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couch_replicator_api_wrap.erl
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couch_replicator_api_wrap.erl
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% Licensed under the Apache License, Version 2.0 (the "License"); you may not
% use this file except in compliance with the License. You may obtain a copy of
% the License at
%
% http:https://www.apache.org/licenses/LICENSE-2.0
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
% License for the specific language governing permissions and limitations under
% the License.
-module(couch_replicator_api_wrap).
% This module wraps the native erlang API, and allows for performing
% operations on a remote vs. local databases via the same API.
%
% Notes:
% Many options and apis aren't yet supported here, they are added as needed.
-include_lib("couch/include/couch_db.hrl").
-include_lib("couch_mrview/include/couch_mrview.hrl").
-include("couch_replicator_api_wrap.hrl").
-export([
db_open/1,
db_open/3,
db_close/1,
get_db_info/1,
get_pending_count/2,
get_view_info/3,
update_doc/3,
update_doc/4,
update_docs/3,
update_docs/4,
ensure_full_commit/1,
get_missing_revs/2,
bulk_get/3,
open_doc/3,
open_doc_revs/6,
changes_since/5,
db_uri/1,
normalize_db/1
]).
-import(couch_replicator_httpc, [
send_req/3
]).
-import(couch_util, [
encode_doc_id/1,
get_value/2,
get_value/3
]).
-define(MAX_WAIT, 5 * 60 * 1000).
-define(MAX_URL_LEN, 7000).
-define(MIN_URL_LEN, 200).
db_uri(#httpdb{url = Url}) ->
couch_util:url_strip_password(Url).
db_open(Db) ->
db_open(Db, false, []).
db_open(#httpdb{} = Db1, Create, CreateParams) ->
{ok, Db} = couch_replicator_httpc:setup(Db1),
try
case Create of
false ->
ok;
true ->
Db2 = maybe_append_create_query_params(Db, CreateParams),
send_req(
Db2,
[{method, put}],
fun
(401, _, _) ->
throw({unauthorized, ?l2b(db_uri(Db2))});
(403, _, _) ->
throw({forbidden, ?l2b(db_uri(Db2))});
(_, _, _) ->
ok
end
)
end,
send_req(
Db,
[{method, get}],
fun
(200, _, {Props}) ->
UpdateSeq = get_value(<<"update_seq">>, Props),
InstanceStart = get_value(<<"instance_start_time">>, Props),
case {UpdateSeq, InstanceStart} of
{undefined, _} ->
throw({db_not_found, ?l2b(db_uri(Db))});
{_, undefined} ->
throw({db_not_found, ?l2b(db_uri(Db))});
_ ->
{ok, Db}
end;
(200, _, _Body) ->
throw({db_not_found, ?l2b(db_uri(Db))});
(401, _, _) ->
throw({unauthorized, ?l2b(db_uri(Db))});
(403, _, _) ->
throw({forbidden, ?l2b(db_uri(Db))});
(_, _, _) ->
throw({db_not_found, ?l2b(db_uri(Db))})
end
)
catch
throw:Error ->
db_close(Db),
throw(Error);
error:Error ->
db_close(Db),
erlang:error(Error);
exit:Error ->
db_close(Db),
erlang:exit(Error)
end.
db_close(#httpdb{httpc_pool = Pool} = HttpDb) ->
couch_replicator_auth:cleanup(HttpDb),
unlink(Pool),
ok = couch_replicator_httpc_pool:stop(Pool).
get_db_info(#httpdb{} = Db) ->
send_req(
Db,
[],
fun(200, _, {Props}) ->
{ok, Props}
end
).
get_pending_count(#httpdb{} = Db, Seq) when is_number(Seq) ->
% Source looks like Apache CouchDB and not Cloudant so we fall
% back to using update sequence differences.
send_req(Db, [], fun(200, _, {Props}) ->
case get_value(<<"update_seq">>, Props) of
UpdateSeq when is_number(UpdateSeq) ->
{ok, UpdateSeq - Seq};
_ ->
{ok, null}
end
end);
get_pending_count(#httpdb{} = Db, Seq) ->
EncodedSeq = couch_replicator_utils:seq_encode(Seq),
Options = [{path, "_changes"}, {qs, [{"since", EncodedSeq}, {"limit", "0"}]}],
send_req(Db, Options, fun(200, _, {Props}) ->
{ok, couch_util:get_value(<<"pending">>, Props, null)}
end).
get_view_info(#httpdb{} = Db, DDocId, ViewName) ->
Path = io_lib:format("~s/_view/~s/_info", [DDocId, ViewName]),
send_req(
Db,
[{path, Path}],
fun(200, _, {Props}) ->
{VInfo} = couch_util:get_value(<<"view_index">>, Props, {[]}),
{ok, VInfo}
end
).
ensure_full_commit(#httpdb{} = Db) ->
send_req(
Db,
[
{method, post},
{path, "_ensure_full_commit"},
{headers, [{"Content-Type", "application/json"}]}
],
fun
(201, _, {Props}) ->
{ok, get_value(<<"instance_start_time">>, Props)};
(_, _, {Props}) ->
{error, get_value(<<"error">>, Props)}
end
).
get_missing_revs(#httpdb{} = Db, IdRevs) ->
JsonBody = {[{Id, couch_doc:revs_to_strs(Revs)} || {Id, Revs} <- IdRevs]},
send_req(
Db,
[
{method, post},
{path, "_revs_diff"},
{body, ?JSON_ENCODE(JsonBody)},
{headers, [{"Content-Type", "application/json"}]}
],
fun
(200, _, {Props}) ->
ConvertToNativeFun = fun({Id, {Result}}) ->
MissingRevs = couch_doc:parse_revs(
get_value(<<"missing">>, Result)
),
PossibleAncestors = couch_doc:parse_revs(
get_value(<<"possible_ancestors">>, Result, [])
),
{Id, MissingRevs, PossibleAncestors}
end,
{ok, lists:map(ConvertToNativeFun, Props)};
(ErrCode, _, ErrMsg) when is_integer(ErrCode) ->
{error, {revs_diff_failed, ErrCode, ErrMsg}}
end
).
bulk_get(#httpdb{} = Db, #{} = IdRevs, Options) ->
FoldFun = fun({Id, Rev}, PAs, Acc) -> [{Id, Rev, PAs} | Acc] end,
ReqDocsList = lists:sort(maps:fold(FoldFun, [], IdRevs)),
MapFun = fun({Id, Rev, PAs}) ->
#{
<<"id">> => Id,
<<"rev">> => couch_doc:rev_to_str(Rev),
<<"atts_since">> => couch_doc:revs_to_strs(PAs)
}
end,
ReqDocsMaps = lists:map(MapFun, ReqDocsList),
% We are also sending request parameters in the doc body with the hopes
% that at some point in the future we could make that the default, instead
% of having to send query parameters with a POST request as we do today
Body = options_to_json_map(Options, #{<<"docs">> => ReqDocsMaps}),
Req = [
{method, post},
{path, "_bulk_get"},
{qs, options_to_query_args(Options, [])},
{body, ?JSON_ENCODE(Body)},
{headers, [
{"Content-Type", "application/json"},
{"Accept", "application/json"}
]}
],
try
send_req(Db, Req, fun
(200, _, {[{<<"results">>, Res}]}) when is_list(Res) ->
Zip = lists:zipwith(fun bulk_get_zip/2, ReqDocsList, Res),
{ok, maps:from_list(Zip)};
(200, _, _) ->
{error, {bulk_get_failed, invalid_results}};
(ErrCode, _, _) when is_integer(ErrCode) ->
% On older Apache CouchDB instances where _bulk_get is not
% implemented we would hit the POST db/doc form uploader
% handler. When that fails the request body is not consumed and
% we'd end up recycling a worker with an unsent body in the
% connection stream. Instead of waiting for it to blow up
% eventually and consuming an extra retry attempt, proactively
% advise httpc logic to stop this worker and not return back to
% the pool.
couch_replicator_httpc:stop_http_worker(),
{error, {bulk_get_failed, ErrCode}}
end)
catch
exit:{http_request_failed, _, _, {error, {code, ErrCode}}} ->
% We are being a bit more tolerant of _bulk_get errors as we can
% always fallback to individual fetches
{error, {bulk_get_failed, ErrCode}}
end.
bulk_get_zip({Id, Rev, _}, {[_ | _] = Props}) ->
Docs = couch_util:get_value(<<"docs">>, Props),
ResId = couch_util:get_value(<<"id">>, Props),
% "docs" is a one item list, either [{"ok": Doc}] or [{"error": Error}]
case Docs of
[{[{<<"ok">>, {[_ | _]} = Doc}]}] when ResId =:= Id ->
{{Id, Rev}, couch_doc:from_json_obj(Doc)};
[{[{<<"error">>, {[_ | _] = Err}}]}] when ResId =:= Id ->
Tag = couch_util:get_value(<<"error">>, Err),
Reason = couch_util:get_value(<<"reason">>, Err),
couch_log:debug("~p bulk_get zip error ~p:~p", [?MODULE, Tag, Reason]),
{{Id, Rev}, {error, {Tag, Reason}}};
Other ->
couch_log:debug("~p bulk_get zip other error:~p", [?MODULE, Other]),
{{Id, Rev}, {error, {unexpected_bulk_get_response, Other}}}
end.
-spec open_doc_revs(#httpdb{}, binary(), list(), list(), function(), any()) -> no_return().
open_doc_revs(#httpdb{retries = 0} = HttpDb, Id, Revs, Options, _Fun, _Acc) ->
Path = encode_doc_id(Id),
QS = options_to_query_args(HttpDb, Path, [revs, {open_revs, Revs} | Options]),
Url = couch_util:url_strip_password(
couch_replicator_httpc:full_url(HttpDb, [{path, Path}, {qs, QS}])
),
couch_log:error("Replication crashing because GET ~s failed", [Url]),
exit(kaboom);
open_doc_revs(#httpdb{} = HttpDb, Id, Revs, Options, Fun, Acc) ->
Path = encode_doc_id(Id),
QS = options_to_query_args(HttpDb, Path, [revs, {open_revs, Revs} | Options]),
{Pid, Ref} = spawn_monitor(fun() ->
Self = self(),
Callback = fun
(200, Headers, StreamDataFun) ->
remote_open_doc_revs_streamer_start(Self),
{<<"--">>, _, _} = couch_httpd:parse_multipart_request(
header_value("Content-Type", Headers),
StreamDataFun,
fun mp_parse_mixed/1
);
(414, _, _) ->
exit(request_uri_too_long)
end,
Streamer = spawn_link(fun() ->
Params = [
{path, Path},
{qs, QS},
{ibrowse_options, [{stream_to, {self(), once}}]},
{headers, [{"Accept", "multipart/mixed"}]}
],
% We're setting retries to 0 here to avoid the case where the
% Streamer retries the request and ends up jumbling together two
% different response bodies. Retries are handled explicitly by
% open_doc_revs itself.
send_req(HttpDb#httpdb{retries = 0}, Params, Callback)
end),
% If this process dies normally we can leave
% the Streamer process hanging around keeping an
% HTTP connection open. This is a bit of a
% hammer approach to making sure it releases
% that connection back to the pool.
spawn(fun() ->
Ref = erlang:monitor(process, Self),
receive
{'DOWN', Ref, process, Self, normal} ->
exit(Streamer, {streamer_parent_died, Self});
{'DOWN', Ref, process, Self, _} ->
ok
end
end),
receive
{started_open_doc_revs, Ref} ->
Ret = receive_docs_loop(Streamer, Fun, Id, Revs, Ref, Acc),
exit({exit_ok, Ret})
end
end),
receive
{'DOWN', Ref, process, Pid, {exit_ok, Ret}} ->
Ret;
{'DOWN', Ref, process, Pid, {{nocatch, missing_doc}, _}} ->
throw(missing_doc);
{'DOWN', Ref, process, Pid, {{nocatch, {missing_stub, _} = Stub}, _}} ->
throw(Stub);
{'DOWN', Ref, process, Pid, {http_request_failed, _, _, max_backoff}} ->
exit(max_backoff);
{'DOWN', Ref, process, Pid, request_uri_too_long} ->
NewMaxLen = get_value(max_url_len, Options, ?MAX_URL_LEN) div 2,
case NewMaxLen < ?MIN_URL_LEN of
true ->
throw(request_uri_too_long);
false ->
couch_log:info(
"Reducing url length to ~B because of"
" 414 response",
[NewMaxLen]
),
Options1 = lists:keystore(
max_url_len,
1,
Options,
{max_url_len, NewMaxLen}
),
open_doc_revs(HttpDb, Id, Revs, Options1, Fun, Acc)
end;
{'DOWN', Ref, process, Pid, Else} ->
Url = couch_util:url_strip_password(
couch_replicator_httpc:full_url(HttpDb, [{path, Path}, {qs, QS}])
),
#httpdb{retries = Retries, wait = Wait0} = HttpDb,
Wait = 2 * erlang:min(Wait0 * 2, ?MAX_WAIT),
couch_log:notice(
"Retrying GET to ~s in ~p seconds due to error ~w",
[Url, Wait / 1000, error_reason(Else)]
),
ok = timer:sleep(Wait),
RetryDb = HttpDb#httpdb{
retries = Retries - 1,
wait = Wait
},
open_doc_revs(RetryDb, Id, Revs, Options, Fun, Acc)
end.
error_reason({http_request_failed, "GET", _Url, {error, timeout}}) ->
timeout;
error_reason({http_request_failed, "GET", _Url, {error, {_, req_timedout}}}) ->
req_timedout;
error_reason({http_request_failed, "GET", _Url, Error}) ->
Error;
error_reason(Else) ->
Else.
open_doc(#httpdb{} = Db, Id, Options) ->
send_req(
Db,
[{path, encode_doc_id(Id)}, {qs, options_to_query_args(Options, [])}],
fun
(200, _, Body) ->
{ok, couch_doc:from_json_obj(Body)};
(_, _, {Props}) ->
{error, get_value(<<"error">>, Props)}
end
).
update_doc(Db, Doc, Options) ->
update_doc(Db, Doc, Options, ?INTERACTIVE_EDIT).
update_doc(#httpdb{} = HttpDb, #doc{id = DocId} = Doc, Options, Type) ->
QArgs =
case Type of
?REPLICATED_CHANGES ->
[{"new_edits", "false"}];
_ ->
[]
end ++ options_to_query_args(Options, []),
Boundary = couch_uuids:random(),
JsonBytes = ?JSON_ENCODE(
couch_doc:to_json_obj(
Doc, [revs, attachments, follows, att_encoding_info | Options]
)
),
{ContentType, Len} = couch_doc:len_doc_to_multi_part_stream(
Boundary,
JsonBytes,
Doc#doc.atts,
true
),
Headers =
case lists:member(delay_commit, Options) of
true ->
[{"X-Couch-Full-Commit", "false"}];
false ->
[]
end ++ [{"Content-Type", ?b2l(ContentType)}, {"Content-Length", Len}],
Body = {fun stream_doc/1, {JsonBytes, Doc#doc.atts, Boundary, Len}},
send_req(
% A crash here bubbles all the way back up to run_user_fun inside
% open_doc_revs, which will retry the whole thing. That's the
% appropriate course of action, since we've already started streaming
% the response body from the GET request.
HttpDb#httpdb{retries = 0},
[
{method, put},
{path, encode_doc_id(DocId)},
{qs, QArgs},
{headers, Headers},
{body, Body}
],
fun
(Code, _, {Props}) when Code =:= 200 orelse Code =:= 201 orelse Code =:= 202 ->
{ok, couch_doc:parse_rev(get_value(<<"rev">>, Props))};
(409, _, _) ->
throw(conflict);
(Code, _, {Props}) ->
case {Code, get_value(<<"error">>, Props)} of
{401, <<"unauthorized">>} ->
throw({unauthorized, get_value(<<"reason">>, Props)});
{403, <<"forbidden">>} ->
throw({forbidden, get_value(<<"reason">>, Props)});
{412, <<"missing_stub">>} ->
throw({missing_stub, get_value(<<"reason">>, Props)});
{413, _} ->
{error, request_body_too_large};
{_, Error} ->
{error, Error}
end
end
).
update_docs(Db, DocList, Options) ->
update_docs(Db, DocList, Options, ?INTERACTIVE_EDIT).
update_docs(_Db, [], _Options, _UpdateType) ->
{ok, []};
update_docs(#httpdb{} = HttpDb, DocList, Options, UpdateType) ->
FullCommit = atom_to_list(not lists:member(delay_commit, Options)),
Prefix =
case UpdateType of
?REPLICATED_CHANGES ->
<<"{\"new_edits\":false,\"docs\":[">>;
?INTERACTIVE_EDIT ->
<<"{\"docs\":[">>
end,
Suffix = <<"]}">>,
% Note: nginx and other servers don't like PUT/POST requests without
% a Content-Length header, so we can't do a chunked transfer encoding
% and JSON encode each doc only before sending it through the socket.
{Docs, Len} = lists:mapfoldl(
fun
(#doc{} = Doc, Acc) ->
Json = ?JSON_ENCODE(couch_doc:to_json_obj(Doc, [revs, attachments])),
{Json, Acc + iolist_size(Json)};
(Doc, Acc) ->
{Doc, Acc + iolist_size(Doc)}
end,
byte_size(Prefix) + byte_size(Suffix) + length(DocList) - 1,
DocList
),
BodyFun = fun
(eof) ->
eof;
([]) ->
{ok, Suffix, eof};
([prefix | Rest]) ->
{ok, Prefix, Rest};
([Doc]) ->
{ok, Doc, []};
([Doc | RestDocs]) ->
{ok, [Doc, ","], RestDocs}
end,
Headers = [
{"Content-Length", Len},
{"Content-Type", "application/json"},
{"X-Couch-Full-Commit", FullCommit}
],
send_req(
HttpDb,
[
{method, post},
{path, "_bulk_docs"},
{body, {BodyFun, [prefix | Docs]}},
{headers, Headers}
],
fun
(201, _, Results) when is_list(Results) ->
{ok, bulk_results_to_errors(Results)};
(413, _, _) ->
{error, request_body_too_large};
(417, _, Results) when is_list(Results) ->
{ok, bulk_results_to_errors(Results)};
(ErrCode, _, ErrMsg) when is_integer(ErrCode) ->
{error, {bulk_docs_failed, ErrCode, ErrMsg}}
end
).
changes_since(
#httpdb{headers = Headers1, timeout = InactiveTimeout} = HttpDb,
Style,
StartSeq,
UserFun,
Options
) ->
Timeout = erlang:max(1000, InactiveTimeout div 3),
EncodedSeq = couch_replicator_utils:seq_encode(StartSeq),
BaseQArgs =
case get_value(continuous, Options, false) of
false ->
[{"feed", "normal"}];
true ->
[{"feed", "continuous"}]
end ++
[
{"style", atom_to_list(Style)},
{"since", EncodedSeq},
{"timeout", integer_to_list(Timeout)}
],
DocIds = get_value(doc_ids, Options),
Selector = get_value(selector, Options),
{QArgs, Method, Body, Headers} =
case {DocIds, Selector} of
{undefined, undefined} ->
QArgs1 = maybe_add_changes_filter_q_args(BaseQArgs, Options),
{QArgs1, get, [], Headers1};
{undefined, _} when is_tuple(Selector) ->
Headers2 = [{"Content-Type", "application/json"} | Headers1],
JsonSelector = ?JSON_ENCODE({[{<<"selector">>, Selector}]}),
{[{"filter", "_selector"} | BaseQArgs], post, JsonSelector, Headers2};
{_, undefined} when is_list(DocIds) ->
Headers2 = [{"Content-Type", "application/json"} | Headers1],
JsonDocIds = ?JSON_ENCODE({[{<<"doc_ids">>, DocIds}]}),
{[{"filter", "_doc_ids"} | BaseQArgs], post, JsonDocIds, Headers2}
end,
try
send_req(
HttpDb,
[
{method, Method},
{path, "_changes"},
{qs, QArgs},
{headers, Headers},
{body, Body},
{ibrowse_options, [{stream_to, {self(), once}}]}
],
fun
(200, _, DataStreamFun) ->
parse_changes_feed(Options, UserFun, DataStreamFun);
(405, _, _) when is_list(DocIds) ->
% CouchDB versions < 1.1.0 don't have the builtin
% _changes feed filter "_doc_ids" neither support POST
send_req(
HttpDb,
[
{method, get},
{path, "_changes"},
{qs, BaseQArgs},
{headers, Headers1},
{ibrowse_options, [{stream_to, {self(), once}}]}
],
fun(200, _, DataStreamFun2) ->
UserFun2 = fun
(#doc_info{id = Id} = DocInfo) ->
case lists:member(Id, DocIds) of
true ->
UserFun(DocInfo);
false ->
ok
end;
(LastSeq) ->
UserFun(LastSeq)
end,
parse_changes_feed(
Options,
UserFun2,
DataStreamFun2
)
end
);
(ErrCode, _, ErrMsg) when is_integer(ErrCode) ->
throw({retry_limit, {changes_req_failed, ErrCode, ErrMsg}})
end
)
catch
exit:{http_request_failed, _, _, max_backoff} ->
exit(max_backoff);
exit:{http_request_failed, _, _, {error, {connection_closed, mid_stream}}} ->
throw(retry_no_limit);
exit:{http_request_failed, _, _, _} = Error ->
throw({retry_limit, Error})
end.
% internal functions
maybe_add_changes_filter_q_args(BaseQS, Options) ->
case get_value(filter, Options) of
undefined ->
BaseQS;
FilterName ->
%% get list of view attributes
ViewFields0 = [atom_to_list(F) || F <- record_info(fields, mrargs)],
ViewFields = ["key" | ViewFields0],
{Params} = get_value(query_params, Options, {[]}),
[
{"filter", ?b2l(FilterName)}
| lists:foldl(
fun({K, V}, QSAcc) ->
Ks = couch_util:to_list(K),
case lists:keymember(Ks, 1, QSAcc) of
true ->
QSAcc;
false when FilterName =:= <<"_view">> ->
V1 =
case lists:member(Ks, ViewFields) of
true -> ?JSON_ENCODE(V);
false -> couch_util:to_list(V)
end,
[{Ks, V1} | QSAcc];
false ->
[{Ks, couch_util:to_list(V)} | QSAcc]
end
end,
BaseQS,
Params
)
]
end.
parse_changes_feed(Options, UserFun, DataStreamFun) ->
case get_value(continuous, Options, false) of
true ->
continuous_changes(DataStreamFun, UserFun);
false ->
EventFun = fun(Ev) ->
changes_ev1(Ev, fun(DocInfo, _) -> UserFun(DocInfo) end, [])
end,
json_stream_parse:events(DataStreamFun, EventFun)
end.
options_to_query_args(HttpDb, Path, Options0) ->
case lists:keytake(max_url_len, 1, Options0) of
false ->
MaxLen = ?MAX_URL_LEN,
Options = Options0;
{value, {max_url_len, MaxLen}, Options} ->
ok
end,
case lists:keytake(atts_since, 1, Options) of
false ->
options_to_query_args(Options, []);
{value, {atts_since, []}, Options2} ->
options_to_query_args(Options2, []);
{value, {atts_since, PAs}, Options2} ->
QueryArgs1 = options_to_query_args(Options2, []),
FullUrl = couch_replicator_httpc:full_url(
HttpDb, [{path, Path}, {qs, QueryArgs1}]
),
RevList = atts_since_arg(
length("GET " ++ FullUrl ++ " HTTP/1.1\r\n") +
% +6 = % encoded [ and ]
length("&atts_since=") + 6,
PAs,
MaxLen,
[]
),
[{"atts_since", ?b2l(iolist_to_binary(?JSON_ENCODE(RevList)))} | QueryArgs1]
end.
options_to_query_args([], Acc) ->
lists:reverse(Acc);
options_to_query_args([ejson_body | Rest], Acc) ->
options_to_query_args(Rest, Acc);
options_to_query_args([delay_commit | Rest], Acc) ->
options_to_query_args(Rest, Acc);
options_to_query_args([revs | Rest], Acc) ->
options_to_query_args(Rest, [{"revs", "true"} | Acc]);
options_to_query_args([{open_revs, all} | Rest], Acc) ->
options_to_query_args(Rest, [{"open_revs", "all"} | Acc]);
options_to_query_args([latest | Rest], Acc) ->
options_to_query_args(Rest, [{"latest", "true"} | Acc]);
options_to_query_args([{open_revs, Revs} | Rest], Acc) ->
JsonRevs = ?b2l(iolist_to_binary(?JSON_ENCODE(couch_doc:revs_to_strs(Revs)))),
options_to_query_args(Rest, [{"open_revs", JsonRevs} | Acc]);
options_to_query_args([{attachments, Bool} | Rest], Acc) when is_atom(Bool) ->
BoolStr = atom_to_list(Bool),
options_to_query_args(Rest, [{"attachments", BoolStr} | Acc]).
options_to_json_map([], #{} = Acc) ->
Acc;
options_to_json_map([latest | Rest], #{} = Acc) ->
options_to_json_map(Rest, Acc#{<<"latest">> => true});
options_to_json_map([revs | Rest], #{} = Acc) ->
options_to_json_map(Rest, Acc#{<<"revs">> => true});
options_to_json_map([{attachments, Bool} | Rest], #{} = Acc) when is_atom(Bool) ->
options_to_json_map(Rest, Acc#{<<"attachments">> => Bool}).
atts_since_arg(_UrlLen, [], _MaxLen, Acc) ->
lists:reverse(Acc);
atts_since_arg(UrlLen, [PA | Rest], MaxLen, Acc) ->
RevStr = couch_doc:rev_to_str(PA),
NewUrlLen =
case Rest of
[] ->
% plus 2 double quotes (% encoded)
UrlLen + size(RevStr) + 6;
_ ->
% plus 2 double quotes and a comma (% encoded)
UrlLen + size(RevStr) + 9
end,
case NewUrlLen >= MaxLen of
true ->
lists:reverse(Acc);
false ->
atts_since_arg(NewUrlLen, Rest, MaxLen, [RevStr | Acc])
end.
% TODO: A less verbose, more elegant and automatic restart strategy for
% the exported open_doc_revs/6 function. The restart should be
% transparent to the caller like any other Couch API function exported
% by this module.
receive_docs_loop(Streamer, Fun, Id, Revs, Ref, Acc) ->
try
% Left only for debugging purposes via an interactive or remote shell
erlang:put(open_doc_revs, {Id, Revs, Ref, Streamer}),
receive_docs(Streamer, Fun, Ref, Acc)
catch
error:{restart_open_doc_revs, NewRef} ->
receive_docs_loop(Streamer, Fun, Id, Revs, NewRef, Acc)
end.
receive_docs(Streamer, UserFun, Ref, UserAcc) ->
Streamer ! {get_headers, Ref, self()},
receive
{started_open_doc_revs, NewRef} ->
restart_remote_open_doc_revs(Ref, NewRef);
{headers, Ref, Headers} ->
case header_value("content-type", Headers) of
{"multipart/related", _} = ContentType ->
% Skip document body and attachment size limits validation here
% since these should be validated by the replication target
case
couch_doc:doc_from_multi_part_stream(
ContentType,
fun() -> receive_doc_data(Streamer, Ref) end,
Ref,
_ValidateDocLimits = false
)
of
{ok, Doc, WaitFun, Parser} ->
case run_user_fun(UserFun, {ok, Doc}, UserAcc, Ref) of
{ok, UserAcc2} ->
ok;
{skip, UserAcc2} ->
couch_httpd_multipart:abort_multipart_stream(Parser)
end,
WaitFun(),
receive_docs(Streamer, UserFun, Ref, UserAcc2)
end;
{"application/json", []} ->
Doc = couch_doc:from_json_obj(
?JSON_DECODE(receive_all(Streamer, Ref, []))
),
{_, UserAcc2} = run_user_fun(UserFun, {ok, Doc}, UserAcc, Ref),
receive_docs(Streamer, UserFun, Ref, UserAcc2);
{"application/json", [{"error", "true"}]} ->
{ErrorProps} = ?JSON_DECODE(receive_all(Streamer, Ref, [])),
Rev = get_value(<<"missing">>, ErrorProps),
Result = {{not_found, missing}, couch_doc:parse_rev(Rev)},
{_, UserAcc2} = run_user_fun(UserFun, Result, UserAcc, Ref),
receive_docs(Streamer, UserFun, Ref, UserAcc2)
end;
{done, Ref} ->
{ok, UserAcc}
end.
run_user_fun(UserFun, Arg, UserAcc, OldRef) ->
{Pid, Ref} = spawn_monitor(fun() ->
try UserFun(Arg, UserAcc) of
Resp ->
exit({exit_ok, Resp})
catch
throw:Reason ->
exit({exit_throw, Reason});
error:Reason ->
exit({exit_error, Reason});
exit:Reason ->
exit({exit_exit, Reason})
end
end),
receive
{started_open_doc_revs, NewRef} ->
erlang:demonitor(Ref, [flush]),
exit(Pid, kill),
restart_remote_open_doc_revs(OldRef, NewRef);
{'DOWN', Ref, process, Pid, {exit_ok, Ret}} ->
Ret;
{'DOWN', Ref, process, Pid, {exit_throw, Reason}} ->
throw(Reason);
{'DOWN', Ref, process, Pid, {exit_error, Reason}} ->
erlang:error(Reason);
{'DOWN', Ref, process, Pid, {exit_exit, Reason}} ->
erlang:exit(Reason)
end.
restart_remote_open_doc_revs(Ref, NewRef) ->
receive
{body_bytes, Ref, _} ->
restart_remote_open_doc_revs(Ref, NewRef);
{body_done, Ref} ->
restart_remote_open_doc_revs(Ref, NewRef);
{done, Ref} ->
restart_remote_open_doc_revs(Ref, NewRef);
{headers, Ref, _} ->
restart_remote_open_doc_revs(Ref, NewRef)
after 0 ->
erlang:error({restart_open_doc_revs, NewRef})
end.
remote_open_doc_revs_streamer_start(Parent) ->
receive
{get_headers, _Ref, Parent} ->
remote_open_doc_revs_streamer_start(Parent);
{next_bytes, _Ref, Parent} ->
remote_open_doc_revs_streamer_start(Parent)
after 0 ->
Parent ! {started_open_doc_revs, make_ref()}
end.
receive_all(Streamer, Ref, Acc) ->
Streamer ! {next_bytes, Ref, self()},
receive
{started_open_doc_revs, NewRef} ->
restart_remote_open_doc_revs(Ref, NewRef);
{body_bytes, Ref, Bytes} ->
receive_all(Streamer, Ref, [Bytes | Acc]);
{body_done, Ref} ->
lists:reverse(Acc)
end.
mp_parse_mixed(eof) ->
receive
{get_headers, Ref, From} ->
From ! {done, Ref}
end;
mp_parse_mixed({headers, H}) ->
receive
{get_headers, Ref, From} ->
From ! {headers, Ref, H}
end,
fun mp_parse_mixed/1;
mp_parse_mixed({body, Bytes}) ->
receive
{next_bytes, Ref, From} ->
From ! {body_bytes, Ref, Bytes}
end,
fun mp_parse_mixed/1;
mp_parse_mixed(body_end) ->
receive
{next_bytes, Ref, From} ->
From ! {body_done, Ref};
{get_headers, Ref, From} ->
self() ! {get_headers, Ref, From}
end,
fun mp_parse_mixed/1.
receive_doc_data(Streamer, Ref) ->
Streamer ! {next_bytes, Ref, self()},
receive
{body_bytes, Ref, Bytes} ->
{Bytes, fun() -> receive_doc_data(Streamer, Ref) end};
{body_done, Ref} ->
{<<>>, fun() -> receive_doc_data(Streamer, Ref) end}
end.
changes_ev1(object_start, UserFun, UserAcc) ->
fun(Ev) -> changes_ev2(Ev, UserFun, UserAcc) end.
changes_ev2({key, <<"results">>}, UserFun, UserAcc) ->
fun(Ev) -> changes_ev3(Ev, UserFun, UserAcc) end;
changes_ev2(_, UserFun, UserAcc) ->
fun(Ev) -> changes_ev2(Ev, UserFun, UserAcc) end.
changes_ev3(array_start, UserFun, UserAcc) ->
fun(Ev) -> changes_ev_loop(Ev, UserFun, UserAcc) end.
changes_ev_loop(object_start, UserFun, UserAcc) ->
fun(Ev) ->
json_stream_parse:collect_object(
Ev,
fun(Obj) ->
UserAcc2 = UserFun(json_to_doc_info(Obj), UserAcc),
fun(Ev2) -> changes_ev_loop(Ev2, UserFun, UserAcc2) end
end
)
end;
changes_ev_loop(array_end, _UserFun, _UserAcc) ->
fun(_Ev) -> changes_ev_done() end.
changes_ev_done() ->
fun(_Ev) -> changes_ev_done() end.
continuous_changes(DataFun, UserFun) ->
{DataFun2, _, Rest} = json_stream_parse:events(
DataFun,
fun(Ev) -> parse_changes_line(Ev, UserFun) end
),
continuous_changes(fun() -> {Rest, DataFun2} end, UserFun).
parse_changes_line(object_start, UserFun) ->
fun(Ev) ->
json_stream_parse:collect_object(
Ev,
fun(Obj) -> UserFun(json_to_doc_info(Obj)) end
)
end.
json_to_doc_info({Props}) ->
case get_value(<<"changes">>, Props) of
undefined ->
{last_seq, get_value(<<"last_seq">>, Props)};
Changes ->
RevsInfo0 = lists:map(
fun({Change}) ->
Rev = couch_doc:parse_rev(get_value(<<"rev">>, Change)),
Del = couch_replicator_utils:is_deleted(Change),
#rev_info{rev = Rev, deleted = Del}
end,
Changes
),
RevsInfo =
case get_value(<<"removed">>, Props) of
true ->
[_ | RevsInfo1] = RevsInfo0,
RevsInfo1;
_ ->
RevsInfo0
end,
#doc_info{
id = get_value(<<"id">>, Props),
high_seq = get_value(<<"seq">>, Props),
revs = RevsInfo
}
end.
bulk_results_to_errors(Results) ->
lists:reverse(
lists:foldl(
fun({Props}, Acc) ->
case get_value(<<"error">>, Props, get_value(error, Props)) of
undefined ->
Acc;
Error ->
Id = get_value(<<"id">>, Props, get_value(id, Props)),
Rev = get_value(<<"rev">>, Props, get_value(rev, Props)),
Reason = get_value(<<"reason">>, Props, get_value(reason, Props)),
[
{[
{id, Id},
{rev, rev_to_str(Rev)},
{error, Error},