| Copyright | (c) 2013-2016 Brendan Hay |
|---|---|
| License | Mozilla Public License, v. 2.0. |
| Maintainer | Brendan Hay <brendan.g.hay@gmail.com> |
| Stability | provisional |
| Portability | non-portable (GHC extensions) |
| Safe Haskell | None |
| Language | Haskell2010 |
Control.Monad.Trans.AWS
Contents
Description
The AWST transformer provides the environment required to perform AWS
operations. The transformer is intended to be used directly
or embedded as a layer within a transformer stack.
Network.AWS contains an IO specialised version of AWST with a typeclass
to assist in automatically lifting operations.
- type AWST = AWST' Env
- data AWST' r m a
- runAWST :: HasEnv r => r -> AWST' r m a -> m a
- runResourceT :: MonadBaseControl IO m => ResourceT m a -> m a
- type AWSConstraint r m = (MonadCatch m, MonadResource m, MonadReader r m, HasEnv r)
- newEnv :: (Applicative m, MonadIO m, MonadCatch m) => Credentials -> m Env
- data Env
- class HasEnv a where
- data Credentials
- data Region :: *
- = NorthVirginia
- | Ohio
- | NorthCalifornia
- | Oregon
- | Tokyo
- | Seoul
- | Mumbai
- | Singapore
- | Sydney
- | SaoPaulo
- | Ireland
- | Frankfurt
- | GovCloud
- | GovCloudFIPS
- | Beijing
- send :: (AWSConstraint r m, AWSRequest a) => a -> m (Rs a)
- paginate :: (AWSConstraint r m, AWSPager a) => a -> Source m (Rs a)
- await :: (AWSConstraint r m, AWSRequest a) => Wait a -> a -> m Accept
- configure :: HasEnv a => Service -> a -> a
- override :: HasEnv a => (Service -> Service) -> a -> a
- reconfigure :: (MonadReader r m, HasEnv r) => Service -> m a -> m a
- within :: (MonadReader r m, HasEnv r) => Region -> m a -> m a
- once :: (MonadReader r m, HasEnv r) => m a -> m a
- timeout :: (MonadReader r m, HasEnv r) => Seconds -> m a -> m a
- class ToHashedBody a where
- toHashed :: a -> HashedBody
- hashedFile :: MonadIO m => FilePath -> m HashedBody
- hashedBody :: Digest SHA256 -> Integer -> Source (ResourceT IO) ByteString -> HashedBody
- class ToBody a where
- newtype ChunkSize :: * = ChunkSize Int
- defaultChunkSize :: ChunkSize
- chunkedFile :: MonadIO m => ChunkSize -> FilePath -> m RqBody
- unsafeChunkedBody :: ChunkSize -> Integer -> Source (ResourceT IO) ByteString -> RqBody
- sinkBody :: MonadResource m => RsBody -> Sink ByteString m a -> m a
- getFileSize :: MonadIO m => FilePath -> m Integer
- sinkMD5 :: Monad m => Consumer ByteString m (Digest MD5)
- sinkSHA256 :: Monad m => Consumer ByteString m (Digest SHA256)
- presignURL :: (MonadIO m, MonadReader r m, HasEnv r, AWSRequest a) => UTCTime -> Seconds -> a -> m ByteString
- presign :: (MonadIO m, MonadReader r m, HasEnv r, AWSRequest a) => UTCTime -> Seconds -> a -> m ClientRequest
- isEC2 :: (MonadIO m, MonadReader r m, HasEnv r) => m Bool
- dynamic :: (MonadIO m, MonadThrow m, MonadReader r m, HasEnv r) => Dynamic -> m ByteString
- metadata :: (MonadIO m, MonadThrow m, MonadReader r m, HasEnv r) => Metadata -> m ByteString
- userdata :: (MonadIO m, MonadCatch m, MonadReader r m, HasEnv r) => m (Maybe ByteString)
- data Dynamic
- data Metadata
- = AMIId
- | AMILaunchIndex
- | AMIManifestPath
- | AncestorAMIIds
- | BlockDevice !Mapping
- | Hostname
- | IAM !Info
- | InstanceAction
- | InstanceId
- | InstanceType
- | KernelId
- | LocalHostname
- | LocalIPV4
- | MAC
- | Network !Text !Interface
- | AvailabilityZone
- | ProductCodes
- | PublicHostname
- | PublicIPV4
- | OpenSSHKey
- | RAMDiskId
- | ReservationId
- | SecurityGroups
- class AsError a where
- class AsAuthError a where
- trying :: MonadCatch m => Getting (First a) SomeException a -> m r -> m (Either a r)
- catching :: MonadCatch m => Getting (First a) SomeException a -> m r -> (a -> m r) -> m r
- type Logger = LogLevel -> Builder -> IO ()
- data LogLevel :: *
- newLogger :: MonadIO m => LogLevel -> Handle -> m Logger
- data Endpoint :: * = Endpoint {}
- setEndpoint :: Bool -> ByteString -> Int -> Service -> Service
- module Network.AWS.Types
- module Network.AWS.Waiter
- module Network.AWS.Pager
- data RqBody :: *
- data HashedBody :: *
- data ChunkedBody :: *
- data RsBody :: *
Running AWS Actions
Instances
runAWST :: HasEnv r => r -> AWST' r m a -> m a Source #
Run an AWST action with the specified environment.
runResourceT :: MonadBaseControl IO m => ResourceT m a -> m a #
Unwrap a ResourceT transformer, and call all registered release actions.
Note that there is some reference counting involved due to resourceForkIO.
If multiple threads are sharing the same collection of resources, only the
last call to runResourceT will deallocate the resources.
Since 0.3.0
type AWSConstraint r m = (MonadCatch m, MonadResource m, MonadReader r m, HasEnv r) Source #
An alias for the constraints required to send requests,
which AWST implicitly fulfils.
Authentication and Environment
Arguments
| :: (Applicative m, MonadIO m, MonadCatch m) | |
| => Credentials | Credential discovery mechanism. |
| -> m Env |
Creates a new environment with a new Manager without debug logging
and uses getAuth to expand/discover the supplied Credentials.
Lenses from HasEnv can be used to further configure the resulting Env.
Since: 1.5.0 - The region is now retrieved from the AWS_REGION environment
variable (identical to official SDKs), or defaults to us-east-1.
You can override the Env region by using envRegion, or the current operation's
region by using within.
Since: 1.3.6 - The default logic for retrying HttpExceptions now uses
retryConnectionFailure to retry specific connection failure conditions up to 3 times.
Previously only service specific errors were automatically retried.
This can be reverted to the old behaviour by resetting the Env using
envRetryCheck lens to (\_ _ -> False).
Throws AuthError when environment variables or IAM profiles cannot be read.
See: newEnvWith.
The environment containing the parameters required to make AWS requests.
Minimal complete definition
Methods
environment :: Lens' a Env Source #
envRegion :: Lens' a Region Source #
The current region.
envLogger :: Lens' a Logger Source #
The function used to output log messages.
envRetryCheck :: Lens' a (Int -> HttpException -> Bool) Source #
The function used to determine if an HttpException should be retried.
envOverride :: Lens' a (Dual (Endo Service)) Source #
The currently applied overrides to all Service configuration.
envManager :: Lens' a Manager Source #
The Manager used to create and manage open HTTP connections.
envAuth :: Lens' a Auth Source #
The credentials used to sign requests for authentication with AWS.
envEC2 :: Getter a (IORef (Maybe Bool)) Source #
A memoised predicate for whether the underlying host is an EC2 instance.
Credential Discovery
data Credentials Source #
Determines how AuthN/AuthZ information is retrieved.
Constructors
| FromKeys AccessKey SecretKey | Explicit access and secret keys. See |
| FromSession AccessKey SecretKey SessionToken | Explicit access key, secret key and a session token. See |
| FromEnv Text Text (Maybe Text) (Maybe Text) | Lookup specific environment variables for access key, secret key, an optional session token, and an optional region, respectively. |
| FromProfile Text | An IAM Profile name to lookup from the local EC2 instance-data. Environment variables to lookup for the access key, secret key and optional session token. |
| FromFile Text FilePath | A credentials profile name (the INI section) and the path to the AWS credentials file. |
| Discover | Attempt credentials discovery via the following steps:
An attempt is made to resolve http://instance-data rather than directly retrieving http://169.254.169.254 for IAM profile information. This assists in ensuring the DNS lookup terminates promptly if not running on EC2. |
Instances
AuthN/AuthZ information is handled similarly to other AWS SDKs. You can read some of the options available here.
When running on an EC2 instance and using FromProfile or Discover, a thread
is forked which transparently handles the expiry and subsequent refresh of IAM
profile information. See fromProfileName for more information.
Supported Regions
The available AWS regions.
Constructors
| NorthVirginia | US East ('us-east-1'). |
| Ohio | US East ('us-east-2'). |
| NorthCalifornia | US West ('us-west-1'). |
| Oregon | US West ('us-west-2'). |
| Tokyo | Asia Pacific ('ap-northeast-1'). |
| Seoul | Asia Pacific ('ap-northeast-2'). |
| Mumbai | Asia Pacific ('ap-south-1'). |
| Singapore | Asia Pacific ('ap-southeast-1'). |
| Sydney | Asia Pacific ('ap-southeast-2'). |
| SaoPaulo | South America ('sa-east-1'). |
| Ireland | EU ('eu-west-1'). |
| Frankfurt | EU ('eu-central-1'). |
| GovCloud | US GovCloud ('us-gov-west-1'). |
| GovCloudFIPS | US GovCloud FIPS (S3 Only, 'fips-us-gov-west-1'). |
| Beijing | China ('cn-north-1'). |
Sending Requests
To send a request you need to create a value of the desired operation type using
the relevant constructor, as well as any further modifications of default/optional
parameters using the appropriate lenses. This value can then be sent using send
or paginate and the library will take care of serialisation/authentication and
so forth.
The default Service configuration for a request contains retry configuration that is used to
determine if a request can safely be retried and what kind of back off/on strategy
should be used. (Usually exponential.)
Typically services define retry strategies that handle throttling, general server
errors and transport errors. Streaming requests are never retried.
send :: (AWSConstraint r m, AWSRequest a) => a -> m (Rs a) Source #
Send a request, returning the associated response if successful.
Throws Error.
Pagination
Some AWS operations return results that are incomplete and require subsequent
requests in order to obtain the entire result set. The process of sending
subsequent requests to continue where a previous request left off is called
pagination. For example, the ListObjects operation of Amazon S3 returns up to
1000 objects at a time, and you must send subsequent requests with the
appropriate Marker in order to retrieve the next page of results.
Operations that have an AWSPager instance can transparently perform subsequent
requests, correctly setting Markers and other request facets to iterate through
the entire result set of a truncated API operation. Operations which support
this have an additional note in the documentation.
Many operations have the ability to filter results on the server side. See the individual operation parameters for details.
paginate :: (AWSConstraint r m, AWSPager a) => a -> Source m (Rs a) Source #
Repeatedly send a request, automatically setting markers and paginating over multiple responses while available.
Throws Error.
Waiters
Waiters poll by repeatedly sending a request until some remote success condition
configured by the Wait specification is fulfilled. The Wait specification
determines how many attempts should be made, in addition to delay and retry strategies.
Error conditions that are not handled by the Wait configuration will be thrown,
or the first successful response that fulfills the success condition will be
returned.
Wait specifications can be found under the Network.AWS.{ServiceName}.Waiters
namespace for services which support await.
await :: (AWSConstraint r m, AWSRequest a) => Wait a -> a -> m Accept Source #
Service Configuration
When a request is sent, various values such as the endpoint,
retry strategy, timeout and error handlers are taken from the associated Service
for a request. For example, DynamoDB will use the dynamoDB
configuration when sending PutItem, Query and all other operations.
You can modify a specific Service's default configuration by using
configure or reconfigure. To modify all configurations simultaneously, see override.
An example of how you might alter default configuration using these mechanisms
is demonstrated below. Firstly, the default dynamoDB service is configured to
use non-SSL localhost as the endpoint:
let dynamo :: Service
dynamo = setEndpoint False "localhost" 8000 dynamoDBThe updated configuration is then passed to the Env during setup:
e <- newEnv Discover <&> configure dynamo
runResourceT . runAWS e $ do
-- This S3 operation will communicate with remote AWS APIs.
x <- send listBuckets
-- DynamoDB operations will communicate with localhost:8000.
y <- send listTables
-- Any operations for services other than DynamoDB, are not affected.
...You can also scope the Endpoint modifications (or any other Service configuration)
to specific actions:
e <- newEnv Discover
runResourceT . runAWS e $ do
-- Service operations here will communicate with AWS, even DynamoDB.
x <- send listTables
reconfigure dynamo $ do
-- In here, DynamoDB operations will communicate with localhost:8000,
-- with operations for services not being affected.
...Functions such as within, once, and timeout likewise modify the underlying
configuration for all service requests within their respective scope.
Overriding Defaults
configure :: HasEnv a => Service -> a -> a Source #
Configure a specific service. All requests belonging to the supplied service will use this configuration instead of the default.
It's suggested you use a modified version of the default service, such
as Network.AWS.DynamoDB.dynamoDB.
See: reconfigure.
override :: HasEnv a => (Service -> Service) -> a -> a Source #
Provide a function which will be added to the existing stack of overrides applied to all service configuration.
To override a specific service, it's suggested you use
either configure or reconfigure with a modified version of the default
service, such as Network.AWS.DynamoDB.dynamoDB.
Scoped Actions
reconfigure :: (MonadReader r m, HasEnv r) => Service -> m a -> m a Source #
Scope an action such that all requests belonging to the supplied service will use this configuration instead of the default.
It's suggested you use a modified version of the default service, such
as Network.AWS.DynamoDB.dynamoDB.
See: configure.
within :: (MonadReader r m, HasEnv r) => Region -> m a -> m a Source #
Scope an action within the specific Region.
once :: (MonadReader r m, HasEnv r) => m a -> m a Source #
Scope an action such that any retry logic for the Service is
ignored and any requests will at most be sent once.
timeout :: (MonadReader r m, HasEnv r) => Seconds -> m a -> m a Source #
Scope an action such that any HTTP response will use this timeout value.
Default timeouts are chosen by considering:
- This
timeout, if set. - The related
Servicetimeout for the sent request if set. (Usually 70s) - The
envManagertimeout if set. - The default
ClientRequesttimeout. (Approximately 30s)
Streaming
Streaming comes in two flavours. HashedBody represents a request
that requires a precomputed SHA256 hash, or a ChunkedBody type for those services
that can perform incremental signing and do not require the entire payload to
be hashed (such as S3). The type signatures for request smart constructors
advertise which respective body type is required, denoting the underlying signing
capabilities.
ToHashedBody and ToBody typeclass instances are available to construct the
streaming bodies, automatically calculating any hash or size as needed for types
such as Text, ByteString, or Aeson's Value type. To read files and other
IO primitives, functions such as hashedFile, chunkedFile, or hashedBody
should be used.
For responses that contain streaming bodies (such as GetObject), you can use
sinkBody to connect the response body to a conduit
compatible sink.
Request Bodies
class ToHashedBody a where #
Anything that can be safely converted to a HashedBody.
hashedFile :: MonadIO m => FilePath -> m HashedBody Source #
Construct a HashedBody from a FilePath, calculating the SHA256 hash
and file size.
Note: While this function will perform in constant space, it will enumerate the entirety of the file contents _twice_. Firstly to calculate the SHA256 and lastly to stream the contents to the socket during sending.
See: ToHashedBody.
hashedBody :: Digest SHA256 -> Integer -> Source (ResourceT IO) ByteString -> HashedBody Source #
Construct a HashedBody from a source, manually specifying the
SHA256 hash and file size.
See: ToHashedBody.
Chunked Request Bodies
Anything that can be converted to a streaming request Body.
Minimal complete definition
Nothing
Specifies the transmitted size of the 'Transfer-Encoding' chunks.
See: defaultChunk.
defaultChunkSize :: ChunkSize #
The default chunk size of 128 KB. The minimum chunk size accepted by AWS is 8 KB, unless the entirety of the request is below this threshold.
A chunk size of 64 KB or higher is recommended for performance reasons.
chunkedFile :: MonadIO m => ChunkSize -> FilePath -> m RqBody Source #
Something something.
Will intelligently revert to HashedBody if the file is smaller than the
specified ChunkSize.
Add note about how it selects chunk size.
See: ToBody.
unsafeChunkedBody :: ChunkSize -> Integer -> Source (ResourceT IO) ByteString -> RqBody Source #
Something something.
Marked as unsafe because it does nothing to enforce the chunk size.
Typically for conduit IO functions, it's whatever ByteString's
defaultBufferSize is, around 32 KB. If the chunk size is less than 8 KB,
the request will error. 64 KB or higher chunk size is recommended for
performance reasons.
Note that it will always create a chunked body even if the request is too small.
See: ToBody.
Response Bodies
sinkBody :: MonadResource m => RsBody -> Sink ByteString m a -> m a Source #
Connect a Sink to a response stream.
File Size and MD5/SHA256
getFileSize :: MonadIO m => FilePath -> m Integer Source #
Convenience function for obtaining the size of a file.
sinkSHA256 :: Monad m => Consumer ByteString m (Digest SHA256) Source #
Presigning Requests
Presigning requires the Service signer to be an instance of AWSPresigner.
Not all signing algorithms support this.
Arguments
| :: (MonadIO m, MonadReader r m, HasEnv r, AWSRequest a) | |
| => UTCTime | Signing time. |
| -> Seconds | Expiry time. |
| -> a | Request to presign. |
| -> m ByteString |
Presign an URL that is valid from the specified time until the number of seconds expiry has elapsed.
Arguments
| :: (MonadIO m, MonadReader r m, HasEnv r, AWSRequest a) | |
| => UTCTime | Signing time. |
| -> Seconds | Expiry time. |
| -> a | Request to presign. |
| -> m ClientRequest |
Presign an HTTP request that is valid from the specified time until the number of seconds expiry has elapsed.
EC2 Instance Metadata
Metadata can be retrieved from the underlying host assuming that you're running
the code on an EC2 instance or have a compatible instance-data endpoint available.
isEC2 :: (MonadIO m, MonadReader r m, HasEnv r) => m Bool Source #
Test whether the underlying host is running on EC2. This is memoised and any external check occurs for the first invocation only.
dynamic :: (MonadIO m, MonadThrow m, MonadReader r m, HasEnv r) => Dynamic -> m ByteString Source #
Retrieve the specified Dynamic data.
Throws HttpException.
metadata :: (MonadIO m, MonadThrow m, MonadReader r m, HasEnv r) => Metadata -> m ByteString Source #
Retrieve the specified Metadata.
Throws HttpException.
userdata :: (MonadIO m, MonadCatch m, MonadReader r m, HasEnv r) => m (Maybe ByteString) Source #
Retrieve the user data. Returns Nothing if no user data is assigned
to the instance.
Throws HttpException.
Constructors
| FWS | Value showing whether the customer has enabled detailed one-minute monitoring in CloudWatch. Valid values: enabled | disabled. |
| Document | JSON containing instance attributes, such as instance-id,
private IP address, etc.
See: |
| PKCS7 | Used to verify the document's authenticity and content against the signature. |
| Signature |
Constructors
| AMIId | The AMI ID used to launch the instance. |
| AMILaunchIndex | If you started more than one instance at the same time, this value indicates the order in which the instance was launched. The value of the first instance launched is 0. |
| AMIManifestPath | The path to the AMI's manifest file in Amazon S3. If you used an Amazon EBS-backed AMI to launch the instance, the returned result is unknown. |
| AncestorAMIIds | The AMI IDs of any instances that were rebundled to create this AMI. This value will only exist if the AMI manifest file contained an ancestor-amis key. |
| BlockDevice !Mapping | See: |
| Hostname | The private hostname of the instance. In cases where multiple network interfaces are present, this refers to the eth0 device (the device for which the device number is 0). |
| IAM !Info | See: |
| InstanceAction | Notifies the instance that it should reboot in preparation for bundling. Valid values: none | shutdown | bundle-pending. |
| InstanceId | The ID of this instance. |
| InstanceType | The type of instance. See: |
| KernelId | The ID of the kernel launched with this instance, if applicable. |
| LocalHostname | The private DNS hostname of the instance. In cases where multiple network interfaces are present, this refers to the eth0 device (the device for which the device number is 0). |
| LocalIPV4 | The private IP address of the instance. In cases where multiple network interfaces are present, this refers to the eth0 device (the device for which the device number is 0). |
| MAC | The instance's media access control (MAC) address. In cases where multiple network interfaces are present, this refers to the eth0 device (the device for which the device number is 0). |
| Network !Text !Interface | See: |
| AvailabilityZone | The Availability Zone in which the instance launched. |
| ProductCodes | Product codes associated with the instance, if any. |
| PublicHostname | The instance's public DNS. If the instance is in a VPC, this category is only returned if the enableDnsHostnames attribute is set to true. For more information, see Using DNS with Your VPC. |
| PublicIPV4 | The public IP address. If an Elastic IP address is associated with the instance, the value returned is the Elastic IP address. |
| OpenSSHKey | Public key. Only available if supplied at instance launch time. |
| RAMDiskId | The ID of the RAM disk specified at launch time, if applicable. |
| ReservationId | ID of the reservation. |
| SecurityGroups | The names of the security groups applied to the instance. |
Running Asynchronous Actions
Requests can be sent asynchronously, but due to guarantees about resource closure require the use of lifted-async.
The following example demonstrates retrieving two objects from S3 concurrently:
import Control.Concurrent.Async.Lifted import Control.Lens import Control.Monad.Trans.AWS import Network.AWS.S3 do x <- async . send $ getObject "bucket" "prefix/object-foo" y <- async . send $ getObject "bucket" "prefix/object-bar" foo <- wait x bar <- wait y ...
Handling Errors
Errors are thrown by the library using MonadThrow (unless Control.Monad.Error.AWS is used).
Sub-errors of the canonical Error type can be caught using trying or
catching and the appropriate AsError Prism:
trying_Error(send $ ListObjects "bucket-name") :: EitherErrorListObjectsResponse trying_TransportError(send $ ListObjects "bucket-name") :: EitherHttpExceptionListObjectsResponse trying_SerializeError(send $ ListObjects "bucket-name") :: EitherSerializeErrorListObjectsResponse trying_ServiceError(send $ ListObjects "bucket-name") :: EitherServiceErrorListObjectsResponse
Many of the individual amazonka-* libraries export compatible Getters for
matching service specific error codes and messages in the style above.
See the Error Matchers heading in each respective library for details.
Minimal complete definition
Instances
class AsAuthError a where Source #
Minimal complete definition
Methods
_AuthError :: Prism' a AuthError Source #
A general authentication error.
_RetrievalError :: Prism' a HttpException Source #
An error occured while communicating over HTTP with the local metadata endpoint.
_MissingEnvError :: Prism' a Text Source #
The named environment variable was not found.
_InvalidEnvError :: Prism' a Text Source #
An error occured parsing named environment variable's value.
_MissingFileError :: Prism' a FilePath Source #
The specified credentials file could not be found.
_InvalidFileError :: Prism' a Text Source #
An error occured parsing the credentials file.
_InvalidIAMError :: Prism' a Text Source #
The specified IAM profile could not be found or deserialised.
Instances
trying :: MonadCatch m => Getting (First a) SomeException a -> m r -> m (Either a r) #
A variant of try that takes a Prism (or any Fold) to select which
exceptions are caught (c.f. tryJust, catchJust). If the
Exception does not match the predicate, it is re-thrown.
trying::MonadCatchm =>Prism'SomeExceptiona -> m r -> m (Eithera r)trying::MonadCatchm =>Lens'SomeExceptiona -> m r -> m (Eithera r)trying::MonadCatchm =>Traversal'SomeExceptiona -> m r -> m (Eithera r)trying::MonadCatchm =>Iso'SomeExceptiona -> m r -> m (Eithera r)trying::MonadCatchm =>GetterSomeExceptiona -> m r -> m (Eithera r)trying::MonadCatchm =>FoldSomeExceptiona -> m r -> m (Eithera r)
catching :: MonadCatch m => Getting (First a) SomeException a -> m r -> (a -> m r) -> m r #
Catch exceptions that match a given Prism (or any Fold, really).
>>>catching _AssertionFailed (assert False (return "uncaught")) $ \ _ -> return "caught""caught"
catching::MonadCatchm =>Prism'SomeExceptiona -> m r -> (a -> m r) -> m rcatching::MonadCatchm =>Lens'SomeExceptiona -> m r -> (a -> m r) -> m rcatching::MonadCatchm =>Traversal'SomeExceptiona -> m r -> (a -> m r) -> m rcatching::MonadCatchm =>Iso'SomeExceptiona -> m r -> (a -> m r) -> m rcatching::MonadCatchm =>GetterSomeExceptiona -> m r -> (a -> m r) -> m rcatching::MonadCatchm =>FoldSomeExceptiona -> m r -> (a -> m r) -> m r
Logging
The exposed logging interface is a primitive Logger function which gets
threaded through service calls and serialisation routines. This allows the
library to output useful information and diagnostics.
The newLogger function can be used to construct a simple logger which writes
output to a Handle, but in most production code you should probably consider
using a more robust logging library such as
tiny-log or
fast-logger.
type Logger = LogLevel -> Builder -> IO () #
A function threaded through various request and serialisation routines to log informational and debug messages.
Constructing a Logger
newLogger :: MonadIO m => LogLevel -> Handle -> m Logger Source #
This is a primitive logger which can be used to log builds to a Handle.
Note: A more sophisticated logging library such as tinylog or fast-logger should be used in production code.
Endpoints
Constructors
| Endpoint | |
Fields
| |
Arguments
| :: Bool | Whether to use HTTPS (ie. SSL). |
| -> ByteString | The hostname to connect to. |
| -> Int | The port number to connect to. |
| -> Service | The service configuration to override. |
| -> Service |
A convenience function for overriding the Service Endpoint.
See: serviceEndpoint.
Re-exported Types
module Network.AWS.Types
module Network.AWS.Waiter
module Network.AWS.Pager
Invariant: only services that support _both_ standard and
chunked signing expose RqBody as a parameter.
data HashedBody :: * #
An opaque request body containing a SHA256 hash.
data ChunkedBody :: * #
An opaque request body which will be transmitted via
Transfer-Encoding: chunked.
Invariant: Only services that support chunked encoding can
accept a ChunkedBody. (Currently S3.) This is enforced by the type
signatures emitted by the generator.
Instances