webhooker/internal/config/sentry_test.go

package config_test

import (
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"sneak.berlin/go/webhooker/internal/config"
)

// envKeySentryDSN is the variable envSentryDSN reads in production.
const envKeySentryDSN = "SENTRY_DSN"

// validSentryDSN is a syntactically complete DSN. The host is under
// .invalid (RFC 2606), so nothing a test builds around it can reach a
// real Sentry installation.
const validSentryDSN = "https://abc123@sentry.invalid/42"

// envSentryDSNCase is one row of the envSentryDSN table.
type envSentryDSNCase struct {
	name        string
	set         bool
	value       string
	expectError bool
	expected    string
}

// envSentryDSNCases is the envSentryDSN table. The three invalid
// values are the ones measured on the defect: each initialised the SDK
// with an error and left the process serving with reporting off.
func envSentryDSNCases() []envSentryDSNCase {
	return []envSentryDSNCase{
		{
			name:     "unset means reporting off",
			expected: "",
		},
		{
			name:     "empty means reporting off",
			set:      true,
			value:    "",
			expected: "",
		},
		{
			name:     "whitespace means reporting off",
			set:      true,
			value:    "   ",
			expected: "",
		},
		{
			name:     "a valid DSN is kept",
			set:      true,
			value:    validSentryDSN,
			expected: validSentryDSN,
		},
		{
			name:     "surrounding whitespace is trimmed",
			set:      true,
			value:    "  " + validSentryDSN + "\t",
			expected: validSentryDSN,
		},
		{
			name:        "a value that is not a URL is rejected",
			set:         true,
			value:       "not-a-dsn",
			expectError: true,
		},
		{
			name:        "an unparseable URL is rejected",
			set:         true,
			value:       "%%%",
			expectError: true,
		},
		{
			name:        "a DSN without a public key is rejected",
			set:         true,
			value:       "https://example.invalid/1",
			expectError: true,
		},
		{
			name:        "a DSN without a project id is rejected",
			set:         true,
			value:       "https://abc123@sentry.invalid/",
			expectError: true,
		},
		{
			name:        "a non-HTTP scheme is rejected",
			set:         true,
			value:       "ftp://abc123@sentry.invalid/42",
			expectError: true,
		},
	}
}

// TestEnvSentryDSN covers the helper directly. What it pins beyond the
// value is the failure shape: a set-but-unparseable DSN names the
// variable and the value, exactly as the other fail-loud helpers do,
// so an operator reads the fix off the message.
func TestEnvSentryDSN(t *testing.T) {
	for _, tt := range envSentryDSNCases() {
		t.Run(tt.name, func(t *testing.T) {
			// Cannot use t.Parallel() here because t.Setenv
			// is incompatible with parallel subtests.
			config.ClearEnvForTest(t)

			if tt.set {
				t.Setenv(envKeySentryDSN, tt.value)
			}

			got, err := config.EnvSentryDSNForTest(envKeySentryDSN)

			if tt.expectError {
				require.Error(t, err)
				require.ErrorIs(t, err, config.ErrInvalidSentryDSN)
				assert.Contains(t, err.Error(), envKeySentryDSN)
				assert.Contains(t, err.Error(), tt.value)
				assert.Empty(t, got)

				return
			}

			require.NoError(t, err)
			assert.Equal(t, tt.expected, got)
		})
	}
}

// TestSentryEnabled_TracksTheDSN pins that the one method answering
// "is anything being reported" agrees with the DSN in every state. The
// startup log, the SDK initialisation and the sentryhttp middleware
// all read it, so a log field cannot report reporting as on while
// nothing is sending.
func TestSentryEnabled_TracksTheDSN(t *testing.T) {
	t.Parallel()

	assert.False(t, (&config.Config{}).SentryEnabled())
	assert.True(
		t,
		(&config.Config{SentryDSN: validSentryDSN}).SentryEnabled(),
	)
}