hello, Rory!

how can I help you today?

Hey Mark!

To be honest, I just came across your Busy coders book recently, and seen that you offered Q+A sessions at allowed times - so I had been meaning to try it some time - come in see the format, rules etc

ah

mostly, people swing by when they have specific questions

as a result, the room is rarely crowded

So - the format is completely open ?

well, it'd be nice if the questions were on Android app development

It's a great concept - awesome support mechanism

versus, say, the proper way to prepare BBQ

:-)

I'll defs make use of it

you can see past chat transcripts at https://commonsware.com/office-hours/

How long have you been providing this?

chats specifically since late 2009

the book debuted in the summer of 2008

Very cool

Ok - I'm sure I have a ton of questions ...

the one thing to bear in mind is that these chats are semi-public

What is your preferred networking lib/framework?

Yeah - that's fine

mostly, I use the Square libraries: OkHttp, Retrofit, Picasso

I'm working on a project and am trying to decide between Volley and Retro

Retrofit seems to the more widely used - yet Volley is the (un)official lib..

yeah, the key there is "(un)official

(give or take a quotation mark)

Haha...yeah

it's had a very strange life

it only was published as an artifact earlier this year

prior to that, you had to clone a git repo and add it manually

Yeah... why was that ...

Strange indeed

That Google didn't put some resources behind it

I have never fully understood what the story is there

Make it the defect Android networking lib

and that's one of the reasons I prefer the Square libraries

there's a clearer support structure (issue tracker, versioning, etc.)

Yeah - Square do great work

Oh actually ... I would like to ask you something

Sort of specific

go ahead -- worst-case, I can't answer the question

A project I am working ... I need to implement a queue system - similar to a shop queue - user takes a place in queue - is served FIFO

I am using Firebase as backend

However I am researching the manner in which to implement this

well, I have never used Firebase, so I cannot comment on anything tied to its APIs

Firebase files structured in JSON data

Oh right

Ok may I ask you this then ... how would you approach implementing such a FIFO data structure using SQL instead... out of curiosity ?

SQLite*

off the cuff? probably use a timestamp to determine the ordering

Yeah off the top of your head...

Eager to pick your brain a little

...though not too much :)

beyond that, the rest of the fields would be dependent on what your queue needed to track and stuff

the bigger issue with something like a queue is ensuring items on the queue are processed exactly once

that gets tough when you start thinking about exceptions, multiple threads/processes pulling from the queue, etc.

so, really, I would try to find an existing robust queue implementation

I assume, given that you mentioned Firebase, that the queue is effectively on the server, with one queue processing requests from some/all app users?

Literally - Single queue - Maximum 6 points of entry - User takes ticket - User placed in queue - Arbitrary time passes - User contacted via message - If User responds - user popped from queue - If user does not respond - Set time passes - User removed from queue

It's probably much more complicated than I had anticipated ...

but, again, this is a queue that is implemented on the server side?

versus some in-app job queue?

It wouldn't necessarily have to be implemented at server ... could just as easily be in-app, as long as it's permitted

*persisted

OK, so each user has his or her own queue?

Yeah

Think of it like this

There are 6 barbers

Each has a queue

Customer takes ticket - placed in queue

Customer process FIFO

but that FIFO is for the specific barber whose queue the customer joined?

The reason i was thinking of using Firebase was because of the easy sync function that it provides

Yes

OTOH, it requires an active network connection

Each Barber has a FIFO queue

in your earlier explanation, you wrote "User contacted via message" -- what do you mean, specifically?

a Notification? SMS? email? candygram? something else?

Ah sorry - I should have explained

Yes - an SMS

*a sms

When their seat is ready

well, that implies a server, as an app cannot readily send an SMS to itself

(and, even if it could, that would be... odd)

Ive simplified it - The user must initially create a profile with name, contact details etc

So - yeah - a server would be needed

OK, so, then, rolling *all* the way back to how would I do it: I would see if somebody has already implemented a FIFO queue for Firebase

personally, I avoid SSSaaS (Server-Side Stuff as a Service), so I'd be looking at using existing work queues, mostly in the Ruby space, as that's what I use for server-side development

Yeah

Time to maybe pick up Ruby ...

message queues, with Ruby bindings, are a dime a dozen

but, that's not Firebase

my overarching theme is: don't reinvent the wheel, particularly when the wheel might get tricky to build

now, it's entirely possible that you're on your own for a Firebase-backed FIFO queue

Yeah - My thoughts were that Firebase abstracted away the complexity to a nice set of interface methods

though, there's https://github.com/firebase/firebase-queue

Although most likely inherently restrictive ...

My project is probably too intricate to depend on a framework, like Firebase

and, other than this server is going to be used by an Android app, it's a bit far afield from what I can help with

No Mark - appreciate your time and advice dude

How often do you run 'Office Hours'?

usually three hours a week

staggered at different times of the day, to try to offer at least one that's reasonably convenient for any time zone

occasionally, due to travel, I am unavailable

That's really great - fantastic support

Can you tell about about any interesting Android projects youve worked on?

not really, thanks to non-disclosure agreements

Yeah - thought that

Ive just finished working on a major commercial banking application - worked with some very talented engineers - I've been working on Android for 3 years now ... still have a long long way to go ...

I'd be interested in finding out more about the private training you offer... is the target audience large corporate groups or, individuals also?

mostly, it is for groups

I used to work with training firms offering public training, where individuals could sign up

I haven't done that in a couple of years

that particular model has been suffering at the hands of MOOCs and stuff

MOOCs?

Udacity and kin

Ahh

Yeah - i signed up to their advanced course ...

Bit too simplistic...

yeah, advanced Android app training never sold well

I never cared for it, just because it tended to feel like "well, here's another week's worth of random topics"

Just need on-th-job-experience I guess

there was no story behind it, the way we had with introductory training

Yeah I seen that you stopped the advanced

beyond on-the-job stuff, keep tabs on conferences that post videos of their talks

the video quality tends to vary

but for the ones that get decent results, you can get a ton of material, usually for free

I suppose once an approximation of all the topics are covered - it's a matter for the individual to get into the intricacies themselves

Could you name some examples to look out for ..

I'm always on the look out in any case ..

in terms of conferences with videos?

or are you referring to something else?

yeah

DroidCon etc?

some droidcon events publish videos

droidcon UK used to, not sure if they still do

droidcon NYC will do it for their conference coming up in a month

Google I|O and the Android Developer Summit that Google held last year

Denver

er, Denver's conference (360 DevCon? I forget the name) from earlier this year

the Android Summit that Capital One just hosted will have videos up sometime

there are a few Android-specific conference lists, such as http://androidweekly.net/conferences and https://androidstudygroup.github.io/conferences/

keep tabs on some of those to see if they publish videos sometime after the event

Nice

Thanks MArk

that's a wrap for today's chat

the transcript will be posted to https://commonsware.com/office-hours/ shortly

the next chat is tomorrow at 7:30pm US Eastern

have a pleasant day!

Nice chatting Mark

Thanks