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Perturbs a JSON string with random variations.

fuzzJSON({ named_collection [, option=value [,..]] | json_str[, random_seed] })


  • named_collection- A NAMED COLLECTION.
  • option=value - Named collection optional parameters and their values.
  • json_str (String) - The source string representing structured data in JSON format.
  • random_seed (UInt64) - Manual random seed for producing stable results.
  • reuse_output (boolean) - Reuse the output from a fuzzing process as input for the next fuzzer.
  • malform_output (boolean) - Generate a string that cannot be parsed as a JSON object.
  • max_output_length (UInt64) - Maximum allowable length of the generated or perturbed JSON string.
  • probability (Float64) - The probability to fuzz a JSON field (a key-value pair). Must be within [0, 1] range.
  • max_nesting_level (UInt64) - The maximum allowed depth of nested structures within the JSON data.
  • max_array_size (UInt64) - The maximum allowed size of a JSON array.
  • max_object_size (UInt64) - The maximum allowed number of fields on a single level of a JSON object.
  • max_string_value_length (UInt64) - The maximum length of a String value.
  • min_key_length (UInt64) - The minimum key length. Should be at least 1.
  • max_key_length (UInt64) - The maximum key length. Should be greater or equal than the min_key_length, if specified.

Returned Value

A table object with a a single column containing perturbed JSON strings.

Usage Example

CREATE NAMED COLLECTION json_fuzzer AS json_str='{}';
SELECT * FROM fuzzJSON(json_fuzzer) LIMIT 3;
SELECT * FROM fuzzJSON(json_fuzzer, json_str='{"name" : "value"}', random_seed=1234) LIMIT 3;
{"key":"value", "mxPG0h1R5":"L-YQLv@9hcZbOIGrAn10%GA"}
{"key":"value", "SWzJdEJZ04nrpSfy":[{"3Q23y":[]}]}
SELECT * FROM fuzzJSON(json_fuzzer, json_str='{"students" : ["Alice", "Bob"]}', reuse_output=true) LIMIT 3;
{"students":["Alice", "Bob"], "nwALnRMc4pyKD9Krv":[]}
{"students":["1rNY5ZNs0wU&82t_P", "Bob"], "wLNRGzwDiMKdw":[{}]}
{"xeEk":["1rNY5ZNs0wU&82t_P", "Bob"], "wLNRGzwDiMKdw":[{}, {}]}
SELECT * FROM fuzzJSON(json_fuzzer, json_str='{"students" : ["Alice", "Bob"]}', max_output_length=512) LIMIT 3;
{"students":["Alice", "Bob"], "BREhhXj5":true}
{"NyEsSWzJdeJZ04s":["Alice", 5737924650575683711, 5346334167565345826], "BjVO2X9L":true}
{"NyEsSWzJdeJZ04s":["Alice", 5737924650575683711, 5346334167565345826], "BjVO2X9L":true, "k1SXzbSIz":[{}]}
SELECT * FROM fuzzJSON('{"id":1}', 1234) LIMIT 3;
{"id":1, "mxPG0h1R5":"L-YQLv@9hcZbOIGrAn10%GA"}
SELECT * FROM fuzzJSON(json_nc, json_str='{"name" : "FuzzJSON"}', random_seed=1337, malform_output=true) LIMIT 3;
{"name"keFuzzJSON, "g6vVO7TCIk":jTt^