Python locale settings on Heroku

Question

I'm developing a python web application on Heroku and I'm facing a problem with the locale settings.

My aim ist to format a python datetime object as a string like this

import datetime
now = datetime.datetime.now()
print now.strftime('%a %d %B %Y')  # output: Sat 14 July 2012

but in different languages.

On my local machine I use therefore:

import locale
locale.setlocale(locale.LC_ALL, '')

or locale.setlocale(locale.LC_ALL, 'de_DE.UTF-8') for specific languages.

On my local machine this works and I get the date in the right language but on Heroku it fails and all I get is a locale.Error: unsupported locale settings.

Am I doing something wrong or is it permitted to change locale setting in a python app on Heroku?

Thanks.

Answer 1

You can see available locales by running:

$ heroku run "locale -a"
Running `locale -a` attached to terminal... up, run.5061
aa_DJ.utf8
aa_ER
aa_ER@saaho
aa_ET
af_ZA.utf8
am_ET
an_ES.utf8
ar_AE.utf8
ar_BH.utf8
ar_DZ.utf8
ar_EG.utf8
ar_IN
ar_IQ.utf8
ar_JO.utf8
ar_KW.utf8
ar_LB.utf8
ar_LY.utf8
ar_MA.utf8
ar_OM.utf8
ar_QA.utf8
ar_SA.utf8
ar_SD.utf8
ar_SY.utf8
ar_TN.utf8
ar_YE.utf8
as_IN
ast_ES.utf8
az_AZ
be_BY@latin
be_BY.utf8
ber_DZ
ber_MA
bg_BG.utf8
bn_BD
bn_IN
bo_CN
bo_IN
br_FR.utf8
bs_BA.utf8
C
ca_AD.utf8
ca_ES.utf8
ca_ES.utf8@valencia
ca_FR.utf8
ca_IT.utf8
crh_UA
csb_PL
cs_CZ.utf8
cy_GB.utf8
da_DK.utf8
de_AT.utf8
de_BE.utf8
de_CH.utf8
de_DE.utf8
de_LI.utf8
de_LU.utf8
dv_MV
dz_BT
el_CY.utf8
el_GR.utf8
en_AG
en_AU.utf8
en_BW.utf8
en_CA.utf8
en_DK.utf8
en_GB.utf8
en_HK.utf8
en_IE.utf8
en_IN
en_NG
en_NZ.utf8
en_PH.utf8
en_SG.utf8
en_US.utf8
en_ZA.utf8
en_ZW.utf8
eo_US.utf8
eo.utf8
es_AR.utf8
es_BO.utf8
es_CL.utf8
es_CO.utf8
es_CR.utf8
es_DO.utf8
es_EC.utf8
es_ES.utf8
es_GT.utf8
es_HN.utf8
es_MX.utf8
es_NI.utf8
es_PA.utf8
es_PE.utf8
es_PR.utf8
es_PY.utf8
es_SV.utf8
es_US.utf8
es_UY.utf8
es_VE.utf8
et_EE.utf8
eu_ES.utf8
eu_FR.utf8
fa_IR
fi_FI.utf8
fil_PH
fo_FO.utf8
fr_BE.utf8
fr_CA.utf8
fr_CH.utf8
fr_FR.utf8
fr_LU.utf8
fur_IT
fy_DE
fy_NL
ga_IE.utf8
gd_GB.utf8
gl_ES.utf8
gu_IN
ha_NG
he_IL.utf8
hi_IN
hne_IN
hr_HR.utf8
hsb_DE.utf8
ht_HT
hu_HU.utf8
hy_AM
ia
id_ID.utf8
ig_NG
is_IS.utf8
it_CH.utf8
it_IT.utf8
iu_CA
ja_JP.utf8
ka_GE.utf8
kk_KZ.utf8
km_KH
kn_IN
ko_KR.utf8
ks_IN
ks_IN@devanagari
ku_TR.utf8
kw_GB.utf8
ky_KG
la_AU.utf8
lg_UG.utf8
li_BE
li_NL
lo_LA
lt_LT.utf8
lv_LV.utf8
mai_IN
mg_MG.utf8
mi_NZ.utf8
mk_MK.utf8
ml_IN
mn_MN
mr_IN
ms_MY.utf8
mt_MT.utf8
nan_TW@latin
nb_NO.utf8
nds_DE
nds_NL
ne_NP
nl_AW
nl_BE.utf8
nl_NL.utf8
nn_NO.utf8
nr_ZA
nso_ZA
oc_FR.utf8
om_ET
om_KE.utf8
or_IN
pa_IN
pap_AN
pa_PK
pl_PL.utf8
POSIX
pt_BR.utf8
pt_PT.utf8
ro_RO.utf8
ru_RU.utf8
ru_UA.utf8
rw_RW
sa_IN
sc_IT
sd_IN
sd_IN@devanagari
se_NO
shs_CA
si_LK
sk_SK.utf8
sl_SI.utf8
so_DJ.utf8
so_ET
so_KE.utf8
so_SO.utf8
sq_AL.utf8
sr_ME
sr_RS
sr_RS@latin
ss_ZA
st_ZA.utf8
sv_FI.utf8
sv_SE.utf8
ta_IN
te_IN
tg_TJ.utf8
th_TH.utf8
ti_ER
ti_ET
tk_TM
tlh_GB.utf8
tl_PH.utf8
tn_ZA
tr_CY.utf8
tr_TR.utf8
ts_ZA
tt_RU
tt_RU@iqtelif
ug_CN
uk_UA.utf8
ur_PK
uz_UZ@cyrillic
uz_UZ.utf8
ve_ZA
vi_VN
wa_BE.utf8
wo_SN
xh_ZA.utf8
yi_US.utf8
yo_NG
zh_CN.utf8
zh_HK.utf8
zh_SG.utf8
zh_TW.utf8
zu_ZA.utf8

To fix your issue try

locale.setlocale(locale.LC_ALL, 'de_DE.utf8')

or

heroku config:add LANG=de_DE.utf8