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PHP unserialize in Postgresql to json
/**
Decode a php serialized value to json. This function only supports basic
data types:
- arrays (will always become a json object)
- booleans
- integers
- floats
- strings
- NULL
The php_unserialize(text) function is a helper function which extracts the first value
found in the string and returns a ROW( vartype, varval, serializedlength)
The php_unserialize_to_json(text) function returns the json value extracted from
the serialized string.
Examples:
SELECT php_unserialize_to_json('a:5:{i:0;d:1;s:1:"k";a:3:{i:0;s:1:"a";i:1;s:1:"b";s:3:"sub";a:3:{i:0;s:1:"a";i:1;s:1:"b";i:2;s:1:"c";}}i:1;N;i:2;b:1;i:3;b:0;}')#>>'{k,sub,2}';
SELECT php_unserialize_to_json('s:8:"a string";');
SELECT php_unserialize_to_json('s:0:"";');
SELECT php_unserialize_to_json('i:1337;');
SELECT php_unserialize_to_json('d:1.234;');
SELECT php_unserialize_to_json('b:1;')::TEXT;
SELECT php_unserialize_to_json('b:0;')::TEXT;
SELECT php_unserialize_to_json('N;')::TEXT;
SELECT php_unserialize_to_json('a:0:{}')::TEXT;
SELECT php_unserialize_to_json('a:1:{i:0;s:5:"array";}')::TEXT;
SELECT php_unserialize_to_json('a:1:{i:0;i:1;}')::TEXT;
SELECT php_unserialize_to_json('a:2:{i:0;i:1;i:1;s:1:"b";}')::TEXT;
SELECT php_unserialize_to_json('a:2:{i:0;d:1;s:1:"k";s:1:"b";}')::TEXT;
SELECT php_unserialize_to_json('a:2:{i:0;d:1;s:1:"k";a:2:{i:0;s:1:"a";i:1;s:1:"b";}}')::TEXT;
*/
---
--- This function is the helper function
---
CREATE OR REPLACE FUNCTION php_unserialize(str text)
RETURNS json AS
$BODY$
DECLARE
vartype CHAR;
varlength INT;
jsonstr TEXT;
varcount INT;
jsonval JSONB;
arrkey JSON;
arrval JSON;
-- String length of the serialized data
serialized_string_length INT;
BEGIN
CASE substring(str, 1, 1)
WHEN 'a' THEN -- array
-- init object
jsonval := '{}'::jsonb;
-- remove the "a" and ":" characters
str := substring(str, 3);
-- Detect number of values in array
varlength := substring(str, 1, position(':' IN str) - 1)::INT;
-- Base size of array is 5 (a:[size]:{})
serialized_string_length := 5 + char_length(varlength::TEXT);
-- If no values, return empty object, as this always returns objects
IF varlength = 0 THEN
return json_build_array('array', jsonval, serialized_var_size)::JSON;
END IF;
-- remove the array size and ":{"
str := substring(str, char_length(varlength::TEXT) + 3);
-- Find the number of variables specified
FOR varcount IN 1 .. varlength LOOP
-- Find the value of the key and remove it from base string
arrkey := php_unserialize(str);
str := substring(str, (arrkey->>2)::INT + 1);
-- Find the value of the value and remove it from base string
arrval := php_unserialize(str);
str := substring(str, (arrval->>2)::INT + 1);
serialized_string_length := serialized_string_length + (arrkey->>2)::INT + (arrval->>2)::INT;
-- Append value
jsonval := jsonval || jsonb_build_object(arrkey->>1, arrval->1);
END LOOP;
return json_build_array('array', jsonval, serialized_string_length);
WHEN 'b' THEN -- boolean
return json_build_array('bool',(CASE substring(str, 3, 1) WHEN '1' THEN TRUE ELSE FALSE END)::TEXT, 4);
WHEN 'd' THEN -- float
return json_build_array('float', substring(str, 3, position(';' IN str) - 3)::TEXT, position(';' IN str));
WHEN 'i' THEN -- int
return json_build_array('int', substring(str, 3, position(';' IN str) - 3)::TEXT, position(';' IN str));
WHEN 'N' THEN -- null
return json_build_array('null', 'null'::TEXT, 2);
WHEN 's' THEN -- string
varlength := substring(str, 3, position(':' IN str) - 1)::INT;
return json_build_array('string', substring(str, char_length(varlength::TEXT) + 5, varlength)::TEXT, position(';' IN str));
ELSE
RAISE EXCEPTION 'Unable to decode serialized value, unsupported type: %', substr(str, 1, 1);
END CASE;
END;
$BODY$
LANGUAGE plpgsql IMMUTABLE
COST 10;
---
--- The main function
---
CREATE OR REPLACE FUNCTION php_unserialize_to_json(str text)
RETURNS json AS
$BODY$
DECLARE
varlength INT;
BEGIN
CASE substring(str, 1, 1)
WHEN 'a' THEN
return php_unserialize(str)->1;
WHEN 'b' THEN
return php_unserialize(str)->1;
WHEN 'd' THEN
return php_unserialize(str)->1;
WHEN 'i' THEN
return php_unserialize(str)->1;
WHEN 'N' THEN
return php_unserialize(str)->1;
WHEN 's' THEN
return php_unserialize(str)->1;
ELSE
RETURN NULL;
END CASE;
END;
$BODY$
LANGUAGE plpgsql IMMUTABLE
COST 10;
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