Fix handling of {:system, "AWS_ROLE_ARN"}

config/config.exs

@@ -1,6 +1,6 @@
 # This file is responsible for configuring your application
 # and its dependencies with the aid of the Mix.Config module.
-use Mix.Config
+import Config
 
 # This configuration is loaded before any dependency and is restricted
 # to this project. If another project depends on this project, this

lib/ex_aws/sts/auth_cache/assume_role_credentials_adapter.ex

@@ -11,7 +11,12 @@ defmodule ExAws.STS.AuthCache.AssumeRoleCredentialsAdapter do
     adapt_auth_config(auth, profile, expiration, &load_credentials/1)
   end
 
-  def adapt_auth_config(%{source_profile: source_profile} = auth, _, expiration, loader) do
+  def adapt_auth_config(
+        %{source_profile: source_profile, role_arn: _} = auth,
+        _,
+        expiration,
+        loader
+      ) do
     source_profile_auth = loader.(source_profile)
     get_security_credentials(auth, source_profile_auth, expiration)
   end
@@ -28,17 +33,20 @@ defmodule ExAws.STS.AuthCache.AssumeRoleCredentialsAdapter do
         _ -> [duration: duration]
       end
 
-    assume_role_request =
-      ExAws.STS.assume_role(auth.role_arn, role_session_name, assume_role_options)
+    assume_role_config =
+      ExAws.Config.new(:sts, Map.put(source_profile_auth, :role_arn, auth.role_arn))
+
+    role_arn = assume_role_config.role_arn
 
-    assume_role_config = ExAws.Config.new(:sts, source_profile_auth)
+    assume_role_request =
+      ExAws.STS.assume_role(role_arn, role_session_name, assume_role_options)
 
     with {:ok, result} <- ExAws.request(assume_role_request, assume_role_config) do
       %{
         access_key_id: result.body.access_key_id,
         secret_access_key: result.body.secret_access_key,
         security_token: result.body.session_token,
-        role_arn: auth.role_arn,
+        role_arn: role_arn,
         role_session_name: role_session_name,
         source_profile: auth.source_profile
       }

mix.lock

@@ -1,23 +1,25 @@
 %{
-  "briefly": {:hex, :briefly, "0.3.0", "16e6b76d2070ebc9cbd025fa85cf5dbaf52368c4bd896fb482b5a6b95a540c2f", [:mix], [], "hexpm", "c6ebf8fc3dcd4950dd10c03e953fb4f553a8bcf0ff4c8c40d71542434cd7e046"},
-  "certifi": {:hex, :certifi, "2.6.1", "dbab8e5e155a0763eea978c913ca280a6b544bfa115633fa20249c3d396d9493", [:rebar3], [], "hexpm", "524c97b4991b3849dd5c17a631223896272c6b0af446778ba4675a1dff53bb7e"},
+  "briefly": {:hex, :briefly, "0.5.1", "ee10d48da7f79ed2aebdc3e536d5f9a0c3e36ff76c0ad0d4254653a152b13a8a", [:mix], [], "hexpm", "bd684aa92ad8b7b4e0d92c31200993c4bc1469fc68cd6d5f15144041bd15cb57"},
+  "certifi": {:hex, :certifi, "2.15.0", "0e6e882fcdaaa0a5a9f2b3db55b1394dba07e8d6d9bcad08318fb604c6839712", [:rebar3], [], "hexpm", "b147ed22ce71d72eafdad94f055165c1c182f61a2ff49df28bcc71d1d5b94a60"},
   "earmark": {:hex, :earmark, "1.3.2", "b840562ea3d67795ffbb5bd88940b1bed0ed9fa32834915125ea7d02e35888a5", [:mix], [], "hexpm", "e3be2bc3ae67781db529b80aa7e7c49904a988596e2dbff897425b48b3581161"},
-  "earmark_parser": {:hex, :earmark_parser, "1.4.13", "0c98163e7d04a15feb62000e1a891489feb29f3d10cb57d4f845c405852bbef8", [:mix], [], "hexpm", "d602c26af3a0af43d2f2645613f65841657ad6efc9f0e361c3b6c06b578214ba"},
-  "ex_aws": {:hex, :ex_aws, "2.2.3", "f9bb1b04aaed3270f08c99d0268ff2c6596edb3a4a8792d18ffd37a74dd4810d", [:mix], [{:configparser_ex, "~> 4.0", [hex: :configparser_ex, repo: "hexpm", optional: true]}, {:hackney, "~> 1.16", [hex: :hackney, repo: "hexpm", optional: true]}, {:jason, "~> 1.1", [hex: :jason, repo: "hexpm", optional: true]}, {:jsx, "~> 3.0", [hex: :jsx, repo: "hexpm", optional: true]}, {:sweet_xml, "~> 0.6", [hex: :sweet_xml, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "8ddf1da94624e5f92afe36d4146086f72d85bb15998cec137c1fd854a3f04bc4"},
-  "ex_doc": {:hex, :ex_doc, "0.24.2", "e4c26603830c1a2286dae45f4412a4d1980e1e89dc779fcd0181ed1d5a05c8d9", [:mix], [{:earmark_parser, "~> 1.4.0", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "e134e1d9e821b8d9e4244687fb2ace58d479b67b282de5158333b0d57c6fb7da"},
-  "hackney": {:hex, :hackney, "1.17.4", "99da4674592504d3fb0cfef0db84c3ba02b4508bae2dff8c0108baa0d6e0977c", [:rebar3], [{:certifi, "~>2.6.1", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "~>6.1.0", [hex: :idna, repo: "hexpm", optional: false]}, {:metrics, "~>1.0.0", [hex: :metrics, repo: "hexpm", optional: false]}, {:mimerl, "~>1.1", [hex: :mimerl, repo: "hexpm", optional: false]}, {:parse_trans, "3.3.1", [hex: :parse_trans, repo: "hexpm", optional: false]}, {:ssl_verify_fun, "~>1.1.0", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}, {:unicode_util_compat, "~>0.7.0", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "de16ff4996556c8548d512f4dbe22dd58a587bf3332e7fd362430a7ef3986b16"},
+  "earmark_parser": {:hex, :earmark_parser, "1.4.44", "f20830dd6b5c77afe2b063777ddbbff09f9759396500cdbe7523efd58d7a339c", [:mix], [], "hexpm", "4778ac752b4701a5599215f7030989c989ffdc4f6df457c5f36938cc2d2a2750"},
+  "ex_aws": {:hex, :ex_aws, "2.6.1", "194582c7b09455de8a5ab18a0182e6dd937d53df82be2e63c619d01bddaccdfa", [:mix], [{:configparser_ex, "~> 5.0", [hex: :configparser_ex, repo: "hexpm", optional: true]}, {:hackney, "~> 1.16", [hex: :hackney, repo: "hexpm", optional: true]}, {:jason, "~> 1.1", [hex: :jason, repo: "hexpm", optional: true]}, {:jsx, "~> 2.8 or ~> 3.0", [hex: :jsx, repo: "hexpm", optional: true]}, {:mime, "~> 1.2 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:req, "~> 0.5.10 or ~> 0.6 or ~> 1.0", [hex: :req, repo: "hexpm", optional: true]}, {:sweet_xml, "~> 0.7", [hex: :sweet_xml, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "67842a08c90a1d9a09dbe4ac05754175c7ca253abe4912987c759395d4bd9d26"},
+  "ex_doc": {:hex, :ex_doc, "0.40.1", "67542e4b6dde74811cfd580e2c0149b78010fd13001fda7cfeb2b2c2ffb1344d", [:mix], [{:earmark_parser, "~> 1.4.44", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_c, ">= 0.1.0", [hex: :makeup_c, repo: "hexpm", optional: true]}, {:makeup_elixir, "~> 0.14 or ~> 1.0", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1 or ~> 1.0", [hex: :makeup_erlang, repo: "hexpm", optional: false]}, {:makeup_html, ">= 0.1.0", [hex: :makeup_html, repo: "hexpm", optional: true]}], "hexpm", "bcef0e2d360d93ac19f01a85d58f91752d930c0a30e2681145feea6bd3516e00"},
+  "hackney": {:hex, :hackney, "1.25.0", "390e9b83f31e5b325b9f43b76e1a785cbdb69b5b6cd4e079aa67835ded046867", [:rebar3], [{:certifi, "~> 2.15.0", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "~> 6.1.0", [hex: :idna, repo: "hexpm", optional: false]}, {:metrics, "~> 1.0.0", [hex: :metrics, repo: "hexpm", optional: false]}, {:mimerl, "~> 1.4", [hex: :mimerl, repo: "hexpm", optional: false]}, {:parse_trans, "3.4.1", [hex: :parse_trans, repo: "hexpm", optional: false]}, {:ssl_verify_fun, "~> 1.1.0", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}, {:unicode_util_compat, "~> 0.7.1", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "7209bfd75fd1f42467211ff8f59ea74d6f2a9e81cbcee95a56711ee79fd6b1d4"},
   "idna": {:hex, :idna, "6.1.1", "8a63070e9f7d0c62eb9d9fcb360a7de382448200fbbd1b106cc96d3d8099df8d", [:rebar3], [{:unicode_util_compat, "~>0.7.0", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "92376eb7894412ed19ac475e4a86f7b413c1b9fbb5bd16dccd57934157944cea"},
-  "jason": {:hex, :jason, "1.2.2", "ba43e3f2709fd1aa1dce90aaabfd039d000469c05c56f0b8e31978e03fa39052", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "18a228f5f0058ee183f29f9eae0805c6e59d61c3b006760668d8d18ff0d12179"},
-  "makeup": {:hex, :makeup, "1.0.5", "d5a830bc42c9800ce07dd97fa94669dfb93d3bf5fcf6ea7a0c67b2e0e4a7f26c", [:mix], [{:nimble_parsec, "~> 0.5 or ~> 1.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "cfa158c02d3f5c0c665d0af11512fed3fba0144cf1aadee0f2ce17747fba2ca9"},
-  "makeup_elixir": {:hex, :makeup_elixir, "0.15.1", "b5888c880d17d1cc3e598f05cdb5b5a91b7b17ac4eaf5f297cb697663a1094dd", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.1", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "db68c173234b07ab2a07f645a5acdc117b9f99d69ebf521821d89690ae6c6ec8"},
-  "makeup_erlang": {:hex, :makeup_erlang, "0.1.1", "3fcb7f09eb9d98dc4d208f49cc955a34218fc41ff6b84df7c75b3e6e533cc65f", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "174d0809e98a4ef0b3309256cbf97101c6ec01c4ab0b23e926a9e17df2077cbb"},
+  "jason": {:hex, :jason, "1.4.4", "b9226785a9aa77b6857ca22832cffa5d5011a667207eb2a0ad56adb5db443b8a", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "c5eb0cab91f094599f94d55bc63409236a8ec69a21a67814529e8d5f6cc90b3b"},
+  "makeup": {:hex, :makeup, "1.2.1", "e90ac1c65589ef354378def3ba19d401e739ee7ee06fb47f94c687016e3713d1", [:mix], [{:nimble_parsec, "~> 1.4", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "d36484867b0bae0fea568d10131197a4c2e47056a6fbe84922bf6ba71c8d17ce"},
+  "makeup_elixir": {:hex, :makeup_elixir, "1.0.1", "e928a4f984e795e41e3abd27bfc09f51db16ab8ba1aebdba2b3a575437efafc2", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.2.3 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "7284900d412a3e5cfd97fdaed4f5ed389b8f2b4cb49efc0eb3bd10e2febf9507"},
+  "makeup_erlang": {:hex, :makeup_erlang, "1.0.3", "4252d5d4098da7415c390e847c814bad3764c94a814a0b4245176215615e1035", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "953297c02582a33411ac6208f2c6e55f0e870df7f80da724ed613f10e6706afd"},
   "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], [], "hexpm", "69b09adddc4f74a40716ae54d140f93beb0fb8978d8636eaded0c31b6f099f16"},
-  "mimerl": {:hex, :mimerl, "1.2.0", "67e2d3f571088d5cfd3e550c383094b47159f3eee8ffa08e64106cdf5e981be3", [:rebar3], [], "hexpm", "f278585650aa581986264638ebf698f8bb19df297f66ad91b18910dfc6e19323"},
-  "mox": {:hex, :mox, "0.5.2", "55a0a5ba9ccc671518d068c8dddd20eeb436909ea79d1799e2209df7eaa98b6c", [:mix], [], "hexpm", "df4310628cd628ee181df93f50ddfd07be3e5ecc30232d3b6aadf30bdfe6092b"},
-  "nimble_parsec": {:hex, :nimble_parsec, "1.1.0", "3a6fca1550363552e54c216debb6a9e95bd8d32348938e13de5eda962c0d7f89", [:mix], [], "hexpm", "08eb32d66b706e913ff748f11694b17981c0b04a33ef470e33e11b3d3ac8f54b"},
-  "parse_trans": {:hex, :parse_trans, "3.3.1", "16328ab840cc09919bd10dab29e431da3af9e9e7e7e6f0089dd5a2d2820011d8", [:rebar3], [], "hexpm", "07cd9577885f56362d414e8c4c4e6bdf10d43a8767abb92d24cbe8b24c54888b"},
-  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.6", "cf344f5692c82d2cd7554f5ec8fd961548d4fd09e7d22f5b62482e5aeaebd4b0", [:make, :mix, :rebar3], [], "hexpm", "bdb0d2471f453c88ff3908e7686f86f9be327d065cc1ec16fa4540197ea04680"},
-  "sweet_xml": {:hex, :sweet_xml, "0.6.6", "fc3e91ec5dd7c787b6195757fbcf0abc670cee1e4172687b45183032221b66b8", [:mix], [], "hexpm", "2e1ec458f892ffa81f9f8386e3f35a1af6db7a7a37748a64478f13163a1f3573"},
-  "telemetry": {:hex, :telemetry, "0.4.3", "a06428a514bdbc63293cd9a6263aad00ddeb66f608163bdec7c8995784080818", [:rebar3], [], "hexpm", "eb72b8365ffda5bed68a620d1da88525e326cb82a75ee61354fc24b844768041"},
-  "unicode_util_compat": {:hex, :unicode_util_compat, "0.7.0", "bc84380c9ab48177092f43ac89e4dfa2c6d62b40b8bd132b1059ecc7232f9a78", [:rebar3], [], "hexpm", "25eee6d67df61960cf6a794239566599b09e17e668d3700247bc498638152521"},
+  "mime": {:hex, :mime, "2.0.7", "b8d739037be7cd402aee1ba0306edfdef982687ee7e9859bee6198c1e7e2f128", [:mix], [], "hexpm", "6171188e399ee16023ffc5b76ce445eb6d9672e2e241d2df6050f3c771e80ccd"},
+  "mimerl": {:hex, :mimerl, "1.4.0", "3882a5ca67fbbe7117ba8947f27643557adec38fa2307490c4c4207624cb213b", [:rebar3], [], "hexpm", "13af15f9f68c65884ecca3a3891d50a7b57d82152792f3e19d88650aa126b144"},
+  "mox": {:hex, :mox, "1.2.0", "a2cd96b4b80a3883e3100a221e8adc1b98e4c3a332a8fc434c39526babafd5b3", [:mix], [{:nimble_ownership, "~> 1.0", [hex: :nimble_ownership, repo: "hexpm", optional: false]}], "hexpm", "c7b92b3cc69ee24a7eeeaf944cd7be22013c52fcb580c1f33f50845ec821089a"},
+  "nimble_ownership": {:hex, :nimble_ownership, "1.0.2", "fa8a6f2d8c592ad4d79b2ca617473c6aefd5869abfa02563a77682038bf916cf", [:mix], [], "hexpm", "098af64e1f6f8609c6672127cfe9e9590a5d3fcdd82bc17a377b8692fd81a879"},
+  "nimble_parsec": {:hex, :nimble_parsec, "1.4.2", "8efba0122db06df95bfaa78f791344a89352ba04baedd3849593bfce4d0dc1c6", [:mix], [], "hexpm", "4b21398942dda052b403bbe1da991ccd03a053668d147d53fb8c4e0efe09c973"},
+  "parse_trans": {:hex, :parse_trans, "3.4.1", "6e6aa8167cb44cc8f39441d05193be6e6f4e7c2946cb2759f015f8c56b76e5ff", [:rebar3], [], "hexpm", "620a406ce75dada827b82e453c19cf06776be266f5a67cff34e1ef2cbb60e49a"},
+  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.7", "354c321cf377240c7b8716899e182ce4890c5938111a1296add3ec74cf1715df", [:make, :mix, :rebar3], [], "hexpm", "fe4c190e8f37401d30167c8c405eda19469f34577987c76dde613e838bbc67f8"},
+  "sweet_xml": {:hex, :sweet_xml, "0.7.5", "803a563113981aaac202a1dbd39771562d0ad31004ddbfc9b5090bdcd5605277", [:mix], [], "hexpm", "193b28a9b12891cae351d81a0cead165ffe67df1b73fe5866d10629f4faefb12"},
+  "telemetry": {:hex, :telemetry, "1.3.0", "fedebbae410d715cf8e7062c96a1ef32ec22e764197f70cda73d82778d61e7a2", [:rebar3], [], "hexpm", "7015fc8919dbe63764f4b4b87a95b7c0996bd539e0d499be6ec9d7f3875b79e6"},
+  "unicode_util_compat": {:hex, :unicode_util_compat, "0.7.1", "a48703a25c170eedadca83b11e88985af08d35f37c6f664d6dcfb106a97782fc", [:rebar3], [], "hexpm", "b3a917854ce3ae233619744ad1e0102e05673136776fb2fa76234f3e03b23642"},
 }

test/lib/auth_cache/assume_role_credentials_adapter_test.exs

@@ -8,12 +8,61 @@ defmodule ExAws.STS.AuthCache.AssumeRoleCredentialsAdapterTest do
     profile = "default"
     auth = test_loader(profile)
 
-    body = %{
+    body = """
+    <AssumeRoleResponse>
+      <AssumeRoleResult>
+        <Credentials>
+          <AccessKeyId>1</AccessKeyId>
+          <SecretAccessKey>secret</SecretAccessKey>
+          <SessionToken>token</SessionToken>
+        </Credentials>
+      </AssumeRoleResult>
+      <ResponseMetadata><RequestId>req-id</RequestId></ResponseMetadata>
+    </AssumeRoleResponse>
+    """
+
+    ExAws.Request.HttpMock
+    |> expect(:request, fn _method,
+                           _url,
+                           "Action=AssumeRole&DurationSeconds=900&RoleArn=1111111%2Ftest_role&RoleSessionName=test&Version=2011-06-15",
+                           _headers,
+                           _opts ->
+      {:ok, %{status_code: 200, body: body}}
+    end)
+
+    expected = %{
       access_key_id: "1",
       secret_access_key: "secret",
-      session_token: "token"
+      security_token: "token",
+      role_arn: auth.role_arn,
+      role_session_name: auth.role_session_name,
+      source_profile: auth.source_profile
     }
 
+    assert expected ==
+             AssumeRoleCredentialsAdapter.adapt_auth_config(auth, profile, 300, &test_loader/1)
+  end
+
+  test "#adapt_auth_config resolves {:system, env} role_arn" do
+    System.put_env("ROLE_ARN", "1111111/test_role")
+    on_exit(fn -> System.delete_env("ROLE_ARN") end)
+
+    profile = "default"
+    auth = test_loader("system-role")
+
+    body = """
+    <AssumeRoleResponse>
+      <AssumeRoleResult>
+        <Credentials>
+          <AccessKeyId>1</AccessKeyId>
+          <SecretAccessKey>secret</SecretAccessKey>
+          <SessionToken>token</SessionToken>
+        </Credentials>
+      </AssumeRoleResult>
+      <ResponseMetadata><RequestId>req-id</RequestId></ResponseMetadata>
+    </AssumeRoleResponse>
+    """
+
     ExAws.Request.HttpMock
     |> expect(:request, fn _method,
                            _url,
@@ -24,10 +73,10 @@ defmodule ExAws.STS.AuthCache.AssumeRoleCredentialsAdapterTest do
     end)
 
     expected = %{
-      access_key_id: body.access_key_id,
-      secret_access_key: body.secret_access_key,
-      security_token: body.session_token,
-      role_arn: auth.role_arn,
+      access_key_id: "1",
+      secret_access_key: "secret",
+      security_token: "token",
+      role_arn: "1111111/test_role",
       role_session_name: auth.role_session_name,
       source_profile: auth.source_profile
     }
@@ -36,6 +85,14 @@ defmodule ExAws.STS.AuthCache.AssumeRoleCredentialsAdapterTest do
              AssumeRoleCredentialsAdapter.adapt_auth_config(auth, profile, 300, &test_loader/1)
   end
 
+  test "#adapt_auth_config passes through auth when role_arn is missing" do
+    profile = "default"
+    auth = Map.delete(test_loader("default"), :role_arn)
+
+    assert auth ==
+             AssumeRoleCredentialsAdapter.adapt_auth_config(auth, profile, 300, &test_loader/1)
+  end
+
   defp test_loader("default") do
     %{
       source_profile: "source",
@@ -44,6 +101,14 @@ defmodule ExAws.STS.AuthCache.AssumeRoleCredentialsAdapterTest do
     }
   end
 
+  defp test_loader("system-role") do
+    %{
+      source_profile: "source",
+      role_arn: {:system, "ROLE_ARN"},
+      role_session_name: "test"
+    }
+  end
+
   defp test_loader("source") do
     %{
       http_client: ExAws.Request.HttpMock,

test/lib/auth_cache/assume_role_web_identity_adapter_test.exs

@@ -35,11 +35,18 @@ defmodule ExAws.STS.AuthCache.AssumeRoleWebIdentityAdapterTest do
         http_client: ExAws.Request.HttpMock
       }
 
-      body = %{
-        access_key_id: "1",
-        secret_access_key: "secret",
-        session_token: "token"
-      }
+      body = """
+      <AssumeRoleWithWebIdentityResponse>
+        <AssumeRoleWithWebIdentityResult>
+          <Credentials>
+            <AccessKeyId>1</AccessKeyId>
+            <SecretAccessKey>secret</SecretAccessKey>
+            <SessionToken>token</SessionToken>
+          </Credentials>
+        </AssumeRoleWithWebIdentityResult>
+        <ResponseMetadata><RequestId>req-id</RequestId></ResponseMetadata>
+      </AssumeRoleWithWebIdentityResponse>
+      """
 
       ExAws.Request.HttpMock
       |> expect(:request, fn _method,
@@ -51,9 +58,9 @@ defmodule ExAws.STS.AuthCache.AssumeRoleWebIdentityAdapterTest do
       end)
 
       expected = %{
-        access_key_id: body.access_key_id,
-        secret_access_key: body.secret_access_key,
-        security_token: body.session_token,
+        access_key_id: "1",
+        secret_access_key: "secret",
+        security_token: "token",
         role_arn: config.role_arn,
         role_session_name: config.role_session_name,
         expiration: expiration
@@ -75,11 +82,18 @@ defmodule ExAws.STS.AuthCache.AssumeRoleWebIdentityAdapterTest do
         http_client: ExAws.Request.HttpMock
       }
 
-      body = %{
-        access_key_id: "1",
-        secret_access_key: "secret",
-        session_token: "token"
-      }
+      body = """
+      <AssumeRoleWithWebIdentityResponse>
+        <AssumeRoleWithWebIdentityResult>
+          <Credentials>
+            <AccessKeyId>1</AccessKeyId>
+            <SecretAccessKey>secret</SecretAccessKey>
+            <SessionToken>token</SessionToken>
+          </Credentials>
+        </AssumeRoleWithWebIdentityResult>
+        <ResponseMetadata><RequestId>req-id</RequestId></ResponseMetadata>
+      </AssumeRoleWithWebIdentityResponse>
+      """
 
       ExAws.Request.HttpMock
       |> expect(:request, fn _method,
@@ -91,9 +105,9 @@ defmodule ExAws.STS.AuthCache.AssumeRoleWebIdentityAdapterTest do
       end)
 
       expected = %{
-        access_key_id: body.access_key_id,
-        secret_access_key: body.secret_access_key,
-        security_token: body.session_token,
+        access_key_id: "1",
+        secret_access_key: "secret",
+        security_token: "token",
         role_arn: @role_arn,
         role_session_name: @role_session_name,
         expiration: @expiration