add gmail_sender sample

gmail_sender.py

@@ -0,0 +1,78 @@
+import httplib2
+import os
+
+import apiclient
+import oauth2client
+import argparse
+flags = argparse.ArgumentParser(
+    parents=[oauth2client.tools.argparser]
+).parse_args()
+
+import base64
+from email.mime.text import MIMEText
+from email.utils import formatdate
+import traceback
+
+# If modifying these scopes, delete your previously saved credentials
+# at ~/.credentials/gmail-python-quickstart.json
+SCOPES = "https://www.googleapis.com/auth/gmail.send"
+CLIENT_SECRET_FILE = "client_secret.json"
+APPLICATION_NAME = "MyGmailSender"
+
+MAIL_FROM = "example@gmail.com"
+MAIL_TO = "example+alias@gmail.com"
+
+def get_credentials():
+    script_dir =os.path.abspath(os.path.dirname(__file__)) 
+    credential_dir = os.path.join(script_dir, ".credentials")
+
+    if not os.path.exists(credential_dir):
+        os.makedirs(credential_dir)
+    credential_path = os.path.join(credential_dir,
+                                   "my-gmail-sender.json")
+
+    store = oauth2client.file.Storage(credential_path)
+    credentials = store.get()
+    if not credentials or credentials.invalid:
+        flow = oauth2client.client.flow_from_clientsecrets(CLIENT_SECRET_FILE, SCOPES)
+        flow.user_agent = APPLICATION_NAME
+        credentials = oauth2client.tools.run_flow(flow, store, flags)
+        print("Storing credentials to " + credential_path)
+    return credentials
+
+
+def create_message():
+    message = MIMEText("Gmail body: Hello world!")
+    message["from"] = MAIL_FROM
+    message["to"] = MAIL_TO
+    message["subject"] = "gmail api test"
+    message["Date"] = formatdate(localtime=True)
+
+    byte_msg = message.as_string().encode(encoding="UTF-8")
+    byte_msg_b64encoded = base64.urlsafe_b64encode(byte_msg)
+    str_msg_b64encoded = byte_msg_b64encoded.decode(encoding="UTF-8")
+
+    return {"raw": str_msg_b64encoded}
+
+
+def main():
+    credentials = get_credentials()
+    http = credentials.authorize(httplib2.Http())
+    service = apiclient.discovery.build("gmail", "v1", http=http)
+
+    try:
+        result = service.users().messages().send(
+            userId=MAIL_FROM,
+            body=create_message()
+        ).execute()
+
+        print("Message Id: {}".format(result["id"]))
+
+    except apiclient.errors.HttpError:
+        print("------start trace------")
+        traceback.print_exc()
+        print("------end trace------")
+
+
+if __name__ == "__main__":
+    main()