Custom HTTP request to list openrouter models, so pricing information…

… can be extracted from the API response

Part of #210

provider/openrouter/openrouter.go

@@ -2,7 +2,10 @@ package openrouter
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
+	"io"
+	"net/http"
 	"strings"
 	"time"
 
@@ -51,18 +54,72 @@ func (p *Provider) ID() (id string) {
 	return "openrouter"
 }
 
+// ModelsList holds a list of models.
+type ModelsList struct {
+	Models []Model `json:"data"`
+}
+
+// Model holds a model.
+type Model struct {
+	// ID holds the model id.
+	ID string `json:"id"`
+	// Pricing holds the pricing information of a model.
+	Pricing Pricing `json:"pricing"`
+}
+
+// Pricing holds the pricing information of a model.
+type Pricing struct {
+	// Prompt holds the price for a prompt in dollars per token.
+	Prompt string `json:"prompt"`
+	// Completion holds the price for a completion in dollars per token.
+	Completion string `json:"completion"`
+	// Request holds the price for a request in dollars per request.
+	Request string `json:"request"`
+	// Image holds the price for an image in dollars per token.
+	Image string `json:"image"`
+}
+
 // Models returns which models are available to be queried via this provider.
 func (p *Provider) Models() (models []model.Model, err error) {
-	client := p.client()
+	responseModels, err := providerModels(p.baseURL + "/models")
+	if err != nil {
+		return nil, err
+	}
 
-	var responseModels openai.ModelsList
+	models = make([]model.Model, len(responseModels.Models))
+	for i, model := range responseModels.Models {
+		models[i] = llm.NewModel(p, p.ID()+provider.ProviderModelSeparator+model.ID)
+	}
+
+	return models, nil
+}
+
+// providerModels returns the provider's list of models given the URL to fetch the models.
+func providerModels(url string) (models ModelsList, err error) {
+	request, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return ModelsList{}, pkgerrors.WithStack(err)
+	}
+	request.Header.Set("Accept", "application/json")
+
+	client := &http.Client{}
+	var responseBody []byte
 	if err := retry.Do( // Query available models with a retry logic cause "openrouter.ai" has failed us in the past.
 		func() error {
-			ms, err := client.ListModels(context.Background())
+			response, err := client.Do(request)
+			if err != nil {
+				return pkgerrors.WithStack(err)
+			}
+			defer response.Body.Close()
+
+			if response.StatusCode != http.StatusOK {
+				return pkgerrors.Errorf("received status code %d when querying provider models", response.StatusCode)
+			}
+
+			responseBody, err = io.ReadAll(response.Body)
 			if err != nil {
 				return pkgerrors.WithStack(err)
 			}
-			responseModels = ms
 
 			return nil
 		},
@@ -71,12 +128,11 @@ func (p *Provider) Models() (models []model.Model, err error) {
 		retry.DelayType(retry.BackOffDelay),
 		retry.LastErrorOnly(true),
 	); err != nil {
-		return nil, err
+		return ModelsList{}, err
 	}
 
-	models = make([]model.Model, len(responseModels.Models))
-	for i, model := range responseModels.Models {
-		models[i] = llm.NewModel(p, p.ID()+provider.ProviderModelSeparator+model.ID)
+	if err = json.Unmarshal(responseBody, &models); err != nil {
+		return ModelsList{}, pkgerrors.WithStack(err)
 	}
 
 	return models, nil