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0.14

Signifacant changes

• Stream takes a status code argument

  -Stream method        framing ctype a
  +Stream method status framing ctype a
  

  (#966 #972)

• ToStreamGenerator definition changed, so it's possible to write an instance for conduits.

  -class ToStreamGenerator f a where
  -   toStreamGenerator :: f a -> StreamGenerator a
  +class ToStreamGenerator a b | a -> b where
  +   toStreamGenerator :: a -> StreamGenerator b
  

  (#959)

• Added NoFraming streaming strategy (#959)

• servant-client-core Free Client implementation. Useful for testing HasClient instances. (#920)

• servant-client-core Add hoistClient to HasClient. Just like hoistServer allows us to change the monad in which request handlers of a web application live in, we also have hoistClient for changing the monad in which client functions live. Read tutorial section for more information. (#936)

  iF you have own combinators, you'll need to define a new method of HasClient class, for example:

  type Client m (MyCombinator :> api) = MyValue :> Client m api
  hoistClientMonad pm _ nt cl = hoistClientMonad pm (Proxy :: Proxy api) nt . cl
  

• servant Add safeLink' :: (Link -> a) -> ... -> MkLink endpoint a, which allows to create helpers returning something else than Link. (#968)

• servant-server File serving in polymorphic monad. i.e. Generalised types of serveDirectoryFileServer etc functions in Servant.Utils.StaticFiles (#953)

• servant-server ReqBody content type check is recoverable. This allows writing APIs like:

        ReqBody '[JSON] Int      :> Post '[PlainText] Int
  :<|>  ReqBody '[PlainText] Int :> Post '[PlainText] Int
  

  which is useful when handlers are subtly different, for example may do less work. (#937)

• servant-client Add more constructors to RequestBody, including RequestBodyStream. Note: we are looking for http-library agnostic API, so the might change again soon. Tell us which constructors are useful for you! (#913)

Other changes

• GetHeaders instances implemented without OverlappingInstances (#971)

• Added tests or enabled tests (#975)

• Add pagination cookbook recipe (#946)

• Add servant-flatten "spice" to the structuring api recipe (#929)

• Dependency updates (#900 #919 #924 #943 #964 #967 #976)

• Documentation updates #963 #960 #908 #958 #948 #928 #921)

• Development process improvements (#680 #917 #923 #961 #973)

Note

(VIM) Regular-expression to link PR numbers: s/\v#(\d+)/[#\1](https:\/\/github.com\/haskell-servant\/servant/pull\/\1)/

0.13.0.1

• Support base-compat-0.10

0.13

Significant changes

• Streaming endpoint support. (#836)

  type StreamApi f = "streamGetNewline" :> StreamGet NewlineFraming JSON (f Person)
  

  See tutorial for more details

  • A web API as a type - StreamGet and StreamPost
  • Serving an API - streaming endpoints
  • Querying an API - Querying Streaming APIs

• servant Add Servant.API.Modifiers (#873 #903)

  QueryParam, Header and ReqBody understand modifiers:

  • Required or Optional (resulting in a or Maybe a in handlers)
  • Strict or Lenient (resulting in a or Either String a in handlers)

  Also you can use Description as a modifier, but it doesn't yet work with servant-docs, only servant-swagger. There is an issue.

• servant-client Support http-client’s CookieJar (#897 #883)

  ClientM preserves cookies between requests, if given initial CookieJar. To migrate from older code, change ClientEnv constructor to mkClientEnv which makes ClientEnv without CookieJar.

• servant Mono-kind-ise modifiers, resulting in better error messages. (#887 #890)

• servant Add TypeError ... => HasServers instances in GHC-8.2 for not saturated modifiers (Capture "foo" :> ...) or -> in place of :>. (#893)

• Cookbook example projects at http://haskell-servant.readthedocs.io/en/master/cookbook/index.html (#867 #892)

• Experimental work servant-client-ghcjs (#818 #869)

Other changes

• servant Links aren't double escaped (#878)

• Dependency updates (#900 #898 #895 #872)

• Documentation updates (#875 #861)

• Refactorings (#899 #896 #889 #891 #892 #885)

0.12.1

Bug fixes

• Prevent double-escaping in link segments (#835 #878)

0.12

Significant changes

• servant-client servant-client-core Factored out of servant-client all the functionality that was independent of the http-client backend. (#803 #821)

  If you have own combinators, you'll need to add an additional m argument in HasClient, Client and clientWithRoute:

  -class HasClient api
  -  type Client (api :: *) :: *
  -  clientWithRoute :: Proxy api -> Req -> Client api
  +class HasClient m api
  +  type Client (m :: * -> *) (api :: *) :: *
  +  clientWithRoute :: Proxy m -> Proxy api -> Request -> Client m api
  

  See https://github.com/haskell-servant/servant-auth/pull/67/commits/f777818e3cc0fa3ed2346baff8328e96d62b1790 for a real world example.

• servant-server Added hoistServer member to the HasServer class, which is HasServer specific enter. (#804 #824)

  enter isn't exported from Servant module anymore. You can change enter to hoistServer in a straight forward way. Unwrap natural transformation and add a api type Proxy:

  -server = enter (NT nt) impl
  +server = hoistServer (Proxy :: Proxy MyApi) nt impl
  

  If you have own combinators, you'll need to define a new method of HasServer class, for example:

  type ServerT (MyCombinator :> api) m = MyValue -> ServerT api m
  hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt . s
  

  See https://github.com/haskell-servant/servant-auth/pull/67/commits/8ee3b6315247ac076516213fd7cfcdbfdb583ac9 for a real world example.

• Add Description and Summary combinators (#767)

  It's possible to annotate endpoints with free form text. This information is used by e.g. by servant-swagger, see screenshot in https://github.com/phadej/servant-swagger-ui

• Lower :> and :<|> infix precedence to 4 and 3 respectively (#761)

  This shouldn't affect you, except if you define your own infix operators for Servant type-level DSL.

Other changes

• servant-foreign Derive Data for all types (#809)
• servant-docs Add authentication lenses (#787)
• servant-docs Generated markdown improvements (#813 #767 #790 #788)
• Add addLinks to generate all links for unnested APIs. (#851)
• Allow newest dependencies (#772 #842)
• Documentation improvements and typo fixes (#757 #771 #775 #790 #791 #806)
• Development process improvements (#764 #839)

0.11

Breaking changes

• Enter refactored (#734 , #736)

Other changes

• Add a type representing an empty API (#753)
• Add linkURI' and Link accessors (#745 , #717 , #715)
• Prepare for GHC-8.2 (#722)
• Add HasLink AuthProtect instance (#720)
• AllCTRender [] () TypeError (use NoContent) (#671)
• Documentation improvements and typo fixes (#702 , #709 , #716 , #725 , #727)

0.10

Breaking changes

• Use NT from natural-transformation for Enter (#616)

• Change to MkLink (Verb ...) = Link (previously URI). To consume Link use its ToHttpApiData instance or linkURI. (#527)

Other changes

• Add Servant.API.TypeLevel module with type families to work with API types. (#345 , #305)

• Default JSON content type change to application/json;charset=utf-8. (#263) Related browser bugs: Chromium and Firefox

• Accept class may accept multiple content-types. MimeUnrender adopted as well. (#613 , #615)

0.9.1

• Added 'noHeader' function for not adding response headers.

0.9

• Added Eq, Show, Read, Generic and Ord instances to IsSecure
• BACKWARDS INCOMPATIBLE: replace use of ToFromByteString with To/FromHttpApiData for GetHeaders/BuildHeadersTo
• BACKWARDS INCOMPATIBLE: Moved From/ToFormUrlEncoded classes, which were renamed to From/ToForm to http-api-data

0.8.1

• Add CaptureAll combinator. Captures all of the remaining segments in a URL.
• Add Servant.API.TypeLevel module, with frequently used type-level functionaliy.

0.8

• Minor fixes, documentation changes and cabal tweaks

0.7.1

• Add module Servant.Utils.Enter (https://github.com/haskell-servant/servant/pull/478)
• Allow to set the same header multiple times in responses.

0.5

• Add WithNamedConfig combinator.
• Add HttpVersion, IsSecure, RemoteHost and Vault combinators
• Fix safeLink, so Header is not in fact required.
• Add more instances for (:<|>)
• Use http-api-data instead of Servant.Common.Text
• Remove matrix params.
• Add PlainText String MimeRender and MimeUnrender instances.
• Add new Verbs combinator, and make all existing and new verb combinators type synonyms of it.
• Add BasicAuth combinator to support Basic authentication
• Add generalized authentication support

0.4.2

• Fix missing cases for Patch in safeLink

0.4.1

• Allow whitespace after parsing JSON
• Stricter matching for safeLink for Capture

0.4

• Delete now is like Get, Post, Put, and Patch and returns a response body
• Multiple content-type/accept support for all the relevant combinators
• Provide JSON, PlainText, OctetStream and FormUrlEncoded content types out of the box
• Type-safe link generation to API endpoints
• Support for the PATCH HTTP method
• Removed the home-made QuasiQuote for writing API types in a more human-friendly format until we come up with a better design for it
• Make most if not all of the haddock code examples run through doctest
• Some general code cleanup
• Add response headers