instream

# Changelog

## v0.19.0 (2019-01-24)

- Enhancements
    - Connections can be declared with compile time configuration defaults that are later overwritten by the application environment
    - The library used for JSON decoding can be changed by using the `:json_decoder` configuration

- Soft deprecations (no warnings)
    - All "administrative query modules" have been removed from the documentation. They will eventually be removed completely after a proper deprecation phase
    - Support for `{:system, "ENV_VARIABLE"}` configuration has been removed from the documentation. It will eventually be removed completely after a proper deprecation phase

- Backwards incompatible changes
    - Default configuration has been extended with `host: "localhost"`
    - Minimum required elixir version is now `~> 1.5`
    - Missing application configuration will no longer raise during compilation
    - Public access to the internal pool module name has been removed

## v0.18.0 (2018-08-11)

- Enhancements
    - Configuration can be done on connection (re-) start by setting a `{mod, fun}` tuple for the config key `:init`. This method will be called with the connection module name as the first (and only) parameter and is expected to return `:ok`
    - Experimental support to convert plain maps or query results into series structs has been added
    - Passwords are automatically redacted from logged queries when using the default logger
    - Supporting rules for the elixir formatter are available

- Bug fixes
    - Special characters in url parameter values (like `&` or `?` in a query) are now properly escaped ([#43](https://github.com/mneudert/instream/pull/43))

- Backwards incompatible changes
    - Quoting of identifiers/values has been extracted to the package `influxql` ([hex](https://hex.pm/packages/influxql))

## v0.17.1 (2017-12-16)

- Enhancements
    - Support for Elixir 1.5 style `child_spec` has been added ([#39](https://github.com/mneudert/instream/pull/39))

## v0.17.0 (2017-12-10)

- Backwards incompatible changes
    - Minimum required elixir version is now `~> 1.3`

## v0.16.0 (2017-09-25)

- Enhancements
    - Queries can be executed with an additional option `:pool_timeout` used to wait for an available worker process. This option is independent of other configured/passed timeouts
    - System environment configuration can set an optional default value to be used if the environment variable is unset

- Bug fixes
    - All queries now use a `GenServer.call/3` timeout of `:infinity`. This allows raising the timeouts for a call above the default of `5_000` ([#38](https://github.com/mneudert/instream/issues/38))

## v0.15.0 (2017-03-16)

- Enhancements
    - Every connection method (like `read` or `write`) can set per-call `http_opts` passed on to the `hackney` client
    - Querying for data can now return an `{:error, term}` style tuple if the communication with the server failed. For example `{:error, :nxdomain}` if the host that is queried cannot be resolved by `hackney` ([#33](https://github.com/mneudert/instream/issues/33))
    - The line writer now accepts a retention policy used for writing ([#34](https://github.com/mneudert/instream/pull/34))
    - The line writer will now return an `{:error, term}` style tuple if a problem occurs. For example `{:error, :nxdomain}` if the host that should receive data cannot be resolved by `hackney` ([#33](https://github.com/mneudert/instream/issues/33))
    - Timeouts occurring when executing a query are now returned as `{:error, :timeout}` instead of raising ([#33](https://github.com/mneudert/instream/issues/33))

- Backwards incompatible changes
    - Series definitions raise upon compilation if the contain a tag and a field with the same name. This is done to prevent the InfluxDB behavior of adding `_1` to such fields when storing them

## v0.14.0 (2016-12-18)

- Enhancements
    - Connections can be configured with a default database used when no value is found in method call or series definition
    - Fields and tags with the name `:time` will raise after compilation. They are unqueryable and will be dropped by InfluxDB v1.1.0 when trying to write them.
    - Queries can return CSV formatted responses from the server when running InfluxDB >= 1.1.0
    - Series definitions are now automatically associated with typespecs

- Backwards incompatible changes
    - Minimum required elixir version is now `~> 1.2`
    - Minimum required erlang version is now `~> 18.0`
    - Query builder support for `IF NOT EXISTS` has been removed
    - Series definitions now require to contain at least one field

- Soft deprecations (no warnings)
    - The plural names for precision units have been soft deprecated to be in line with the similar new naming in `Erlang 19.1` and the upcoming `Elixir 1.4.0`. The old types will continue to work but their usage is discouraged. They will be completely deprecated in an upcoming release.

## v0.13.0 (2016-09-11)

- Enhancements
    - Configuration has been split into "compile time" and "runtime" parts. This readds the possibility to change configuration values without recompiling the connection modules ([#22](https://github.com/mneudert/instream/pull/22))
    - Configuration values can be fetched from the system environment using `{:system, ENV_VAR}`
    - Timeouts for queries (individual and connection wide) can be configured ([#21](https://github.com/mneudert/instream/pull/21))
    - Query builder supports `LIMIT` and `OFFSET` for queries ([#19](https://github.com/mneudert/instream/pull/19))
    - Writing a series struct with one or more empty tags will now properly construct an entry without these tags present

- Soft deprecations (no warnings)
    - The precision units `:micro_seconds`, `:milli_seconds` and `:nano_seconds` have been renamed to `:microseconds`, `:milliseconds` and `:nanoseconds` to matches the upcoming `System.time_unit` definition of `Elixir 1.3.0`. Old variables will continue to work but are highly discouraged and will be completely deprecated in an upcoming release.

- Deprecations
    - Defining a series without fields is deprecated and will raise in a future version

- Backwards incompatible changes
    - Configuring a connection with multiple hosts is no longer supported
    - The otp app of a connection is no longer returned when calling `MyConnection.config/0,1`. It is now only available by specifically requesting it via `MyConnection.config([:otp_app])`
    - Writer modules now get a map passed with the connection module registered at key `:module` and (if configured) a udp socket for writing at `:udp_socket`
    - The `Cluster` namespace of queries has been removed

## v0.12.0 (2016-05-13)

- Enhancements
    - Namespace of administrational convenience modules has been changed from `Cluster` to the better matching `Admin`

- Deprecations
    - Configuring a connection with multiple hosts has been deprecated. Instead of multiple `:hosts` only a single `:host` is now expected
    - The `Cluster` namespace of queries has been changed to `Admin`. For some backwards compatibility the old modules are delegated to the new ones until removed in the next release

- Backwards incompatible changes
    - Atoms for defining a series' database are no longer supported
    - Atoms for defining a series' measurement are no longer supported
    - Support for the JSON protocol has been removed matching its removal in InfluxDB v0.12.0
    - Support for the `SHOW SERVERS` statement has been removed matching its removal in InfluxDB v0.13.0

## v0.11.0 (2016-04-14)

- Enhancements
    - Hackney options can be configured ([#17](https://github.com/mneudert/instream/pull/17))
    - Line writer now prefers a database passed via arguments over the one passed in the datapoint payload
    - Logging for requests is available
    - Pings can be send to specific servers
    - Status requests can be send to a cluster

- Bug fixes
    - Series are now compiled with full environment information preventing "/path/to/lib/nofile" to be compiled as the source of `MySeries.Fields` or `MySeries.Tags`

- Backwards incompatible changes
    - Runtime connection configuration reading has been removed in favor of compile time inlining

## v0.10.0 (2016-02-27)

- Enhancements
    - Default precision (`:rfc3339`) can be explicitly set
    - Query builder can construct `CREATE DATABASE` statements
    - Query builder can construct `CREATE RETENTION POLICY` statements
    - Query builder can construct `DROP DATABASE` statements
    - Query builder can construct `DROP RETENTION POLICY` statements
    - Query builder can construct `SHOW` statements
    - Series database definitions allow anything "evaluating to a string" ([#14](https://github.com/mneudert/instream/pull/14))
    - Series measurement definitions allow anything "evaluating to a string" ([#14](https://github.com/mneudert/instream/pull/14))

- Deprecations
    - Atoms for defining a series' database are deprecated
    - Atoms for defining a series' measurement are deprecated
    - Using `if_not_exists` (`CREATE DATABASE`) has been deprecated and will be completely removed once InfluxDB removes it

- Backwards incompatible changes
    - `:cluster` query type has been removed in favor of regular `:read` queries
    - Retention policy convenience function has been replaced with a more detailed version

## v0.9.0 (2015-12-27)

- Enhancements
    - Error messages are returned without leading/trailing whitespace
    - Experimental query builder
    - Incomplete or missing series definitions raise an error during compilation
    - Ping a connection using `Instream.Connection.ping/0`
    - Reading queries can be executed directly using `Instream.Connection.query/2`
    - Writing query can be executed directly using `Insream.Connection.write/2`

- Deprecations
    - Using `Instream.Data.Read` or `Instream.Data.Write` directly is discouraged and will eventually be removed

- Backwards incompatible changes
    - The measurement of a series is no longer optional
    - The parameter `opts` for `Instream.Data.Read` and `Instream.Data.Write` is no longer optional
    - `use`-ing `Instream.Series` without a complete series definition raises during compilation

## v0.8.0 (2015-11-18)

- Enhancements
    - Batch writing using `Line` and `UDP` writers ([#10](https://github.com/mneudert/instream/pull/10))
    - Fields can be defined with default values
    - Tags can be defined with default values
    - Writing can be done over UDP using `Instream.Writer.UDP`

## v0.7.0 (2015-10-22)

- Enhancements
    - Convenience module for "SHOW DIAGNOSTICS" queries
    - Convenience module for "SHOW STATS" queries
    - Precision (= epoch) can be passed to read queries
    - Precision can be passed to write queries

- Bug fixes
    - Pool configuration (size, overflow) is now properly taken from configuration

- Deprecations
    - Support of the JSON protocol is deprecated and will be removed once InfluxDB removes it

## v0.6.0 (2015-09-27)

- Enhancements
    - `IF NOT EXISTS` can be passed to database creation queries
    - Points can be written with explicit timestamps ([#8](https://github.com/mneudert/instream/pull/8))
    - Switched default write method to the line protocol
    - Tags are optional when writing with the line protocol

- Backwards incompatible changes
    - Switched default write method to the line protocol

## v0.5.0 (2015-09-05)

- Enhancements
    - Convenience module for `SHOW SERVERS` queries
    - Queries can be executed asynchronously
    - Support for line protocol

- Backwards incompatible changes
    - Write queries return `:ok` instead of `nil`

## v0.4.0 (2015-07-25)

- Enhancements
    - Allows using header authentication (basic auth)
    - Allows using pre-defined series modules for write queries
    - Provides a way to define series as a module (struct)

- Backwards incompatible changes
    - Authentication uses headers by default

## v0.3.0 (2015-06-19)

- Enhancements
    - Allows managing retention policies
    - Dependencies not used in production builds are marked as optional

- Bug fixes
    - Authentication is passed using query parameters by default

- Backwards incompatible changes
    - Auth configuration is now expected to be a `Keyword.t`
    - Queries of type `:host` are now of type `:cluster`
    - Remapped `Admin` namespace to `Cluster` to match query types

## v0.2.0 (2015-04-19)

- Enhancements
    - Allows accessing raw query results (undecoded binaries) using `Instream.Connection.execute/2`
    - Read queries (binaries) can be executed on a database
    - Write queries (map data) can be executed on a database

## v0.1.0 (2015-02-23)

- Initial Release