Terminal :computer:

Terminal service provides an interface to run terminal commands for terminal-enabled uAPI credentials.

PCC Emulation

You can use Terminal service to run commands on behalf of your own PCC or to use emulatePcc option from auth to run commands on behalf of other PCC using your own Service bureau.

In uapi terminals are not linked to the specific PCC and identified only by tokens. That’s why, if the emulatePcc option is passed, we run SEM command behind the scene to provide emulation for specific PCC.

Though you may still send SEM commands to the terminal on your own, in order to not messthings up, we highly recommend you to use several terminal instances for several PCC emulations.

See advanced emulation example to get an example on how to use emulation.

uAPI error handling

In case you want to handle some specific errors from uAPI, you can provde uapiErrorHandler function in options.

Function should return response from retried command or any other command.

Footprint of the functions should be as follows:

async (
  executeCommandWithRetry,
  { command, error: err }
) => {
  // your code goes here
  // response is an array of strings (lines of terminal response)
  return response;
}

Session closing

Be aware to close the session after all your manipulations with the terminal.

Session closing takes the current token and sends a request to terminate the session, see close_session method.

API

TerminalService

.executeCommand(command, options)

Executes a command in terminal and returns its terminal response

Returns: Promise that returns terminal command response in String format

Param Type Description
command String String representation of the command you want to execute
options Object Optional command execution options.

Options

Param Type Description
stopMD (screens) => boolean Function which gets all previous screens concatenated and detects if more MD command needed.
sleepInterval Number Minimum delay in milliseconds from the last successful full terminal response to the next command send.

stopMD must be passed inside options; passing it directly as the second argument is not supported.

.executeStatelessCommandWhenIdle(command, options)

Executes a stateless command when terminal is idle and returns its terminal response.

If terminal is busy, command is added to the stateless commands queue and executed after the current command and previously queued stateless commands are finished. Queued commands are executed one by one in FIFO order. If terminal is idle, regular executeCommand calls execute before queued stateless commands.

This method is promise based. Every caller receives the result or error from its own command execution. If one queued command fails, later queued commands are still executed. If the active command fails before the queue is drained, queued stateless commands are skipped and rejected with the same terminal error.

Stateless means command is independent of terminal context, such as an open booking, fare search, or other GDS working state. This method does not detect or enforce statelessness; caller is responsible for using it only for commands safe in any terminal context.

Returns: Promise that returns terminal command response in String format

Param Type Description
command String String representation of the stateless command you want to execute
options Object Optional command execution options.

Options

Param Type Description
stopMD (screens) => boolean Function which gets all previous screens concatenated and detects if more MD command needed.
sleepInterval Number Minimum delay in milliseconds from the last successful full terminal response to the next command send. 
await TerminalService.executeCommand('TE', {
  stopMD: (screens) => screens.includes('END OF DISPLAY'),
});

await TerminalService.executeStatelessCommandWhenIdle('.CDIEV', {
  sleepInterval: 1000,
});

.closeSession()

When you have finished command execution it’s necessary to close terminal connection to free up space in the terminal pool. Takes no parameters

Returns: Promise which fullfills with true if terminal was succesfully closed

.getToken()

Use this method to resolve token. If token is resolved after executeCommand it takes no time for resolving.
Takes no parameters

Returns: Promise<String>