NealSun96 commented on a change in pull request #761: Add REST read endpoints to helix-rest for metadata store directory URL: https://github.com/apache/helix/pull/761#discussion_r381456004
########## File path: helix-rest/src/main/java/org/apache/helix/rest/server/resources/metadatastore/MetadataStoreDirectoryAccessor.java ########## @@ -111,41 +132,56 @@ public Response deleteMetadataStoreRealm(@PathParam("realm") String realm) { } /** - * Gets sharding keys mapped at path "HTTP GET /sharding-keys" which returns all sharding keys in - * a namespace, or path "HTTP GET /sharding-keys?realm={realmName}" which returns sharding keys in - * a realm. + * Gets all sharding keys mapped at paths: + * - "HTTP GET /sharding-keys" which returns all sharding keys in a namespace. + * - "HTTP GET /sharding-keys?realm={realm}" which returns sharding keys in the realm. + * - "HTTP GET /sharding-keys?prefix={prefix}" which returns sharding keys that have the prefix. + * -- JSON response example for this path: + * { + * "prefix": "/sharding/key", + * "shardingKeys": [{ + * "realm": "testRealm2", + * "shardingKey": "/sharding/key/1/f" + * }, { + * "realm": "testRealm2", + * "shardingKey": "/sharding/key/1/e" + * }, { + * "realm": "testRealm1", + * "shardingKey": "/sharding/key/1/b" + * }, { + * "realm": "testRealm1", + * "shardingKey": "/sharding/key/1/a" + * }] + * } + * + * - "HTTP GET /sharding-keys?realm={realm}&prefix={prefix}" which returns sharding keys in the + * realm and that have the prefix. * - * @param realm Query param in endpoint path - * @return Json representation of a map: shardingKeys -> collection of sharding keys. + * @param realm Query param in endpoint path: metadata store realm. + * @param prefix Query param in endpoint path: prefix substring of sharding key. + * @return Json representation for the sharding keys. */ @GET @Path("/sharding-keys") - public Response getShardingKeys(@QueryParam("realm") String realm) { - Map<String, Object> responseMap; - Collection<String> shardingKeys; + public Response getShardingKeys(@QueryParam("realm") String realm, + @QueryParam("prefix") String prefix) { try { - // If realm is not set in query param, the endpoint is: "/sharding-keys" - // to get all sharding keys in a namespace. - if (realm == null) { - shardingKeys = _metadataStoreDirectory.getAllShardingKeys(_namespace); - // To avoid allocating unnecessary resource, limit the map's capacity only for - // SHARDING_KEYS. - responseMap = new HashMap<>(1); + if (realm == null && prefix == null) { + // For endpoint: "/sharding-keys" to get all sharding keys in a namespace. + return getAllShardingKeys(); + } else if (prefix == null) { + // For endpoint: "/sharding-keys?realm={realm}" + return getAllShardingKeysInRealm(realm); + } else if (realm == null) { + // For endpoint: "/sharding-keys?prefix={prefix}" + return getAllShardingKeysUnderPath(prefix); } else { - // For endpoint: "/sharding-keys?realm={realmName}" - shardingKeys = _metadataStoreDirectory.getAllShardingKeysInRealm(_namespace, realm); - // To avoid allocating unnecessary resource, limit the map's capacity only for - // SHARDING_KEYS and SINGLE_METADATA_STORE_REALM. - responseMap = new HashMap<>(2); - responseMap.put(MetadataStoreRoutingConstants.SINGLE_METADATA_STORE_REALM, realm); + // For endpoint: "/sharding-keys?realm={realm}&prefix={prefix}" + return getRealmShardingKeysUnderPath(realm, prefix); Review comment: When the prefix parameter is not provided, it's treated as the caller doesn't care about the prefix - this method is doing "return all keys regardless of any prefix". This behavior is functionally the same as if the caller provides "/" as the prefix. I think it's reasonable to use "/" as a default value. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@helix.apache.org For additional commands, e-mail: reviews-h...@helix.apache.org