couchbeam应用

1、couchbeam是基于erlang的couchdb客户端.couchbeam是一个otp应用程序,所以在使用前必需先启动couchbeam

couchbeam:start().

2、创建数据库的连接

%% 如需要权限,請看下方Option的basic_auth
Host = "localhost",
Port = 5984,
Prefix = "",
Options = [],
S = couchbeam:server_connection(Host, Port, Prefix, Options).
%% @spec server_connection(Host::string(), Port::integer(),
%%                        Prefix::string(), Options::optionList()) 
%%                        -> Server::server()
%% optionList() = [option()]
%% option() =
%%          {is_ssl, boolean()}                |
%%          {ssl_options, [SSLOpt]}            |
%%          {pool_name, atom()}                |
%%          {proxy_host, string()}             |
%%          {proxy_port, integer()}            |
%%          {proxy_user, string()}             |
%%          {proxy_password, string()}         |
%%          {basic_auth, {username(), password()}} |
%%          {cookie, string()}                 |
%%          {oauth, oauthOptions()}
%%
%% username() = string()
%% password() = string()
%% SSLOpt = term()
%% oauthOptions() = [oauth()]
%% oauth() = 
%%          {consumer_key, string()} |
%%          {token, string()} |
%%          {token_secret, string()} |
%%          {consumer_secret, string()} |
%%          {signature_method, string()}
%%

3、打开或创建一个数据库

ptions = [],
{ok, Db} = couchbeam:open_db(Server, "testdb", Options).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Options = [],
{ok, Db} = couchbeam:create_db(Server, "testdb", Options).

4. 创建一个文档

Doc = {[
{<<"_id">>, <<"test">>},
{<<"content">>, <<"some text">>}
]}.
{ok, Doc1} = couchbeam:save_doc(Db, Doc).

5. 检索文件

{ok, Doc2} = couchbeam:open_doc(Db, "test").
%%If you want a specific revision:
Rev = couchbeam_doc:get_rev(Doc1),
Options = [{rev, Rev}],
{ok, Doc3} = couchbeam:open_doc(Db, "test", Options).

6. 取得所有文档

Options = [{include_docs, "true"}],
{ok, AllDocs} = couchbeam:all_docs(Db, Options).

或者:

{ok, Results} = couchbeam_view:fetch(AllDocs).

7. Couchdb views - Map/Reduce

Options = [],
DesignNam = "designname",
ViewName = "viewname",
{ok, View} = couchbeam:view(Db, {DesignNam, ViewName}, Options).

8. Put,Fetch and Delete documents attachments

%% 上传一个附件
DocID = "test",
AttName = "test.txt",
Att = "some content I want to attach",
Options = []
{ok, _Result} = couchbeam:put_attachment(Db, DocId, AttName, Att, Options).
%% 取出一个附件
{ok Att1} = couchbeam:fetch_attachment(Db, DocId, AttName).
%% 删除一个附件
{ok, Doc4} = couchbeam:open_doc(Db, DocID),
ok = couchbeam:delete_attachment(Db, Doc4, AttName).

9. Changes

Options = [],
{ok, Changes} = couchbeam:changes_wait_once(Db, Options).

10、如想修改数据库的admins/readers,在couchbeam没找到现成方法,望知道的留言相告.简单实现了下

%%  add auth to database	
	_json = "{\"admins\":{\"names\":[\"user1\"],\"roles\":[]},\"readers\":{\"names\":[\"user2\"],\"roles\":[]}}",
	Result = couchbeam:db_request(put, "http://127.0.0.1:5984/d2/_security",[], Options,[],erlang:list_to_binary(_json)),

couchdb权限介紹