2.1.2

CHANGES:

Fixes:

• Improve error reporting when failing to load a driver (#115).
• Fix validation of dead connection in postgresql driver (#119 by Sam
  Tombury).
• Tolerate exceptions from pool resource allocators (#116 reported by Ryan
  Moore).
• Fix install script for the caqti.opam package to work with caqti.plugin.
• Fix the announced license exception in the caqti-driver-pgx package.

Dependency updates:

• Update to tls >= 1.0.0 for caqti-mirage (#120 by Hannes Mehnert).
• Update tls-eio to >= 0.17.4 for caqti-tls-eio (to eliminate a hack).
• Update async_kernel to >= v0.17.0 and tcpip to >= 8.1.0 (due to
  resolving deprecations for future compatibility).

2.1.1

CHANGES:

This minor update fixes running of the test suite and packaging issues.

2.1.0

CHANGES:

• There is now TLS support for PGX. The networking code (for PGX) was
  revised in the process, in particular the EIO variant is now buffered,
  which improves performarce. TLS implemantions are shipped as separate
  packages (caqti-tls*) but caqti-tls-async, caqti-tls-eio, and
  caqti-tls-lwt should be considered experimental and will be omitted
  from the OPAM release for now. On the other hand, caqti-mirage now
  ships with built-in TLS support for PGX.

• Connect functions now accept an optional configuration. For the time
  being, this is used for TLS parameters and for the optional
  tweaks_version argument, which is still available for backwards
  compatibility.

• The newly introduced Caqti_query.qprintf and associated formatters
  have been moved to a separate module Caqti_query_fmt (#108), to limit
  clashes when used in local open, and since the formatters were nominally
  underqualified.

• Constants of any field type can now be embedded in queries using the new
  Caqti_query.V constructor and associated shortcuts. This allows
  taking advantage of driver-specific encoders, e.g. to correctly convert
  a Ptime.Span.t to the representation expected by the target database
  system.

• Equality with type unification evidence is now available for
  Caqti_type.t and Caqti_type.Field.t. The equality type introduced
  for the purpose is compatible with Type.eq from OCaml 5.1, but will
  not be aliased yet. This required a backwards incompatible adjustment
  of the Caqti_type.Product constructor.

• Added tuples type constructors with arity up to 12.

• Added multi-statement parser (Caqti_query.angstrom_list_parser)
  intended for loading SQL schema files.

• The new caqti.plugin sublibrary is a drop-in replacement for the
  caqti-dynload package. It is based on the dune-site.plugin library.
  Please try it and report back if there are issues.

• Some updates to external dependencies, esp. we are now at EIO 0.12+.

• Fixed lacking details in error messages related to driver load failures.

• Fixed uncaught exceptions for PGX (#113).

2.0.1

CHANGES:

Fixes:

• Upgrade Eio to 0.11.
• Update README and make a note about caqti-eio and caqti-mirage being
  experimental.
• Fix build and packaging issues.

This release was sponsored by the OCaml Software Foundation.

2.0.0

CHANGES:

New features:

• Added driver based on the pure-OCaml PGX library (#38). However, due to
  lack of TLS support it is not suitable for production, unless you have a
  dedicated secure network.

• Added support for MirageOS. This only works for the PGX driver, since
  the other drivers link against external C libraries.

• Added experimental support for Eio, both pure-OCaml and Unix. The
  former supports PGX while the latter supports all drivers.

• Implemented single-row mode for PostgreSQL (#24), but while this avoids
  uncontrolled memory consumption when a large number of rows is returned,
  it is a lot less efficient.

• A new pool connection parameter ?max_idle_age provides removal
  resources from pools which have been unused for the given period.

• Printf-style function Caqti_query.qprintf for dynamic queries
  (GPR#103, Basile Clément).

• Added general-purpose product type to provide functionality covering
  both product and custom types.

• Added new tuple types t3, ..., t8 based on the new product type and
  deprecated tup2, tup3, tup4 which are now aliases for these.

Breaking changes:

• The minimal OCaml requirement is now 4.08.0.

• The connection functions previously found in caqti-lwt has been moved
  into a sublibrary caqti-lwt.unix as part of the addition of
  caqti-mirage, whereas shared functionality remains in caqti-lwt.
  The LWT connection function is therefore now found in Caqti_lwt_unix.

• Removed all deprecated functionality and a few unintended or
  undocumented definitions like the type Caqti_blocking.future and
  Caqti_driver_info.describe_has_typed_*.

• Reworked the driver API to accommodate the addition of the PGX driver
  and MirageOS and Eio support, and to avoid exposting internal interfaces
  in the main library. These modules are now found in the sublibraries
  caqti.platform and caqti.platform.unix, depending on their external
  depnedencies. They are not meant for use by applications, though this
  might not have fully clear previously.

• Removed constructors Custom, Unit, Tup2, Tup3, Tup4 from Caqti_type.t.
  They were private but could in prinicle be matched against.

• The extensibility of Caqti_type.Field.t has been dropped along with
  the associated functions for registering conversions. This means that
  there are no custom field types any more, only custom row types. The
  purpose of custom field types where to support non-standard types for
  3rd party drivers; we should coordinate additions to the core type
  instead if needed.

• According to the above point, the caqti-type-calendar is reimplemented
  as a row type, which means the Cdate and Ctime constructors are
  gone.

• There are adjustments for the pretty printer for types. (The context is
  assumed to start at the lowest precedence, meaning parentheses around
  lowest-precedence expressions are dropped. Also, redacted is shown
  with suffix notation, allowing us to remove one precedence level.)

• Moved pool tuning parameters into a configuration object.

Fixes:

• Fixed a missing Preemptive.detach call for to_stream for Sqlite3.

• Incorrect error reporting related to type conversions were discovered by
  exhaustiveness checks when making field types non-extensible.

Other:

• The documentation of call now makes clear that the result must be
  retrieved in order to make sure the request is performed. This is made
  relevant by the addition of the PGX driver where request and retrieval
  are fused.

• Customized the top-level index and some other documentation work.
  Removal of private modules from the main library should also help to
  make the documentation more accessible.

• Added a benchmark to measure row decoding performance.

• Improved decoding performance by partially applying the type descriptor.

1.9.1

CHANGES:

This release only updates the caqti-driver-postgresql package, with the
following fixes:

• PostgreSQL expects "=" in query values to be URI-encoded (#95).

• The validation logic for PostgreSQL was missing a call to consume
  available input, meaning that broken pooled connections were reused.

This release was sponsored by the OCaml Software Foundation.

1.9.0

CHANGES:

New features:

• Allow unquoted semicolons in query strings in the new API. There are
  corner cases where it is needed, as reported in issue #87, and a parser
  which rejects semicolons are still available for loading schema files
  statement by statement.

• Add support for MySQL and MariaDB configuration files, as a solution to
  issue #86.

• Add a limit to the number of times a database connection is reused when
  pooling connections (#94). Thanks to Peter Mondlock for investigating
  resource usage server side motivating this addition.

• Provide access to the raw SQLite3 connection handle for the purpose of
  defining custom functions (#56).

Fixes:

• Add missing dune dependency on unix (GPR#85 by David Allsopp).

• Documentation fixes (GPR#82, GPR#83, GPR#84 by Reynir Björnsson,
  GPR#88 by Jonathan Duarte, and GPR#92 by Jim Tittsler).

Deprecations:

• Caqti_type.field was deprecated in favour of Caqti_type.Field.t.

Other:

• Replace deprecated core_kernel dependency with core.

This release was sponsored by the OCaml Software Foundation.

1.8.0

CHANGES:

New features:

• A matchable representation of common causes of errors on the database
  side is now available, with limitations. It focuses on conditions which
  seem most likely useful to handle. At the moment we lack extended error
  codes from SQLite3 needed to make the cause fully precise.

• Expose the underlying error details from database client libraries.
  This is meant to be use as a last resort, and requires directly linking
  with the relevant drivers.

• A second set of request construction operators ->., ->?, ->!, and
  ->* were introduced after experience with converting existing code.
  Given the parameter and result type they return a function which
  constructs a request directly from a query string. Avoiding the need to
  compose with @:- simplifies local opens and usage with List.map etc.

• Environment variables are now expanded in the debug log when using the
  new request constructors introduced in 1.7.0.

• A new ?tweaks_version connection parameter has been added to control
  when the client is ready to adapt to changes in database session
  parameters or other adjustments of the interaction with specific
  database systems.

• Enable foreign key constraint checks for SQLite3 starting at tweaks
  version 1.8.

Fixes:

• Fixed debug logging to pass the correct driver info to the query
  callback instead of a dummy driver info which would cause a failure if
  unsupported.

Deprecations:

• The --> operator was renamed to -->!, with a deprecated alias, for
  consistency with the new ->! operator.

• The old convenience interface for creating requests has been deprecated
  in favour of the new infix operators and the new query template parser.

• Documented-only deprecations of Caqti_sql_io, Caqti_lwt_sql_io, and
  Caqti_async_sql_io have been annotated.

This release was sponsored by the OCaml Software Foundation.

1.7.0

CHANGES:

New features:

• Added a new query-string parser based on Angstrom. Its main advantage
  is that it can be used stand-alone e.g. to load SQL schemas from files
  split into individual statements which can be sent to the database.

• Support passing a query environment to the connect and pool construction
  functions. This avoids using globals to modify the environment and
  facilitates e.g. targeting different database schemas with different
  connetions or connection pools.

• A new Caqti_query.E case was added to support the two above cases.
  This is a breaking change, but hopefully does not break existing code.
  The exception (not counting module type of) would be if the
  constructors are aliased along with an alias of the type. On the other
  hand, pattern matching should be compatible since the new constructor is
  only emitted by newly introduced functions.

• Added a module Caqti_request.Infix providing a new high-level API for
  constructing requests. It uses two-stage combinators, first to apply
  type arguments then to apply the query string. Apart from allowing
  nicer looking code, this solves the problem of switching to a the query
  string parser while maintaining backwards compatibility.

• Added set_statement_timeout to connection modules, used to set query
  timeout. It is only supported for PostgreSQL and MariaDB. (#74)

• Added with_transaction function to connection modules. This is just
  fail-safed wrapper around start, commit, and rollback.

Fixes:

• Fixed delayed recovery of connection pools after loosing connections to
  PostgreSQL. Due to a missing call to consume inputs, the pool validator
  did not discover that a connection was lost before it was attempted
  reused.

• Improved resilience against exceptions and monadic errors in callbacks
  and fixed in-use checking.

• Changed Sqlite3 driver to use non-linear parameters and improve error
  reporting when the wrong number of arguments are received (#77 & GPR#79
  Reynir Björnsson).

Other changes:

• The Caqti license now uses the LGPL-3.0 Linking Exception instead of a
  rephrasing of the OCaml LGPL Linking Exception which was written for
  LGPL-2.1.

• Improved documentation, pretty-printing, logging, and exception details.

• The test suite has been switched to use Alcotest; not without some
  struggle due to the use of test harness and argument-dependent test
  suite, but the result seems like a clear improvement.

This release was sponsored by the OCaml Software Foundation.

v1.6.0

CHANGES:

• Set the time zone of PostgreSQL connections to UTC to mitigate an
  undesirable implicit conversion to the local time zone for timestamp.
  This issue was exposed by the specification of field types introduced in
  version 1.4.0. Earlier versions worked as expected, if only accidentally,
  since the time zone is ignored when a string is converted to a
  timestamp. While this change makes timestamp more usable again for
  storing UTC time stamps, I strongly recommend using timestamp with time zone since it's interpretation is unambiguous. The API reference is now
  updated with details about how the ptime OCaml type is mapped for
  different database systems.
• Drop specification of OCaml string as SQL text for PostgreSQL. This is
  due to issues with implicit conversions and function overloading when the
  desired type on the SQL side is char, varchar, or jsonb.
• Add Caqti_type.redact to protect sensitive information from being
  logged.
• Only log parameters if $CAQTI_DEBUG_PARAM is set to "true".
• When logging requests, show underlying values for custom types.
• Reject multi-row response in find_opt implementation for sqlite3.
• Tolerate Lwt promise rejections in Pool.use.