X-Git-Url: https://git.giacomolli.uk/onehouse/blobdiff_plain/db3091ee257788c92421a5b8b1af49d429ce8f8e..HEAD:/driver/alamo/http_client.go

diff --git a/driver/alamo/http_client.go b/driver/alamo/http_client.go
index ac00dfc..4c645f4 100644
--- a/driver/alamo/http_client.go
+++ b/driver/alamo/http_client.go
@@ -14,8 +14,8 @@ import (
 )
 
 const (
-	gatewayRequestTimeout = 5 * time.Second
-	gatewayResponseLimit  = 64 * 1024
+	httpRequestTimeout   = 5 * time.Second
+	gatewayResponseLimit = 64 * 1024
 )
 
 // HTTPClient exchanges bounded GET requests with one HTTP gateway origin. Each
@@ -54,49 +54,8 @@ func (c *HTTPClient) Status(ctx context.Context) ([]State, error) {
 	return c.exchange(ctx, "/status", nil)
 }
 
-// Action changes one field or reads a thermostat, and returns its complete
-// readback. It rejects a response for another MAC or more than one thermostat.
-func (c *HTTPClient) Action(ctx context.Context, mac string, action Action) (State, error) {
-	mac, err := normalizeMAC(mac)
-	if err != nil {
-		return State{}, fmt.Errorf("validate action MAC: %w", err)
-	}
-
-	if action.Power != nil && action.TargetTemperature != nil {
-		return State{}, fmt.Errorf("action must change at most one field")
-	}
-
-	query := url.Values{"mac": {mac}}
-	if action.Power != nil {
-		query.Set("power", "0")
-
-		if *action.Power {
-			query.Set("power", "1")
-		}
-	}
-
-	if action.TargetTemperature != nil {
-		if !finite(*action.TargetTemperature) {
-			return State{}, fmt.Errorf("target temperature must be finite")
-		}
-
-		query.Set("stemp", strconv.FormatFloat(*action.TargetTemperature, 'f', -1, 64))
-	}
-
-	states, err := c.exchange(ctx, "/acao", query)
-	if err != nil {
-		return State{}, fmt.Errorf("exchange action: %w", err)
-	}
-
-	if len(states) != 1 || states[0].MAC != mac {
-		return State{}, fmt.Errorf("action response must contain the requested thermostat only")
-	}
-
-	return states[0], nil
-}
-
 func (c *HTTPClient) exchange(ctx context.Context, path string, query url.Values) (states []State, err error) {
-	ctx, cancel := context.WithTimeout(ctx, gatewayRequestTimeout)
+	ctx, cancel := context.WithTimeout(ctx, httpRequestTimeout)
 	defer cancel()
 
 	address := c.origin + path
@@ -111,11 +70,7 @@ func (c *HTTPClient) exchange(ctx context.Context, path string, query url.Values
 
 	response, err := c.client.Do(request)
 	if err != nil {
-		if ctx.Err() != nil {
-			return nil, ctx.Err()
-		}
-
-		return nil, fmt.Errorf("send gateway request")
+		return nil, fmt.Errorf("send gateway request: %w", safeRequestError(err))
 	}
 
 	defer func() {
@@ -131,11 +86,7 @@ func (c *HTTPClient) exchange(ctx context.Context, path string, query url.Values
 
 	body, err := io.ReadAll(io.LimitReader(response.Body, gatewayResponseLimit+1))
 	if err != nil {
-		if ctx.Err() != nil {
-			return nil, ctx.Err()
-		}
-
-		return nil, fmt.Errorf("read gateway response")
+		return nil, fmt.Errorf("read gateway response: %w", safeRequestError(err))
 	}
 
 	if len(body) > gatewayResponseLimit {
@@ -152,9 +103,11 @@ func (c *HTTPClient) exchange(ctx context.Context, path string, query url.Values
 	seen := make(map[string]bool, len(records))
 
 	for _, record := range records {
-		state, recordErr := record.state()
-		if recordErr != nil {
-			return nil, fmt.Errorf("validate gateway record: %w", recordErr)
+		var state State
+
+		state, err = record.state()
+		if err != nil {
+			return nil, fmt.Errorf("validate gateway record: %w", err)
 		}
 
 		if seen[state.MAC] {
@@ -167,3 +120,70 @@ func (c *HTTPClient) exchange(ctx context.Context, path string, query url.Values
 
 	return states, nil
 }
+
+// Action changes one field or reads a thermostat, and returns its complete
+// readback. It rejects a response for another MAC or more than one thermostat.
+func (c *HTTPClient) Action(ctx context.Context, mac string, action Action) (State, error) {
+	mac, err := normalizeMAC(mac)
+	if err != nil {
+		return State{}, fmt.Errorf("validate action MAC: %w", err)
+	}
+
+	if action.Power != nil && action.TargetTemperature != nil {
+		return State{}, fmt.Errorf("action must change at most one field")
+	}
+
+	query := url.Values{"mac": {mac}}
+	if action.Power != nil {
+		query.Set("power", "0")
+
+		if *action.Power {
+			query.Set("power", "1")
+		}
+	}
+
+	if action.TargetTemperature != nil {
+		if !finite(*action.TargetTemperature) {
+			return State{}, fmt.Errorf("target temperature must be finite")
+		}
+
+		query.Set("stemp", strconv.FormatFloat(*action.TargetTemperature, 'f', -1, 64))
+	}
+
+	states, err := c.exchange(ctx, "/acao", query)
+	if err != nil {
+		return State{}, fmt.Errorf("exchange action: %w", err)
+	}
+
+	if len(states) != 1 || states[0].MAC != mac {
+		return State{}, fmt.Errorf("action response must contain the requested thermostat only")
+	}
+
+	return states[0], nil
+}
+
+func safeRequestError(err error) error {
+	var joined interface{ Unwrap() []error }
+
+	if errors.As(err, &joined) {
+		var causes []error
+
+		for _, cause := range joined.Unwrap() {
+			if cause != nil {
+				causes = append(causes, safeRequestError(cause))
+			}
+		}
+
+		return errors.Join(causes...)
+	}
+
+	if errors.Is(err, context.Canceled) {
+		return context.Canceled
+	}
+
+	if errors.Is(err, context.DeadlineExceeded) {
+		return context.DeadlineExceeded
+	}
+
+	return fmt.Errorf("gateway transport failed")
+}