Frames

As is typical with interactive videotex systems, pages are numbered from 0 to 999999999 and consist of one or more frames with the suffix a-z, for example the first frame for page 200 would be 200a, the second 200b and so on (see Routing) for more details). These frames are stored within TELSTAR's database as JSON objects (see https://www.json.org/) and uploaded to Telstar using a simple command line utility.

The Telstar utility program simply interacts with the Telstar API which is a restful API. This can be used directly by any software making it simple to programitically manage pages and routing information.

Frames are defined in JSON. The simplest frame that can be viewed on TELSTAR would be as follows. This would create a simple information frame with some default content.

   {
     "pid": {
       "page-no": 101,
       "frame-id": "a"
     },
     "visible": true,
   }

The Telstar API can be used to add this and other frames to the system (see below).

Shown below is a more complete example of a JSON defined frame. With this particular frame, the actual viewdata content has been created using the editor at http://edit.tf, this can be seen in the content.data and content.type keys. The example below is a simple information page with some simple routing (see Routing). Clicking the content.data link, or pasteing the value into a browser will show the page and allow it to be edited. It is not necessary to use the http://edit.tf editor, this is just one possible option.

   {
     "pid": {
       "page-no": 0,
       "frame-id": "a"
     },
     "visible": true,
     "frame-type": "information",
     "content": {
       "data": "http://edit.tf/#0:QIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQMMKAbNw6dyCTuyZfCBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgKJEiRIkSJEiRIkSJEiRIkSJEiRIkSJEiRIkSJEiRIkSJEiRAxQR4s6LSgzEEmdUi0otOogkzo0-lNg1JM-cCg8unNYgQIASBBj67OnXllWIMu7pl5dMOndty7uixBoy4dnTQsQIECBAgBIEHfLh2dNCDDuyINmnNl59POzKuQIECBAgQIECBAgQIECBAyQTotemggzoiCvFg1JEWkCnYemnfuw7EGHdkQIECBAgQIASBBp3dMvLdh6ad-7DsQbsvfmgw7siDvlw9NGXkuQIECBAgQM0EKrTkzotOmgkzo0-lNg1JM-cCh79vDDu8oMO7IgQIECAEgQYuvPTuy8-aDdl781wM6EjVKcVBMw9MvPogoctOPLzQIEDRBHn1otKdNizqiCTOjT6U2DUkz5wKlvw5OaxByw6dixAgBIEGHdkQUMPLZpw7cu7ouQIECBAgQIECBAgQIECBAgQIECBA2QR4NSLXg2UFOLSrSYcWmCnWKkWYsQVIsWNBsLEEOHMaIASBBh3ZEHTRlQQ9-zfz54diCHh7ZUGHJ2y7unXllXIECBAgQN0EifMkxINmmCqcsPbLsQYd2RBI37NOTD5QbsvfmuQIECBA4CHQc2TDpT50WogcMGCAScgoOnLTi69MqDpvQdNGnmgQIAaBBzy8u2nHlQd9PTQgqZdmXnvzdO-HllQYd2RBt38sq5AgQOQ0yfHQT40ZYgp2adSLNQSZ0aegTIKkWnUQUIMeLTQIECAokSJEiRIkSJEiRIkSJEiRIkSJEiRIkSJEiRIkSJEiRIkSJEFeLBqSItJBGn0osODTqIBIM6EQIEFDDnyoFTJywvoECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECA",
       "type": "edit.tf"
     },
     "routing-table": [0,1,11,3,400,5,6,7,800,9,0],
     "cursor": false,
   }

Adding Frames to the System

Frames can be added to the system using either the Telstar API or by using a plug-in (see Implementing Plugins)

The Telstar API, in conjunction with the cross platform Telstar Util software, provides a simple method of creating and managing pages.

The API can be used to retrieve and update frames and configuring routing. The API is a restful API that uses the GET, PUT, POST and DELETE HTTP methods and as such can be used from any application.

Data is passed to and from the API in JSON format, making the system very simple to use in any programming language. The whole API could be used without any programming at all by using a command line utility such as CURL.

Further details of the Telstar API can be found in the section The Telstar API.

Frame Types

TELSTAR supports many different types of frame, including response frames that can capture user data and gateway frames that provide connectivity to other systems.

The following frame types can exist within Telstar.

• initial: The very first frame a user sees.
• mainindex: The main index frame of the system.
• information: General information frame.
• exit: The final goodbye frame.
• gateway: Gateway frame to other systems (see Gateway Frames
• test: Renders the full 24 lines of data i.e. no header or system rows are rendered.
• telesoftware: Telesoftware frames (see Telesoftware Frames).
• response: Response frames (see Response Frames and Implementing Plugins).
• system: Reserved for use internally.
• exception: Reserved for use internally.

The Basic Frame

Frames are defined in JSON. The simplest frame that can be viewed on TELSTAR would be as follows.

{ "pid": { "page-no": 101, "frame-id": "a" }, "visible": true }

This frame, if posted to the TELSTAR API would result in a simple welcome message being displayed when viewed on TELSTAR using an appropriate videotex client.

To hide the frame from view, simply set the *visible key* to false.

Adding Content with the Edit.tf editor

There are several ways to add content to a page. One of the easiest is to create the page in an editor such as http://edit.tf.

The JSON file would look something like the one showm below. Note that the content type is set to editf and the content data contains the edit.tf url.

   {
       "pid": {
           "page-no": 101,
           "frame-id": "a"
       },
       "visible": true,
       "frame-type": "information",
       "content": {
           "data": "http://edit.tf/#0:QIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQICn_OmTJkSJApUqVKlSpUlcHApiTJkyZEiRIkyZMmTIkSJFmKf3JX58____RBg-fPnzog__2iBBo-fNX9qgQcOHDh8-fGiAp_zFf______2v7_____7X___oEGr__Qa0ur_________QoCn9ywK__6D__a__7dH__tf___1QIv_9AiQIkaPX_bo0aMpiKf_-Yr__oP_9r__tUH_-1____9og__yjnz5cldX9qUc-fPkp__uSv_-g__2v_-1Qf_7X__aIv____KZv_dIV__2pTN___yn__mK___z__a____5__tf_9qgVf__8o5_vWJX__alHP___Kf_7kr____6dBr_____-h__2qBBr__ymbPnSFf69CUzf__8pnz5iq9ejRoECBWvXr0KBGjQYOHBHz4cECBAgwcCily7__yqDhw4ePnzogQeP7RAg0fPiBB___9X___QYPH___-sCmb__KoP________3B__tUCDV__tUH___1f36XB-_______KOf_8qgRo__9B__v9X___QINX___Qav__B8-NNX_-jR___8pm__ymYrq______h_odX9qg1f___7q__9X_-h1f_5TBgwYM37__KOSur-_Ro0Pr_8_f_qDV_b___r__1f_6D___lFKlSpUu__8pmK_v7VAgwf______tNX9r______V__oP__-gQaPnwpm__yqDB__tUCD__QIEG___1f2qL____9X_-g____z5-__ymb__KoNX_-lQKl6VAgQav6_V__oNf___1f2qBX_____9-hKOf_8qgVJ0JRw4cOPLkqiQoESNGgVL0aFEjQoECJGjRoymDNm__ymTJkzZv3_____-3bt27du3Thw8efPnz58-fPnz58-fP___QIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECA",
           "type": "edit.tf"
       }    
   }
   

Adding Content using Markup

Content can be added directly to the JSON file using a very simple markup. For example consider the following frame definition.

   {
       "pid": {
           "page-no": 101,
           "frame-id": "a"
       },
       "visible": true,
       "frame-type": "information",
       "title": {
           "data": "[D]Welcome\r\n\r\n",
           "type": "markup"
       },
       "content": {
           "data": "[Y]Hello[C]Telstar[M]World",
           "type": "markup"
       }
   }
   

This frame uses markup in the title and the content, The title is specified as [D]ouble height and the three words used in the content are coloured yellow, cyan and magenta respectively.

The markup definitions are shown below.

   [R] alpha_red
   [G] alpha_green
   [Y] alpha_yellow
   [B] alpha_blue
   [M] alpha_magenta
   [C] alpha_cyan
   [W] alpha_white
   [F] flash
   [S] steady
   [N] normal_height
   [D] double_height
   

Raw Content

If the content type or title type is specified as raw, the data will be presented within TELSTAR without modification.

For example the previous frame in raw format would be defined as follows.

   {
       "pid": {
           "page-no": 101,
           "frame-id": "a"
       },
       "visible": true,
       "title": {
           "data": "\u001bMWelcome\r\n\r\n",
           "type": "raw"
       },
       "content": {
           "data": "\u001bCHello\u001bFTelstar\u001bEWorld",
           "type": "raw"
       }
   }
   

The unicode values specified for colour and double height are the values as specified in the videotex specification.


Complete Frame Description

The frame below is a standard information page from the TELSTAR system shown in its JSON format. It represents the first frame of page 899. Taking this page as an example, a description of the fields and their meaning is decribed below.

The full json schema can be found here.

    {
   	"pid": {
   		"page-no": 9,
   		"frame-id": "a"
       },
       "visible": true,
       "header-text": "",
       "cost": 0,
       "frame-type": "information",
       "redirect": {
           "page-no": 0,
           "frame-id": ""
       },
       "content": {
           "data": "https://edit.tf/#0:QIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgc4UCBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQICixYsWLFixYsWLFixYsWLFixYsWLFixYsWLFixYsWLFixYgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAxQIIs6PJnRYtKTOjoKkWnUQUIMeLTQIECBAgQIECBAgQIEDRAgp2adSLNQSZ0aegQIECBAgQIECBAgQIECBAgQIECBAgQNkCCPBqRa8GygpxaVaTDi00CBAgQIECBAgQIECBAgQIECBA4QIIc-dUgw6iCJFqQZMymgQIECBAgQIECBAgQIECBAgQIEDlAgmT46CfOQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQMECCZPjoJ8aMgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQICixYsWLFixYsWLFixYsWLFixYsWLFixYsWLFixYsWLFixYgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECAFUQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgBVAMUNMQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIAVQDFDTAlMPUQIECBAgQIECBAgQIECBAgQIECBAgQIECAFUAxQ0wJTD1A0EHSQIECBAgQIECBAgQIECBAgQIECBAgQIECANMCUw9QNBB0kCBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECAPUDQQdJAgQIECBAgQIECBAgQIECAosWLFixYsWLFixYsQIECAHSQIECAosWLFixYsWLFixYsWIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECBAgQIECA",
           "type": "edit.tf'
       },
       "title": {
           "data": "",
           "type": ""
       },
       "routing-table": [
           90,
           91,
           92,
           93,
           94,
           95,
           96,
           97,
           98,
           990,
           0
       ],
       "cursor": false,
       "connection": {
           "address": "",
           "mode": "",
           "port": 0
       },
       "author-id": "",
       "response-data": {
           "responses": null,
           "response-action": {
               "exec": "",
               "args": null,
               "post-action-frame": {
                   "page-no": 0,
                   "frame-id": 
               },
               "post-cancel-frame": {
                   "page-no": 0,
                   "frame-id": ""
               }
           }
       },
       "navmessage-select": "[B][n][Y]Select item or[W]*page# : [_+]",
       "navmessage-notfound": "[B][n][Y]Page not Found :[W]"
   }

pid

   page_no, frame_id

visible

     "visible": true,

header-text

     "header-text": "[Y]MICRONETn 800 (C)",

1. 1. cache-id

     "cache-id": "d4f71dbd-5cc0-4214-912e-e0340696291d",

1. 1. frame-type

The API supports the following frame types *initial*, *mainindex*, *information*, *exit*, *gateway*, *test*, *response*.

     "frame-type": "information",

1. 1. 1. initial

This frame type is used on the start page. The start page is specified within the *telstar.json* config file. The default page number is *99a*. Typically only one of these frames would exist within a system.

1. 1. 1. mainindex

This frame type is used on the main index page. The main index page is specified within the *telstar.json* config file. The default page number is *0a*. Only one of these frames should exist within a system.

1. 1. 1. information

This frame type is used for all normal content frames.

1. 1. 1. exit

This frame type is used for an exit page, any number of exit pages can be defined. When an exit page is rendered it will close the connection.

1. 1. 1. gateway

This page type is used to define a gateway page and is used in conjunction with the connection element (see below).

1. 1. 1. test

This page type indicates a test page and prevents navigation and system messages from being shown. this is typically used for frames that need to use the whole display such as 'test cards' etc.

1. 1. 1. response

This frame type is used in conjunction with the *response-fields element (see below) for response frames. See [Response Frames](response_frames.md).

1. 1. content

__Description to be added...__

     "content":

1. 1. title

__Description to be added...__

     "title": {
       "data": "",
       "type": ""
     },

1. 1. routing-table

__Description to be added...__

     "routing-table": [

       8000,
       8001,
       8002,
       8003,
       8004,
       8005,
       8006,
       8007,
       8008,
       8009,
       800
     ],

1. 1. cursor

This element determines whether a cursor is shown on the page. Typically a cursor would only be shown on response frames.

     "cursor": false,

1. 1. connection

This elements specifies the connection object used for gateway pages.

     "connection": {
       "address": "",
       "mode": "",
       "port": 0
     },

1. 1. 1. address and port

This represent the endpoint of the system being accessed.

1. 1. 1. mode

This determines how the system is accessed, the options are.

   viewdata
   full_duplex
   full_duplex_no_echo

1. 1. author-id

This is an optional field that can be used to indicate eith the author of the page or other source.

     "author-id": "editf-frame-generator",

1. 1. response-fields

These fields relate to the fields used in a *response-frame*, a response frame is a frame where a user is asked to enter information. The Telstar system weather page is one such frame where the user is asked to enter a city.

For information frames the value can be left blank as shown below or simply ommited altogether.

    "response-fields": [],

The following JSON snippet is taken from the TELSTAR system repsonse frame and shows a single field.

   "response-fields": [
     {
       "label": "City/Town : ",
       "vpos": 8,
       "hpos": 4,
       "required": true,
       "length": 16,
       "type": "alpha",
       "auto_submit": true,
       "value": "",
       "valid": false,
       "password": false
     }
   ]

1. 1. 1. label

The *label* element will be displayed alongside the data entry area.

1. 1. 1. vpos, hpos

These specify where the field is displayed on the page.

1. 1. 1. required

If set to *true*, it will not be possible to continue past the page until some data is entered.

1. 1. 1. length

Refers to the length of the data field. See *auto_submit* below

1. 1. 1. type

This element defines what characters can be entered into the field the options are

• numeric*, *alpha* and *alphanumeric*.

1. 1. 1. auto_submit

If, when enter data into the field, a user reaches the *length* (see above), the page will auto submit if this value is set to true.

1. 1. 1. value

The value will contain the entered data when the response frame is processed. See plugins.

1. 1. 1. valid

1. 1. 1. password

Set to tru will ensure that the entered data is not echoed back to the user. Asterisks are sent instead.

1. 1. 1. navmsg-forecolour, navmsg-backcolour and navmsg-highlight

These elements represent the colours of the navigation message on ro 23 of the frame, these are optional values and will default to Yellow, Blue and White respectively.

   "navmsg-forecolour": "yellow",
   "navmsg-backcolour": "blue",
   "navmsg-highlight": "white",