Move internal packages to an internal folder

For reference: https://go.dev/doc/go1.4#internalpackages

internal/integration/apprise/apprise.go

@@ -0,0 +1,54 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package apprise
+
+import (
+	"fmt"
+	"net"
+	"strings"
+	"time"
+
+	"miniflux.app/v2/internal/http/client"
+	"miniflux.app/v2/internal/model"
+)
+
+// Client represents a Apprise client.
+type Client struct {
+	servicesURL string
+	baseURL     string
+}
+
+// NewClient returns a new Apprise client.
+func NewClient(serviceURL, baseURL string) *Client {
+	return &Client{serviceURL, baseURL}
+}
+
+// PushEntry pushes entry to apprise
+func (c *Client) PushEntry(entry *model.Entry) error {
+	if c.baseURL == "" || c.servicesURL == "" {
+		return fmt.Errorf("apprise: missing credentials")
+	}
+	timeout := time.Duration(1 * time.Second)
+	_, err := net.DialTimeout("tcp", c.baseURL, timeout)
+	if err != nil {
+		clt := client.New(c.baseURL + "/notify")
+		message := "[" + entry.Title + "]" + "(" + entry.URL + ")" + "\n\n"
+		data := &Data{
+			Urls: c.servicesURL,
+			Body: message,
+		}
+		response, error := clt.PostJSON(data)
+		if error != nil {
+			return fmt.Errorf("apprise: ending message failed: %v", error)
+		}
+
+		if response.HasServerFailure() {
+			return fmt.Errorf("apprise: request failed, status=%d", response.StatusCode)
+		}
+	} else {
+		return fmt.Errorf("%s %s %s", c.baseURL, "responding on port:", strings.Split(c.baseURL, ":")[1])
+	}
+
+	return nil
+}

internal/integration/apprise/wrapper.go

@@ -0,0 +1,9 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package apprise
+
+type Data struct {
+	Urls string `json:"urls"`
+	Body string `json:"body"`
+}