Handle provider options as in the spec.

src/aws_credentials_ec2.erl

@@ -31,7 +31,7 @@
 
 -export([fetch/1]).
 
--spec fetch(aws_credentials_provider:options()) ->
+-spec fetch(any()) ->
         {error, _}
       | {ok, aws_credentials:credentials(), aws_credentials_provider:expiration()}.
 fetch(_Options) ->

src/aws_credentials_file.erl

@@ -21,10 +21,11 @@
 %%
 %% Environment parameters:
 %% <ul>
-%%   <li> &lt;&lt;"credentials_path"&gt;&gt; - this is the base path to the both CLI configuration files.
+%%   <li> 'credential_path' - this is the base path to the both CLI configuration files.
 %%   And based on this path, credentials file should exist and config file is optional.
-%%   By default this is `~/.aws/'</li>
-%%   <li> &lt;&lt;"profile"&gt;&gt; - this is the desired profile to use in the credentials file.
+%%   By default this is "~/.aws/"</li>
+%%   <li> 'profile'; - this is the desired profile to use in the credentials file.
+%%   The profile can also be provided via the "AWS_PROFILE" os env.
 %%   By default this is &lt;&lt;"default"&gt;&gt;</li>
 %% </ul>
 %% @end
@@ -33,7 +34,12 @@
 
 -export([fetch/1]).
 
--spec fetch(aws_credentials_provider:options()) ->
+-type options() :: #{ credential_path => string()
+                    , profile => binary()
+                    }.
+-export_type([options/0]).
+
+-spec fetch(options()) ->
         {error, any()} | {ok, aws_credentials:credentials(), 'infinity'}.
 fetch(Options) ->
     FilePath = get_file_path(Options),
@@ -62,7 +68,7 @@ maybe_path_from_env(EnvVar, FilePath) ->
         {_, Path} -> Path
     end.
 
--spec get_file_path(aws_credentials_provider:options()) -> {error, any()} | string().
+-spec get_file_path(options()) -> {error, any()} | string().
 get_file_path(Options) ->
   case maps:get(credential_path, Options, undefined) of
     undefined -> maybe_add_home("/.aws/");
@@ -79,7 +85,7 @@ maybe_add_home(Path) ->
 -spec maybe_add_region(
         {error, any()} | {ok, aws_credentials:credentials(), 'infinity'},
         {error, any()} | string(),
-        aws_credentials_provider:options()
+        options()
       ) -> {ok, aws_credentials:credentials(), 'infinity'}.
 maybe_add_region({error, _} = Error, _Config, _Options) -> Error;
 maybe_add_region(Result, {error, _Error}, _Options) -> Result;
@@ -98,7 +104,7 @@ check_path_exists(Path) ->
       true -> Path
     end.
 
--spec parse_credentials_file(string(), aws_credentials_provider:options()) ->
+-spec parse_credentials_file(string(), options()) ->
         {error, any()} | {ok, aws_credentials:credentials(), 'infinity'}.
 parse_credentials_file(Path, Options) ->
     {ok, F} = file:read_file(Path),
@@ -123,7 +129,7 @@ parse_credentials_file(Path, Options) ->
             end
     end.
 
--spec parse_config_file(string(), aws_credentials_provider:options()) ->
+-spec parse_config_file(string(), options()) ->
         {error, any()} | {ok, map()}.
 parse_config_file(Path, Options) ->
     {ok, F} = file:read_file(Path),
@@ -138,7 +144,7 @@ read_from_profile(File, Profile) ->
         Map -> {ok, Map}
     end.
 
--spec desired_profile(aws_credentials_provider:options()) -> binary().
+-spec desired_profile(options()) -> binary().
 desired_profile(Options) ->
     case {os:getenv("AWS_PROFILE"), maps:get(profile, Options, undefined)} of
         {false, undefined} -> <<"default">>;

src/aws_credentials_provider.erl

@@ -30,7 +30,19 @@
 
 -export([fetch/0, fetch/1]).
 
--type options() :: #{provider() => map()}.
+%% `credential_path' and `profile' are treated as common options,
+%% and their values are inherited by `provider_specific_options()'
+%% unless the same options exist in `provider_specific_options()'.
+%% Note: This behaviour is for compatibility reason only, and
+%% do not add any further common options.
+-type options() :: #{ credential_path => string()
+                    , profile => binary()
+                    , provider() => provider_specific_options()
+                    }.
+-type provider_specific_options() :: #{ credential_path => string()
+                                      , profile => binary()
+                                      , any() => any()
+                                      }.
 -type expiration() :: binary() | pos_integer() | infinity.
 -type provider() :: aws_credentials_env
                   | aws_credentials_file
@@ -40,7 +52,7 @@
 -type error_log() :: [{provider(), term()}].
 -export_type([ options/0, expiration/0, provider/0 ]).
 
--callback fetch(options()) ->
+-callback fetch(provider_specific_options()) ->
   {ok, aws_credentials:credentials(), expiration()} | {error, any()}.
 
 -include_lib("kernel/include/logger.hrl").
@@ -74,7 +86,8 @@ evaluate_providers([], _Options, []) ->
 evaluate_providers([], _Options, Errors) when is_list(Errors) ->
     {error, lists:reverse(Errors)};
 evaluate_providers([ Provider | Providers ], Options, Errors) ->
-    case Provider:fetch(Options) of
+    ProviderOptions = get_provider_specific_options(Provider, Options),
+    case Provider:fetch(ProviderOptions) of
         {error, _} = Error ->
             evaluate_providers(Providers, Options, [{Provider, Error} | Errors]);
         {ok, Credentials, Expiration} ->
@@ -87,3 +100,12 @@ get_env(Key, Default) ->
         undefined -> Default;
         {ok, Value} -> Value
     end.
+
+-spec get_provider_specific_options(provider(), options()) -> provider_specific_options().
+get_provider_specific_options(Provider, Options) ->
+    ProviderSpecificOptions = maps:get(Provider, Options, #{}),
+    IsCommonOptions = fun(profile, _) -> true; (credential_path, _) -> true; (_, _) -> false end,
+    CommonOptions = maps:filter(IsCommonOptions, Options),
+    %% If an option exists in both ProviderSpecificOptions and CommonOptions,
+    %% the value in ProviderSpecificOptions should be adopted.
+    maps:merge(CommonOptions, ProviderSpecificOptions).