AWS - Julia interface to Amazon Web Services

This package is a WIP for providing a native Julia interface to the Amazon Web Services API

Initially, the EC2 and S3 API will be supported.

Current status

• Most of the APIs are yet untested. Any testing will be helpful. The REST API does not not match exactly in certain cases with the WSDL. For the EC2 API, the bulk of the code is generated from the WSDL while it has been translated by hand for the S3 API. In certain cases breakage may occur due to wrong request syntax.

  Please file issues on GitHub with the output from running the request in debug mode, i.e., with env.dbg = true.

Usage

• Each of the functions takes in an AWSEnv as the first parameter

type AWSEnv
    aws_id::ASCIIString         # AWS Access Key id
    aws_seckey::ASCIIString     # AWS Secret key for signing requests
    aws_token::ASCIIString      # AWS Security Token for temporary credentials
    region::AbstractString      # region name
    ep_host::AbstractString     # region endpoint (host)
    ep_path::AbstractString     # region endpoint (path)
    sig_ver::Int                # AWS signature version (2 or 4)
    timeout::Float64            # request timeout in seconds, if set to 0.0, request will never time out. Default is 0.0
    dry_run::Bool               # If true, no actual request will be made - implies dbg flag below
    dbg::Bool                   # print request and raw response to screen

end

Constructors:

AWSEnv(; id=AWS_ID, key=AWS_SECKEY, token=AWS_TOKEN, ec2_creds=false, region=US_EAST_1, ep="", sig_ver=4, timeout=0.0, dr=false, dbg=false)

• The AWS_ID and AWS_SECKEY are initialized from env if available. Else a file ~/.awssecret is read (if available) for the same.
• The AWS_TOKEN is an empty string by default. Override token if the id and key are temporary security credentials.
• Set ec2_creds to true to automatically retrieve temporary security credentials if running on an EC2 instance that has such credentials.
• Set region to one of the AWS region name strings, e.g., "us-east-1". Not needed if setting ep.
• ep can contain both a hostname and a pathname for an AWS endpoint. It is generally not needed when using native AWS services; use region instead. If using a service that emulates AWS, set ep to the hostname of the endpoint to be used. If both region and ep are set, the host portion of ep will override region, and the path portion of ep will be used in conjunction with region.
• sig_ver must be set to 2 or 4. Some AWS services require one signature version or the other, in which case this value will be ignored.

S3 API

• This package uses the REST interface of S3

• The type names, function names, etc follow the names specified in http://docs.aws.amazon.com/AmazonS3/latest/API/APIRest.html as well as in http://s3.amazonaws.com/doc/2006-03-01/AmazonS3.wsdl

• Sample code

using AWS
using AWS.S3

env = AWSEnv(timeout=60.0)

bkt = "some_globally_unique_name"

println("List all buckets")
resp=S3.list_all_buckets(env)
println(resp.obj)

println("Create a bucket")
acl=S3.S3_ACL()
acl.acl="private"
resp=S3.create_bkt(env, bkt, acl=acl)
println("$(resp.http_code), $(resp.obj)")

println("Add a file")
resp = S3.put_object(env, bkt, "file1", "Hello ")
println("$(resp.http_code), $(resp.obj)")


println("Add another file")
resp = S3.put_object(env, bkt, "file2", "World ")
println("$(resp.http_code), $(resp.obj)")


println("List bucket")
resp = S3.get_bkt(env, bkt)
println("$(resp.http_code), $(resp.obj)")

println("Get file 1")
resp = S3.get_object(env, bkt, "file1")
println("$(resp.http_code), $(resp.obj)")

println("Get file 2")
resp = S3.get_object(env, bkt, "file2")
println("$(resp.http_code), $(resp.obj)")


println("Delete file 1")
resp = S3.del_object(env, bkt, "file1")
println("$(resp.http_code), $(resp.obj)")

println("Delete file 2 using the multi api")
resp = S3.del_object_multi(env, bkt, S3.DeleteObjectsType([S3.ObjectType("file2")]))
println("$(resp.http_code), $(resp.obj)")


println("Delete Bucket")
resp = S3.del_bkt(env, bkt)
println("$(resp.http_code), $(resp.obj)")

• Each of the S3 APIs returns an object of type

type S3Response
    content_length::Int  
    date::String            # The date and time Amazon S3 responded, for example, Wed, 01 Mar 2009 12:00:00 GMT.
    server::String          # The name of the server that created the response.
    eTag::String
    http_code::Int

    # Common amz fields
    delete_marker::Bool
    id_2::String
    request_id::String
    version_id::String

    headers::Dict           # All header fields

    obj::Any                # If the response was an XML representing a Julia S3 response type,
                            # it is parsed and set here.
                            # Else it will contain an IOBuffer object

    pd::Union(ETree, Nothing)
end

EC2 API

EC2 has two sets of APIs

• One is a lower level API that directly maps onto Amazon's WSDL for the service.

• The other is a simple API that provides limited functionality but with a a higher abstraction.

EC2 Simple API

• Currently the following are available:

• ec2_terminate

• ec2_launch

• ec2_start

• ec2_stop

• ec2_show_status

• ec2_get_hostnames

• ec2_instances_by_tag

• ec2_addprocs

These are described here The source is in src/ec2_simple.jl

A generic API is ec2_basic

ec2_basic(env::AWSEnv, action::String, params_in::Dict{Any, Any}) just bundles the supplied params_in into an EC2 request. It is meant to be used while bugs, if any, in the advanced (generated) code exist for any of the APIs. Values in the params can be basic julia types, CalendarTime, Dict or an Array itself. Keys in the Dict MUST be same as those mentioned in the Amazon EC2 documentation for the corresponding action.

EC2 Advanced API

Much of the boilerplate code is generated from the corresponding WSDL. For example, for the advanced API, the Julia types and functions are based on http://s3.amazonaws.com/ec2-downloads/ec2.wsdl

Exported functions are in ec2_operations.jl

Types are defined in ec2_types.jl

Names and usage are similar to the AWS documentation http://awsdocs.s3.amazonaws.com/EC2/latest/ec2-api.pdf

Each of the EC2 "actions" have a corresponding Julia function which takes in the appropriate Julia type.

For example : RunInstances(env::AWSEnv , msg::RunInstancesType) (defined in ec2_operations.jl) where

RunInstancesType (defined in ec2_types.jl) is

type RunInstancesType
    imageId::Union(ASCIIString, Nothing)
    minCount::Union(Int32, Nothing)
    maxCount::Union(Int32, Nothing)
    ...

    RunInstancesType(; imageId=nothing, minCount=nothing, maxCount=nothing, keyName=nothing, groupSet=nothing, additionalInfo=nothing, userData=nothing, addressingType=nothing, instanceType=nothing, placement=nothing, kernelId=nothing, ramdiskId=nothing, blockDeviceMapping=nothing, monitoring=nothing, subnetId=nothing, disableApiTermination=nothing, instanceInitiatedShutdownBehavior=nothing, license=nothing, privateIpAddress=nothing, clientToken=nothing, networkInterfaceSet=nothing, iamInstanceProfile=nothing, ebsOptimized=nothing) =
         new(imageId, minCount, maxCount, keyName, groupSet, additionalInfo, userData, addressingType, instanceType, placement, kernelId, ramdiskId, blockDeviceMapping, monitoring, subnetId, disableApiTermination, instanceInitiatedShutdownBehavior, license, privateIpAddress, clientToken, networkInterfaceSet, iamInstanceProfile, ebsOptimized)
end

Alternatively, the request can also be executed with the request type replaced by keyword arguments.

For example For example : RunInstances(env, imageId="ami-xxxxxxxx", minCount=1)```

Each of the functions returns an object of type:

type EC2Response
    http_code::Int
    headers
    body::Union(String, Nothing)
    pd::Union(ETree, Nothing)
    obj::Any
end

In the event of an error, EC2Response.obj has an object of type

type EC2Error
    code::String
    msg::String
    request_id::Union(String, Nothing)
end

For succcessful requests, EC2Response.obj will contain an object of the appropriate type.

For example, for RunInstances, the EC2Response.obj will be of type RunInstancesResponseType

Julia Dependencies

Calendar

LibExpat

libCURL

Binary dependencies

libcurl must be installed

libexpat must be installed

NOTE

• The crypto functions required for this package are in https://github.com/amitmurthy/AWS.jl/blob/master/src/crypto.jl, since OpenSSL.jl does not yet support the functions this package needs. This will be replaced with calls to OpenSSL.jl when it supports the same.