Introduce Groups Feature (#107)

Groups allows more control over swapping behaviour when a model is requested. The new groups feature provides three ways to control swapping: within the group, swapping out other groups or keep the models in the group loaded persistently (never swapped out). 

Closes #96, #99 and #106.

proxy/config.go

@@ -3,12 +3,15 @@ package proxy
 import (
 	"fmt"
 	"os"
+	"sort"
 	"strings"
 
 	"github.com/google/shlex"
 	"gopkg.in/yaml.v3"
 )
 
+const DEFAULT_GROUP_ID = "(default)"
+
 type ModelConfig struct {
 	Cmd           string   `yaml:"cmd"`
 	Proxy         string   `yaml:"proxy"`
@@ -24,12 +27,38 @@ func (m *ModelConfig) SanitizedCommand() ([]string, error) {
 	return SanitizeCommand(m.Cmd)
 }
 
+type GroupConfig struct {
+	Swap       bool     `yaml:"swap"`
+	Exclusive  bool     `yaml:"exclusive"`
+	Persistent bool     `yaml:"persistent"`
+	Members    []string `yaml:"members"`
+}
+
+// set default values for GroupConfig
+func (c *GroupConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type rawGroupConfig GroupConfig
+	defaults := rawGroupConfig{
+		Swap:       true,
+		Exclusive:  true,
+		Persistent: false,
+		Members:    []string{},
+	}
+
+	if err := unmarshal(&defaults); err != nil {
+		return err
+	}
+
+	*c = GroupConfig(defaults)
+	return nil
+}
+
 type Config struct {
 	HealthCheckTimeout int                    `yaml:"healthCheckTimeout"`
 	LogRequests        bool                   `yaml:"logRequests"`
 	LogLevel           string                 `yaml:"logLevel"`
-	Models             map[string]ModelConfig `yaml:"models"`
+	Models             map[string]ModelConfig `yaml:"models"` /* key is model ID */
 	Profiles           map[string][]string    `yaml:"profiles"`
+	Groups             map[string]GroupConfig `yaml:"groups"` /* key is group ID */
 
 	// map aliases to actual model IDs
 	aliases map[string]string
@@ -53,16 +82,16 @@ func (c *Config) FindConfig(modelName string) (ModelConfig, string, bool) {
 	}
 }
 
-func LoadConfig(path string) (*Config, error) {
+func LoadConfig(path string) (Config, error) {
 	data, err := os.ReadFile(path)
 	if err != nil {
-		return nil, err
+		return Config{}, err
 	}
 
 	var config Config
 	err = yaml.Unmarshal(data, &config)
 	if err != nil {
-		return nil, err
+		return Config{}, err
 	}
 
 	if config.HealthCheckTimeout < 15 {
@@ -77,7 +106,72 @@ func LoadConfig(path string) (*Config, error) {
 		}
 	}
 
-	return &config, nil
+	config = AddDefaultGroupToConfig(config)
+	// check that members are all unique in the groups
+	memberUsage := make(map[string]string) // maps member to group it appears in
+	for groupID, groupConfig := range config.Groups {
+		prevSet := make(map[string]bool)
+		for _, member := range groupConfig.Members {
+			// Check for duplicates within this group
+			if _, found := prevSet[member]; found {
+				return Config{}, fmt.Errorf("duplicate model member %s found in group: %s", member, groupID)
+			}
+			prevSet[member] = true
+
+			// Check if member is used in another group
+			if existingGroup, exists := memberUsage[member]; exists {
+				return Config{}, fmt.Errorf("model member %s is used in multiple groups: %s and %s", member, existingGroup, groupID)
+			}
+			memberUsage[member] = groupID
+		}
+	}
+
+	return config, nil
+}
+
+// rewrites the yaml to include a default group with any orphaned models
+func AddDefaultGroupToConfig(config Config) Config {
+
+	if config.Groups == nil {
+		config.Groups = make(map[string]GroupConfig)
+	}
+
+	defaultGroup := GroupConfig{
+		Swap:      true,
+		Exclusive: true,
+		Members:   []string{},
+	}
+	// if groups is empty, create a default group and put
+	// all models into it
+	if len(config.Groups) == 0 {
+		for modelName := range config.Models {
+			defaultGroup.Members = append(defaultGroup.Members, modelName)
+		}
+	} else {
+		// iterate over existing group members and add non-grouped models into the default group
+		for modelName, _ := range config.Models {
+			foundModel := false
+		found:
+			// search for the model in existing groups
+			for _, groupConfig := range config.Groups {
+				for _, member := range groupConfig.Members {
+					if member == modelName {
+						foundModel = true
+						break found
+					}
+				}
+			}
+
+			if !foundModel {
+				defaultGroup.Members = append(defaultGroup.Members, modelName)
+			}
+		}
+	}
+
+	sort.Strings(defaultGroup.Members) // make consistent ordering for testing
+	config.Groups[DEFAULT_GROUP_ID] = defaultGroup
+
+	return config
 }
 
 func SanitizeCommand(cmdStr string) ([]string, error) {

proxy/config_test.go

@@ -35,11 +35,31 @@ models:
     aliases:
       - "m2"
     checkEndpoint: "/"
+  model3:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8081"
+    aliases:
+      - "mthree"
+    checkEndpoint: "/"
+  model4:
+    cmd: path/to/cmd --arg1 one
+    checkEndpoint: "/"
+
 healthCheckTimeout: 15
 profiles:
   test:
     - model1
     - model2
+groups:
+  group1:
+    swap: true
+    exclusive: false
+    members: ["model2"]
+  forever:
+    exclusive: false
+    persistent: true
+    members:
+      - "model4"
 `
 
 	if err := os.WriteFile(tempFile, []byte(content), 0644); err != nil {
@@ -52,7 +72,7 @@ profiles:
 		t.Fatalf("Failed to load config: %v", err)
 	}
 
-	expected := &Config{
+	expected := Config{
 		Models: map[string]ModelConfig{
 			"model1": {
 				Cmd:           "path/to/cmd --arg1 one",
@@ -68,6 +88,17 @@ profiles:
 				Env:           nil,
 				CheckEndpoint: "/",
 			},
+			"model3": {
+				Cmd:           "path/to/cmd --arg1 one",
+				Proxy:         "http://localhost:8081",
+				Aliases:       []string{"mthree"},
+				Env:           nil,
+				CheckEndpoint: "/",
+			},
+			"model4": {
+				Cmd:           "path/to/cmd --arg1 one",
+				CheckEndpoint: "/",
+			},
 		},
 		HealthCheckTimeout: 15,
 		Profiles: map[string][]string{
@@ -77,6 +108,25 @@ profiles:
 			"m1":        "model1",
 			"model-one": "model1",
 			"m2":        "model2",
+			"mthree":    "model3",
+		},
+		Groups: map[string]GroupConfig{
+			DEFAULT_GROUP_ID: {
+				Swap:      true,
+				Exclusive: true,
+				Members:   []string{"model1", "model3"},
+			},
+			"group1": {
+				Swap:      true,
+				Exclusive: false,
+				Members:   []string{"model2"},
+			},
+			"forever": {
+				Swap:       true,
+				Exclusive:  false,
+				Persistent: true,
+				Members:    []string{"model4"},
+			},
 		},
 	}
 
@@ -87,6 +137,51 @@ profiles:
 	assert.Equal(t, "model1", realname)
 }
 
+func TestConfig_GroupMemberIsUnique(t *testing.T) {
+	// Create a temporary YAML file for testing
+	tempDir, err := os.MkdirTemp("", "test-config")
+	if err != nil {
+		t.Fatalf("Failed to create temporary directory: %v", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	tempFile := filepath.Join(tempDir, "config.yaml")
+	content := `
+models:
+  model1:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8080"
+  model2:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8081"
+    checkEndpoint: "/"
+  model3:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8081"
+    checkEndpoint: "/"
+
+healthCheckTimeout: 15
+groups:
+  group1:
+    swap: true
+    exclusive: false
+    members: ["model2"]
+  group2:
+    swap: true
+    exclusive: false
+    members: ["model2"]
+`
+
+	if err := os.WriteFile(tempFile, []byte(content), 0644); err != nil {
+		t.Fatalf("Failed to write temporary file: %v", err)
+	}
+
+	// Load the config and verify
+	_, err = LoadConfig(tempFile)
+	assert.NotNil(t, err)
+
+}
+
 func TestConfig_ModelConfigSanitizedCommand(t *testing.T) {
 	config := &ModelConfig{
 		Cmd: `python model1.py \

proxy/helpers_test.go

@@ -14,6 +14,7 @@ import (
 var (
 	nextTestPort int = 12000
 	portMutex    sync.Mutex
+	testLogger   = NewLogMonitorWriter(os.Stdout)
 )
 
 // Check if the binary exists
@@ -26,6 +27,17 @@ func TestMain(m *testing.M) {
 
 	gin.SetMode(gin.TestMode)
 
+	switch os.Getenv("LOG_LEVEL") {
+	case "debug":
+		testLogger.SetLogLevel(LevelDebug)
+	case "warn":
+		testLogger.SetLogLevel(LevelWarn)
+	case "info":
+		testLogger.SetLogLevel(LevelInfo)
+	default:
+		testLogger.SetLogLevel(LevelWarn)
+	}
+
 	m.Run()
 }
 

proxy/process.go

@@ -301,6 +301,10 @@ func (p *Process) start() error {
 }
 
 func (p *Process) Stop() {
+	if !isValidTransition(p.CurrentState(), StateStopping) {
+		return
+	}
+
 	// wait for any inflight requests before proceeding
 	p.inFlightRequests.Wait()
 	p.proxyLogger.Debugf("<%s> Stopping process", p.ID)

proxy/processgroup.go

@@ -0,0 +1,111 @@
+package proxy
+
+import (
+	"fmt"
+	"net/http"
+	"slices"
+	"sync"
+)
+
+type ProcessGroup struct {
+	sync.Mutex
+
+	config     Config
+	id         string
+	swap       bool
+	exclusive  bool
+	persistent bool
+
+	proxyLogger    *LogMonitor
+	upstreamLogger *LogMonitor
+
+	// map of current processes
+	processes       map[string]*Process
+	lastUsedProcess string
+}
+
+func NewProcessGroup(id string, config Config, proxyLogger *LogMonitor, upstreamLogger *LogMonitor) *ProcessGroup {
+	groupConfig, ok := config.Groups[id]
+	if !ok {
+		panic("Unable to find configuration for group id: " + id)
+	}
+
+	pg := &ProcessGroup{
+		id:             id,
+		config:         config,
+		swap:           groupConfig.Swap,
+		exclusive:      groupConfig.Exclusive,
+		persistent:     groupConfig.Persistent,
+		proxyLogger:    proxyLogger,
+		upstreamLogger: upstreamLogger,
+		processes:      make(map[string]*Process),
+	}
+
+	// Create a Process for each member in the group
+	for _, modelID := range groupConfig.Members {
+		modelConfig, modelID, _ := pg.config.FindConfig(modelID)
+		process := NewProcess(modelID, pg.config.HealthCheckTimeout, modelConfig, pg.upstreamLogger, pg.proxyLogger)
+		pg.processes[modelID] = process
+	}
+
+	return pg
+}
+
+// ProxyRequest proxies a request to the specified model
+func (pg *ProcessGroup) ProxyRequest(modelID string, writer http.ResponseWriter, request *http.Request) error {
+	if !pg.HasMember(modelID) {
+		return fmt.Errorf("model %s not part of group %s", modelID, pg.id)
+	}
+
+	pg.Lock()
+	if pg.swap && pg.lastUsedProcess != modelID {
+		if pg.lastUsedProcess != "" {
+			pg.processes[pg.lastUsedProcess].Stop()
+		}
+		pg.lastUsedProcess = modelID
+	}
+	pg.Unlock()
+
+	pg.processes[modelID].ProxyRequest(writer, request)
+	return nil
+}
+
+func (pg *ProcessGroup) HasMember(modelName string) bool {
+	return slices.Contains(pg.config.Groups[pg.id].Members, modelName)
+}
+
+func (pg *ProcessGroup) StopProcesses() {
+	pg.Lock()
+	defer pg.Unlock()
+	pg.stopProcesses()
+}
+
+// stopProcesses stops all processes in the group
+func (pg *ProcessGroup) stopProcesses() {
+	if len(pg.processes) == 0 {
+		return
+	}
+
+	// stop Processes in parallel
+	var wg sync.WaitGroup
+	for _, process := range pg.processes {
+		wg.Add(1)
+		go func(process *Process) {
+			defer wg.Done()
+			process.Stop()
+		}(process)
+	}
+	wg.Wait()
+}
+
+func (pg *ProcessGroup) Shutdown() {
+	var wg sync.WaitGroup
+	for _, process := range pg.processes {
+		wg.Add(1)
+		go func(process *Process) {
+			defer wg.Done()
+			process.Shutdown()
+		}(process)
+	}
+	wg.Wait()
+}

proxy/processgroup_test.go

@@ -0,0 +1,96 @@
+package proxy
+
+import (
+	"bytes"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var processGroupTestConfig = AddDefaultGroupToConfig(Config{
+	HealthCheckTimeout: 15,
+	Models: map[string]ModelConfig{
+		"model1": getTestSimpleResponderConfig("model1"),
+		"model2": getTestSimpleResponderConfig("model2"),
+		"model3": getTestSimpleResponderConfig("model3"),
+		"model4": getTestSimpleResponderConfig("model4"),
+		"model5": getTestSimpleResponderConfig("model5"),
+	},
+	Groups: map[string]GroupConfig{
+		"G1": {
+			Swap:      true,
+			Exclusive: true,
+			Members:   []string{"model1", "model2"},
+		},
+		"G2": {
+			Swap:      false,
+			Exclusive: true,
+			Members:   []string{"model3", "model4"},
+		},
+	},
+})
+
+func TestProcessGroup_DefaultHasCorrectModel(t *testing.T) {
+	pg := NewProcessGroup(DEFAULT_GROUP_ID, processGroupTestConfig, testLogger, testLogger)
+	assert.True(t, pg.HasMember("model5"))
+}
+
+func TestProcessGroup_HasMember(t *testing.T) {
+	pg := NewProcessGroup("G1", processGroupTestConfig, testLogger, testLogger)
+	assert.True(t, pg.HasMember("model1"))
+	assert.True(t, pg.HasMember("model2"))
+	assert.False(t, pg.HasMember("model3"))
+}
+
+func TestProcessGroup_ProxyRequestSwapIsTrue(t *testing.T) {
+	pg := NewProcessGroup("G1", processGroupTestConfig, testLogger, testLogger)
+	defer pg.StopProcesses()
+
+	tests := []string{"model1", "model2"}
+
+	for _, modelName := range tests {
+		t.Run(modelName, func(t *testing.T) {
+			reqBody := `{"x", "y"}`
+			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+			w := httptest.NewRecorder()
+
+			assert.NoError(t, pg.ProxyRequest(modelName, w, req))
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Contains(t, w.Body.String(), modelName)
+
+			// make sure only one process is in the running state
+			count := 0
+			for _, process := range pg.processes {
+				if process.CurrentState() == StateReady {
+					count++
+				}
+			}
+			assert.Equal(t, 1, count)
+		})
+	}
+}
+
+func TestProcessGroup_ProxyRequestSwapIsFalse(t *testing.T) {
+	pg := NewProcessGroup("G2", processGroupTestConfig, testLogger, testLogger)
+	defer pg.StopProcesses()
+
+	tests := []string{"model3", "model4"}
+
+	for _, modelName := range tests {
+		t.Run(modelName, func(t *testing.T) {
+			reqBody := `{"x", "y"}`
+			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+			w := httptest.NewRecorder()
+			assert.NoError(t, pg.ProxyRequest(modelName, w, req))
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Contains(t, w.Body.String(), modelName)
+		})
+	}
+
+	// make sure all the processes are running
+	for _, process := range pg.processes {
+		assert.Equal(t, StateReady, process.CurrentState())
+	}
+}

proxy/proxymanager.go

@@ -26,17 +26,18 @@ const (
 type ProxyManager struct {
 	sync.Mutex
 
-	config           *Config
-	currentProcesses map[string]*Process
-	ginEngine        *gin.Engine
+	config    Config
+	ginEngine *gin.Engine
 
 	// logging
 	proxyLogger    *LogMonitor
 	upstreamLogger *LogMonitor
 	muxLogger      *LogMonitor
+
+	processGroups map[string]*ProcessGroup
 }
 
-func New(config *Config) *ProxyManager {
+func New(config Config) *ProxyManager {
 	// set up loggers
 	stdoutLogger := NewLogMonitorWriter(os.Stdout)
 	upstreamLogger := NewLogMonitorWriter(stdoutLogger)
@@ -65,13 +66,20 @@ func New(config *Config) *ProxyManager {
 	}
 
 	pm := &ProxyManager{
-		config:           config,
-		currentProcesses: make(map[string]*Process),
-		ginEngine:        gin.New(),
+		config:    config,
+		ginEngine: gin.New(),
 
 		proxyLogger:    proxyLogger,
 		muxLogger:      stdoutLogger,
 		upstreamLogger: upstreamLogger,
+
+		processGroups: make(map[string]*ProcessGroup),
+	}
+
+	// create the process groups
+	for groupID := range config.Groups {
+		processGroup := NewProcessGroup(groupID, config, proxyLogger, upstreamLogger)
+		pm.processGroups[groupID] = processGroup
 	}
 
 	pm.ginEngine.Use(func(c *gin.Context) {
@@ -200,27 +208,17 @@ func (pm *ProxyManager) StopProcesses() {
 	pm.Lock()
 	defer pm.Unlock()
 
-	pm.stopProcesses()
-}
-
-// for internal usage
-func (pm *ProxyManager) stopProcesses() {
-	if len(pm.currentProcesses) == 0 {
-		return
-	}
-
 	// stop Processes in parallel
 	var wg sync.WaitGroup
-	for _, process := range pm.currentProcesses {
+	for _, processGroup := range pm.processGroups {
 		wg.Add(1)
-		go func(process *Process) {
+		go func(processGroup *ProcessGroup) {
 			defer wg.Done()
-			process.Stop()
-		}(process)
+			processGroup.stopProcesses()
+		}(processGroup)
 	}
-	wg.Wait()
 
-	pm.currentProcesses = make(map[string]*Process)
+	wg.Wait()
 }
 
 // Shutdown is called to shutdown all upstream processes
@@ -229,18 +227,44 @@ func (pm *ProxyManager) Shutdown() {
 	pm.Lock()
 	defer pm.Unlock()
 
-	// shutdown process in parallel
+	pm.proxyLogger.Debug("Shutdown() called in proxy manager")
+
 	var wg sync.WaitGroup
-	for _, process := range pm.currentProcesses {
+	// Send shutdown signal to all process in groups
+	for _, processGroup := range pm.processGroups {
 		wg.Add(1)
-		go func(process *Process) {
+		go func(processGroup *ProcessGroup) {
 			defer wg.Done()
-			process.Shutdown()
-		}(process)
+			processGroup.Shutdown()
+		}(processGroup)
 	}
 	wg.Wait()
 }
 
+func (pm *ProxyManager) swapProcessGroup(requestedModel string) (*ProcessGroup, string, error) {
+	// de-alias the real model name and get a real one
+	realModelName, found := pm.config.RealModelName(requestedModel)
+	if !found {
+		return nil, realModelName, fmt.Errorf("could not find real modelID for %s", requestedModel)
+	}
+
+	processGroup := pm.findGroupByModelName(realModelName)
+	if processGroup == nil {
+		return nil, realModelName, fmt.Errorf("could not find process group for model %s", requestedModel)
+	}
+
+	if processGroup.exclusive {
+		pm.proxyLogger.Debugf("Exclusive mode for group %s, stopping other process groups", processGroup.id)
+		for groupId, otherGroup := range pm.processGroups {
+			if groupId != processGroup.id && !otherGroup.persistent {
+				otherGroup.StopProcesses()
+			}
+		}
+	}
+
+	return processGroup, realModelName, nil
+}
+
 func (pm *ProxyManager) listModelsHandler(c *gin.Context) {
 	data := []interface{}{}
 	for id, modelConfig := range pm.config.Models {
@@ -270,79 +294,6 @@ func (pm *ProxyManager) listModelsHandler(c *gin.Context) {
 	}
 }
 
-func (pm *ProxyManager) swapModel(requestedModel string) (*Process, error) {
-	pm.Lock()
-	defer pm.Unlock()
-
-	// Check if requestedModel contains a PROFILE_SPLIT_CHAR
-	profileName, modelName := splitRequestedModel(requestedModel)
-
-	if profileName != "" {
-		if _, found := pm.config.Profiles[profileName]; !found {
-			return nil, fmt.Errorf("model group not found %s", profileName)
-		}
-	}
-
-	// de-alias the real model name and get a real one
-	realModelName, found := pm.config.RealModelName(modelName)
-	if !found {
-		return nil, fmt.Errorf("could not find modelID for %s", requestedModel)
-	}
-
-	// check if model is part of the profile
-	if profileName != "" {
-		found := false
-		for _, item := range pm.config.Profiles[profileName] {
-			if item == realModelName {
-				found = true
-				break
-			}
-		}
-
-		if !found {
-			return nil, fmt.Errorf("model %s part of profile %s", realModelName, profileName)
-		}
-	}
-
-	// exit early when already running, otherwise stop everything and swap
-	requestedProcessKey := ProcessKeyName(profileName, realModelName)
-
-	if process, found := pm.currentProcesses[requestedProcessKey]; found {
-		pm.proxyLogger.Debugf("No-swap, using existing process for model [%s]", requestedModel)
-		return process, nil
-	}
-
-	// stop all running models
-	pm.proxyLogger.Infof("Swapping model to [%s]", requestedModel)
-	pm.stopProcesses()
-	if profileName == "" {
-		modelConfig, modelID, found := pm.config.FindConfig(realModelName)
-		if !found {
-			return nil, fmt.Errorf("could not find configuration for %s", realModelName)
-		}
-
-		process := NewProcess(modelID, pm.config.HealthCheckTimeout, modelConfig, pm.upstreamLogger, pm.proxyLogger)
-		processKey := ProcessKeyName(profileName, modelID)
-		pm.currentProcesses[processKey] = process
-	} else {
-		for _, modelName := range pm.config.Profiles[profileName] {
-			if realModelName, found := pm.config.RealModelName(modelName); found {
-				modelConfig, modelID, found := pm.config.FindConfig(realModelName)
-				if !found {
-					return nil, fmt.Errorf("could not find configuration for %s in group %s", realModelName, profileName)
-				}
-
-				process := NewProcess(modelID, pm.config.HealthCheckTimeout, modelConfig, pm.upstreamLogger, pm.proxyLogger)
-				processKey := ProcessKeyName(profileName, modelID)
-				pm.currentProcesses[processKey] = process
-			}
-		}
-	}
-
-	// requestedProcessKey should exist due to swap
-	return pm.currentProcesses[requestedProcessKey], nil
-}
-
 func (pm *ProxyManager) proxyToUpstream(c *gin.Context) {
 	requestedModel := c.Param("model_id")
 
@@ -351,13 +302,14 @@ func (pm *ProxyManager) proxyToUpstream(c *gin.Context) {
 		return
 	}
 
-	if process, err := pm.swapModel(requestedModel); err != nil {
-		pm.sendErrorResponse(c, http.StatusNotFound, fmt.Sprintf("unable to swap to model, %s", err.Error()))
-	} else {
-		// rewrite the path
-		c.Request.URL.Path = c.Param("upstreamPath")
-		process.ProxyRequest(c.Writer, c.Request)
+	processGroup, _, err := pm.swapProcessGroup(requestedModel)
+	if err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 	}
+
+	// rewrite the path
+	c.Request.URL.Path = c.Param("upstreamPath")
+	processGroup.ProxyRequest(requestedModel, c.Writer, c.Request)
 }
 
 func (pm *ProxyManager) upstreamIndex(c *gin.Context) {
@@ -397,29 +349,19 @@ func (pm *ProxyManager) proxyOAIHandler(c *gin.Context) {
 		pm.sendErrorResponse(c, http.StatusBadRequest, "missing or invalid 'model' key")
 	}
 
-	process, err := pm.swapModel(requestedModel)
-
+	processGroup, realModelName, err := pm.swapProcessGroup(requestedModel)
 	if err != nil {
-		pm.sendErrorResponse(c, http.StatusNotFound, fmt.Sprintf("unable to swap to model, %s", err.Error()))
-		return
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 	}
 
 	// issue #69 allow custom model names to be sent to upstream
-	if process.config.UseModelName != "" {
-		bodyBytes, err = sjson.SetBytes(bodyBytes, "model", process.config.UseModelName)
+	useModelName := pm.config.Models[realModelName].UseModelName
+	if useModelName != "" {
+		bodyBytes, err = sjson.SetBytes(bodyBytes, "model", useModelName)
 		if err != nil {
-			pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error updating JSON: %s", err.Error()))
+			pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error rewriting model name in JSON: %s", err.Error()))
 			return
 		}
-	} else {
-		profileName, modelName := splitRequestedModel(requestedModel)
-		if profileName != "" {
-			bodyBytes, err = sjson.SetBytes(bodyBytes, "model", modelName)
-			if err != nil {
-				pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error updating JSON: %s", err.Error()))
-				return
-			}
-		}
 	}
 
 	c.Request.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
@@ -428,8 +370,10 @@ func (pm *ProxyManager) proxyOAIHandler(c *gin.Context) {
 	c.Request.Header.Del("transfer-encoding")
 	c.Request.Header.Add("content-length", strconv.Itoa(len(bodyBytes)))
 
-	process.ProxyRequest(c.Writer, c.Request)
-
+	if err := processGroup.ProxyRequest(realModelName, c.Writer, c.Request); err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error proxying request: %s", err.Error()))
+		pm.proxyLogger.Errorf("Error Proxying Request for processGroup %s and model %s", processGroup.id, realModelName)
+	}
 }
 
 func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
@@ -451,26 +395,24 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 		return
 	}
 
-	// Swap to the requested model
-	process, err := pm.swapModel(requestedModel)
+	processGroup, realModelName, err := pm.swapProcessGroup(requestedModel)
 	if err != nil {
-		pm.sendErrorResponse(c, http.StatusNotFound, fmt.Sprintf("unable to swap to model, %s", err.Error()))
-		return
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 	}
 
-	// Get profile name and model name from the requested model
-	profileName, modelName := splitRequestedModel(requestedModel)
-
 	// Copy all form values
 	for key, values := range c.Request.MultipartForm.Value {
 		for _, value := range values {
 			fieldValue := value
 			// If this is the model field and we have a profile, use just the model name
 			if key == "model" {
-				if process.config.UseModelName != "" {
-					fieldValue = process.config.UseModelName
-				} else if profileName != "" {
-					fieldValue = modelName
+				// # issue #69 allow custom model names to be sent to upstream
+				useModelName := pm.config.Models[realModelName].UseModelName
+
+				if useModelName != "" {
+					fieldValue = useModelName
+				} else {
+					fieldValue = requestedModel
 				}
 			}
 			field, err := multipartWriter.CreateFormField(key)
@@ -532,7 +474,10 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 	modifiedReq.Header.Set("Content-Type", multipartWriter.FormDataContentType())
 
 	// Use the modified request for proxying
-	process.ProxyRequest(c.Writer, modifiedReq)
+	if err := processGroup.ProxyRequest(realModelName, c.Writer, modifiedReq); err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error proxying request: %s", err.Error()))
+		pm.proxyLogger.Errorf("Error Proxying Request for processGroup %s and model %s", processGroup.id, realModelName)
+	}
 }
 
 func (pm *ProxyManager) sendErrorResponse(c *gin.Context, statusCode int, message string) {
@@ -554,14 +499,15 @@ func (pm *ProxyManager) listRunningProcessesHandler(context *gin.Context) {
 	context.Header("Content-Type", "application/json")
 	runningProcesses := make([]gin.H, 0) // Default to an empty response.
 
-	for _, process := range pm.currentProcesses {
-
-		// Append the process ID and State (multiple entries if profiles are being used).
-		runningProcesses = append(runningProcesses, gin.H{
-			"model": process.ID,
-			"state": process.state,
-		})
-
+	for _, processGroup := range pm.processGroups {
+		for _, process := range processGroup.processes {
+			if process.CurrentState() == StateReady {
+				runningProcesses = append(runningProcesses, gin.H{
+					"model": process.ID,
+					"state": process.state,
+				})
+			}
+		}
 	}
 
 	// Put the results under the `running` key.
@@ -572,15 +518,11 @@ func (pm *ProxyManager) listRunningProcessesHandler(context *gin.Context) {
 	context.JSON(http.StatusOK, response) // Always return 200 OK
 }
 
-func ProcessKeyName(groupName, modelName string) string {
-	return groupName + PROFILE_SPLIT_CHAR + modelName
-}
-
-func splitRequestedModel(requestedModel string) (string, string) {
-	profileName, modelName := "", requestedModel
-	if idx := strings.Index(requestedModel, PROFILE_SPLIT_CHAR); idx != -1 {
-		profileName = requestedModel[:idx]
-		modelName = requestedModel[idx+1:]
+func (pm *ProxyManager) findGroupByModelName(modelName string) *ProcessGroup {
+	for _, group := range pm.processGroups {
+		if group.HasMember(modelName) {
+			return group
+		}
 	}
-	return profileName, modelName
+	return nil
 }

proxy/proxymanager_test.go

@@ -16,14 +16,14 @@ import (
 )
 
 func TestProxyManager_SwapProcessCorrectly(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 			"model2": getTestSimpleResponderConfig("model2"),
 		},
 		LogLevel: "error",
-	}
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
@@ -36,59 +36,91 @@ func TestProxyManager_SwapProcessCorrectly(t *testing.T) {
 		proxy.HandlerFunc(w, req)
 		assert.Equal(t, http.StatusOK, w.Code)
 		assert.Contains(t, w.Body.String(), modelName)
-
-		_, exists := proxy.currentProcesses[ProcessKeyName("", modelName)]
-		assert.True(t, exists, "expected %s key in currentProcesses", modelName)
-
 	}
-
-	// make sure there's only one loaded model
-	assert.Len(t, proxy.currentProcesses, 1)
 }
 
 func TestProxyManager_SwapMultiProcess(t *testing.T) {
-
-	model1 := "path1/model1"
-	model2 := "path2/model2"
-
-	profileModel1 := ProcessKeyName("test", model1)
-	profileModel2 := ProcessKeyName("test", model2)
-
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
-			model1: getTestSimpleResponderConfig("model1"),
-			model2: getTestSimpleResponderConfig("model2"),
-		},
-		Profiles: map[string][]string{
-			"test": {model1, model2},
+			"model1": getTestSimpleResponderConfig("model1"),
+			"model2": getTestSimpleResponderConfig("model2"),
 		},
 		LogLevel: "error",
-	}
+		Groups: map[string]GroupConfig{
+			"G1": {
+				Swap:      true,
+				Exclusive: false,
+				Members:   []string{"model1"},
+			},
+			"G2": {
+				Swap:      true,
+				Exclusive: false,
+				Members:   []string{"model2"},
+			},
+		},
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
 
-	for modelID, requestedModel := range map[string]string{
-		"model1": profileModel1,
-		"model2": profileModel2,
-	} {
+	tests := []string{"model1", "model2"}
+	for _, requestedModel := range tests {
+		t.Run(requestedModel, func(t *testing.T) {
+			reqBody := fmt.Sprintf(`{"model":"%s"}`, requestedModel)
+			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+			w := httptest.NewRecorder()
+
+			proxy.HandlerFunc(w, req)
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Contains(t, w.Body.String(), requestedModel)
+
+		})
+	}
+
+	// make sure there's two loaded models
+	assert.Equal(t, proxy.findGroupByModelName("model1").processes["model1"].CurrentState(), StateReady)
+	assert.Equal(t, proxy.findGroupByModelName("model2").processes["model2"].CurrentState(), StateReady)
+}
+
+// Test that a persistent group is not affected by the swapping behaviour of
+// other groups.
+func TestProxyManager_PersistentGroupsAreNotSwapped(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"), // goes into the default group
+			"model2": getTestSimpleResponderConfig("model2"),
+		},
+		LogLevel: "error",
+		Groups: map[string]GroupConfig{
+			// the forever group is persistent and should not be affected by model1
+			"forever": {
+				Swap:       true,
+				Exclusive:  false,
+				Persistent: true,
+				Members:    []string{"model2"},
+			},
+		},
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses()
+
+	// make requests to load all models, loading model1 should not affect model2
+	tests := []string{"model2", "model1"}
+	for _, requestedModel := range tests {
 		reqBody := fmt.Sprintf(`{"model":"%s"}`, requestedModel)
 		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
 		w := httptest.NewRecorder()
 
 		proxy.HandlerFunc(w, req)
 		assert.Equal(t, http.StatusOK, w.Code)
-		assert.Contains(t, w.Body.String(), modelID)
+		assert.Contains(t, w.Body.String(), requestedModel)
 	}
 
-	// make sure there's two loaded models
-	assert.Len(t, proxy.currentProcesses, 2)
-	_, exists := proxy.currentProcesses[profileModel1]
-	assert.True(t, exists, "expected "+profileModel1+" key in currentProcesses")
-
-	_, exists = proxy.currentProcesses[profileModel2]
-	assert.True(t, exists, "expected "+profileModel2+" key in currentProcesses")
+	assert.Equal(t, proxy.findGroupByModelName("model2").processes["model2"].CurrentState(), StateReady)
+	assert.Equal(t, proxy.findGroupByModelName("model1").processes["model1"].CurrentState(), StateReady)
 }
 
 // When a request for a different model comes in ProxyManager should wait until
@@ -98,7 +130,7 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 		t.Skip("skipping slow test")
 	}
 
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
@@ -106,7 +138,7 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 			"model3": getTestSimpleResponderConfig("model3"),
 		},
 		LogLevel: "error",
-	}
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
@@ -149,7 +181,7 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 }
 
 func TestProxyManager_ListModelsHandler(t *testing.T) {
-	config := &Config{
+	config := Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
@@ -217,51 +249,6 @@ func TestProxyManager_ListModelsHandler(t *testing.T) {
 	assert.Empty(t, expectedModels, "not all expected models were returned")
 }
 
-func TestProxyManager_ProfileNonMember(t *testing.T) {
-
-	model1 := "path1/model1"
-	model2 := "path2/model2"
-
-	profileMemberName := ProcessKeyName("test", model1)
-	profileNonMemberName := ProcessKeyName("test", model2)
-
-	config := &Config{
-		HealthCheckTimeout: 15,
-		Models: map[string]ModelConfig{
-			model1: getTestSimpleResponderConfig("model1"),
-			model2: getTestSimpleResponderConfig("model2"),
-		},
-		Profiles: map[string][]string{
-			"test": {model1},
-		},
-		LogLevel: "error",
-	}
-
-	proxy := New(config)
-	defer proxy.StopProcesses()
-
-	// actual member of profile
-	{
-		reqBody := fmt.Sprintf(`{"model":"%s"}`, profileMemberName)
-		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-		w := httptest.NewRecorder()
-
-		proxy.HandlerFunc(w, req)
-		assert.Equal(t, http.StatusOK, w.Code)
-		assert.Contains(t, w.Body.String(), "model1")
-	}
-
-	// actual model, but non-member will 404
-	{
-		reqBody := fmt.Sprintf(`{"model":"%s"}`, profileNonMemberName)
-		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-		w := httptest.NewRecorder()
-
-		proxy.HandlerFunc(w, req)
-		assert.Equal(t, http.StatusNotFound, w.Code)
-	}
-}
-
 func TestProxyManager_Shutdown(t *testing.T) {
 	// make broken model configurations
 	model1Config := getTestSimpleResponderConfigPort("model1", 9991)
@@ -273,24 +260,27 @@ func TestProxyManager_Shutdown(t *testing.T) {
 	model3Config := getTestSimpleResponderConfigPort("model3", 9993)
 	model3Config.Proxy = "http://localhost:10003/"
 
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"model1", "model2", "model3"},
-		},
 		Models: map[string]ModelConfig{
 			"model1": model1Config,
 			"model2": model2Config,
 			"model3": model3Config,
 		},
 		LogLevel: "error",
-	}
+		Groups: map[string]GroupConfig{
+			"test": {
+				Swap:    false,
+				Members: []string{"model1", "model2", "model3"},
+			},
+		},
+	})
 
 	proxy := New(config)
 
 	// Start all the processes
 	var wg sync.WaitGroup
-	for _, modelName := range []string{"test:model1", "test:model2", "test:model3"} {
+	for _, modelName := range []string{"model1", "model2", "model3"} {
 		wg.Add(1)
 		go func(modelName string) {
 			defer wg.Done()
@@ -298,11 +288,10 @@ func TestProxyManager_Shutdown(t *testing.T) {
 			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
 			w := httptest.NewRecorder()
 
-			// send a request to trigger the proxy to load
+			// send a request to trigger the proxy to load ... this should hang waiting for start up
 			proxy.HandlerFunc(w, req)
 			assert.Equal(t, http.StatusBadGateway, w.Code)
 			assert.Contains(t, w.Body.String(), "health check interrupted due to shutdown")
-			//fmt.Println(w.Code, w.Body.String())
 		}(modelName)
 	}
 
@@ -314,67 +303,44 @@ func TestProxyManager_Shutdown(t *testing.T) {
 }
 
 func TestProxyManager_Unload(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 		},
 		LogLevel: "error",
-	}
+	})
 
 	proxy := New(config)
-	proc, err := proxy.swapModel("model1")
-	assert.NoError(t, err)
-	assert.NotNil(t, proc)
-
-	assert.Len(t, proxy.currentProcesses, 1)
-	req := httptest.NewRequest("GET", "/unload", nil)
+	reqBody := fmt.Sprintf(`{"model":"%s"}`, "model1")
+	req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
 	w := httptest.NewRecorder()
 	proxy.HandlerFunc(w, req)
+
+	assert.Equal(t, proxy.processGroups[DEFAULT_GROUP_ID].processes["model1"].CurrentState(), StateReady)
+	req = httptest.NewRequest("GET", "/unload", nil)
+	w = httptest.NewRecorder()
+	proxy.HandlerFunc(w, req)
 	assert.Equal(t, http.StatusOK, w.Code)
 	assert.Equal(t, w.Body.String(), "OK")
-	assert.Len(t, proxy.currentProcesses, 0)
-}
 
-// issue 62, strip profile slug from model name
-func TestProxyManager_StripProfileSlug(t *testing.T) {
-	config := &Config{
-		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"TheExpectedModel"}, // TheExpectedModel is default in simple-responder.go
-		},
-		Models: map[string]ModelConfig{
-			"TheExpectedModel": getTestSimpleResponderConfig("TheExpectedModel"),
-		},
-		LogLevel: "error",
-	}
-
-	proxy := New(config)
-	defer proxy.StopProcesses()
-
-	reqBody := fmt.Sprintf(`{"model":"%s"}`, "test:TheExpectedModel")
-	req := httptest.NewRequest("POST", "/v1/audio/speech", bytes.NewBufferString(reqBody))
-	w := httptest.NewRecorder()
-	proxy.HandlerFunc(w, req)
-	assert.Equal(t, http.StatusOK, w.Code)
-	assert.Contains(t, w.Body.String(), "ok")
+	// give it a bit of time to stop
+	<-time.After(time.Millisecond * 250)
+	assert.Equal(t, proxy.processGroups[DEFAULT_GROUP_ID].processes["model1"].CurrentState(), StateStopped)
 }
 
 // Test issue #61 `Listing the current list of models and the loaded model.`
 func TestProxyManager_RunningEndpoint(t *testing.T) {
 
 	// Shared configuration
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 			"model2": getTestSimpleResponderConfig("model2"),
 		},
-		Profiles: map[string][]string{
-			"test": {"model1", "model2"},
-		},
-		LogLevel: "error",
-	}
+		LogLevel: "debug",
+	})
 
 	// Define a helper struct to parse the JSON response.
 	type RunningResponse struct {
@@ -429,238 +395,126 @@ func TestProxyManager_RunningEndpoint(t *testing.T) {
 		// Is the model loaded?
 		assert.Equal(t, "ready", response.Running[0].State)
 	})
-
-	t.Run("multiple models via profile", func(t *testing.T) {
-		// Load more than one model.
-		for _, model := range []string{"model1", "model2"} {
-			profileModel := ProcessKeyName("test", model)
-			reqBody := fmt.Sprintf(`{"model":"%s"}`, profileModel)
-			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-			w := httptest.NewRecorder()
-			proxy.HandlerFunc(w, req)
-			assert.Equal(t, http.StatusOK, w.Code)
-		}
-
-		// Simulate the browser call.
-		req := httptest.NewRequest("GET", "/running", nil)
-		w := httptest.NewRecorder()
-		proxy.HandlerFunc(w, req)
-
-		var response RunningResponse
-
-		// The JSON response must be valid.
-		assert.NoError(t, json.Unmarshal(w.Body.Bytes(), &response))
-
-		// The response should contain 2 models.
-		assert.Len(t, response.Running, 2)
-
-		expectedModels := map[string]struct{}{
-			"model1": {},
-			"model2": {},
-		}
-
-		// Iterate through the models and check their states as well.
-		for _, entry := range response.Running {
-			_, exists := expectedModels[entry.Model]
-			assert.True(t, exists, "unexpected model %s", entry.Model)
-			assert.Equal(t, "ready", entry.State)
-			delete(expectedModels, entry.Model)
-		}
-
-		// Since we deleted each model while testing for its validity we should have no more models in the response.
-		assert.Empty(t, expectedModels, "unexpected additional models in response")
-	})
 }
 
 func TestProxyManager_AudioTranscriptionHandler(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"TheExpectedModel"},
-		},
 		Models: map[string]ModelConfig{
 			"TheExpectedModel": getTestSimpleResponderConfig("TheExpectedModel"),
 		},
 		LogLevel: "error",
-	}
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
 
-	testCases := []struct {
-		name        string
-		modelInput  string
-		expectModel string
-	}{
-		{
-			name:        "With Profile Prefix",
-			modelInput:  "test:TheExpectedModel",
-			expectModel: "TheExpectedModel", // Profile prefix should be stripped
-		},
-		{
-			name:        "Without Profile Prefix",
-			modelInput:  "TheExpectedModel",
-			expectModel: "TheExpectedModel", // Should remain the same
-		},
-	}
+	// Create a buffer with multipart form data
+	var b bytes.Buffer
+	w := multipart.NewWriter(&b)
 
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			// Create a buffer with multipart form data
-			var b bytes.Buffer
-			w := multipart.NewWriter(&b)
+	// Add the model field
+	fw, err := w.CreateFormField("model")
+	assert.NoError(t, err)
+	_, err = fw.Write([]byte("TheExpectedModel"))
+	assert.NoError(t, err)
 
-			// Add the model field
-			fw, err := w.CreateFormField("model")
-			assert.NoError(t, err)
-			_, err = fw.Write([]byte(tc.modelInput))
-			assert.NoError(t, err)
+	// Add a file field
+	fw, err = w.CreateFormFile("file", "test.mp3")
+	assert.NoError(t, err)
+	// Generate random content length between 10 and 20
+	contentLength := rand.Intn(11) + 10 // 10 to 20
+	content := make([]byte, contentLength)
+	_, err = fw.Write(content)
+	assert.NoError(t, err)
+	w.Close()
 
-			// Add a file field
-			fw, err = w.CreateFormFile("file", "test.mp3")
-			assert.NoError(t, err)
-			// Generate random content length between 10 and 20
-			contentLength := rand.Intn(11) + 10 // 10 to 20
-			content := make([]byte, contentLength)
-			_, err = fw.Write(content)
-			assert.NoError(t, err)
-			w.Close()
+	// Create the request with the multipart form data
+	req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
+	req.Header.Set("Content-Type", w.FormDataContentType())
+	rec := httptest.NewRecorder()
+	proxy.HandlerFunc(rec, req)
 
-			// Create the request with the multipart form data
-			req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
-			req.Header.Set("Content-Type", w.FormDataContentType())
-			rec := httptest.NewRecorder()
-			proxy.HandlerFunc(rec, req)
-
-			// Verify the response
-			assert.Equal(t, http.StatusOK, rec.Code)
-			var response map[string]string
-			err = json.Unmarshal(rec.Body.Bytes(), &response)
-			assert.NoError(t, err)
-			assert.Equal(t, tc.expectModel, response["model"])
-			assert.Equal(t, response["text"], fmt.Sprintf("The length of the file is %d bytes", contentLength)) // matches simple-responder
-		})
-	}
-}
-
-func TestProxyManager_SplitRequestedModel(t *testing.T) {
-
-	tests := []struct {
-		name            string
-		requestedModel  string
-		expectedProfile string
-		expectedModel   string
-	}{
-		{"no profile", "gpt-4", "", "gpt-4"},
-		{"with profile", "profile1:gpt-4", "profile1", "gpt-4"},
-		{"only profile", "profile1:", "profile1", ""},
-		{"empty model", ":gpt-4", "", "gpt-4"},
-		{"empty profile", ":", "", ""},
-		{"no split char", "gpt-4", "", "gpt-4"},
-		{"profile and model with delimiter", "profile1:delimiter:gpt-4", "profile1", "delimiter:gpt-4"},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			profileName, modelName := splitRequestedModel(tt.requestedModel)
-			if profileName != tt.expectedProfile {
-				t.Errorf("splitRequestedModel(%q) = %q, %q; want %q, %q", tt.requestedModel, profileName, modelName, tt.expectedProfile, tt.expectedModel)
-			}
-			if modelName != tt.expectedModel {
-				t.Errorf("splitRequestedModel(%q) = %q, %q; want %q, %q", tt.requestedModel, profileName, modelName, tt.expectedProfile, tt.expectedModel)
-			}
-		})
-	}
+	// Verify the response
+	assert.Equal(t, http.StatusOK, rec.Code)
+	var response map[string]string
+	err = json.Unmarshal(rec.Body.Bytes(), &response)
+	assert.NoError(t, err)
+	assert.Equal(t, "TheExpectedModel", response["model"])
+	assert.Equal(t, response["text"], fmt.Sprintf("The length of the file is %d bytes", contentLength)) // matches simple-responder
 }
 
 // Test useModelName in configuration sends overrides what is sent to upstream
 func TestProxyManager_UseModelName(t *testing.T) {
-
 	upstreamModelName := "upstreamModel"
 
 	modelConfig := getTestSimpleResponderConfig(upstreamModelName)
 	modelConfig.UseModelName = upstreamModelName
 
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"model1"},
-		},
-
 		Models: map[string]ModelConfig{
 			"model1": modelConfig,
 		},
-
 		LogLevel: "error",
-	}
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
 
-	tests := []struct {
-		description    string
-		requestedModel string
-	}{
-		{"useModelName over rides requested model", "model1"},
-		{"useModelName over rides requested profile:model", "test:model1"},
-	}
+	requestedModel := "model1"
 
-	for _, tt := range tests {
-		t.Run(tt.description+": /v1/chat/completions", func(t *testing.T) {
-			reqBody := fmt.Sprintf(`{"model":"%s"}`, tt.requestedModel)
-			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-			w := httptest.NewRecorder()
+	t.Run("useModelName over rides requested model: /v1/chat/completions", func(t *testing.T) {
+		reqBody := fmt.Sprintf(`{"model":"%s"}`, requestedModel)
+		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+		w := httptest.NewRecorder()
 
-			proxy.HandlerFunc(w, req)
-			assert.Equal(t, http.StatusOK, w.Code)
-			assert.Contains(t, w.Body.String(), upstreamModelName)
+		proxy.HandlerFunc(w, req)
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Body.String(), upstreamModelName)
+	})
 
-		})
-	}
+	t.Run("useModelName over rides requested model: /v1/audio/transcriptions", func(t *testing.T) {
+		// Create a buffer with multipart form data
+		var b bytes.Buffer
+		w := multipart.NewWriter(&b)
 
-	for _, tt := range tests {
-		t.Run(tt.description+": /v1/audio/transcriptions", func(t *testing.T) {
-			// Create a buffer with multipart form data
-			var b bytes.Buffer
-			w := multipart.NewWriter(&b)
+		// Add the model field
+		fw, err := w.CreateFormField("model")
+		assert.NoError(t, err)
+		_, err = fw.Write([]byte(requestedModel))
+		assert.NoError(t, err)
 
-			// Add the model field
-			fw, err := w.CreateFormField("model")
-			assert.NoError(t, err)
-			_, err = fw.Write([]byte(tt.requestedModel))
-			assert.NoError(t, err)
+		// Add a file field
+		fw, err = w.CreateFormFile("file", "test.mp3")
+		assert.NoError(t, err)
+		_, err = fw.Write([]byte("test"))
+		assert.NoError(t, err)
+		w.Close()
 
-			// Add a file field
-			fw, err = w.CreateFormFile("file", "test.mp3")
-			assert.NoError(t, err)
-			_, err = fw.Write([]byte("test"))
-			assert.NoError(t, err)
-			w.Close()
+		// Create the request with the multipart form data
+		req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
+		req.Header.Set("Content-Type", w.FormDataContentType())
+		rec := httptest.NewRecorder()
+		proxy.HandlerFunc(rec, req)
 
-			// Create the request with the multipart form data
-			req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
-			req.Header.Set("Content-Type", w.FormDataContentType())
-			rec := httptest.NewRecorder()
-			proxy.HandlerFunc(rec, req)
-
-			// Verify the response
-			assert.Equal(t, http.StatusOK, rec.Code)
-			var response map[string]string
-			err = json.Unmarshal(rec.Body.Bytes(), &response)
-			assert.NoError(t, err)
-			assert.Equal(t, upstreamModelName, response["model"])
-		})
-	}
+		// Verify the response
+		assert.Equal(t, http.StatusOK, rec.Code)
+		var response map[string]string
+		err = json.Unmarshal(rec.Body.Bytes(), &response)
+		assert.NoError(t, err)
+		assert.Equal(t, upstreamModelName, response["model"])
+	})
 }
 
 func TestProxyManager_CORSOptionsHandler(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 		},
 		LogLevel: "error",
-	}
+	})
 
 	tests := []struct {
 		name            string
@@ -720,3 +574,21 @@ func TestProxyManager_CORSOptionsHandler(t *testing.T) {
 		})
 	}
 }
+
+func TestProxyManager_Upstream(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses()
+	req := httptest.NewRequest("GET", "/upstream/model1/test", nil)
+	rec := httptest.NewRecorder()
+	proxy.HandlerFunc(rec, req)
+	assert.Equal(t, http.StatusOK, rec.Code)
+	assert.Equal(t, "model1", rec.Body.String())
+}