Move the client tests into a test package

This work has been extracted from testcontainers#2202 and is related to testcontainers#2180. See the original PR for the full context and reasoning.

This will help with the documentation, since all examples will now have the module prefixes.

docker_auth_config_test.go

@@ -0,0 +1,158 @@
+// This test is testing very internal logic that should not be exported away from this package. We'll
+// leave it in the main testcontainers package. Do not use for user facing examples.
+package testcontainers
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+
+	"github.com/cpuguy83/dockercfg"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/testcontainers/testcontainers-go/internal/core"
+)
+
+const exampleAuth = "https://example-auth.com"
+
+var testDockerConfigDirPath = filepath.Join("testdata", ".docker")
+
+var indexDockerIO = core.IndexDockerIO
+
+func TestGetDockerConfig(t *testing.T) {
+	const expectedErrorMessage = "Expected to find %s in auth configs"
+
+	// Verify that the default docker config file exists before any test in this suite runs.
+	// Then, we can safely run the tests that rely on it.
+	defaultCfg, err := dockercfg.LoadDefaultConfig()
+	require.NoError(t, err)
+	require.NotEmpty(t, defaultCfg)
+
+	t.Run("without DOCKER_CONFIG env var retrieves default", func(t *testing.T) {
+		t.Setenv("DOCKER_CONFIG", "")
+
+		cfg, err := getDockerConfig()
+		require.NoError(t, err)
+		require.NotEmpty(t, cfg)
+
+		assert.Equal(t, defaultCfg, cfg)
+	})
+
+	t.Run("with DOCKER_CONFIG env var pointing to a non-existing file raises error", func(t *testing.T) {
+		t.Setenv("DOCKER_CONFIG", filepath.Join(testDockerConfigDirPath, "non-existing"))
+
+		cfg, err := getDockerConfig()
+		require.Error(t, err)
+		require.Empty(t, cfg)
+	})
+
+	t.Run("with DOCKER_CONFIG env var", func(t *testing.T) {
+		t.Setenv("DOCKER_CONFIG", testDockerConfigDirPath)
+
+		cfg, err := getDockerConfig()
+		require.NoError(t, err)
+		require.NotEmpty(t, cfg)
+
+		assert.Len(t, cfg.AuthConfigs, 3)
+
+		authCfgs := cfg.AuthConfigs
+
+		if _, ok := authCfgs[indexDockerIO]; !ok {
+			t.Errorf(expectedErrorMessage, indexDockerIO)
+		}
+		if _, ok := authCfgs["https://example.com"]; !ok {
+			t.Errorf(expectedErrorMessage, "https://example.com")
+		}
+		if _, ok := authCfgs["https://my.private.registry"]; !ok {
+			t.Errorf(expectedErrorMessage, "https://my.private.registry")
+		}
+	})
+
+	t.Run("DOCKER_AUTH_CONFIG env var takes precedence", func(t *testing.T) {
+		t.Setenv("DOCKER_AUTH_CONFIG", `{
+			"auths": {
+					"`+exampleAuth+`": {}
+			},
+			"credsStore": "desktop"
+		}`)
+		t.Setenv("DOCKER_CONFIG", testDockerConfigDirPath)
+
+		cfg, err := getDockerConfig()
+		require.NoError(t, err)
+		require.NotEmpty(t, cfg)
+
+		assert.Len(t, cfg.AuthConfigs, 1)
+
+		authCfgs := cfg.AuthConfigs
+
+		if _, ok := authCfgs[indexDockerIO]; ok {
+			t.Errorf("Not expected to find %s in auth configs", indexDockerIO)
+		}
+		if _, ok := authCfgs[exampleAuth]; !ok {
+			t.Errorf(expectedErrorMessage, exampleAuth)
+		}
+	})
+
+	t.Run("retrieve auth with DOCKER_AUTH_CONFIG env var", func(t *testing.T) {
+		base64 := "Z29waGVyOnNlY3JldA==" // gopher:secret
+
+		t.Setenv("DOCKER_AUTH_CONFIG", `{
+			"auths": {
+					"`+exampleAuth+`": { "username": "gopher", "password": "secret", "auth": "`+base64+`" }
+			},
+			"credsStore": "desktop"
+		}`)
+
+		registry, cfg, err := DockerImageAuth(context.Background(), exampleAuth+"/my/image:latest")
+		require.NoError(t, err)
+		require.NotEmpty(t, cfg)
+
+		assert.Equal(t, exampleAuth, registry)
+		assert.Equal(t, "gopher", cfg.Username)
+		assert.Equal(t, "secret", cfg.Password)
+		assert.Equal(t, base64, cfg.Auth)
+	})
+
+	t.Run("match registry authentication by host", func(t *testing.T) {
+		base64 := "Z29waGVyOnNlY3JldA==" // gopher:secret
+		imageReg := "example-auth.com"
+		imagePath := "/my/image:latest"
+
+		t.Setenv("DOCKER_AUTH_CONFIG", `{
+			"auths": {
+					"`+exampleAuth+`": { "username": "gopher", "password": "secret", "auth": "`+base64+`" }
+			},
+			"credsStore": "desktop"
+		}`)
+
+		registry, cfg, err := DockerImageAuth(context.Background(), imageReg+imagePath)
+		require.NoError(t, err)
+		require.NotEmpty(t, cfg)
+
+		assert.Equal(t, imageReg, registry)
+		assert.Equal(t, "gopher", cfg.Username)
+		assert.Equal(t, "secret", cfg.Password)
+		assert.Equal(t, base64, cfg.Auth)
+	})
+
+	t.Run("fail to match registry authentication due to invalid host", func(t *testing.T) {
+		base64 := "Z29waGVyOnNlY3JldA==" // gopher:secret
+		imageReg := "example-auth.com"
+		imagePath := "/my/image:latest"
+		invalidRegistryURL := "://invalid-host"
+
+		t.Setenv("DOCKER_AUTH_CONFIG", `{
+			"auths": {
+					"`+invalidRegistryURL+`": { "username": "gopher", "password": "secret", "auth": "`+base64+`" }
+			},
+			"credsStore": "desktop"
+		}`)
+
+		registry, cfg, err := DockerImageAuth(context.Background(), imageReg+imagePath)
+		require.Equal(t, err, dockercfg.ErrCredentialsNotFound)
+		require.Empty(t, cfg)
+
+		assert.Equal(t, imageReg, registry)
+	})
+}