Gross Domestic Product and Software Developers

This project provides and endpoint that receives a country's ISO code and returns its gross domestic product as well as the youngest age that developers started coding for that country. Source:

• European Gross Domestic Product for 2021*
• Stackoverflow 2021 survey's responses*

*Since 2022's GDP was incomplete, 2021 information was used

Installation

pip install -r requirements.txt

Load db

./manage.py load_db

Run tests

./manage.py test

Run server

./manage.py runserver

Endpoint example

GET http://localhost:8000/processors/gdp_youngest_age/BE/

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Project

This project was developed using Django and Django Rest Framework for convenience when building the API and the DB tables.

It uses a sqlite database for its simplicity.

The command load_db is provided to import all the information to the database.

When importing all the data, the library pycountry is used to get the countries' ISO code.

For convenience when querying the age when developers started to code, I parsed the string coming from the survey to min-max ranges in the database.

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Part 1

In order to get the most frequent first coding age of each european country and their corresponding amount of developers I used the following query:

SELECT "country_name", "min_age_first_code", "max_age_first_code", max("dcount") FROM (SELECT rs.country_name, rs.min_age_first_code, rs.max_age_first_code, count("min_age_first_code") AS "dcount" FROM readers_stackoverflowresponse rs JOIN readers_grossdomesticproduct rg ON rs.country_name = rg.country_name GROUP BY rs.country_name, rs.min_age_first_code) GROUP BY "country_name";

This returns:

country_name	min_age_first_code	max_age_first_code	max("dcount")
albania	11	17	28
austria	11	17	545
belgium	11	17	446
bulgaria	11	17	239
croatia	11	17	156
cyprus	11	17	39
denmark	11	17	374
estonia	11	17	81
finland	11	17	288
france	11	17	1597
greece	11	17	309
hungary	11	17	273
iceland	11	17	25
ireland	11	17	187
italy	11	17	1003
latvia	11	17	72
lithuania	11	17	148
luxembourg	11	17	29
malta	11	17	24
montenegro	11	17	11
netherlands	11	17	1043
norway	11	17	338
poland	11	17	1136
portugal	11	17	298
romania	11	17	461
serbia	11	17	182
slovakia	11	17	163
slovenia	11	17	151
spain	11	17	773
sweden	11	17	711
switzerland	11	17	618

We can see that for all european countries, the most frequent starting age for developers is between 11 and 17 years old. Since the age is not variable, we cannot define a determined relationship between this age and the GDP of the country.

Part 2

In order to increase the scalability of this endpoint, we could:

• Use a cache to access the data quicker and don't affect the performance, since this information is loaded once a year, and it won't change with the passage of time.
• If the amount of survey responses increased, an index could be used to enhance the speed of the query.

Part 3

Since sqlite has no pivot query, I used two queries to show the data.

In order to show the three most popular programming languages, I used this subquery:

SELECT "name" FROM readers_programminglanguageresponse GROUP BY "name" ORDER BY count("name") DESC LIMIT 3;

This returns Javascript, HTML/CSS, Python.

To build the query that gives us information about how many developers use these programming languages in each country, I used the following query:

SELECT rs.country_name, SUM(CASE WHEN rp.name like "%Javascript%" THEN 1 ELSE 0 END) AS "Javascript", SUM(CASE WHEN rp.name like "%HTML/CSS%" THEN 1 ELSE 0 END) AS "HTML/CSS", SUM(CASE WHEN rp.name like "%Python%" THEN 1 ELSE 0 END) AS "Python" FROM readers_stackoverflowresponse rs JOIN readers_programminglanguageresponse rp on rs.id = rp.survey_response_id GROUP BY country_name;

This returns:

country_name	Javascript	HTML/CSS	Python
afghanistan	31	27	19
albania	50	43	30
algeria	29	26	19
andorra	7	5	3
angola	14	14	5
argentina	415	339	246
armenia	57	33	33
australia	1107	925	830
austria	498	438	377
azerbaijan	38	33	33
bahamas	3	1	5
bahrain	22	19	14
bangladesh	503	439	322
barbados	8	7	4
belarus	95	66	46
belgium	467	400	333
belize	2	3	3
benin	10	9	4
bhutan	4	3	3
bosnia and herzegovina	106	94	47
botswana	4	3	2
brazil	1531	1218	950
brunei darussalam	1	1	1
bulgaria	260	210	117
burkina faso	3	3	3
burundi	5	5	4
cambodia	17	16	10
cameroon	27	30	16
canada	1978	1686	1590
central african republic	2	2	1
chad	2	2	1
chile	151	119	123
china	424	327	490
colombia	278	242	176
costa rica	59	47	30
croatia	156	141	109
cuba	26	26	22
cyprus	36	27	26
côte d'ivoire	15	13	6
denmark	366	317	273
djibouti	2	2	1
dominica	1	1	1
dominican republic	84	71	29
ecuador	81	60	49
egypt	322	306	218
el salvador	26	20	10
estonia	76	71	61
ethiopia	46	43	30
fiji	1	2	1
finland	351	273	247
france	1802	1592	1422
gambia	1	1	0
georgia	100	82	59
germany	3387	3027	2711
ghana	62	59	38
greece	360	330	295
guatemala	52	42	26
guinea	2	2	1
guyana	5	4	4
haiti	4	3	3
honduras	19	18	10
hungary	298	270	209
iceland	27	17	27
india	6448	5833	5223
indonesia	452	385	256
iraq	47	49	27
ireland	234	203	193
isle of man	5	5	3
israel	521	390	514
italy	1095	959	734
jamaica	16	17	10
japan	267	210	209
jordan	43	34	22
kazakhstan	39	41	30
kenya	181	171	132
kuwait	18	18	12
kyrgyzstan	12	8	4
lao people's democratic republic	4	3	1
latvia	71	58	38
lebanon	79	78	48
lesotho	2	3	0
liberia	2	2	2
liechtenstein	0	0	1
lithuania	140	120	59
luxembourg	38	30	26
madagascar	14	13	7
malawi	9	8	4
malaysia	220	202	148
maldives	12	10	9
mali	1	1	0
malta	29	22	17
mauritania	4	4	2
mauritius	24	21	17
mexico	531	456	285
monaco	1	1	0
mongolia	17	11	10
montenegro	13	13	4
morocco	153	160	95
mozambique	9	8	3
myanmar	35	29	15
namibia	10	9	9
nepal	245	208	178
netherlands	1182	1020	831
new zealand	361	299	230
nicaragua	12	10	4
niger	2	2	1
nigeria	316	292	172
norway	367	313	257
oman	14	11	11
pakistan	572	543	323
panama	25	21	11
papua new guinea	0	0	0
paraguay	34	24	17
peru	105	92	72
philippines	280	247	155
poland	1078	901	812
portugal	363	301	219
qatar	18	24	20
romania	426	351	263
russian federation	787	623	664
rwanda	25	23	14
saint kitts and nevis	1	0	0
saint lucia	1	1	2
saint vincent and the grenadines	0	0	0
san marino	2	1	0
saudi arabia	95	87	63
senegal	26	24	16
serbia	208	184	109
sierra leone	1	1	2
singapore	226	177	203
slovakia	160	145	119
slovenia	165	135	122
somalia	4	4	3
south africa	387	353	247
spain	958	809	675
sri lanka	301	269	189
sudan	16	19	12
suriname	3	3	2
sweden	729	597	523
switzerland	580	530	469
syrian arab republic	37	36	15
tajikistan	5	7	2
thailand	116	106	86
togo	7	7	3
trinidad and tobago	13	14	8
tunisia	120	113	79
turkey	681	570	462
turkmenistan	8	9	4
tuvalu	1	1	1
uganda	49	41	33
ukraine	450	337	271
united arab emirates	124	120	80
uruguay	109	88	56
uzbekistan	33	29	31
viet nam	244	198	172
yemen	8	11	6
zambia	16	17	12
zimbabwe	22	20	17