Merge pull request DiversityTemplating#10 from DiversityTemplating/be…

…tter-file-handling

Changed from os:cmd to erlang:open_port so we can stream the result. Thi...

src/component_handler.erl

@@ -5,8 +5,7 @@
 -export([handle/2]).
 -export([terminate/3]).
 
--record(state, {
-}).
+-record(state, {}).
 
 -define(JSON_HEADER, [{<<"content-type">>, <<"application/json">>}, {<<"Access-Control-Allow-Origin">>, <<"*">>}]).
 
@@ -34,10 +33,9 @@ handle_get(Req, _State=#state{}) ->
                 Tag = expand_tag(PartialTag, Tags),
                 case Routes of
                     [] ->
-                        Data = divapi_cache:get_diversity_json(ComponentName, Tag),
-                        case Data of
+                        case divapi_cache:get_diversity_json(ComponentName, Tag) of
                             undefined -> cowboy_req:reply(404, Req3);
-                            _ -> cowboy_req:reply(200, ?JSON_HEADER, Data, Req3)
+                            Data      -> cowboy_req:reply(200, ?JSON_HEADER, Data, Req3)
                         end;
                     [Settings] when Settings =:= <<"settings">>;
                                     Settings =:= <<"settingsForm">> ->
@@ -48,13 +46,19 @@ handle_get(Req, _State=#state{}) ->
                         cowboy_req:reply(200, ?JSON_HEADER, SettingsJson, Req3);
                     [<<"files">> | Path] ->
                         File = filename:join(Path),
-                        FileData = git_utils:get_file(ComponentName, undefined, Tag, File),
-                        {Mime, Type, []} = cow_mimetypes:all(File),
-                        Header = [{<<"content-type">>, << Mime/binary, "/", Type/binary >>}],
-                        cowboy_req:reply(200, Header, FileData, Req3);
+                        FileBin = git_utils:get_file(ComponentName, undefined, Tag, File),
+                        case FileBin of
+                            undefined ->
+                                cowboy_req:reply(404, Req3);
+                            error ->
+                                cowboy_req:reply(500, Req3);
+                            _ ->
+                                {Mime, Type, []} = cow_mimetypes:all(File),
+                                Headers = [{<<"content-type">>, << Mime/binary, "/", Type/binary >>}],
+                                cowboy_req:reply(200, Headers, FileBin, Req3)
+                        end;
                     _ ->
                         cowboy_req:reply(404, Req3)
-
                 end;
             _ ->
                 cowboy_req:reply(404, Req3)
@@ -71,7 +75,6 @@ expand_tag(Tag, Tags) ->
             <<Tag/binary, ".", PatchNr/binary>>
     end.
 
-
 handle_post(Req, _State=#state{}) ->
     {ComponentName, Req2} = cowboy_req:binding(component, Req),
     {PathInfo, Req3} = cowboy_req:path_info(Req2),

src/git_utils.erl

@@ -6,9 +6,16 @@
 %% @doc Returns a list with all tags in a git repository
 -spec tags(binary(), binary()) -> [binary()].
 tags(RepoName, RepoUrl) ->
-    Cmd = "tag",
-    ResultString = get_git_result(RepoName, RepoUrl, Cmd),
-    [list_to_binary(Tag) || Tag <- string:tokens(ResultString, "\n")].
+    Cmd = <<"git tag">>,
+    case get_git_result(RepoName, RepoUrl, Cmd) of
+        error ->
+            [];
+        <<>>  ->
+            [];
+        ResultBin ->
+            Res = re:split(ResultBin, <<"\n">>),
+            lists:droplast(Res)
+    end.
 
 %% @doc Returns the diversity.json for a tag in a repo
 -spec get_diversity_json(binary(), binary(), binary()) -> binary().
@@ -20,48 +27,62 @@ get_diversity_json(RepoName, RepoUrl, Tag) ->
 git_refresh_repo(RepoName) ->
     {ok, RepoDir} = application:get_env(divapi, repo_dir),
     GitRepoName =  RepoDir ++ "/" ++ binary_to_list(RepoName) ++ ".git",
-    file:set_cwd(GitRepoName),
-    Cmd = "fetch origin master:master",
-    git_cmd(Cmd).
+    Cmd = <<"git fetch origin master:master">>,
+    git_cmd(Cmd, GitRepoName).
 
 get_file(RepoName, RepoUrl, Tag, FilePath) ->
     get_git_file(RepoName, RepoUrl, Tag, FilePath).
 
-
 %% ----------------------------------------------------------------------------
 %% Internal stuff
 %% ----------------------------------------------------------------------------
+
+%% @doc Retrieves the file from the bare git repo and the specific tag.
+-spec get_git_file(RepoName :: binary(), RepoUrl :: binary(), Tag :: binary(),
+                   FilePath :: binary) -> binary() | undefined.
 get_git_file(RepoName, RepoUrl, Tag, FilePath) ->
-    Cmd = "show " ++ binary_to_list(Tag) ++ ":" ++ binary_to_list(FilePath),
+    Cmd = <<"git --no-pager show ", Tag/binary, ":", FilePath/binary>>,
     case get_git_result(RepoName, RepoUrl, Cmd) of
-        "fatal" ++ _ -> undefined;
-        Result -> list_to_binary(Result)
+        FileBin when is_binary(FileBin) -> FileBin;
+        error                           -> undefined;
+        ok                              -> <<>> %% Command succesful but empty result!
     end.
 
 get_git_result(RepoName, RepoUrl, Cmd) ->
     {ok, RepoDir} = application:get_env(divapi, repo_dir),
-    GitRepoName =  RepoDir ++ "/" ++ binary_to_list(RepoName) ++ ".git",
+    GitRepoDir =  RepoDir ++ "/" ++ binary_to_list(RepoName) ++ ".git",
     %% Clone git repo if non-existing in configured dir
-    case filelib:is_dir(GitRepoName) of
+    case filelib:is_dir(GitRepoDir) of
         false ->
             RepoUrl2 = get_repo_url(RepoName, RepoUrl),
             clone_bare(binary_to_list(RepoUrl2));
         true ->
             %% Checkout not needed
             ok
     end,
-    file:set_cwd(GitRepoName),
-    git_cmd(Cmd).
+    git_cmd(Cmd, GitRepoDir).
 
 clone_bare(RepoUrl) ->
     {ok, RepoDir} = application:get_env(divapi, repo_dir),
-    filelib:ensure_dir(RepoDir ++ "/"),
-    file:set_cwd(RepoDir),
-    Cmd = "clone --bare " ++ RepoUrl,
-    git_cmd(Cmd).
+    %% Ensure it exists if not try to create it.
+    ok = filelib:ensure_dir(RepoDir ++ "/"),
+    Cmd = <<"git clone --bare ", (list_to_binary(RepoUrl))/binary>>,
+    git_cmd(Cmd, RepoDir).
 
 get_repo_url(RepoName, undefined) -> gitlab_utils:get_public_project_url(RepoName);
 get_repo_url(_, RepoUrl) -> RepoUrl.
 
-git_cmd(Cmd) ->
-    os:cmd("git " ++ Cmd).
+git_cmd(Cmd, WorkingDir) ->
+    Port = erlang:open_port({spawn, Cmd}, [exit_status, {cd, WorkingDir}, binary, use_stdio]),
+    wait_for_file(Port, <<>>).
+
+wait_for_file(Port, File) ->
+    receive
+        {Port, {data, Chunk}} ->
+            wait_for_file(Port, <<File/binary, Chunk/binary>>);
+        {_ , {exit_status, 0}} ->
+            File;
+        {_, {exit_status, _}} ->
+            %% Either not a git repo or operation failed. No need to close port it' already done.
+            error
+    end.