user> toto
{:pim 1, :pam {:poum [{:pif 1, :paf 2}]}}
user> (let [{:keys [pim]
{:keys [poum] [{:keys [pif paf]}] :poum} :pam} toto]
{:pim pim :poum poum :pif pif :paf paf})
{:pim 1, :poum [{:pif 1, :paf 2}], :pif 1, :paf 2}
A bozo's blog
Wednesday, June 26, 2019
Clojure: nested destructuring
Tuesday, May 21, 2019
macOS: access hidden user Library in Time Machine
- Enter Time Machine
- Type Cmd Shift G
- Input ~/Library
Tuesday, April 23, 2019
postgreSQL: get some table statistics
select * from pg_stat_all_tables where schemaname = 'short_message_db' and relname = 'dt_msg'; select * from pg_statio_all_tables where schemaname = 'short_message_db' and relname = 'dt_msg';
Wednesday, April 3, 2019
macOS: bash error: declare: -A: invalid option
[jerome@jeroboam] > ./avws-stores.sh
+++ dirname ./avws-stores.sh
++ cd .
++ pwd
+ SCRIPT_DIR=/Users/jerome/src/boss-sms-vas/release
+ REPO_NAME=boss-sms-vas-stores
+ declare -A AWS_S3_BUCKETS
./avws-stores.sh: line 16: declare: -A: invalid option
declare: usage: declare [-afFirtx] [-p] [name[=value] ...]
Source: Upgrading Bash on macOS
[jerome@jeroboam] > brew install bash
[jerome@jeroboam] > sudo vi /etc/shells
/bin/bash /bin/csh /bin/ksh /bin/sh /bin/tcsh /bin/zsh /usr/local/bin/bash
[jerome@jeroboam] > chsh -s /usr/local/bin/bash
AWS: list Aurora supported PostgreSQL versions
[jerome@jeroboam] > aws rds describe-db-engine-versions --engine aurora-postgresql --region eu-west-1
[
...
{
"Engine": "aurora-postgresql",
"DBParameterGroupFamily": "aurora-postgresql10",
"SupportsLogExportsToCloudwatchLogs": false,
"SupportsReadReplica": false,
"DBEngineDescription": "Aurora (PostgreSQL)",
"SupportedEngineModes": [
"provisioned"
],
"EngineVersion": "10.6",
"DBEngineVersionDescription": "Aurora PostgreSQL (compatible with PostgreSQL 10.6)",
"ValidUpgradeTarget": []
}
]
Monday, April 1, 2019
Clojure spec: key required depending on another key value
;; status > 0 => msgid required
(defmulti sendmt-rsp-mm (fn [rsp] (-> rsp :status (clojure.string/starts-with? "-")))) ; Actually means: status < 0
(defmethod sendmt-rsp-mm false [_] (s/keys :req-un [::status
::msgid]))
(defmethod sendmt-rsp-mm true [_] (s/keys :req-un [::status
::text]))
(s/def ::sendmt-rsp (s/multi-spec sendmt-rsp-mm (fn [gen-v _] gen-v)))
or
(s/def ::sendmt-rsp (s/and (s/keys :req-un [::status])
#(if (clojure.string/starts-with? (:status %) "-")
(contains? % :text)
(contains? % :msgid))))
user> (s/valid? ::sendmt-rsp {:status "2" :text "caca"})
false
user> (s/valid? ::sendmt-rsp {:status "2" :msgid "caca"})
true
user> (s/valid? ::sendmt-rsp {:status "-2" :text "caca"})
true
user> (s/valid? ::sendmt-rsp {:status "-2" :msgid "caca"})
false
Friday, March 22, 2019
postgreSQL: collapse contiguous ranges
Source: Efficiently select beginning and end of multiple contiguous ranges in Postgresql query
Or if we do not have a "last" column.
The problem is that with recursive tends to be slow when dealing with millions of rows.
How to find the boundaries of groups of contiguous sequential numbers? proposes a faster approach.
with recursive
data as (
select * from (
values ('foo', 2, 3),
('foo', 3, 4),
('foo', 4, 5),
('foo', 10, 11),
('foo', 11, 13),
('foo', 13, 15),
('bar', 1, 2),
('bar', 2, 4),
('bar', 7, 8)
) as baz (name, first, last)
),
recur (name, first, last) as (
select name, first, last, last-first as span from data
union all
select name, data.first, data.last, recur.span+data.last-data.first as span
from data join recur using (name)
where data.first = recur.last
)
select name, start, start + span as end, span from (
select name, (last-span) as start, max(span) as span from (
select name, first, last, max(span) as span
from recur
group by name, first, last
) as z
group by name, (last-span)
) as z
┌──────┬───────┬─────┬──────┐
│ name │ start │ end │ span │
├──────┼───────┼─────┼──────┤
│ bar │ 1 │ 4 │ 3 │
│ bar │ 7 │ 8 │ 1 │
│ foo │ 10 │ 15 │ 5 │
│ foo │ 2 │ 5 │ 3 │
└──────┴───────┴─────┴──────┘
(4 rows)
Or if we do not have a "last" column.
with recursive
data as (
select * from (
values ('foo', 2),
('foo', 3),
('foo', 4),
('foo', 10),
('foo', 11),
('foo', 13),
('bar', 1),
('bar', 2),
('bar', 7)
) as baz (name, first)
),
recur (name, first) as (
select name, first, 1 as span from data
union all
select name, data.first, recur.span+1 as span
from data
join recur using (name)
where data.first = recur.first + 1
)
select name, start, start + span - 1 as end, span from (
select name, (first+1-span) as start, max(span) as span from (
select name, first, max(span) as span
from recur
group by name, first
) as z
group by name, start
) as z
order by name, start
┌──────┬───────┬─────┬──────┐
│ name │ start │ end │ span │
├──────┼───────┼─────┼──────┤
│ bar │ 1 │ 2 │ 2 │
│ bar │ 7 │ 7 │ 1 │
│ foo │ 2 │ 4 │ 3 │
│ foo │ 10 │ 11 │ 2 │
│ foo │ 13 │ 13 │ 1 │
└──────┴───────┴─────┴──────┘
(5 rows)
The problem is that with recursive tends to be slow when dealing with millions of rows.
How to find the boundaries of groups of contiguous sequential numbers? proposes a faster approach.
with
data as (
select * from (
values ('foo', 2),
('foo', 3),
('foo', 4),
('foo', 10),
('foo', 11),
('foo', 13),
('bar', 1),
('bar', 2),
('bar', 7)
) as baz (name, first)
),
island as (
select first - row_number() over (order by name, first) as grp,
name, first
from data
)
select name, min(first) as start, max(first) as end
from island
group by name, grp
order by name, start
┌──────┬───────┬─────┐
│ name │ start │ end │
├──────┼───────┼─────┤
│ bar │ 1 │ 2 │
│ bar │ 7 │ 7 │
│ foo │ 2 │ 4 │
│ foo │ 10 │ 11 │
│ foo │ 13 │ 13 │
└──────┴───────┴─────┘
(5 rows)
Thursday, March 14, 2019
macOS: terminal UTF-8 issues
If you cannot display unicode characters in psql, e.g.
[jerome@jeroboam] > psql mydb
mydb=# \d public.tap_funky
View "public.tap_funky"
<E2><94><8C><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><AC><E2><94><80><E2><94><80><E2>
<94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><AC><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94>
<80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><80><E2><94><90>
<E2><94><82> Column <E2><94><82> Type <E2><94><82> Modifiers <E2><94><82>
Then
[jerome@jeroboam] > vi ~/.bash_profileexport LANG=en_US.UTF-8
[jerome@jeroboam] > source ~/.bash_profilemydb=# \d public.tap_funky
View "public.tap_funky"
┌─────────────┬──────────────┬───────────┐
│ Column │ Type │ Modifiers │
├─────────────┼──────────────┼───────────┤
│ oid │ oid │ │
│ schema │ name │ │
│ name │ name │ │
│ owner │ name │ │
│ args │ text │ │
│ returns │ text │ │
│ langoid │ oid │ │
│ is_strict │ boolean │ │
│ is_agg │ boolean │ │
│ is_definer │ boolean │ │
│ returns_set │ boolean │ │
│ volatility │ character(1) │ │
│ is_visible │ boolean │ │
└─────────────┴──────────────┴───────────┘
macOS: Library not loaded: /usr/local/opt/readline/lib/libreadline.7.dylib
If you get:
[jerome@jeroboam] > psql mydb
dyld: Library not loaded: /usr/local/opt/readline/lib/libreadline.7.dylib
Referenced from: /usr/local/bin/psql
Reason: image not found
Abort trap: 6
[jerome@jeroboam] > ln -s /usr/local/opt/readline/lib/libreadline.8.0.dylib /usr/local/opt/readline/lib/libreadline.7.dylib
Monday, March 4, 2019
AWS MFA with Yubikey and macOS
Purpose: Take advantage of the Yubikey to generate the 6 digit TOTP required by AWS MFA without using Google Authenticator.
Downside: You can't just press the Yubikey button and have the code generated as you would expect, but this can be alleviated with a keyboard shortcut.
Sources:
but macOS Mojave, Automator “Not authorized to send Apple events to System Events.” gave the solution:
I quote:
Downside: You can't just press the Yubikey button and have the code generated as you would expect, but this can be alleviated with a keyboard shortcut.
Sources:
- Use a YubiKey as a MFA device to replace Google Authenticator
- Faster AWS/PayPal/TOTP two factor auth with Yubikey
- Install the Yubikey CLI
- Insert the Yubikey
- Show a list of configured TOTP accounts
- Log in to AWS Management Console as usual, pop up the menu by clicking on your user name and select My Security Credentials.
- Push the "Manage MFA Device" button.
- Select Remove to disable MFA, and then re-start the procedure to activate MFA again.
- In the next screen, select “Virtual MFA device”.
- Show the secret key: it will be passed to ykman.
- Configure MFA for your service.
- Then, this will get you a 6 digit code.
- Start Automator, and create a new Quick Action.
- Search for applescript.
- Drag and drop "Run applescript" to the right hand side, select "Workflow receives no input", and type the following code.
- Then File | Save, and go to System Preferences | Keyboard | Shortcuts | Services to assign a shortcut to your new service.
- Now, simply log in the AWS Management Console with your password, and when the site asks for the MFA, use the programmed shortcut, which will automatically generate the 6 digit code and grant you access.
brew install ykman[jerome@jeroboam] > ykman oath list
[jerome@jeroboam] > 
[jerome@jeroboam] > ykman oath add 'Amazon Web Services:toto@org-prod' [jerome@jeroboam] > ykman oath code --single 'Amazon Web Services:toto@org-prod'
but macOS Mojave, Automator “Not authorized to send Apple events to System Events.” gave the solution:
I quote:
System Preferences > Security & Privacy > Accessibility > Click Automator and TADA it works.End quote
Wednesday, January 9, 2019
macOS: merge 2 terminals in tabs
Source: How can I merge two terminal windows in OS X lion?
This still actually works with macOS 10.14.2
This still actually works with macOS 10.14.2
Friday, December 21, 2018
Github: retrieve individual files from Github in a Dockerfile
FROM alpine:edge ARG githubtoken=1852... RUN apk add --no-cache curl wget RUN curl -o /var/mbqt/lib/MBQT/Bootstrap.pm -H "Authorization: token $githubtoken" -H 'Accept: application/vnd.github.v3.raw' -L https://api.github.com/repos// /contents/perl/lib/MBQT/Bootstrap.pm
Monday, December 17, 2018
PostgreSQL: output from multi-line pl/pgsql from psql from perl
#!/usr/bin/perl
my $cmd = "psql -Xq --set ON_ERROR_STOP=on --dbname crmmbqt <<'EOS'
";
$cmd .= <<'END';
do
$$
begin
raise notice '%', pg_is_in_recovery();
end
$$
END
$cmd .= 'EOS
';
print `$cmd`;
PostgreSQL: see the age of locks
Source: https://wiki.postgresql.org/wiki/Lock_Monitoring
select a.pid, c.relname, l.transactionid, l.mode, l.granted, a.usename, a.query, a.query_start, age(now(), a.query_start) as "age" from pg_stat_activity a join pg_locks l on l.pid = a.pid join pg_class c on c.oid = l.relation order by a.query_start
Thursday, December 13, 2018
macOS: match PC keyboard with apple keyboard
In order to match the order of the modifier keys between both types of keyboards, we need to reverse the Option key (⌥) and the Command key (⌘) on the PC keyboard. This can be done in Settings | Keyboard.
This way, we can have, Ctrl, Windows, Alt
match ^, ⌥, ⌘
Wednesday, December 12, 2018
Docker: difference between container and image
Source: In Docker, what's the difference between a container and an image?
See explanation from cbare: "Images are frozen immutable snapshots of live containers..."
See explanation from cbare: "Images are frozen immutable snapshots of live containers..."
Tuesday, December 11, 2018
Emacs: How can I tell emacs not to break long lines?
Source: How can I tell emacs not to break long lines?
M-x auto-fill-modeWednesday, November 21, 2018
GitHub: search code
In order to search code in all the repo of a user, use e.g. 
OPERATOR_CONNECTION user:AirVantage
Thursday, November 15, 2018
Perl: shortest slurp
Source: Perl Slurp-Eaze
my $str = 'my '.do { local(@ARGV, $/) = $pl_filename; <> };
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