create model references with dynamic config

go/genkit/model.go

@@ -0,0 +1,81 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package genkit
+
+type ModelStage int
+
+/** At which stage of development the model is.
+ * - `featured` models are recommended for general use.
+ * - `stable` models are well-tested and reliable.
+ * - `unstable` models are experimental and may change.
+ * - `legacy` models are no longer recommended for new projects.
+ * - `deprecated` models are deprecated by the provider and may be removed in future versions.
+ */
+const (
+	FEATURED ModelStage = iota
+	STABLE
+	UNSTABLE
+	LEGACY
+	DEPRECATED
+)
+
+type ModelCapabilities struct {
+	/** Model can output this type of data. */
+	Output []string
+	/** Model supports output in these content types. */
+	ContentType []string
+	/** Model can process historical messages passed with a prompt. */
+	Multiturn bool
+	/** Model can process media as part of the prompt (multimodal input). */
+	Media bool
+	/** Model can perform tool calls. */
+	Tools bool
+	/** Model can accept messages with role "system". */
+	SystemRole bool
+	/** Model can natively support document-based context grounding. */
+	Context bool
+}
+
+type ModelInfo struct {
+	Versions []string
+	Label    string
+	Supports ModelCapabilities
+	// TODO: is Stage needed?
+	Stage ModelStage
+}
+
+type ModelReference struct {
+	Name    string
+	Version string
+	Info    ModelInfo
+	// TODO: configSchema and config should be something
+}
+
+type WithConfig func(*ModelReference)
+
+func WithVersion(version string) WithConfig {
+	return func(m *ModelReference) {
+		m.Version = version
+	}
+}
+
+func ModelRef(opts ...WithConfig) *ModelReference {
+	m := &ModelReference{}
+	for _, opt := range opts {
+		opt(m)
+	}
+
+	return m
+}