feat: support OpenRouter image generation endpoint

relay/channel/openai/adaptor.go

@@ -163,6 +163,14 @@ func (a *Adaptor) GetRequestURL(info *relaycommon.RelayInfo) (string, error) {
 		url := info.ChannelBaseUrl
 		url = strings.Replace(url, "{model}", info.UpstreamModelName, -1)
 		return url, nil
+	case constant.ChannelTypeOpenRouter:
+		// OpenRouter's image generation endpoint is POST {base}/v1/images
+		// (https://openrouter.ai/docs/features/multimodal/image-generation-api),
+		// not the OpenAI-style /v1/images/generations.
+		if info.RelayMode == relayconstant.RelayModeImagesGenerations {
+			return fmt.Sprintf("%s/v1/images", info.ChannelBaseUrl), nil
+		}
+		fallthrough
 	default:
 		if (info.RelayFormat == types.RelayFormatClaude || info.RelayFormat == types.RelayFormatGemini) &&
 			info.RelayMode != relayconstant.RelayModeResponses &&
@@ -556,6 +564,12 @@ func (a *Adaptor) ConvertImageRequest(c *gin.Context, info *relaycommon.RelayInf
 		return &requestBody, nil
 
 	default:
+		// OpenRouter's /v1/images endpoint accepts params outside the OpenAI
+		// image schema, so merge the unknown fields captured in Extra back
+		// into the outbound body for this channel only.
+		if info.ChannelType == constant.ChannelTypeOpenRouter && info.RelayMode == relayconstant.RelayModeImagesGenerations {
+			return mergeImageRequestExtra(request)
+		}
 		return request, nil
 	}
 }

relay/channel/openai/openrouter_image.go

@@ -0,0 +1,31 @@
+package openai
+
+import (
+	"encoding/json"
+
+	"github.com/QuantumNous/new-api/common"
+	"github.com/QuantumNous/new-api/dto"
+)
+
+// mergeImageRequestExtra flattens the unknown fields captured in
+// ImageRequest.Extra back into the outbound JSON body. OpenRouter's
+// /v1/images endpoint accepts params outside the OpenAI image schema
+// (aspect_ratio, resolution, seed, input_references, provider), which
+// the generic ImageRequest serialization drops. Known fields always
+// win over Extra entries with the same key.
+func mergeImageRequestExtra(request dto.ImageRequest) (map[string]json.RawMessage, error) {
+	base, err := common.Marshal(request)
+	if err != nil {
+		return nil, err
+	}
+	var bodyMap map[string]json.RawMessage
+	if err := common.Unmarshal(base, &bodyMap); err != nil {
+		return nil, err
+	}
+	for k, v := range request.Extra {
+		if _, exists := bodyMap[k]; !exists {
+			bodyMap[k] = v
+		}
+	}
+	return bodyMap, nil
+}

relay/channel/openai/openrouter_image_test.go

@@ -0,0 +1,140 @@
+package openai
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/QuantumNous/new-api/common"
+	"github.com/QuantumNous/new-api/constant"
+	"github.com/QuantumNous/new-api/dto"
+	relaycommon "github.com/QuantumNous/new-api/relay/common"
+	relayconstant "github.com/QuantumNous/new-api/relay/constant"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TestGetRequestURLOpenRouterImageGeneration verifies that image generation
+// requests to an OpenRouter channel are sent to OpenRouter's flat
+// {base}/v1/images endpoint instead of the OpenAI-style /v1/images/generations.
+func TestGetRequestURLOpenRouterImageGeneration(t *testing.T) {
+	t.Parallel()
+
+	adaptor := &Adaptor{}
+	info := &relaycommon.RelayInfo{
+		RelayMode:      relayconstant.RelayModeImagesGenerations,
+		RequestURLPath: "/v1/images/generations",
+		ChannelMeta: &relaycommon.ChannelMeta{
+			ChannelType:    constant.ChannelTypeOpenRouter,
+			ChannelBaseUrl: "https://openrouter.ai/api",
+		},
+	}
+
+	got, err := adaptor.GetRequestURL(info)
+	require.NoError(t, err)
+	assert.Equal(t, "https://openrouter.ai/api/v1/images", got)
+}
+
+// TestGetRequestURLOpenRouterChatUnchanged guards against the image special
+// case leaking into the chat completions path for OpenRouter channels.
+func TestGetRequestURLOpenRouterChatUnchanged(t *testing.T) {
+	t.Parallel()
+
+	adaptor := &Adaptor{}
+	info := &relaycommon.RelayInfo{
+		RelayMode:      relayconstant.RelayModeChatCompletions,
+		RequestURLPath: "/v1/chat/completions",
+		ChannelMeta: &relaycommon.ChannelMeta{
+			ChannelType:    constant.ChannelTypeOpenRouter,
+			ChannelBaseUrl: "https://openrouter.ai/api",
+		},
+	}
+
+	got, err := adaptor.GetRequestURL(info)
+	require.NoError(t, err)
+	assert.Equal(t, "https://openrouter.ai/api/v1/chat/completions", got)
+}
+
+// TestConvertImageRequestOpenRouterMergesExtra verifies that OpenRouter-specific
+// image generation params captured in ImageRequest.Extra (aspect_ratio, seed,
+// provider, ...) are merged back into the outbound body for OpenRouter channels,
+// alongside the known OpenAI fields.
+func TestConvertImageRequestOpenRouterMergesExtra(t *testing.T) {
+	t.Parallel()
+
+	body := `{
+		"model": "google/gemini-2.5-flash-image",
+		"prompt": "a cat wearing a hat",
+		"aspect_ratio": "16:9",
+		"seed": 42,
+		"provider": {"options": {"only": ["google-vertex"]}}
+	}`
+	var request dto.ImageRequest
+	require.NoError(t, common.Unmarshal([]byte(body), &request))
+	require.Contains(t, request.Extra, "aspect_ratio")
+
+	adaptor := &Adaptor{}
+	info := &relaycommon.RelayInfo{
+		RelayMode:      relayconstant.RelayModeImagesGenerations,
+		RequestURLPath: "/v1/images/generations",
+		ChannelMeta: &relaycommon.ChannelMeta{
+			ChannelType:    constant.ChannelTypeOpenRouter,
+			ChannelBaseUrl: "https://openrouter.ai/api",
+		},
+	}
+
+	converted, err := adaptor.ConvertImageRequest(nil, info, request)
+	require.NoError(t, err)
+
+	serialized, err := common.Marshal(converted)
+	require.NoError(t, err)
+
+	var got map[string]json.RawMessage
+	require.NoError(t, common.Unmarshal(serialized, &got))
+
+	assert.JSONEq(t, `"google/gemini-2.5-flash-image"`, string(got["model"]))
+	assert.JSONEq(t, `"a cat wearing a hat"`, string(got["prompt"]))
+	assert.JSONEq(t, `"16:9"`, string(got["aspect_ratio"]))
+	assert.JSONEq(t, `42`, string(got["seed"]))
+	assert.JSONEq(t, `{"options": {"only": ["google-vertex"]}}`, string(got["provider"]))
+}
+
+// TestConvertImageRequestNonOpenRouterDropsExtra guards the owner's constraint
+// that Extra must NOT be merged globally: for non-OpenRouter channels the
+// serialized body keeps dropping unknown fields.
+func TestConvertImageRequestNonOpenRouterDropsExtra(t *testing.T) {
+	t.Parallel()
+
+	body := `{
+		"model": "gpt-image-1",
+		"prompt": "a cat wearing a hat",
+		"aspect_ratio": "16:9",
+		"seed": 42
+	}`
+	var request dto.ImageRequest
+	require.NoError(t, common.Unmarshal([]byte(body), &request))
+	require.Contains(t, request.Extra, "aspect_ratio")
+
+	adaptor := &Adaptor{}
+	info := &relaycommon.RelayInfo{
+		RelayMode:      relayconstant.RelayModeImagesGenerations,
+		RequestURLPath: "/v1/images/generations",
+		ChannelMeta: &relaycommon.ChannelMeta{
+			ChannelType:    constant.ChannelTypeOpenAI,
+			ChannelBaseUrl: "https://api.openai.com",
+		},
+	}
+
+	converted, err := adaptor.ConvertImageRequest(nil, info, request)
+	require.NoError(t, err)
+
+	serialized, err := common.Marshal(converted)
+	require.NoError(t, err)
+
+	var got map[string]json.RawMessage
+	require.NoError(t, common.Unmarshal(serialized, &got))
+
+	assert.NotContains(t, got, "aspect_ratio")
+	assert.NotContains(t, got, "seed")
+	assert.JSONEq(t, `"gpt-image-1"`, string(got["model"]))
+	assert.JSONEq(t, `"a cat wearing a hat"`, string(got["prompt"]))
+}