Interesting problem requiring us to remove the where values on an ActiveRecord::Relation. The original heavy handed method seems to play havoc with chained where calls and the id of the original proxy_association.owner would get used in a later where. Here we can see that our for_me method seems to cause the else_id to be the same as our recipient_id
[5] pry(#<RSpec::Core::ExampleGroup::Nested_1::Nested_7::Nested_1>)> user.somethings.where(else_id: something.else_id).to_sql
=> "SELECT `somethings`.* FROM `somethings` WHERE `somethings`.`user_id` = 20323 AND `somethings`.`else_id` = 6465 ORDER BY id DESC"
[6] pry(#<RSpec::Core::ExampleGroup::Nested_1::Nested_7::Nested_1>)> user.somethings.for_me.where(else_id: something.else_id).to_sql
=> "SELECT `somethings`.* FROM `somethings` WHERE `somethings`.`recipient_id` = 20323 AND `somethings`.`else_id` = 20323 ORDER BY id DESC
when in doubt read the Rails source
# remove user_id = proxy_association.owner.id from scope
# so it can be reapplied by to_me or for_me
def global_scope
- s = respond_to?(:scoped) ? scoped : all
- s.where_values = []
- s
+ unscope(where: :user_id)
end
which is the way that rewhere reassigns values in where rather than chaining again
2.2.2 :006 > Something.where(user_id: 1).where(user_id: 2).to_sql
=> "SELECT `somethings`.* FROM `somethings` WHERE `somethings`.`user_id` = 1 AND `somethings`.`user_id` = 2"
2.2.2 :007 > Something.where(user_id: 1).rewhere(user_id: 2).to_sql
=> "SELECT `somethings`.* FROM `somethings` WHERE `somethings`.`user_id` = 2"
class Creature < ActiveRecord::Base
scope :is_good_pet, -> {
where(
arel_table[:is_cat].eq(true)
.or(arel_table[:is_dog].eq(true))
.or(arel_table[:eats_children].eq(false))
)
}
end
Nice…
class Person < ActiveRecord::Base
has_many :pets
end
person.pets.count # => 1
person.pets.many? # => false
person.pets << Pet.new(name: 'Snoopy')
person.pets.count # => 2
person.pets.many? # => true
Whilst trying to clean up old blog posts. I thought I’d just re-assign the whole post on the console. However, the content of the post had code examples and these examples were being interpolated. This makes sense but isn’t what I wanted. These are all (nearly) equivalent other than the new lines.
s =<<-STR
#{Time.now}
STR
# => "2017-01-17 06:43:48 -0500"
s = %(
#{Time.now}
)
# => "\n2017-01-17 06:43:48 -0500\n"
s = %Q(
#{Time.now}
)
# => "\n2017-01-17 06:43:48 -0500\n"
But what I really want it multi-line string assignment without interpolation.
s = %q(
#{Time.now}
)
# => "\n\#{Time.now}\n"
And without the new lines.
s = %q(
#{Time.now}
).lstrip.chop
# => "\#{Time.now}"
Instagram Subscriptions
Loading development environment (Rails 5.0.1)
2.3.0 :001 > puts JSON.parse(Infectious::Instagram.subscribe('http://robl.me/instagram/subscriptions/callback','dave').body).to_yaml
ETHON: Libcurl initialized
ETHON: performed EASY effective_url=https://api.instagram.com/v1/subscriptions response_code=200 return_code=ok total_time=1.394347
---
meta:
code: 200
data:
object: user
object_id:
aspect: media
subscription_id: 0
callback_url: http://robl.me/instagram/subscriptions/callback
type: subscription
id: 0
Not sure what to make of this at all.
class Cat
def call(*args)
(args).join(' ^O^ ')
end
end
Cat.new.(:samson, :smeagol, :gimmick)
Interesting, ActiveRecord joins issues today. Recently upgraded to Rails 4.0 and working on clearing odd occasional bugs.
Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DISTINCT grapes.id, grapes.* FROM `grapes` INNER JOIN `tickets` ON `z' at line 1: SELECT `pledges`.`id` AS t0_r0, ...., DISTINCT grapes.id, grapes.* FROM `grapes` INNER JOIN `tickets` ....
We specifically need a DISTINCT in here so that we don’t end up with duplicate rows. However, overwriting the select for *eager_load*ed statements isn’t going to work, in fact it appears to just append our select causing the above error. So…
- scope = scope.joins(:tickets).select('DISTINCT grapes.id, grapes.*')
+ scope = scope.joins(:tickets).distinct('grapes.id')
Don’t use .select(‘DISTINCT … when eager_loading is likely to kick in. You’ll end up with something like.
SELECT `grapes`.`id` AS t0_r0, ..... DISTINCT(grapes.id), grapes.* FROM grapes;
Which will break, since you can’t have two DISTINCT in a SELECT.
Want to work out if any of your columns contain Unicode Characters?
Something.where('LENGTH(data) != CHAR_LENGTH(data)').first
But it is empty???
rails@snarf:~$ ls -la /var/www/robl.me/releases/20160323235726/tmp/cache/assets/sprockets/v3.0
total 40
drwxrwxr-x 2 rails rails 36864 Dec 16 15:11 .
drwxrwxr-x 3 rails rails 4096 Mar 23 2016 ..
rails@snarf:~$ rmdir /var/www/robl.me/releases/20160323235726/tmp/cache/assets/sprockets/v3.0
rmdir: failed to remove ‘/var/www/robl.me/releases/20160323235726/tmp/cache/assets/sprockets/v3.0’: Directory not empty
Just went hunting for Date and Time formats, found this.
activesupport-5.0.0.beta3/lib/active_support/locale/en.yml
en:
date:
formats:
# Use the strftime parameters for formats.
# When no format has been given, it uses default.
# You can provide other formats here if you like!
default: "%Y-%m-%d"
short: "%b %d"
long: "%B %d, %Y"
day_names: [Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday]
abbr_day_names: [Sun, Mon, Tue, Wed, Thu, Fri, Sat]
# Don't forget the nil at the beginning; there's no such thing as a 0th month
month_names: [~, January, February, March, April, May, June, July, August, September, October, November, December]
abbr_month_names: [~, Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec]
# Used in date_select and datetime_select.
order:
- year
- month
- day
time:
formats:
default: "%a, %d %b %Y %H:%M:%S %z"
short: "%d %b %H:%M"
long: "%B %d, %Y %H:%M"
am: "am"
pm: "pm"
# Used in array.to_sentence.
support:
array:
words_connector: ", "
two_words_connector: " and "
last_word_connector: ", and "
number:
# Used in NumberHelper.number_to_delimited()
# These are also the defaults for 'currency', 'percentage', 'precision', and 'human'
format:
# Sets the separator between the units, for more precision (e.g. 1.0 / 2.0 == 0.5)
separator: "."
# Delimits thousands (e.g. 1,000,000 is a million) (always in groups of three)
delimiter: ","
# Number of decimals, behind the separator (the number 1 with a precision of 2 gives: 1.00)
precision: 3
# If set to true, precision will mean the number of significant digits instead
# of the number of decimal digits (1234 with precision 2 becomes 1200, 1.23543 becomes 1.2)
significant: false
# If set, the zeros after the decimal separator will always be stripped (eg.: 1.200 will be 1.2)
strip_insignificant_zeros: false
# Used in NumberHelper.number_to_currency()
currency:
format:
# Where is the currency sign? %u is the currency unit, %n the number (default: $5.00)
format: "%u%n"
unit: "$"
# These five are to override number.format and are optional
separator: "."
delimiter: ","
precision: 2
significant: false
strip_insignificant_zeros: false
# Used in NumberHelper.number_to_percentage()
percentage:
format:
# These five are to override number.format and are optional
# separator:
delimiter: ""
# precision:
# significant: false
# strip_insignificant_zeros: false
format: "%n%"
# Used in NumberHelper.number_to_rounded()
precision:
format:
# These five are to override number.format and are optional
# separator:
delimiter: ""
# precision:
# significant: false
# strip_insignificant_zeros: false
# Used in NumberHelper.number_to_human_size() and NumberHelper.number_to_human()
human:
format:
# These five are to override number.format and are optional
# separator:
delimiter: ""
precision: 3
significant: true
strip_insignificant_zeros: true
# Used in number_to_human_size()
storage_units:
# Storage units output formatting.
# %u is the storage unit, %n is the number (default: 2 MB)
format: "%n %u"
units:
byte:
one: "Byte"
other: "Bytes"
kb: "KB"
mb: "MB"
gb: "GB"
tb: "TB"
pb: "PB"
eb: "EB"
# Used in NumberHelper.number_to_human()
decimal_units:
format: "%n %u"
# Decimal units output formatting
# By default we will only quantify some of the exponents
# but the commented ones might be defined or overridden
# by the user.
units:
# femto: Quadrillionth
# pico: Trillionth
# nano: Billionth
# micro: Millionth
# mili: Thousandth
# centi: Hundredth
# deci: Tenth
unit: ""
# ten:
# one: Ten
# other: Tens
# hundred: Hundred
thousand: Thousand
million: Million
billion: Billion
trillion: Trillion
quadrillion: Quadrillion