fix(ft): improve typespecs

apps/emqx_ft/src/emqx_ft_assembler.erl

@@ -26,7 +26,7 @@
 -record(st, {
     storage :: _Storage,
     transfer :: emqx_ft:transfer(),
-    assembly :: _TODO,
+    assembly :: emqx_ft_assembly:t(),
     file :: {file:filename(), io:device(), term()} | undefined,
     hash
 }).

apps/emqx_ft/src/emqx_ft_assembly.erl

@@ -25,16 +25,43 @@
 -export([coverage/1]).
 -export([properties/1]).
 
+-export_type([t/0]).
+
+-type filemeta() :: emqx_ft:filemeta().
+-type filefrag() :: emqx_ft_storage_fs:filefrag().
+-type filefrag(T) :: emqx_ft_storage_fs:filefrag(T).
+-type segmentinfo() :: emqx_ft_storage_fs:segmentinfo().
+
 -record(asm, {
-    status :: _TODO,
-    coverage :: _TODO,
-    properties :: _TODO,
-    meta :: _TODO,
-    % orddict:orddict(K, V)
-    segs :: _TODO,
-    size
+    status :: status(),
+    coverage :: coverage() | undefined,
+    properties :: properties() | undefined,
+    meta :: orddict:orddict(
+        filemeta(),
+        {node(), filefrag({filemeta, filemeta()})}
+    ),
+    segs :: orddict:orddict(
+        {emqx_ft:offset(), _Locality, _MEnd, node()},
+        filefrag({segment, segmentinfo()})
+    ),
+    size :: emqx_ft:bytes()
 }).
 
+-type status() ::
+    {incomplete, {missing, _}}
+    | complete
+    | {error, {inconsistent, _}}.
+
+-type coverage() :: [{node(), filefrag({segment, segmentinfo()})}].
+
+-type properties() :: #{
+    %% Node where "most" of the segments are located.
+    dominant => node()
+}.
+
+-opaque t() :: #asm{}.
+
+-spec new(emqx_ft:bytes()) -> t().
 new(Size) ->
     #asm{
         status = {incomplete, {missing, filemeta}},
@@ -43,6 +70,7 @@ new(Size) ->
         size = Size
     }.
 
+-spec append(t(), node(), filefrag() | [filefrag()]) -> t().
 append(Asm, Node, Fragments) when is_list(Fragments) ->
     lists:foldl(fun(F, AsmIn) -> append(AsmIn, Node, F) end, Asm, Fragments);
 append(Asm, Node, Fragment = #{fragment := {filemeta, _}}) ->
@@ -50,6 +78,7 @@ append(Asm, Node, Fragment = #{fragment := {filemeta, _}}) ->
 append(Asm, Node, Segment = #{fragment := {segment, _}}) ->
     append_segmentinfo(Asm, Node, Segment).
 
+-spec update(t()) -> t().
 update(Asm) ->
     case status(meta, Asm) of
         {complete, _Meta} ->
@@ -67,15 +96,18 @@ update(Asm) ->
             Asm#asm{status = Status}
     end.
 
+-spec status(t()) -> status().
 status(#asm{status = Status}) ->
     Status.
 
+-spec filemeta(t()) -> filemeta().
 filemeta(Asm) ->
     case status(meta, Asm) of
         {complete, Meta} -> Meta;
         _Other -> undefined
     end.
 
+-spec coverage(t()) -> coverage() | undefined.
 coverage(#asm{coverage = Coverage}) ->
     Coverage.
 

apps/emqx_ft/src/emqx_ft_storage_fs.erl

@@ -80,11 +80,18 @@
 
 -type storage() :: emqx_ft_storage:storage().
 
+-type file_error() ::
+    file:posix()
+    %% Filename is incompatible with the backing filesystem.
+    | badarg
+    %% System limit (e.g. number of ports) reached.
+    | system_limit.
+
 %% Store manifest in the backing filesystem.
 %% Atomic operation.
 -spec store_filemeta(storage(), transfer(), filemeta()) ->
     % Quota? Some lower level errors?
-    ok | {error, conflict} | {error, _TODO}.
+    ok | {error, conflict} | {error, file_error()}.
 store_filemeta(Storage, Transfer, Meta) ->
     % TODO safeguard against bad clientids / fileids.
     Filepath = mk_filepath(Storage, Transfer, [?FRAGDIR], ?MANIFEST),
@@ -110,7 +117,7 @@ store_filemeta(Storage, Transfer, Meta) ->
 -spec store_segment(storage(), transfer(), segment()) ->
     % Where is the checksum gets verified? Upper level probably.
     % Quota? Some lower level errors?
-    ok | {error, _TODO}.
+    ok | {error, file_error()}.
 store_segment(Storage, Transfer, Segment = {_Offset, Content}) ->
     Filepath = mk_filepath(Storage, Transfer, [?FRAGDIR], mk_segment_filename(Segment)),
     write_file_atomic(Storage, Transfer, Filepath, Content).
@@ -118,7 +125,8 @@ store_segment(Storage, Transfer, Segment = {_Offset, Content}) ->
 -spec list(storage(), transfer(), _What :: fragment | result) ->
     % Some lower level errors? {error, notfound}?
     % Result will contain zero or only one filemeta.
-    {ok, [filefrag({filemeta, filemeta()} | {segment, segmentinfo()})]} | {error, _TODO}.
+    {ok, [filefrag({filemeta, filemeta()} | {segment, segmentinfo()})]}
+    | {error, file_error()}.
 list(Storage, Transfer, What) ->
     Dirname = mk_filedir(Storage, Transfer, get_subdirs_for(What)),
     case file:list_dir(Dirname) of
@@ -146,7 +154,7 @@ get_filefrag_fun_for(result) ->
     fun mk_result_filefrag/2.
 
 -spec pread(storage(), transfer(), filefrag(), offset(), _Size :: non_neg_integer()) ->
-    {ok, _Content :: iodata()} | {error, _TODO}.
+    {ok, _Content :: iodata()} | {error, eof} | {error, file_error()}.
 pread(_Storage, _Transfer, Frag, Offset, Size) ->
     Filepath = maps:get(path, Frag),
     case file:open(Filepath, [read, raw, binary]) of
@@ -168,7 +176,6 @@ pread(_Storage, _Transfer, Frag, Offset, Size) ->
     end.
 
 -spec assemble(storage(), transfer(), emqx_ft:bytes()) ->
-    % {ok, _Assembler :: pid()} | {error, incomplete} | {error, badrpc} | {error, _TODO}.
     {async, _Assembler :: pid()} | {error, _TODO}.
 assemble(Storage, Transfer, Size) ->
     % TODO: ask cluster if the transfer is already assembled
@@ -321,7 +328,7 @@ read_transferinfo(Storage, Transfer, Acc) ->
 -type handle() :: {file:name(), io:device(), crypto:hash_state()}.
 
 -spec open_file(storage(), transfer(), filemeta()) ->
-    {ok, handle()} | {error, _TODO}.
+    {ok, handle()} | {error, file_error()}.
 open_file(Storage, Transfer, Filemeta) ->
     Filename = maps:get(name, Filemeta),
     TempFilepath = mk_temp_filepath(Storage, Transfer, Filename),
@@ -335,7 +342,7 @@ open_file(Storage, Transfer, Filemeta) ->
     end.
 
 -spec write(handle(), iodata()) ->
-    {ok, handle()} | {error, _TODO}.
+    {ok, handle()} | {error, file_error()}.
 write({Filepath, IoDevice, Ctx}, IoData) ->
     case file:write(IoDevice, IoData) of
         ok ->
@@ -345,7 +352,7 @@ write({Filepath, IoDevice, Ctx}, IoData) ->
     end.
 
 -spec complete(storage(), transfer(), filemeta(), handle()) ->
-    ok | {error, {checksum, _Algo, _Computed}} | {error, _TODO}.
+    ok | {error, {checksum, _Algo, _Computed}} | {error, file_error()}.
 complete(Storage, Transfer, Filemeta, Handle = {Filepath, IoDevice, Ctx}) ->
     TargetFilepath = mk_filepath(Storage, Transfer, [?RESULTDIR], maps:get(name, Filemeta)),
     case verify_checksum(Ctx, Filemeta) of