diff --git a/synapse/streams/config.py b/synapse/streams/config.py
index 69c7145a36..2434844d80 100644
--- a/synapse/streams/config.py
+++ b/synapse/streams/config.py
@@ -26,40 +26,53 @@ class PaginationConfig(object):
"""A configuration object which stores pagination parameters."""
- def __init__(self, from_tok=None, to_tok=None, direction='f', limit=0):
- self.from_token = (
- StreamToken.from_string(from_tok) if from_tok else None
- )
- self.to_token = StreamToken.from_string(to_tok) if to_tok else None
+ def __init__(self, from_token=None, to_token=None, direction='f',
+ limit=0):
+ self.from_token = from_token
+ self.to_token = to_token
self.direction = 'f' if direction == 'f' else 'b'
self.limit = int(limit)
@classmethod
def from_request(cls, request, raise_invalid_params=True):
- params = {
- "direction": 'f',
- }
-
- query_param_mappings = [ # 3-tuple of qp_key, attribute, rules
- ("from", "from_tok", lambda x: type(x) == str),
- ("to", "to_tok", lambda x: type(x) == str),
- ("limit", "limit", lambda x: x.isdigit()),
- ("dir", "direction", lambda x: x == 'f' or x == 'b'),
- ]
-
- for qp, attr, is_valid in query_param_mappings:
- if qp in request.args:
- if is_valid(request.args[qp][0]):
- params[attr] = request.args[qp][0]
- elif raise_invalid_params:
- raise SynapseError(400, "%s parameter is invalid." % qp)
-
- if "from_tok" in params and params["from_tok"] == "END":
- # TODO (erikj): This is for compatibility only.
- del params["from_tok"]
+ def get_param(name, default=None):
+ lst = request.args.get(name, [])
+ if len(lst) > 1:
+ raise SynapseError(
+ 400, "%s must be specified only once" % (name,)
+ )
+ elif len(lst) == 1:
+ return lst[0]
+ else:
+ return default
+
+ direction = get_param("dir", 'f')
+ if direction not in ['f', 'b']:
+ raise SynapseError(400, "'dir' parameter is invalid.")
+
+ from_tok = get_param("from")
+ to_tok = get_param("to")
+
+ try:
+ if from_tok == "END":
+ from_tok = None # For backwards compat.
+ elif from_tok:
+ from_tok = StreamToken.from_string(from_tok)
+ except:
+ raise SynapseError(400, "'from' paramater is invalid")
+
+ try:
+ if to_tok:
+ to_tok = StreamToken.from_string(to_tok)
+ except:
+ raise SynapseError(400, "'to' paramater is invalid")
+
+ limit = get_param("limit", "0")
+ if not limit.isdigit():
+ raise SynapseError(400, "'limit' parameter must be an integer.")
try:
- return PaginationConfig(**params)
+ return PaginationConfig(from_tok, to_tok, direction, limit)
except:
logger.exception("Failed to create pagination config")
raise SynapseError(400, "Invalid request.")
|
