couchrest_model/lib/couchrest/core/database.rb
Matt Lyon b915f7f708 - Added Database#delete_attachment, for removing them directly
- Modified Database#fetch_attachment to take a doc as its first argument +as well as+ a docid, to be consistent with the other attachment methods.
- Refactored the attachment uri generation used by #fetch_attachment, #put_attachment, and #delete_attachment to a common private method, #uri_for_attachment
2009-02-02 01:25:14 -08:00

259 lines
8.9 KiB
Ruby

require 'cgi'
require "base64"
module CouchRest
class Database
attr_reader :server, :host, :name, :root
attr_accessor :bulk_save_cache_limit
# Create a CouchRest::Database adapter for the supplied CouchRest::Server
# and database name.
#
# ==== Parameters
# server<CouchRest::Server>:: database host
# name<String>:: database name
#
def initialize server, name
@name = name
@server = server
@host = server.uri
@root = "#{host}/#{name}"
@streamer = Streamer.new(self)
@bulk_save_cache = []
@bulk_save_cache_limit = 50
end
# returns the database's uri
def to_s
@root
end
# GET the database info from CouchDB
def info
CouchRest.get @root
end
# Query the <tt>_all_docs</tt> view. Accepts all the same arguments as view.
def documents params = {}
keys = params.delete(:keys)
url = CouchRest.paramify_url "#{@root}/_all_docs", params
if keys
CouchRest.post(url, {:keys => keys})
else
CouchRest.get url
end
end
# POST a temporary view function to CouchDB for querying. This is not
# recommended, as you don't get any performance benefit from CouchDB's
# materialized views. Can be quite slow on large databases.
def slow_view funcs, params = {}
keys = params.delete(:keys)
funcs = funcs.merge({:keys => keys}) if keys
url = CouchRest.paramify_url "#{@root}/_temp_view", params
JSON.parse(RestClient.post(url, funcs.to_json, {"Content-Type" => 'application/json'}))
end
# backwards compatibility is a plus
alias :temp_view :slow_view
# Query a CouchDB view as defined by a <tt>_design</tt> document. Accepts
# paramaters as described in http://wiki.apache.org/couchdb/HttpViewApi
def view name, params = {}, &block
keys = params.delete(:keys)
url = CouchRest.paramify_url "#{@root}/_view/#{name}", params
if keys
CouchRest.post(url, {:keys => keys})
else
if block_given?
@streamer.view(name, params, &block)
else
CouchRest.get url
end
end
end
# GET a document from CouchDB, by id. Returns a Ruby Hash.
def get id
slug = escape_docid(id)
hash = CouchRest.get("#{@root}/#{slug}")
doc = if /^_design/ =~ hash["_id"]
Design.new(hash)
else
Document.new(hash)
end
doc.database = self
doc
end
# GET an attachment directly from CouchDB
def fetch_attachment doc, name
docid = doc.respond_to?(:has_key?) ? doc['_id'] : doc
RestClient.get uri_for_attachment({'_id' => docid}, name)
end
# PUT an attachment directly to CouchDB
def put_attachment doc, name, file, options = {}
uri = uri_for_attachment(doc, name)
JSON.parse(RestClient.put(uri, file, options))
end
# DELETE an attachment directly from CouchDB
def delete_attachment doc, name
uri = uri_for_attachment(doc, name)
JSON.parse(RestClient.delete(uri))
end
# Save a document to CouchDB. This will use the <tt>_id</tt> field from
# the document as the id for PUT, or request a new UUID from CouchDB, if
# no <tt>_id</tt> is present on the document. IDs are attached to
# documents on the client side because POST has the curious property of
# being automatically retried by proxies in the event of network
# segmentation and lost responses.
#
# If <tt>bulk</tt> is true (false by default) the document is cached for bulk-saving later.
# Bulk saving happens automatically when #bulk_save_cache limit is exceded, or on the next non bulk save.
def save (doc, bulk = false)
if doc['_attachments']
doc['_attachments'] = encode_attachments(doc['_attachments'])
end
if bulk
@bulk_save_cache << doc
return bulk_save if @bulk_save_cache.length >= @bulk_save_cache_limit
return {"ok" => true} # Compatibility with Document#save
elsif !bulk && @bulk_save_cache.length > 0
bulk_save
end
result = if doc['_id']
slug = escape_docid(doc['_id'])
CouchRest.put "#{@root}/#{slug}", doc
else
begin
slug = doc['_id'] = @server.next_uuid
CouchRest.put "#{@root}/#{slug}", doc
rescue #old version of couchdb
CouchRest.post @root, doc
end
end
if result['ok']
doc['_id'] = result['id']
doc['_rev'] = result['rev']
doc.database = self if doc.respond_to?(:database=)
end
result
end
# POST an array of documents to CouchDB. If any of the documents are
# missing ids, supply one from the uuid cache.
#
# If called with no arguments, bulk saves the cache of documents to be bulk saved.
def bulk_save(docs = nil, use_uuids = true)
if docs.nil?
docs = @bulk_save_cache
@bulk_save_cache = []
end
if (use_uuids)
ids, noids = docs.partition{|d|d['_id']}
uuid_count = [noids.length, @server.uuid_batch_count].max
noids.each do |doc|
nextid = @server.next_uuid(uuid_count) rescue nil
doc['_id'] = nextid if nextid
end
end
CouchRest.post "#{@root}/_bulk_docs", {:docs => docs}
end
# DELETE the document from CouchDB that has the given <tt>_id</tt> and
# <tt>_rev</tt>.
#
# If <tt>bulk</tt> is true (false by default) the deletion is recorded for bulk-saving (bulk-deletion :) later.
# Bulk saving happens automatically when #bulk_save_cache limit is exceded, or on the next non bulk save.
def delete (doc, bulk = false)
raise ArgumentError, "_id and _rev required for deleting" unless doc['_id'] && doc['_rev']
if bulk
@bulk_save_cache << { '_id' => doc['_id'], '_rev' => doc['_rev'], '_deleted' => true }
return bulk_save if @bulk_save_cache.length >= @bulk_save_cache_limit
return { "ok" => true } # Mimic the non-deferred version
end
slug = escape_docid(doc['_id'])
CouchRest.delete "#{@root}/#{slug}?rev=#{doc['_rev']}"
end
# COPY an existing document to a new id. If the destination id currently exists, a rev must be provided.
# <tt>dest</tt> can take one of two forms if overwriting: "id_to_overwrite?rev=revision" or the actual doc
# hash with a '_rev' key
def copy doc, dest
raise ArgumentError, "_id is required for copying" unless doc['_id']
slug = escape_docid(doc['_id'])
destination = if dest.respond_to?(:has_key?) && dest['_id'] && dest['_rev']
"#{dest['_id']}?rev=#{dest['_rev']}"
else
dest
end
CouchRest.copy "#{@root}/#{slug}", destination
end
# MOVE an existing document to a new id. If the destination id currently exists, a rev must be provided.
# <tt>dest</tt> can take one of two forms if overwriting: "id_to_overwrite?rev=revision" or the actual doc
# hash with a '_rev' key
def move doc, dest
raise ArgumentError, "_id and _rev are required for moving" unless doc['_id'] && doc['_rev']
slug = escape_docid(doc['_id'])
destination = if dest.respond_to?(:has_key?) && dest['_id'] && dest['_rev']
"#{dest['_id']}?rev=#{dest['_rev']}"
else
dest
end
CouchRest.move "#{@root}/#{slug}?rev=#{doc['_rev']}", destination
end
# Compact the database, removing old document revisions and optimizing space use.
def compact!
CouchRest.post "#{@root}/_compact"
end
# Replicates via "pulling" from another database to this database. Makes no attempt to deal with conflicts.
def replicate_from other_db
raise ArgumentError, "must provide a CouchReset::Database" unless other_db.kind_of?(CouchRest::Database)
CouchRest.post "#{@host}/_replicate", :source => other_db.root, :target => name
end
# Replicates via "pushing" to another database. Makes no attempt to deal with conflicts.
def replicate_to other_db
raise ArgumentError, "must provide a CouchReset::Database" unless other_db.kind_of?(CouchRest::Database)
CouchRest.post "#{@host}/_replicate", :target => other_db.root, :source => name
end
# DELETE the database itself. This is not undoable and could be rather
# catastrophic. Use with care!
def delete!
CouchRest.delete @root
end
private
def uri_for_attachment doc, name
docid = escape_docid(doc['_id'])
name = CGI.escape(name)
rev = "?rev=#{doc['_rev']}" if doc['_rev']
"#{@root}/#{docid}/#{name}#{rev}"
end
def escape_docid id
/^_design\/(.*)/ =~ id ? "_design/#{CGI.escape($1)}" : CGI.escape(id)
end
def encode_attachments attachments
attachments.each do |k,v|
next if v['stub']
v['data'] = base64(v['data'])
end
attachments
end
def base64 data
Base64.encode64(data).gsub(/\s/,'')
end
end
end