def redis_test():
rj = Client(host='localhost', port=6379)
# Set the key `obj` to some object
obj = {
'answer': 42,
'arr': [None, True, 3.14],
'truth': {
'coord': 'out there'
}
}
rj.jsonset('obj', Path.rootPath(), obj)
# Get something
print ('Is there anybody... {}?'.format(
rj.jsonget('obj', Path('.truth.coord'))
))
# Delete something (or perhaps nothing), append something and pop it
rj.jsondel('obj', Path('.arr[0]'))
rj.jsonarrappend('obj', Path('.arr'), 'something')
print ('{} popped!'.format(rj.jsonarrpop('obj', Path('.arr'))))
# Update something else
rj.jsonset('obj', Path('.answer'), 2.17)
# And use just like the regular redis-py client
jp = rj.pipeline()
jp.set('foo', 'bar')
jp.jsonset('baz', Path.rootPath(), 'qaz')
jp.execute()
def testUsageExampleShouldSucceed(self):
"Test the usage example"
# Create a new rejson-py client
rj = Client(host='localhost', port=port, decode_responses=True)
# Set the key `obj` to some object
obj = {
'answer': 42,
'arr': [None, True, 3.14],
'truth': {
'coord': 'out there'
}
}
rj.jsonset('obj', Path.rootPath(), obj)
# Get something
rv = rj.jsonget('obj', Path('.truth.coord'))
self.assertEqual(obj['truth']['coord'], rv)
# Delete something (or perhaps nothing), append something and pop it
value = "something"
rj.jsondel('obj', Path('.arr[0]'))
rj.jsonarrappend('obj', Path('.arr'), value)
rv = rj.jsonarrpop('obj', Path('.arr'))
self.assertEqual(value, rv)
# Update something else
value = 2.17
rj.jsonset('obj', Path('.answer'), value)
rv = rj.jsonget('obj', Path('.answer'))
self.assertEqual(value, rv)
# And use just like the regular redis-py client
jp = rj.pipeline()
jp.set('foo', 'bar')
jp.jsonset('baz', Path.rootPath(), 'qaz')
jp.execute()
rv1 = rj.get('foo')
self.assertEqual('bar', rv1)
rv2 = rj.jsonget('baz')
self.assertEqual('qaz', rv2)
class ReJson:
"""Facade for ReJson"""
def __init__(self, host: str, port: Union[str, int]) -> None:
"""Instantiate a connection to ReJson.
:param host: The hostname/ip of the Redis instance.
:type host: str
:param port: The port of the Redis instance.
:type port: int
"""
self._client = Client(host=host, port=port, decode_responses=True)
def keys(self) -> Json:
"""Get all keys"""
return self._client.keys()
def post(self, key: str, obj: Json) -> None:
"""Post a new Json object to the store.
:param key: The key to store the Json at.
:type key: str
:param obj: What to store.
:type obj: Json
"""
self._client.jsonset(key, Path.rootPath(), obj)
def get(self, key: str) -> Json:
"""[summary]
:param key: The key that the Json object was stored at.
:type key: str
:return: The Json stored at `key`.
:rtype: Json
"""
return self._client.jsonget(key, Path.rootPath())
def update(self, key: str, path: str, value: Json) -> None:
"""[summary]
:param key: The key that the Json object was stored at.
:type key: str
:param path: A period seperated string of keys to traverse the Json.
:type path: str
:param value: The new value.
:type value: Json
"""
self._client.jsonset(key, Path(f".{path}"), value)
def append(self, key: str, path: str, *values: Json) -> None:
"""Append to some array within a Json obejct.
:param key: The key that the Json object was stored at.
:type key: str
:param path: A period seperated string of keys to traverse the Json.
:type path: str
"""
self._client.jsonarrappend(key, Path(f".{path}"), *values)
def pop(self, key: str, path: str) -> Json:
"""Pop from from array within a Json object.
:param key: The key that the Json object was stored at.
:type key: str
:param path: A period seperated string of keys to traverse the Json.
:type path: str
:return: The Json value popped from the array.
:rtype: Json
"""
return self._client.jsonarrpop(key, f".{path}")
def remove(self, key: str, path: str, value: Json) -> None:
"""Remove something from some array within a Json object.
:param key: The key that the Json object was stored at.
:type key: str
:param path: A period seperated string of keys to travers the Json.
:type path: str
:param value: The value to remove from the array.
:type value: Json
"""
index = self._client.jsonarrindex(key, f".{path}", value)
self._client.jsondel(key, f"{path}[{index}]")
class RedisJson:
def __init__(self):
self._rjson = Client(host='localhost',
port=6379,
decode_responses=True)
self._root_path = Path.rootPath()
'''
Insert JSON into db
Structure of JSON to insert:
{
'lat' : 80.844,
'long' : -43.139,
'resources' : {
'mask' : 450,
'vaccine' : 56,
'oxygen' : 800,
...
},
'updated' : <unix time ms>
}
'''
def insert(self, key, data):
self._rjson.jsonset(key, self._root_path, data)
'''
Return list of all JSON objects stored in db
TODO: added this for now, but loading everything in memory doesn't seem
like a great idea, maybe RedisSearch will help with this. Or maybe make
this return a generator which can be iterated through
'''
def get(self):
results = []
for key in self._rjson.scan_iter():
results.append(self._rjson.jsonget(key, self._root_path))
return results
'''
Update field of a JSON object in db
Syntax for `path` argument:
E.g. we have {
'key1' : value1,
'key2' : {
'key3' : value2
}
}
To update value2, `path` should be ".key2.key3"
'''
def update(self, key, path, new_value):
self._rjson.jsonset(key, path, new_value)
'''
Delete a JSON value from the db
'''
def delete(self, key):
self._rjson.jsondel(key, self._root_path)
'arr': [None, True, 3.14],
'truth': {
'coord': 'out there'
}
}
jsondata = json.dumps(obj)
rj.jsonset('obj', Path('A2AA'), obj)
# Get something
temp = rj.jsonget('obj', Path('A2AA.truth.coord'))
print (f'Is there anybody... {temp}?')
# Delete something (or perhaps nothing), append something and pop it
rj.jsondel('obj', Path('.arr[0]'))
rj.jsonarrappend('obj', Path('.arr'), 'something')
popped = rj.jsonarrpop('obj', Path('.arr'))
print(f'{popped} popped!')
# Update something else
rj.jsonset('obj', Path('.answer'), 2.17)
# And use just like the regular redis-py client
jp = rj.pipeline()
jp.set('foo', 'bar')
jp.jsonset('baz', Path.rootPath(), 'qaz')
jp.execute()
class RejsonDb(KeyValueStorage):
def __init__(self, conf):
"""
arguments:
conf -- a dictionary containing 'settings' module compatible configuration of the plug-in
"""
self._host = conf['host']
self._port = int(conf['port'])
self._db = int(conf['id'])
self.redis = Client(host=self._host,
port=self._port,
db=self._db,
decode_responses=True)
self._scan_chunk_size = 50
try:
self.redis.jsonget('-')
except ResponseError as e:
if 'unknown command' in str(e):
logging.fatal(
"Rejson DB Plug-in requires Redis with RedisJSON module enabled"
)
else:
raise e
def rename(self, key, new_key):
return self.redis.rename(key, new_key)
def list_get(self, key, from_idx=0, to_idx=-1):
"""
Returns a stored list. If there is a non-list value stored with the passed key
then TypeError is raised.
arguments:
key -- data access key
from_idx -- optional start index
to_idx -- optional (default is -1) end index (including, i.e. unlike Python);
negative values are supported (-1 = last, -2 = penultimate,...)
"""
data = self.get(key, [])
if isinstance(data, list):
if to_idx == -1:
return data[from_idx:]
return data[from_idx:to_idx + 1]
raise TypeError('Object is not a list')
def list_append(self, key, value):
"""
Add a value at the end of a list
arguments:
key -- data access key
value -- value to be pushed
"""
if not self.exists(key):
self.set(key, [])
self.redis.jsonarrappend(key, Path.rootPath(), value)
def list_pop(self, key):
"""
Removes and returns the first element of the list stored at key.
arguments:
key -- list access key
"""
return self.redis.jsonarrpop(key)
def list_len(self, key):
"""
Returns length of a list. If there is a non-list value stored with the passed key
then TypeError is raised.
arguments:
key -- data access key
"""
if not self.exists(key):
return 0
return self.redis.jsonarrlen(key)
def list_set(self, key, idx, value):
"""
Sets the list element at index to value
arguments:
key -- list access key
idx -- a zero based index where the set should be performed
value -- a JSON-serializable value to be inserted
"""
# TODO the operation pair should be atomic to avoid possible race conditions
self.redis.jsonarrpop(key, Path.rootPath(), idx)
return self.redis.jsonarrinsert(key, Path.rootPath(), idx, value)
def list_trim(self, key, keep_left, keep_right):
"""
Trims the list from the beginning to keep_left - 1 and from keep_right to the end.
The function does not return anything.
arguments:
key -- data access key
keep_left -- the first value to be kept
keep_right -- the last value to be kept
"""
self.redis.jsonarrtrim(key, Path.rootPath(), keep_left, keep_right)
def hash_get(self, key, field):
"""
Gets a value from a hash table stored under the passed key
arguments:
key -- data access key
field -- hash table entry key
"""
if self.redis.jsontype(key, Path(f'["{field}"]')) is None:
return None
return self.redis.jsonget(key, Path(f'["{field}"]'), no_escape=True)
def hash_set(self, key, field, value):
"""
Puts a value into a hash table stored under the passed key
arguments:
key -- data access key
field -- hash table entry key
value -- a value to be stored
"""
if not self.exists(key):
self.set(key, {})
self.redis.jsonset(key, Path(f'["{field}"]'), value)
def hash_del(self, key, field):
"""
Removes a field from a hash item
arguments:
key -- hash item access key
field -- the field to be deleted
"""
self.redis.jsondel(key, Path(f'["{field}"]'))
def hash_get_all(self, key):
"""
Returns a complete hash object (= Python dict) stored under the passed
key. If the provided key is not present then an empty dict is returned.
arguments:
key -- data access key
"""
return self.get(key)
def get(self, key, default=None):
"""
Gets a value stored with passed key and returns its JSON decoded form.
arguments:
key -- data access key
default -- a value to be returned in case there is no such key
"""
data = self.redis.jsonget(key, Path.rootPath(), no_escape=True)
if data is None:
return default
return data
def set(self, key, data):
"""
Saves 'data' with 'key'.
arguments:
key -- an access key
data -- a dictionary containing data to be saved
"""
self.redis.jsonset(key, Path.rootPath(), data)
def set_ttl(self, key, ttl):
"""
Set auto expiration timeout in seconds.
arguments:
key -- data access key
ttl -- number of seconds to wait before the value is removed
(please note that update actions reset the timer to zero)
"""
self.redis.expire(key, ttl)
def get_ttl(self, key):
return self.redis.ttl(key)
def clear_ttl(self, key):
self.redis.persist(key)
def remove(self, key):
"""
Removes a value specified by a key
arguments:
key -- key of the data to be removed
"""
self.redis.jsondel(key)
def exists(self, key):
"""
Tests whether there is a value with the specified key
arguments:
key -- the key to be tested
returns:
boolean value
"""
return self.redis.exists(key)
def setnx(self, key, value):
"""
An atomic operation "set if not exists".
returns:
1 if the key was set
0 if the key was not set
"""
return self.redis.jsonset(key, Path.rootPath(), value, nx=True)
def getset(self, key, value):
"""
An atomic operation which obtains current key first and then
sets a new value under that key
returns:
previous key if any or None
"""
data = self.get(key)
self.set(key, value)
return data
def incr(self, key, amount=1):
"""
Increments the value of 'key' by 'amount'. If no key exists,
the value will be initialized as 'amount'
"""
if not self.exists(key):
self.set(key, 0)
return self.redis.jsonnumincrby(key, Path.rootPath(), amount)
def hash_set_map(self, key, mapping):
"""
Set key to value within hash 'name' for each corresponding
key and value from the 'mapping' dict.
Before setting, the values are json-serialized
"""
return self.set(key, mapping)