minio-hs/docs/API.md

Minio Haskell SDK API Reference

Initialize Minio Client object.

Minio - for public Play server

minioPlayCI :: ConnectInfo
minioPlayCI

AWS S3

awsCI :: ConnectInfo
awsCI { connectAccesskey = "your-access-key"
      , connectSecretkey = "your-secret-key"
      }

Bucket operations	Object Operations
listBuckets	getObject
makeBucket	putObject
removeBucket	fGetObject
listObjects	fPutObject
listIncompleteUploads	copyObject
	removeObject

1. Connecting and running operations on the storage service

The Haskell Minio SDK provides high-level functionality to perform operations on a Minio server or any AWS S3-like API compatible storage service.

The ConnectInfo type

The ConnectInfo record-type contains connection information for a particular server. It is recommended to construct the ConnectInfo value using one of the several smart constructors provided by the library, documented in the following subsections.

The library automatically discovers the region of a bucket by default. This is especially useful with AWS, where buckets may be in different regions. When performing an upload, download or other operation, the library requests the service for the location of a bucket and caches it for subsequent requests.

awsCI :: ConnectInfo

awsCI is a value that provides connection information for AWS S3. Credentials can be supplied by overriding a couple of fields like so:

awsConn = awsCI {
    connectAccessKey = "my-AWS-access-key"
  , connectSecretKey = "my-AWS-secret-key"
  }

awsWithRegionCI :: Region -> Bool -> ConnectInfo

This constructor allows to specify the initial region and a Boolean to enable/disable the automatic region discovery behaviour.

The parameters in the expression awsWithRegion region autoDiscover are:

Parameter	Type	Description
region	Region (alias for Text)	The region to connect to by default for all requests.
autoDiscover	Bool	If True, region discovery will be enabled. If False, discovery is disabled, and all requests go the given region only.

minioPlayCI :: ConnectInfo

This constructor provides connection and authentication information to connect to the public Minio Play server at https://play.minio.io:9000/.

minioCI :: Text -> Int -> Bool -> ConnectInfo

Use to connect to a Minio server.

The parameters in the expression minioCI host port isSecure are:

Parameter	Type	Description
host	Text	Hostname of the Minio or other S3-API compatible server
port	Int	Port number to connect to
isSecure	Bool	Does the server use HTTPS?

The ConnectInfo fields and Default instance

The following table shows the fields in the ConnectInfo record-type:

Field	Type	Description
connectHost	Text	Host name of the server. Defaults to localhost.
connectPort	Int	Port number on which the server listens. Defaults to 9000.
connectAccessKey	Text	Access key to use in authentication. Defaults to minio.
connectSecretkey	Text	Secret key to use in authentication. Defaults to minio123.
connectIsSecure	Bool	Specifies if the server used TLS. Defaults to False
connectRegion	Region (alias for Text)	Specifies the region to use. Defaults to 'us-east-1'
connectAutoDiscoverRegion	Bool	Specifies if the library should automatically discover the region of a bucket. Defaults to True

The def value of type ConnectInfo has all the above default values.

The Minio Monad

This monad provides the required environment to perform requests against a Minio or other S3 API compatible server. It uses the connection information from the ConnectInfo value provided to it. It performs connection pooling, bucket location caching (if enabled) and error handling.

The runMinio function performs the provided action in the Minio monad and returns a ResourceT IO (Either MinioErr a) value:

import Network.Minio

main :: IO ()
main = do
  result <- runResourceT $ runMinio def $ do
    buckets <- listBuckets
    return $ length buckets

  case result of
    Left e -> putStrLn $ "Failed operation with error: " ++ show e
    Right n -> putStrLn $ show n ++ " bucket(s) found."

The above performs a listBuckets operation and returns the number of buckets in the server. If there were any errors, they will be returned as values of type MinioErr as a Left value.

runResourceT takes a value from ResourceT IO a to IO a. It takes care of running finalizers to free resources.

2. Bucket operations

listBuckets :: Minio [BucketInfo]

Lists buckets.

Return Value

Return type	Description
Minio [BucketInfo]	List of buckets

BucketInfo record type

Field	Type	Description
biName	Bucket (alias of Text)	Name of the bucket
biCreationDate	UTCTime	Creation time of the bucket

makeBucket :: Bucket -> Maybe Region -> Minio ()

Create a new bucket. If the region is not specified, the region specified by ConnectInfo is used.

Parameters

In the expression makeBucket bucketName region the arguments are:

Param	Type	Description
bucketName	Bucket (alias for Text)	Name of the bucket
region	Maybe Region	Region where the bucket is to be created. If not specified, default to the region in ConnectInfo.

Example

{-# Language OverloadedStrings #-}
main :: IO ()
main = do
    res <- runResourceT $ runMinio minioPlayCI $ do
        makeBucket bucketName (Just "us-east-1")

    case res of
        Left err -> putStrLn $ "Failed to make bucket: " ++ (show res)
        Right _ -> putStrLn $ "makeBucket successful."

removeBucket :: Bucket -> Minio ()

Remove a bucket. The bucket must be empty or an error will be thrown.

Parameters

In the expression removeBucket bucketName the arguments are:

Param	Type	Description
bucketName	Bucket (alias for Text)	Name of the bucket

Example

{-# Language OverloadedStrings #-}
main :: IO ()
main = do
    res <- runResourceT $ runMinio minioPlayCI $ do
        removeBucket "mybucket"

    case res of
        Left err -> putStrLn $ "Failed to remove bucket: " ++ (show res)
        Right _ -> putStrLn $ "removeBucket successful."

listObjects :: Bucket -> Maybe Text -> Bool -> C.Producer Minio ObjectInfo

List objects in the given bucket.

Parameters

In the expression listObjects bucketName prefix recursive the arguments are:

Param	Type	Description
bucketName	Bucket (alias for Text)	Name of the bucket
prefix	Maybe Text	Optional prefix that listed objects should have
recursive	Bool	True indicates recursive style listing and False indicates directory style listing delimited by '/'.

Return Value

Return type	Description
C.Producer Minio ObjectInfo	A Conduit Producer of ObjectInfo values corresponding to each incomplete multipart upload

ObjectInfo record type

Field	Type	Description
oiObject	Object (alias for Text)	Name of object
oiModTime	UTCTime	Last modified time of the object
oiETag	ETag (alias for Text)	ETag of the object
oiSize	Int64	Size of the object in bytes

Example

import Data.Conduit ($$)
import Conduit.Combinators (sinkList)

main :: IO ()
main = do
  let
    bucket = "test"

  -- Performs a recursive listing of all objects under bucket "test"
  -- on play.minio.io.
  res <- runResourceT $ runMinio minioPlayCI $ do
    listObjects bucket Nothing True $$ sinkList
  print res

listIncompleteUploads :: Bucket -> Maybe Prefix -> Bool -> C.Producer Minio UploadInfo

List incompletely uploaded objects.

Parameters

In the expression listIncompleteUploads bucketName prefix recursive the parameters are:

Param	Type	Description
bucketName	Bucket (alias for Text)	Name of the bucket
prefix	Maybe Text	Optional prefix that listed objects should have.
recursive	Bool	True indicates recursive style listing and Talse indicates directory style listing delimited by '/'.

Return Value

Return type	Description
C.Producer Minio UploadInfo	A Conduit Producer of UploadInfo values corresponding to each incomplete multipart upload

UploadInfo record type

Field	Type	Description
uiKey	Object	Name of incompletely uploaded object
uiUploadId	String	Upload ID of incompletely uploaded object
uiSize	Int64	Size of incompletely uploaded object

Example

import Data.Conduit ($$)
import Conduit.Combinators (sinkList)

main :: IO ()
main = do
  let
    bucket = "test"

  -- Performs a recursive listing of all incompletely uploaded objects
  -- under bucket "test" on play.minio.io.
  res <- runResourceT $ runMinio minioPlayCI $ do
    listIncompleteUploads bucket Nothing True $$ sinkList
  print res

3. Object operations

getObject :: Bucket -> Object -> Minio (C.ResumableSource Minio ByteString)

Get an object from the service.

Parameters

In the expression getObject bucketName objectName the parameters are:

Param	Type	Description
bucketName	Bucket (alias for Text)	Name of the bucket
objectName	Object (alias for Text)	Name of the object

Return Value

The return value can be incrementally read to process the contents of the object.

Return type	Description
C.ResumableSource Minio ByteString	A Conduit ResumableSource of ByteString values.

Example

import Data.Conduit ($$+-)
import Data.Conduit.Binary (sinkLbs)

main :: IO ()
main = do
  let
    bucket = "mybucket"
    object = "myobject"

  -- Lists the parts in an incompletely uploaded object identified by
  -- bucket, object and upload ID.
  res <- runResourceT $ runMinio minioPlayCI $ do
           source <- getObject bucket object
           src $$+- sinkLbs

  -- the following the prints the contents of the object.
  print res

putObject :: Bucket -> Object -> C.Producer Minio ByteString -> Maybe Int64 -> Minio ()

fGetObject :: Bucket -> Object -> FilePath -> Minio ()

fPutObject :: Bucket -> Object -> FilePath -> Minio ()

copyObject :: Bucket -> Object -> CopyPartSource -> Minio ()

removeObject :: Bucket -> Object -> Minio ()