feat: support for list in inputs

Signed-off-by: Dmitri Khokhlov <dkhokhlov@gmail.com>

pkg/predict/input.go

@@ -1,20 +1,22 @@
 package predict
 
 import (
+	"encoding/json"
+	"fmt"
+	"github.com/vincent-petithory/dataurl"
+	"mime"
 	"os"
 	"path/filepath"
 	"strings"
 
 	"github.com/mitchellh/go-homedir"
-	"github.com/vincent-petithory/dataurl"
-
 	"github.com/replicate/cog/pkg/util/console"
-	"github.com/replicate/cog/pkg/util/mime"
 )
 
 type Input struct {
 	String *string
 	File   *string
+	Array  *[]interface{}
 }
 
 type Inputs map[string]Input
@@ -25,15 +27,16 @@ func NewInputs(keyVals map[string]string) Inputs {
 		val := val
 		if strings.HasPrefix(val, "@") {
 			val = val[1:]
-			expandedVal, err := homedir.Expand(val)
-			if err != nil {
-				// FIXME: handle this better?
-				console.Warnf("Error expanding homedir: %s", err)
+			input[key] = Input{File: &val}
+		} else if strings.HasPrefix(val, "[") && strings.HasSuffix(val, "]") {
+			// Handle array of strings
+			var arr []interface{}
+			if err := json.Unmarshal([]byte(val), &arr); err != nil {
+				// Handle JSON unmarshalling error
+				console.Warnf("Error parsing array for key '%s': %s", key, err)
 			} else {
-				val = expandedVal
+				input[key] = Input{Array: &arr}
 			}
-
-			input[key] = Input{File: &val}
 		} else {
 			input[key] = Input{String: &val}
 		}
@@ -55,19 +58,54 @@ func NewInputsWithBaseDir(keyVals map[string]string, baseDir string) Inputs {
 	return input
 }
 
-func (inputs *Inputs) toMap() (map[string]string, error) {
-	keyVals := map[string]string{}
+func (inputs *Inputs) toMap() (map[string]interface{}, error) {
+	keyVals := map[string]interface{}{}
 	for key, input := range *inputs {
 		if input.String != nil {
+			// Directly assign the string value
 			keyVals[key] = *input.String
 		} else if input.File != nil {
-			content, err := os.ReadFile(*input.File)
+			// Single file handling: read content and convert to a data URL
+			dataURL, err := fileToDataURL(*input.File)
 			if err != nil {
 				return keyVals, err
 			}
-			mimeType := mime.TypeByExtension(filepath.Ext(*input.File))
-			keyVals[key] = dataurl.New(content, mimeType).String()
+			keyVals[key] = dataURL
+		} else if input.Array != nil {
+			// Handle array, potentially containing file paths
+			var dataURLs []string
+			for _, elem := range *input.Array {
+				if str, ok := elem.(string); ok && strings.HasPrefix(str, "@") {
+					filePath := str[1:] // Remove '@' prefix
+					dataURL, err := fileToDataURL(filePath)
+					if err != nil {
+						return keyVals, err
+					}
+					dataURLs = append(dataURLs, dataURL)
+				} else if ok {
+					// Directly use the string if it's not a file path
+					dataURLs = append(dataURLs, str)
+				}
+			}
+			keyVals[key] = dataURLs
 		}
 	}
 	return keyVals, nil
 }
+
+// Helper function to read file content and convert to a data URL
+func fileToDataURL(filePath string) (string, error) {
+	// Expand home directory if necessary
+	expandedVal, err := homedir.Expand(filePath)
+	if err != nil {
+		return "", fmt.Errorf("error expanding homedir for '%s': %w", filePath, err)
+	}
+
+	content, err := os.ReadFile(expandedVal)
+	if err != nil {
+		return "", err
+	}
+	mimeType := mime.TypeByExtension(filepath.Ext(expandedVal))
+	dataURL := dataurl.New(content, mimeType).String()
+	return dataURL, nil
+}

pkg/predict/predictor.go

@@ -24,7 +24,7 @@ type HealthcheckResponse struct {
 
 type Request struct {
 	// TODO: could this be Inputs?
-	Input map[string]string `json:"input"`
+	Input map[string]interface{} `json:"input"`
 }
 
 type Response struct {