$this->EE->api_channel_entries->data (via entry_submission_ready hook) not working on front end

Question

I have the following entry_submission_ready method in an extension to update a field's data. This works fine when saving an entry in the control panel, but it doesn't change the field value on the front end using Channel Form. The function is called, because I can output $data to the screen.

function entry_submission_ready($meta, $data, $autosave)
{
    $data['field_id_281'] = 'Test';

    if(isset($this->EE->api_sc_channel_entries))
    {
        $this->EE->api_sc_channel_entries->data = $data;                
    }
    else
    {
        $this->EE->api_channel_entries->data = $data;
    }
}

It seems $this->EE->api_channel_entries->data is empty on the front end, but is used in the control panel. So what would one use to save the data on the front end using Channel Form?

Answer 1

I have got it to work using a second hook, channel_form_submit_entry_start

Using channel_form_submit_entry_start I can manipulate the $_POST array directly, then this saves. Seems wrong I should manipulate $_POST, and also a shame I have to have a second method to do the same as the entry_submission_ready (difficult to combine as I am using different arrays), but at least this works:

function channel_form_submit_entry_start($obj)
{
    $_POST['field_id_281'] = 'Test';
}

Answer 2

I don't have experience with the channel form hooks, but I have implemented something similar using the the entry_submission_start hook, which should get fired on an entry submission regardless of whether it comes from the front-end or backend.

You can access and modify the channel data before it gets inserted by accessing $this->EE->api_channel_entries->data by reference.

Something like so would set field_id_281 to have the value of foo regardless of what was submitted in the entry form:

public function entry_submission_start( $channel_id = 0, $autosave = FALSE )
{   
    // access our data by referece
    $this->data =& $this->EE->api_channel_entries->data;
    $this->data['field_id_281'] = 'foo';
}

You'd replace $this->EE with ee() on EE version 2.7+