClass'], '\\');
        }
        if (!empty($mapping['collectionClass'])) {
            $rColl = new \ReflectionClass($mapping['collectionClass']);
            if (!$rColl->implementsInterface('Doctrine\\Common\\Collections\\Collection')) {
                throw MappingException::collectionClassDoesNotImplementCommonInterface($this->name, $mapping['fieldName'], $mapping['collectionClass']);
            }
        }
        if (isset($mapping['discriminatorMap'])) {
            foreach ($mapping['discriminatorMap'] as $key => $class) {
                if (strpos($class, '\\') === false && strlen($this->namespace)) {
                    $mapping['discriminatorMap'][$key] = $this->namespace . '\\' . $class;
                }
            }
        }
        if (isset($mapping['cascade']) && isset($mapping['embedded'])) {
            throw MappingException::cascadeOnEmbeddedNotAllowed($this->name, $mapping['fieldName']);
        }
        $cascades = isset($mapping['cascade']) ? array_map('strtolower', (array) $mapping['cascade']) : array();
        if (in_array('all', $cascades) || isset($mapping['embedded'])) {
            $cascades = array('remove', 'persist', 'refresh', 'merge', 'detach');
        }
        if (isset($mapping['embedded'])) {
            unset($mapping['cascade']);
        } elseif (isset($mapping['cascade'])) {
            $mapping['cascade'] = $cascades;
        }
        $mapping['isCascadeRemove'] = in_array('remove', $cascades);
        $mapping['isCascadePersist'] = in_array('persist', $cascades);
        $mapping['isCascadeRefresh'] = in_array('refresh', $cascades);
        $mapping['isCascadeMerge'] = in_array('merge', $cascades);
        $mapping['isCascadeDetach'] = in_array('detach', $cascades);
        if (isset($mapping['type']) && $mapping['type'] === 'file') {
            $mapping['file'] = true;
        }
        if (isset($mapping['type']) && $mapping['type'] === 'increment') {
            $mapping['strategy'] = self::STORAGE_STRATEGY_INCREMENT;
        }
        if (isset($mapping['file']) && $mapping['file'] === true) {
            $this->file = $mapping['fieldName'];
            $mapping['name'] = 'file';
        }
        if (isset($mapping['distance']) && $mapping['distance'] === true) {
            $this->distance = $mapping['fieldName'];
        }
        if (isset($mapping['id']) && $mapping['id'] === true) {
            $mapping['name'] = '_id';
            $this->identifier = $mapping['fieldName'];
            if (isset($mapping['strategy'])) {
                $this->generatorType = constant(ClassMetadata::class . '::GENERATOR_TYPE_' . strtoupper($mapping['strategy']));
            }
            $this->generatorOptions = isset($mapping['options']) ? $mapping['options'] : array();
            switch ($this->generatorType) {
                case self::GENERATOR_TYPE_AUTO:
                    $mapping['type'] = 'id';
                    break;
                default:
                    if (!empty($this->generatorOptions['type'])) {
                        $mapping['type'] = $this->generatorOptions['type'];
                    } elseif (empty($mapping['type'])) {
                        $mapping['type'] = $this->generatorType === self::GENERATOR_TYPE_INCREMENT ? 'int_id' : 'custom_id';
                    }
            }
            unset($this->generatorOptions['type']);
        }
        if (!isset($mapping['nullable'])) {
            $mapping['nullable'] = false;
        }
        // Synchronize the "simple" and "storeAs" mapping information for backwards compatibility
        if (isset($mapping['simple']) && ($mapping['simple'] === true || $mapping['simple'] === 'true')) {
            $mapping['storeAs'] = ClassMetadataInfo::REFERENCE_STORE_AS_ID;
        }
        // Provide the correct value for the "simple" field for backwards compatibility
        if (isset($mapping['storeAs'])) {
            $mapping['simple'] = $mapping['storeAs'] === ClassMetadataInfo::REFERENCE_STORE_AS_ID;
        }
        if (isset($mapping['reference']) && isset($mapping['storeAs']) && $mapping['storeAs'] === ClassMetadataInfo::REFERENCE_STORE_AS_ID && !isset($mapping['targetDocument'])) {
            throw MappingException::simpleReferenceRequiresTargetDocument($this->name, $mapping['fieldName']);
        }
        if (isset($mapping['reference']) && empty($mapping['targetDocument']) && empty($mapping['discriminatorMap']) && (isset($mapping['mappedBy']) || isset($mapping['inversedBy']))) {
            throw MappingException::owningAndInverseReferencesRequireTargetDocument($this->name, $mapping['fieldName']);
        }
        if ($this->isEmbeddedDocument && $mapping['type'] === 'many' && CollectionHelper::isAtomic($mapping['strategy'])) {
            throw MappingException::atomicCollectionStrategyNotAllowed($mapping['strategy'], $this->name, $mapping['fieldName']);
        }
        if (isset($mapping['reference']) && $mapping['type'] === 'one') {
            $mapping['association'] = self::REFERENCE_ONE;
        }
        if (isset($mapping['reference']) && $mapping['type'] === 'many') {
            $mapping['association'] = self::REFERENCE_MANY;
        }
        if (isset($mapping['embedded']) && $mapping['type'] === 'one') {
            $mapping['association'] = self::EMBED_ONE;
        }
        if (isset($mapping['embedded']) && $mapping['type'] === 'many') {
            $mapping['association'] = self::EMBED_MANY;
        }
        if (isset($mapping['association']) && !isset($mapping['targetDocument']) && !isset($mapping['discriminatorField'])) {
            $mapping['discriminatorField'] = self::DEFAULT_DISCRIMINATOR_FIELD;
        }
        /*
        if (isset($mapping['type']) && ($mapping['type'] === 'one' || $mapping['type'] === 'many')) {
            $mapping['type'] = $mapping['type'] === 'one' ? self::ONE : self::MANY;
        }
        */
        if (isset($mapping['version'])) {
            $mapping['notSaved'] = true;
            $this->setVersionMapping($mapping);
        }
        if (isset($mapping['lock'])) {
            $mapping['notSaved'] = true;
            $this->setLockMapping($mapping);
        }
        $mapping['isOwningSide'] = true;
        $mapping['isInverseSide'] = false;
        if (isset($mapping['reference'])) {
            if (isset($mapping['inversedBy']) && $mapping['inversedBy']) {
                $mapping['isOwningSide'] = true;
                $mapping['isInverseSide'] = false;
            }
            if (isset($mapping['mappedBy']) && $mapping['mappedBy']) {
                $mapping['isInverseSide'] = true;
                $mapping['isOwningSide'] = false;
            }
            if (isset($mapping['repositoryMethod'])) {
                $mapping['isInverseSide'] = true;
                $mapping['isOwningSide'] = false;
            }
            if (!isset($mapping['orphanRemoval'])) {
                $mapping['orphanRemoval'] = false;
            }
        }
        $this->applyStorageStrategy($mapping);
        $this->fieldMappings[$mapping['fieldName']] = $mapping;
        if (isset($mapping['association'])) {
            $this->associationMappings[$mapping['fieldName']] = $mapping;
        }
        return $mapping;
    }

 /**
  * @param  \Symfony\Component\HttpKernel\Bundle\BundleInterface $bundle
  * @param  string                                               $document
  * @param  array                                                $fields
  * @param  Boolean                                              $withRepository
  * @throws \RuntimeException
  */
 public function generate(BundleInterface $bundle, $document, array $fields, $withRepository)
 {
     $config = $this->documentManager->getConfiguration();
     $config->addDocumentNamespace($bundle->getName(), $bundle->getNamespace() . '\\Document');
     $documentClass = $config->getDocumentNamespace($bundle->getName()) . '\\' . $document;
     $documentPath = $bundle->getPath() . '/Document/' . str_replace('\\', '/', $document) . '.php';
     if (file_exists($documentPath)) {
         throw new \RuntimeException(sprintf('Document "%s" already exists.', $documentClass));
     }
     $class = new ClassMetadataInfo($documentClass);
     if ($withRepository) {
         $class->setCustomRepositoryClass($documentClass . 'Repository');
     }
     $class->mapField(array('fieldName' => 'id', 'type' => 'integer', 'id' => true));
     $class->setIdGeneratorType(ClassMetadataInfo::GENERATOR_TYPE_AUTO);
     foreach ($fields as $field) {
         $class->mapField($field);
     }
     $documentGenerator = $this->getDocumentGenerator();
     $documentCode = $documentGenerator->generateDocumentClass($class);
     $this->filesystem->mkdir(dirname($documentPath));
     file_put_contents($documentPath, rtrim($documentCode) . PHP_EOL, LOCK_EX);
     if ($withRepository) {
         $path = $bundle->getPath() . str_repeat('/..', substr_count(get_class($bundle), '\\'));
         $this->getRepositoryGenerator()->writeDocumentRepositoryClass($class->customRepositoryClassName, $path);
     }
 }