Rework integration test setup and auth

[AlekSi]

What should be done?

At the moment, we fetch flag values but each test can't assign value for the flag. Additionally -handler flag is used incorrectly for validator.

• Validators should be used only for target. When we run compatibility tests with target=tigris and compat=MongoDB, we get validators for tigris handler for both databases and then ignore MongoDB's error. In general, -handler's flag value is used incorrectly.

  FerretDB/integration/setup/setup_compat.go

  Line 131 in f0ca781

  func setupCompatCollections(tb testing.TB, ctx context.Context, client *mongo.Client, opts *SetupCompatOpts) []*mongo.Collection {

• Integration setup uses flag's value but unable to specify flags used per test cases. Enable test cases to test authentication.

  FerretDB/integration/setup/common.go

  Line 231 in f0ca781

  PostgreSQLURL: *postgreSQLURLF,

• Test different flags values of env data TestEnvData.
• Test different flag values of postgresql-url in TestCommandsAuthenticationSASLStart
• Provider is compatible with both compat and target, but validator is only compatible with target. Fix this definition

  FerretDB/integration/shareddata/shareddata.go

  Lines 33 to 39 in 62039bf

  	// Handlers returns handlers compatible with this provider.
  	Handlers() []string
  	// Validators returns validators for the given handler and collection.
  	// For example, for Tigris it should return a map with they key $tigrisSchemaString
  	// and the value containing Tigris' JSON schema string.
  	Validators(handler, collection string) map[string]any

• pg uri used for testing is set from creating a new listener or using existing connection on port. Rework on how uri is built and used. Currently attempting all possible combinations. Probably this wouldn't help for speed.

  FerretDB/integration/setup/common.go

  Lines 170 to 181 in cc7b47d

  	for _, c := range []struct {
  	user *url.Userinfo
  	authMechanism string
  	}{{
  	user: nil,
  	authMechanism: "",
  	}, {
  	user: url.UserPassword("username", "password"),
  	authMechanism: "PLAIN",
  	}, {
  	user: url.UserPassword("username", "password"),
  	authMechanism: "", // defaults to SCRAM when username is set

• Remove code like

  FerretDB/integration/create_test.go

  Lines 70 to 81 in 56a2dd1

  	// Attempt to create a collection for Tigris with a schema.
  	// If we get an error that support for "validator" is not implemented, that's Postgres.
  	// If we get an error that "$tigrisSchemaString" is unknown, that's MongoDB.
  	// In both cases, we create a collection without a schema.
  	err := db.CreateCollection(ctx, collName, &opts)
  	if err != nil {
  	if errorTextContains(err,
  	`support for field "validator" is not implemented yet`,
  	`unknown top level operator: $tigrisSchemaString`,
  	) {
  	err = db.CreateCollection(ctx, collName)
  	}

Keep note that maybe we may want test data per provider.

Where?

See references to this issue in code.

DoD:

• in compat test, validators are correctly applied for target but not for compat.
• tests added for TestCommandsAuthenticationSASLStart
  • authentication with PLAIN
  • authentication with invalid credential
  • authentication with valid credential
• uri for specific target/compat is being built.
• validator is not used for compat
• address issue numbers mentioned in the code

---

• rework validations in shareddata
• fix task env-data (Fix env-data Taskfile target #2200)
• fix test script

[AlekSi]

I will check what else we could do

[AlekSi]

I will check if we could do something more useful