lib/fog/aws/requests/storage/get_object.rb
module Fog
module AWS
class Storage
class Real
# Get an object from S3
#
# @param bucket_name [String] Name of bucket to read from
# @param object_name [String] Name of object to read
# @param options [Hash]
# @option options If-Match [String] Returns object only if its etag matches this value, otherwise returns 412 (Precondition Failed).
# @option options If-Modified-Since [Time] Returns object only if it has been modified since this time, otherwise returns 304 (Not Modified).
# @option options If-None-Match [String] Returns object only if its etag differs from this value, otherwise returns 304 (Not Modified)
# @option options If-Unmodified-Since [Time] Returns object only if it has not been modified since this time, otherwise returns 412 (Precodition Failed).
# @option options Range [String] Range of object to download
# @option options versionId [String] specify a particular version to retrieve
# @option options query[Hash] specify additional query string
#
# @return [Excon::Response] response:
# * body [String]- Contents of object
# * headers [Hash]:
# * Content-Length [String] - Size of object contents
# * Content-Type [String] - MIME type of object
# * ETag [String] - Etag of object
# * Last-Modified [String] - Last modified timestamp for object
#
# @see http://docs.amazonwebservices.com/AmazonS3/latest/API/RESTObjectGET.html
def get_object(bucket_name, object_name, options = {}, &block)
unless bucket_name
raise ArgumentError.new('bucket_name is required')
end
unless object_name
raise ArgumentError.new('object_name is required')
end
params = { :headers => {} }
params[:query] = options.delete('query') || {}
if version_id = options.delete('versionId')
params[:query] = params[:query].merge({'versionId' => version_id})
end
params[:headers].merge!(options)
if options['If-Modified-Since']
params[:headers]['If-Modified-Since'] = Fog::Time.at(options['If-Modified-Since'].to_i).to_date_header
end
if options['If-Unmodified-Since']
params[:headers]['If-Unmodified-Since'] = Fog::Time.at(options['If-Unmodified-Since'].to_i).to_date_header
end
idempotent = true
if block_given?
params[:response_block] = Proc.new(&block)
idempotent = false
end
request(params.merge!({
:expects => [ 200, 206 ],
:bucket_name => bucket_name,
:object_name => object_name,
:idempotent => idempotent,
:method => 'GET',
}))
end
end
class Mock # :nodoc:all
def get_object(bucket_name, object_name, options = {}, &block)
version_id = options.delete('versionId')
unless bucket_name
raise ArgumentError.new('bucket_name is required')
end
unless object_name
raise ArgumentError.new('object_name is required')
end
response = Excon::Response.new
if (bucket = self.data[:buckets][bucket_name])
object = nil
if bucket[:objects].key?(object_name)
object = version_id ? bucket[:objects][object_name].find { |object| object['VersionId'] == version_id} : bucket[:objects][object_name].first
end
if (object && !object[:delete_marker])
if options['If-Match'] && options['If-Match'] != object['ETag']
response.status = 412
raise(Excon::Errors.status_error({:expects => 200}, response))
elsif options['If-Modified-Since'] && options['If-Modified-Since'] >= Time.parse(object['Last-Modified'])
response.status = 304
raise(Excon::Errors.status_error({:expects => 200}, response))
elsif options['If-None-Match'] && options['If-None-Match'] == object['ETag']
response.status = 304
raise(Excon::Errors.status_error({:expects => 200}, response))
elsif options['If-Unmodified-Since'] && options['If-Unmodified-Since'] < Time.parse(object['Last-Modified'])
response.status = 412
raise(Excon::Errors.status_error({:expects => 200}, response))
else
response.status = 200
for key, value in object
case key
when 'Cache-Control', 'Content-Disposition', 'Content-Encoding', 'Content-Length', 'Content-MD5', 'Content-Type', 'ETag', 'Expires', 'Last-Modified', /^x-amz-meta-/
response.headers[key] = value
end
end
response.headers['x-amz-version-id'] = object['VersionId'] if bucket[:versioning]
body = object[:body]
if options['Range']
# since AWS S3 itself does not support multiple range headers, we will use only the first
ranges = byte_ranges(options['Range'], body.size)
unless ranges.nil? || ranges.empty?
response.status = 206
body = body[ranges.first]
end
end
unless block_given?
response.body = body
else
data = StringIO.new(body)
remaining = total_bytes = data.length
while remaining > 0
chunk = data.read([remaining, Excon::CHUNK_SIZE].min)
block.call(chunk, remaining, total_bytes)
remaining -= Excon::CHUNK_SIZE
end
end
end
elsif version_id && !object
response.status = 400
response.body = {
'Error' => {
'Code' => 'InvalidArgument',
'Message' => 'Invalid version id specified',
'ArgumentValue' => version_id,
'ArgumentName' => 'versionId',
'RequestId' => Fog::Mock.random_hex(16),
'HostId' => Fog::Mock.random_base64(65)
}
}
raise(Excon::Errors.status_error({:expects => 200}, response))
else
response.status = 404
response.body = "...<Code>NoSuchKey<\/Code>..."
raise(Excon::Errors.status_error({:expects => 200}, response))
end
else
response.status = 404
response.body = "...<Code>NoSuchBucket</Code>..."
raise(Excon::Errors.status_error({:expects => 200}, response))
end
response
end
private
# === Borrowed from rack
# Parses the "Range:" header, if present, into an array of Range objects.
# Returns nil if the header is missing or syntactically invalid.
# Returns an empty array if none of the ranges are satisfiable.
def byte_ranges(http_range, size)
# See <http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35>
return nil unless http_range
ranges = []
http_range.split(/,\s*/).each do |range_spec|
matches = range_spec.match(/bytes=(\d*)-(\d*)/)
return nil unless matches
r0,r1 = matches[1], matches[2]
if r0.empty?
return nil if r1.empty?
# suffix-byte-range-spec, represents trailing suffix of file
r0 = [size - r1.to_i, 0].max
r1 = size - 1
else
r0 = r0.to_i
if r1.empty?
r1 = size - 1
else
r1 = r1.to_i
return nil if r1 < r0 # backwards range is syntactically invalid
r1 = size-1 if r1 >= size
end
end
ranges << (r0..r1) if r0 <= r1
end
ranges
end
end
end
end
end