4.4 Changelog

Driver Migration Guide

Please read our Driver Migration Guide for guidance and breaking changes when migrating from 1.7 drivers to 4.X drivers.

Changelog

4.4.8

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🔧 Fixes

• Fix connection pool clogging up when checking if new connections can be created while the pool is full (#803; fixes #796).
• Fix string representation of neo4j.exceptions.ClientError and neo4j.exceptions.Neo4jError when raised from the driver code (805).

4.4.7

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🔧 Fixes

• Fix DeprecationWarning for update_routing_table_timeout config option being emitted if the option was not used (#789).
• Fix relying on garbage collector to close sockets under certain failure conditions (#794).

4.4.6

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🔧 Fixes

• Fix method accidentally marked async (#774).

👏 Improvements

• Speed up DateTime.to_clock_time by 2 orders of magnitude and with it the serialization of DateTime objects (#781).

🧹Clean-up

• ⚠️ Deprecate timeout config options introduced in 4.4.5 (#768).
  update_routing_table_timeout and session_connection_timeout have been deprecated and will be removed in 5.0.
  Server-side keep-alives communicated through configuration hints together with connection_acquisition_timeout are sufficient to avoid the driver getting stuck.

4.4.5

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🔧 Fixes

• Implement patched protocol that removes ambiguity in datetimes with named zone. For this to take effect, the server needs to be at least on patch version 4.3.18 or 4.4.11 respectively.

👏 Improvements

• Clarify the documentation around session.read_transaction: it does not enforce access control (#753).
• Multiple improvements around timeouts (#746):
  • The configuration option connection_acquisition_timeout does only limit the amount of time the driver waits for a connection from the pool. It does not cater for potential routing table updates. Therefore, two new configuration options update_routing_table_timeout and session_connection_timeout are being introduced. Read more about them in the API docs .
  • A slow response from the server while opening a new connection does no longer block the whole connection pool.

4.4.4

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🔧 Fixes

• Fix pool closing connections that are in use when opening a new connection fails (#733). Especially, but not only, in concurrent contexts, this would lead to all sorts of unspecific errors.
• Fix pool trying to close the same connection multiple times if closing fails. (#733). This would lead to ValueError: deque.remove(x): x not in deque (Issue #739).

👏 Improvements

• Performance improvement around logging calls (even with disabled logging) (#726).
• Several small improvements to docstrings and API docs.

4.4.3

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🔧 Fixes

• Fix wrong serialization of the DateTime type's timezone (#684).
• Fix wrong comparison operators of several types in the neo4j.time package (#684).
• Improve compatibility of neo4j.time with different timezone implementations (#684).

4.4.2

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🔧 Fixes

• Fix the driver sending partial data (causing connection closure and hence slightly worse performance) on errors during data serialization (#641).

⭐ New Features

• Backported (experimental) preview of pandas DataFrame export for results. (#678). Note: the change is self-contained and does not affect any other parts of the driver.

4.4.1

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🔧 Fixes

• Fix pool closing stale connections that are in use (#631). Especially, but not only, in concurrent contexts, this would lead to all sorts of unspecific errors.

👏 Improvements

• Performance improvement when packing data (#622).

4.4.0

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🔧 Fixes

• Fail fast and raise the original error during discovery (initial attempt to connect to the server) on certain errors that are expected to be experienced across all cluster-members ,e.g., Neo.ClientError.Database.DatabaseNotFound and Neo.ClientError.Transaction.InvalidBookmark(#611).
• Fix wrong serialization of the Time type's timezone (#616).

4.4.0b1

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🔧 Fixes

• Use selectors.DefaultSelector instead of select.select which resolves the number of simultaneously open files (including sockets) being limited to 1024 on all operating systems that support it (#604).
• Fixed AttributeError on connection clean-up (#603).

👏 Improvements

• Log the reason when a secure connection could not be established (#608).

4.4.0a1

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⭐ New Features

• Introduce impersonation support (#599).
• Add bearer authentication support (single sign-on) (#579).
• Add Bolt 4.4 support (#560).

🔧 Fixes

• Time types use Decimals and integers instead of floats for sub-seconds (#551).
  This fixes rounding issues and allows for an exact representation of nanoseconds, but comes at the cost of a slightly altered API. Please refer to the documentation.

👏 Improvements

• Fail fast on transaction begin (#586).
• Only send qid parameter over the wire when necessary (#585).
• Reduce the number of RESET messages send over the wire to the bare minimum (#572).
• Fail fast on re-using a broken transaction (#566).

🧹Clean-up

• Drop support for Python 3.5 (end of life 2020-11-13) (#560).