[SalesForce] How to call a batch from a trigger

I think you can use something like following:

global class Dummy_Schedulable_Class implements Schedulable{

    global String dailyCronExpression = '0 0 13 * * ?';
    global String monthlyCronExpression = '0 0 13 1 * ?';
    global String weeklyCronExpression = '0 0 13 ? * 1';

    global void execute(SchedulableContext SC) {

    }

    public static void scheduleThis(String argPass){
        String cronExp;
        if ( 'daily'.equals( argPass ) ) {
            cronExp = dailyCronExpression;
        } else if ( 'monthly'.equals( argPass ) ) {
            cronExp = monthlyCronExpression;
        } else if ( 'weekly'.equals( argPass ) ) {
            cronExp = weeklyCronExpression;
        }
        System.assertNotEquals(null, cronExp, 'Please pass "daily" "monthly" or "weekly" argument to this method.');
        System.schedule('test', cronExp, new Dummy_Schedulable_Class());
    }

}

and then call

Dummy_Schedulable_Class.scheduleThis('monthly');

or

Dummy_Schedulable_Class.scheduleThis('daily');

or

Dummy_Schedulable_Class.scheduleThis('weekly');

String constant dailyCronExpression = '0 0 13 * * ?' means 'every day at 1 p.m.' String constant dailyCronExpression = '0 0 13 1 * ?' means 'every first day of month at 1 p.m.' String constant dailyCronExpression = '0 0 13 * * ?' means 'every first day of week at 1 p.m.'

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Definitely you can use an HTTP callout as an escape mechanism. But this is pretty naughty. You'll need a Remote Site Setting and a Session ID and a global class etc etc etc (red flags, alarm bells).

May I humbly recommend the use of System.Queueable call instead of @Future. You can create a class that is constructed with any kind of argument that you want to hand in, like so:

public class DeferredHandler implements System.Queueable
{

    private Map<String,String> key2val;

    public DeferredHandler(Map<String,String> key2val) {
        this.key2val = key2val;
    }

    public void execute(System.QueueableContext objContext)
    {
        //do your @Future stuff here with this.key2val
    }

}

And invoke him from inside your batch like this:

//defer stuff
System.Queueable job = new DeferredHandler(key2val);
System.enqueueJob(job);

There is some literature about this in the docs and Josh Kaplan's awesome Queueable blog post.