SAP HANA on the moon (with Lua)

This post was originally posted on SAP HANA on the moon (with Lua).

Lua is a lightweight multi-paradigm programming language designed as a scripting language with extensible semantics as a primary goal. Lua is cross-platform since it is written in ANSI C, and has a relatively simple C API.

If you wonder about the title…well…Lua means Moon in Portuguese -;)

Lua is very powerful but easy to learn and use. If you already know Python or Ruby, you will be just fine…

Before we move on…I want to share a little joke…which is not specific to Lua only…but still funny -;)

So…no example or demonstration would be complete if we didn’t hook it up with SAP HANA, right? So…let’s go and do it -;)

First, we need to create a Calculation View and call it “FLIGHTS_BY_CARRIER”. It will be composed of two tables, SCARR and SFLIGHT.

First, we need to create a Join object and link the table by MANDT and CARRID. From here select the following fields as output MANDT, CARRID, CARRNAME, PRICE and CURRENCY.

Then create an Aggregation object selecting the fields CARRNAME, PRICE (As Aggregated Column) and CURRENCY. Filter the CURRENCY field by ‘USD’.

Then create a Projection object and select only PRICE and CARRNAME.

On the Semantics object make sure to select “CROSS CLIENT” as the Default Client.

Now, switch to the SAP HANA Development View and create a new repository. Call it “Flights”.

Create a new “XS Engine” project and call it “Flights” as well. Link it to the “Flights” repository.

Create an empty “.xsapp” file.

Create a file called “.xsaccess” with the following code.

.xsaccess
{ "exposed" : true, "authentication" : [ { "method" : "Basic" } ] }

Finally create a file called “flights.xsodata” with the following code

flights.xodata
service { "Blag/FLIGHTS_BY_CARRIER.calculationview" as "FLIGHTS" keys generate local "Id"; }

Activate your project and launch it on your browser, you should see something like this…

The SAP HANA part is done…so we can move into the Lua part…

Before we continue…I will recommend you to install a couple of things…if you’re on Linux…install this…

sudo apt-get install lua5.2

And then follow the instructions to install LuaRocks a package manager for Lua…

Install the following packages…

sudo luarocks install luasec
sudo luarocks install luajson
sudo luarocks install luasocket

To code for Lua, you can use any editor that you like…Copy and paste the following code…

Lua_HANA.lua
http = require("socket.http") mime = require("mime") ltn12 = require("ltn12") json = require("json") h = {Authorization = "Basic " .. (mime.b64("SYSTEM:YourPassword")), ["Content-Type"] = "application/json", ["content-length"] = jsonsize } local resp ={} ok, code, headers = http.request{url = "http://YourServer:8000/Flights/flights.xsodata/FLIGHTS?$format=json", redirect = true, method = "GET", headers = h, source = source, sink = ltn12.sink.table(resp)} local dec = json.decode(resp[1]) local d = dec["d"]["results"] for i = 1, #d do io.write(d[i]["CARRNAME"]," : ",d[i]["PRICE"], "\n") end print("")

Doing this integration with Lua was quick and easy…Lua is a really nice language with some really nice features that can’t be found on other languages…

Greetings,

Blag.
Development Culture.

SAP HANA in the talons of Falcon

This post was originally posted on SAP HANA in the talons of Falcon.

Falcon is an Open Source, multi-paradigm programming language. It supports procedural, object-oriented, prototype-based, functional, tabular and message passing. It first appeared 12 years ago…so not a new and fresh language. It was the default scripting language for the now disappeared Auroraux operating system.

Falcon is pretty awesome and has some features that other programming languages would kill to have -:)

So…no example or demonstration would be complete if we didn’t hook it up with SAP HANA, right? So…let’s go and do it -;)

First, we need to create a Calculation View and call it “FLIGHTS_BY_CARRIER”. It will be composed of two tables, SCARR and SFLIGHT.

First, we need to create a Join object and link the table by MANDT and CARRID. From here select the following fields as output MANDT, CARRID, CARRNAME, PRICE and CURRENCY.

Then create an Aggregation object selecting the fields CARRNAME, PRICE (As Aggregated Column) and CURRENCY. Filter the CURRENCY field by ‘USD’.

Then create a Projection object and select only PRICE and CARRNAME.

On the Semantics object make sure to select “CROSS CLIENT” as the Default Client.

Now, switch to the SAP HANA Development View and create a new repository. Call it “Flights”.

Create a new “XS Engine” project and call it “Flights” as well. Link it to the “Flights” repository.

Create an empty “.xsapp” file.

Create a file called “.xsaccess” with the following code.

.xsaccess
{ "exposed" : true, "authentication" : [ { "method" : "Basic" } ] }

Finally create a file called “flights.xsodata” with the following code

flights.xodata
service { "Blag/FLIGHTS_BY_CARRIER.calculationview" as "FLIGHTS" keys generate local "Id"; }

Activate your project and launch it on your browser, you should see something like this…

The SAP HANA part is done…so we can move into the Falcon part…

Falcon should be bundled already in every Linux based system…and I’m sure you haven’t even noticed it -;)

Anyway…you can grab it from Falcon Releases...

Now…as I’m still a Falcon newbie…I’m not sure if we really need this…but just in case…install it…

apt-get install falconpl-curl

It’s the curl binding for Falcon…

Grab your favorite editor and copy and paste the following code…

falcon_hana.fal
import from curl import from json h = curl.Handle("http://YourServer:8000/Flights/flights.xsodata/FLIGHTS?$format=json") auth = "Authorization:Basic " + Base64.encode("SYSTEM:YourPassword") headers = [auth] h.setOption(curl.OPT.HTTPHEADER,headers) h.setOption(curl.OPT.SSL_VERIFYPEER,false) data = h.setOutString().exec().getData() try raw = json.JSONdecode( data ) catch printl( "Can't decode the string" ) end d = raw["d"] results = d["results"] for Index in [0:results.len()] print(results[Index]["CARRNAME"]) print(" : ") printl(results[Index]["PRICE"]) end

To execute it…simply open a terminal session and go to source code folder and type

Falcon falcon_hana.fal 

I have to admit that this wasn’t easy at first…the Falcon documentation doesn’t talk about curl…so I need to check the source code on GitHub…make a lot of testing…until I finally could get it to work…the json part on the other hand was extremely easy -:D

Greetings,

Blag.
Development Culture.

LED is my new Hello World - Kotlin Time

Yep...I'm aware that there must be a lot of more efficient and short ways to do this...but then again...my purpose with this is to have the same base code for all the programming languages that I learn...

Usually I write this code after a couple of days of learning the language...so in no way I can be aware of all the crazy and optimized features...

This code is just for fun and for me...a really good way to introduce the syntax of a language in a very friendly way...

So...here's is Kotlin -:)

LEDNumbers.kt
package LEDNumbers fun main(args: Array<String>) { if (args.size == 0) { println("Please provide a number...") return } val NumList:List<String> = args[0].split("") val Leds = mapOf("0" to listOf(" _ ", "| | ", "|_| "), "1" to listOf(" ", "| ", "| "), "2" to listOf(" _ "," _| ","|_ "), "3" to listOf("_ ","_| ","_| "), "4" to listOf(" ","|_| "," | "), "5" to listOf(" _ ","|_ "," _| "), "6" to listOf(" _ ","|_ ","|_| "), "7" to listOf("_ "," | "," | "), "8" to listOf(" _ ","|_| ","|_| "), "9" to listOf(" _ ","|_| "," _| ")) for(i in 0..2){ for(j in 1..NumList.size - 2){ print(Leds[NumList[j]]!![i]) } print("\n") } }

The result will like this -;)

Greetings,

Blag.
Development Culture.

My first post on Kotlin

As always...I was looking for another programming language to learn...I was thinking about Scala or Rust...but then I got this comment on Twitter -;)

So sure...why not Kotlin? -:)

So what's Kotlin all about? Well...Kotlin is a Statically typed programming language for the JVM, Android and the browser. It's also 100% interoperable with Java.

While this is not a mind bending language...meaning that you can get used to it pretty fast...it has some nice and cool feature that are worthy to explore...

As always...being this my first post...here's the Fibonacci list example...

fibonacci.kt
package Fibonacci fun fib(num: Int, a: Int, b: Int): String { var result: String = "" if(a > 0 && num > 1) { result = result + (a+b) + " " + fib(num-1,a+b,a) }else if (a == 0) { result = a.toString() + " " + b + " " + (a+b) + " " + fib(num-1,a+b,b) } return result } fun main(args: Array<String>) { if (args.size == 0) { println("Please provide a number...") return } val num: Int = args[0].toInt() println(fib(num,0,1)) }

And the screenshot for sure -:)

Will post the LED_Numbers app really soon...so stay tuned -;)

Greetings,

Blag.
Development Culture.

Getting functional with SAP HANA and Erlang

This post was originally posted on Getting functional with SAP HANA and Erlang.

Erlang is a general-purpose concurrent, garbage-collected programming language and runtime system. And it’s also Functional, with eager evaluation, single assignment and dynamic typing. Did I forget to mention that it’s also distributed, concurrent and fault-tolerant.

Big description, huh? Well…Erlang has been around for the almost past 30 years…

So…no example or demonstration would be complete if we didn’t hook it up with SAP HANA, right? So…let’s go and do it -;)

First, we need to create a Calculation View and call it “FLIGHTS_BY_CARRIER”. It will be composed of two tables, SCARR and SFLIGHT.

First, we need to create a Join object and link the table by MANDT and CARRID. From here select the following fields as output MANDT, CARRID, CARRNAME, PRICE and CURRENCY.

Then create an Aggregation object selecting the fields CARRNAME, PRICE (As Aggregated Column) and CURRENCY. Filter the CURRENCY field by ‘USD’.

Then create a Projection object and select only PRICE and CARRNAME.

On the Semantics object make sure to select “CROSS CLIENT” as the Default Client.

Now, switch to the SAP HANA Development View and create a new repository. Call it “Flights”.

Create a new “XS Engine” project and call it “Flights” as well. Link it to the “Flights” repository.

Create an empty “.xsapp” file.

Create a file called “.xsaccess” with the following code.

.xsaccess
{ "exposed" : true, "authentication" : [ { "method" : "Basic" } ] }

Finally create a file called “flights.xsodata” with the following code

flights.xodata
service { "Blag/FLIGHTS_BY_CARRIER.calculationview" as "FLIGHTS" keys generate local "Id"; }

Activate your project and launch it on your browser, you should see something like this…

The SAP HANA part is done…so we can move into the Erlang part…

Erlang, as opposed to many other languages, doesn’t have a Package Manager, so we need to only download the package that we want and compile it -;)

To code for Erlang I use one of the most awesome editors I have ever found…Geany. It comes almost pre-configured to handle a lot of programming languages, so you will be ready to code for Erlang.

We need to download mochijson2.erl and save it on our project folder, then we can simply compile it by calling

erlc mochijson2.erl

From the terminal or press the “Compile the current file” button. First one on the image.

With that, we should be more than ready to start coding -:) Copy and paste the following code…

Erlang_HANA.erl
-module(erlang_HANA). -export([getOData/0,showInfo/5]). showInfo(Carriers, Prices, Acc, Len, Ctr) when Ctr =< Len -> showInfo(Carriers, Prices, Acc ++ [binary_to_list(lists:nth(Ctr,Carriers))] ++ [": "] ++ [binary_to_list(lists:nth(Ctr,Prices))] ++ ["\n"], Len, Ctr + 1); showInfo(_, _, Acc, Len, Ctr) when Ctr > Len -> io:format("~s",[Acc]). getOData() -> inets:start(), Response = httpc:request(get, {"http://54.65.196.224:8000/Flights/flights.xsodata/FLIGHTS?$format=json", [{"Authorization", "Basic " ++ base64:encode_to_string("SYSTEM:Blag1977")}]}, [], []), Flights = mochijson2:decode(response_body(Response)), {struct, JsonData} = Flights, {struct, D} = proplists:get_value(<<"d">>, JsonData), Results = proplists:get_value(<<"results">>, D), Carriers = [proplists:get_value(<<"CARRNAME">>, S) || {struct, S} <- Results], Prices = [proplists:get_value(<<"PRICE">>, S) || {struct, S} <- Results], showInfo(Carriers, Prices, "", length(Carriers), 1). response_body({ok, { _, _, Body}}) -> Body.

Save your file and press the “Run or view the current file” button. The last one from the image that displays two engines.

You will need to use the format “name_of_file:method()” to load it into memory and execute it -;)

Greetings,

Blag.

Development Culture.

SCN Vanity App

This post was originally posted on SCN Vanity App.

This one goes out to my friend and colleague Aaron Williams who gave the idea for this -;)

For this one, we're going to use Python and some nice libraries...

Libraries
pip install pandas #For Data Analysis and Data Frames pip install mechanize #Headless Web Browser pip install beatifulsoup4 #For Web Scrapping

Of course...we're going to use some Regular Expressions as well...but that's already included in Python :)

So, the basic idea is that we need to log into SCN using our Username and Password and then read the first page of our "content" folder only for blog posts...then we can continue reading the following pages by using a parameter that will load the next 20 blogs...

Now...and before you say something -:P This works (at least for me) only for the first 10 pages...because after that the HTML seems to be automatically generated...so there's nothing to get more data from -:( or maybe my blogs come from a long time ago...my first blog ever on SCN was written on February 17, 2006 Tasting the mix of PHP and SAP...

Anyway...let's see the source code -:D

SCN_Vanity_App.py
#coding= utf8 USR = 'YourUser' PWD = 'YourPassword' import sys import re import mechanize from BeautifulSoup import BeautifulSoup import pandas as pd reload(sys) sys.setdefaultencoding("iso-8859-1") cookies = mechanize.CookieJar() br = mechanize.Browser() br.set_cookiejar(cookies) br.set_handle_robots(False) res = br.open("http://scn.sap.com/login.jspa") br.select_form(nr=0) br["j_username"] = USR br["j_password"] = PWD br.submit() br.select_form(nr=0) res = br.submit() result = res.read() author = re.search("username: \'.*",result) author = re.sub('username: \'|\'|\,','',author.group(0)) displayname = re.search("displayName: \'.*",result) displayname = re.sub('displayName: \'|\'|\,','',displayname.group(0)) j = 0 df = pd.DataFrame() while(1==1): try: link = "http://scn.sap.com/people/%s/content?filterID="\ "contentstatus[published]~objecttype~objecttype[blogpost]" %(author) if(j>0): link = "http://scn.sap.com/people/%s/content?filterID="\ "contentstatus[published]~objecttype~objecttype[blogpost]&start=%j" %(author,str(j)) j += 20 res = br.open(link) Titles = [] Likes = [] Bookmarks = [] Comments = [] Views = [] soup = BeautifulSoup(res.read()) list_items = [list_item for list_item in soup.findAll('td',{'class':'j-td-title'})] if(len(list_items) == 0): break; for i in range(0, len(list_items)): title = re.search('[^<>]+(?=<)',str(list_items[i])) Titles.append(title.group(0)) list_items = [list_item for list_item in soup.findAll('a',{'class':'j-meta-number'})] for i in range(0, len(list_items), 2): like = re.sub('<[^>]+>|in.*','',str(list_items[i])) bookmark = re.sub('<[^>]+>|in.*','',str(list_items[i+1])) Likes.append(int(like)) Bookmarks.append(int(bookmark)) list_items = [list_item for list_item in soup.findAll('span',{'title':'Replies'})] for i in range(0, len(list_items)): comment = re.sub('<[^>]+>|in.*','',str(list_items[i])) Comments.append(int(comment)) list_items = [list_item for list_item in soup.findAll('span',{'title':'Views'})] for i in range(0, len(list_items)): views = re.sub('<[^>]+>|in.*','',str(list_items[i])) Views.append(int(views)) for i in range(0, len(Titles)): df = df.append({'Title': Titles[i], 'Likes': Likes[i], 'Bookmarks': Bookmarks[i], 'Comments': Comments[i], 'Views': Views[i]}, ignore_index=True) except: break print("Welcome " + displayname + "\n") sum_row = df[["Views"]].sum() print("Total number of Views" + " ==> " + str(sum_row.values[0])) sum_row = df[["Comments"]].sum() print("Total number of Comments" + " ==> " + str(sum_row.values[0])) sum_row = df[["Bookmarks"]].sum() print("Total number of Bookmarks" + " ==> " + str(sum_row.values[0])) sum_row = df[["Likes"]].sum() print("Total number of Likes" + " ==> " + str(sum_row.values[0])) print("\nTop 3 Blogs with most Views") print("---------------------------") df = df.sort_values(by=['Views'],ascending=[False]) for i in range(0, 3): print(df.iloc[[i]]['Title'].values[0] + " ==> " + str(df.iloc[[i]]['Views'].values[0])) print("\nTop 3 Blogs with most Comments") print("---------------------------") df = df.sort_values(by=['Comments'],ascending=[False]) for i in range(0, 3): print(df.iloc[[i]]['Title'].values[0] + " ==> " + str(df.iloc[[i]]['Comments'].values[0])) print("\nTop 3 Blogs with most Bookmarks") print("---------------------------") df = df.sort_values(by=['Bookmarks'],ascending=[False]) for i in range(0, 3): print(df.iloc[[i]]['Title'].values[0] + " ==> " + str(df.iloc[[i]]['Bookmarks'].values[0])) print("\nTop 3 Blogs with most Bookmarks") print("---------------------------") df = df.sort_values(by=['Likes'],ascending=[False]) for i in range(0, 3): print(df.iloc[[i]]['Title'].values[0] + " ==> " + str(df.iloc[[i]]['Likes'].values[0]))

If we run this code, then we're going to have a nice report like this one -;)

Of course...it would look better with a nicer UI...but that's not my forte -:(  So...if anyone wants to pick the project and improve it...I would really appreciate it -;)

Greetings,

Blag.
Development Culture.

Ada and HANA playing together

This post was originally posted on Ada and HANA playing together.

Ada is a structured, statically typed, imperative, wide-spectrum and object-oriented programming language, extended from Pascal and other languages.

It was originally developed for the United States Department of Defense. And it was named after Ada Lovelace (1815-1852), who was the first computer programmer.

Ada is a language that simply would not allow you to fail…as it have mechanisms for compile and execution time checks…getting rid of most of the bugs that your application could ever produce…

So…no example or demonstration would be complete if we didn’t hook it up with SAP HANA, right? So…let’s go and do it -;)

First, we need to create a Calculation View and call it “FLIGHTS_BY_CARRIER”. It will be composed of two tables, SCARR and SFLIGHT.

First, we need to create a Join object and link the table by MANDT and CARRID. From here select the following fields as output MANDT, CARRID, CARRNAME, PRICE and CURRENCY.

Then create an Aggregation object selecting the fields CARRNAME, PRICE (As Aggregated Column) and CURRENCY. Filter the CURRENCY field by ‘USD’.

Then create a Projection object and select only PRICE and CARRNAME.

On the Semantics object make sure to select “CROSS CLIENT” as the Default Client.

Now, switch to the SAP HANA Development View and create a new repository. Call it “Flights”.

Create a new “XS Engine” project and call it “Flights” as well. Link it to the “Flights” repository.

Create an empty “.xsapp” file.

Create a file called “.xsaccess” with the following code.

.xsaccess
{ "exposed" : true, "authentication" : [ { "method" : "Basic" } ] }

Finally create a file called “flights.xsodata” with the following code

flights.xodata
service { "Blag/FLIGHTS_BY_CARRIER.calculationview" as "FLIGHTS" keys generate local "Id"; }

Activate your project and launch it on your browser, you should see something like this…

The SAP HANA part is done…so we can move into the Ada part…

Ada comes installed in most Linux-based distros…but the version can be old…so it’s better to download and install a more recent version…so please just do this on a terminal session…

sudo apt-get install gnat
sudo apt-get install libaws-bin libaws3.2.0-dev

To install both Ada and AWS (Nope…not that one…but Ada Web Server)…

Also, we will need to download and install XML/Ada

tar zxvf xmlada-gpl-4.3-src.tgz
cd xmlada-4.3-src/
./configure --prefix=/usr/gnat
PROCESSORS=4 make all
make docs
make install

Then, you will need to update your .bashrc file in order to have the right paths…

PATH=/usr/gnat/lib/gnat:$PATH
export PATH
GPR_PROJECT_PATH=/usr/gnat/lib/gnat:$GPR_PROJECT_PATH
export GPR_PROJECT_PATH

ADA_PROJECT_PATH=$ADA_PROJECT_PATH:/usr/gnat/lib/gnat
export ADA_PROJECT_PATH
ADA_OBJECTS_PATH=$ADA_OBJECTS_PATH:/usr/gnat/lib/gnat
export ADA_OBJECTS_PATH
ADA_INCLUDE_PATH=$ADA_INCLUDE_PATH:/usr/gnat/lib/gnat
export ADA_INCLUDE_PATH

Then create a file called ada_hana.adb on your favorite editor and copy the following code

ada_hana.adb
with Ada.Text_IO; use Ada.Text_IO; with AWS.Client; with AWS.Response; with Input_Sources.Strings; with Unicode.CES.Utf8; with Ada.Strings.Unbounded; use Ada.Strings.Unbounded; with Sax.Readers; use Sax.Readers; with DOM.Readers; use DOM.Readers; with DOM.Core; use DOM.Core; with DOM.Core.Documents; use DOM.Core.Documents; with DOM.Core.Nodes; use DOM.Core.Nodes; with DOM.Core.Attrs; use DOM.Core.Attrs; procedure Ada_Hana is Flights : Unbounded_String; Input : Input_Sources.Strings.String_Input; Reader : Tree_Reader; Doc : Document; C_List : Node_List; P_List : Node_List; C_N : Node; P_N : Node; begin Flights := AWS.Response.Message_Body (AWS.Client.Get (URL=>"http://YourServer:8000/Flights/flights.xsodata/FLIGHTS", User => "SYSTEM", Pwd => "YourPassword")); Input_Sources.Strings.Open (To_String(Flights), Unicode.CES.Utf8.Utf8_Encoding, Input); DOM.Readers.Parse (Reader, Input); Doc := Get_Tree (Reader); C_List := Get_Elements_By_Tag_Name (Doc, "d:CARRNAME"); P_List := Get_Elements_By_Tag_Name (Doc, "d:PRICE"); for Index in 1 .. Length (C_List) loop C_N := Item (C_List, Index - 1); P_N := Item (P_List, Index - 1); Put_Line (Node_Value(First_Child(C_N)) & ": " & Node_Value(First_Child(P_N))); end loop; Free (C_List); Free (P_List); Free (Reader); end Ada_Hana;

To compile this application we need to create another file…called compile_ada_hana.gpr

compile_ada_hana.gpr
with "aws"; project Compile_Ada_HANA is for Main use ("ada_hana.adb"); end Compile_Ada_HANA;

And run it like this…

sudo gprbuild compile_ada_hana.gpr

One the executable is done…we can run it like this…

./ada_hana

If you are wondering…why didn’t I use JSON instead of XML? Well…there’s an easy explanation for that -:) The JSON library is nice…but I had some troubles compiling it and there’s not much examples on how to retrieve the data from a complex JSON…so using XML looked like an easier and better choice  -;)

Greetings,

Blag.
Development Culture.