Examples with SemanticDomain org.talend.dataprep.api.dataset.statistics.SemanticDomain used on opensource projects

Example 11 with SemanticDomain

use of org.talend.dataprep.api.dataset.statistics.SemanticDomain in project data-prep by Talend.

the class TransformationService method getPreparationColumnSemanticCategories.

/**
 * Return the semantic types for a given preparation / column.
 *
 * @param preparationId the preparation id.
 * @param columnId the column id.
 * @param stepId the step id (optional, if not specified, it's 'head')
 * @return the semantic types for a given preparation / column.
 */
@RequestMapping(value = "/preparations/{preparationId}/columns/{columnId}/types", method = GET)
@ApiOperation(value = "list the types of the wanted column", notes = "This list can be used by user to change the column type.")
@Timed
@PublicAPI
public List<SemanticDomain> getPreparationColumnSemanticCategories(@ApiParam(value = "The preparation id") @PathVariable String preparationId, @ApiParam(value = "The column id") @PathVariable String columnId, @ApiParam(value = "The preparation version") @RequestParam(defaultValue = "head") String stepId) {
    LOG.debug("listing preparation semantic categories for preparation #{} column #{}@{}", preparationId, columnId, stepId);
    // get the preparation
    final Preparation preparation = getPreparation(preparationId);
    // get the step (in case of 'head', the real step id must be found)
    final String version = // 
    StringUtils.equals("head", stepId) ? preparation.getSteps().get(preparation.getSteps().size() - 1).getId() : stepId;
    /*
         * OK, this one is a bit tricky so pay attention.
         *
         * To be able to get the semantic types, the analyzer service needs to run on the result of the preparation.
         *
         * The result must be found in the cache, so if the preparation is not cached, the preparation is run so that
         * it gets cached.
         *
         * Then, the analyzer service just gets the data from the cache. That's it.
         */
    // generate the cache keys for both metadata & content
    final ContentCacheKey metadataKey = cacheKeyGenerator.metadataBuilder().preparationId(preparationId).stepId(version).sourceType(HEAD).build();
    final ContentCacheKey contentKey = cacheKeyGenerator.contentBuilder().datasetId(preparation.getDataSetId()).preparationId(preparationId).stepId(// 
    version).format(JSON).sourceType(// 
    HEAD).build();
    // if the preparation is not cached, let's compute it to have some cache
    if (!contentCache.has(metadataKey) || !contentCache.has(contentKey)) {
        addPreparationInCache(preparation, stepId);
    }
    // run the analyzer service on the cached content
    try (final InputStream metadataCache = contentCache.get(metadataKey);
        final InputStream contentCache = this.contentCache.get(contentKey)) {
        final DataSetMetadata metadata = mapper.readerFor(DataSetMetadata.class).readValue(metadataCache);
        final List<SemanticDomain> semanticDomains = getSemanticDomains(metadata, columnId, contentCache);
        LOG.debug("found {} for preparation #{}, column #{}", semanticDomains, preparationId, columnId);
        return semanticDomains;
    } catch (IOException e) {
        throw new TDPException(UNEXPECTED_EXCEPTION, e);
    }
}