Support `GET /_dbs_info` endpoint

Previously only `POST` with a list of keys was supported. The new `GET`
support just dumps all database info blobs in a single ordered response.

1 files changed, 48 insertions, 1 deletions

diff --git a/src/chttpd/src/chttpd_misc.erl b/src/chttpd/src/chttpd_misc.erl
index 186ec9ff0..b181f3c25 100644
--- a/src/chttpd/src/chttpd_misc.erl
+++ b/src/chttpd/src/chttpd_misc.erl
@@ -157,6 +157,37 @@ all_dbs_callback({error, Reason}, #vacc{resp=Resp0}=Acc) ->
     {ok, Resp1} = chttpd:send_delayed_error(Resp0, Reason),
     {ok, Acc#vacc{resp=Resp1}}.
 
+handle_dbs_info_req(#httpd{method = 'GET'} = Req) ->
+    ok = chttpd:verify_is_server_admin(Req),
+
+    #mrargs{
+        start_key = StartKey,
+        end_key = EndKey,
+        direction = Dir,
+        limit = Limit,
+        skip = Skip
+    } = couch_mrview_http:parse_params(Req, undefined),
+
+    Options = [
+        {start_key, StartKey},
+        {end_key, EndKey},
+        {dir, Dir},
+        {limit, Limit},
+        {skip, Skip}
+    ],
+
+    % TODO: Figure out if we can't calculate a valid
+    % ETag for this request. \xFFmetadataVersion won't
+    % work as we don't bump versions on size changes
+
+    {ok, Resp} = chttpd:start_delayed_json_response(Req, 200, []),
+    Callback = fun dbs_info_callback/2,
+    Acc = #vacc{req = Req, resp = Resp},
+    {ok, Resp} = fabric2_db:list_dbs_info(Callback, Acc, Options),
+    case is_record(Resp, vacc) of
+        true -> {ok, Resp#vacc.resp};
+        _ -> {ok, Resp}
+    end;
 handle_dbs_info_req(#httpd{method='POST', user_ctx=UserCtx}=Req) ->
     chttpd:validate_ctype(Req, "application/json"),
     Props = chttpd:json_body_obj(Req),
@@ -188,7 +219,23 @@ handle_dbs_info_req(#httpd{method='POST', user_ctx=UserCtx}=Req) ->
     send_chunk(Resp, "]"),
     chttpd:end_json_response(Resp);
 handle_dbs_info_req(Req) ->
-    send_method_not_allowed(Req, "POST").
+    send_method_not_allowed(Req, "GET,HEAD,POST").
+
+dbs_info_callback({meta, _Meta}, #vacc{resp = Resp0} = Acc) ->
+    {ok, Resp1} = chttpd:send_delayed_chunk(Resp0, "["),
+    {ok, Acc#vacc{resp = Resp1}};
+dbs_info_callback({row, Props}, #vacc{resp = Resp0} = Acc) ->
+    Prepend = couch_mrview_http:prepend_val(Acc),
+    Chunk = [Prepend, ?JSON_ENCODE({Props})],
+    {ok, Resp1} = chttpd:send_delayed_chunk(Resp0, Chunk),
+    {ok, Acc#vacc{prepend = ",", resp = Resp1}};
+dbs_info_callback(complete, #vacc{resp = Resp0} = Acc) ->
+    {ok, Resp1} = chttpd:send_delayed_chunk(Resp0, "]"),
+    {ok, Resp2} = chttpd:end_delayed_json_response(Resp1),
+    {ok, Acc#vacc{resp = Resp2}};
+dbs_info_callback({error, Reason}, #vacc{resp = Resp0} = Acc) ->
+    {ok, Resp1} = chttpd:send_delayed_error(Resp0, Reason),
+    {ok, Acc#vacc{resp = Resp1}}.
 
 handle_task_status_req(#httpd{method='GET'}=Req) ->
     ok = chttpd:verify_is_server_admin(Req),