Multi-tenancy with Rails

Multi-tenancy with Rails
Dimiter Petrov

View Slide

What is multi-tenancy?
A software architecture where a single instance of a software application
serves multiple customers.
A customer is called a tenant in this architecture.

View Slide

Advantages/problems/compromises

View Slide

Deploy once to update everyone's software,

View Slide

Deploy once to update everyone's software, but
there is single point of failure for all tenants.

View Slide

Shared development and maintenance costs,

View Slide

Shared development and maintenance costs, but
customer-specific features are burdensome.

View Slide

Single codebase,

View Slide

Single codebase, but
with configuration overhead.

View Slide

Single codebase, but
with configuration overhead.
However, after configuration, development is the same as for a classic, single-
tenant application.

View Slide

Requirements
Data access control
Custom features
Custom branding

View Slide

Data separation

View Slide

Data separation strategies
Application-level: in the controller and sometimes the model
Database-level: different databases or different PostgreSQL schemas

View Slide

PostgreSQL schemas
From the docs:
A database contains one or more named schemas, which in turn
contain tables. Schemas also contain other kinds of named objects,
including data types, functions, and operators. The same object name
can be used in different schemas without conflict
http://www.postgresql.org/docs/9.5/static/ddl-schemas.html
There is a default p
u
b
l
i
c schema, but you can create your own.

View Slide

Schema example
# c
r
e
a
t
e s
c
h
e
m
a m
y
s
c
h
e
m
a
;
# c
r
e
a
t
e t
a
b
l
e m
y
s
c
h
e
m
a
.
t
h
i
n
g
s
(
i
d s
e
r
i
a
l
)
;

View Slide

Schema search path
Used to automatically infer which table is meant without specifying it
explicitly.
# s
h
o
w s
e
a
r
c
h
_
p
a
t
h
;
s
e
a
r
c
h
_
p
a
t
h
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
"
$
u
s
e
r
"
, p
u
b
l
i
c
# s
e
t s
e
a
r
c
h
_
p
a
t
h t
o m
y
s
c
h
e
m
a
,
p
u
b
l
i
c
;
# s
h
o
w s
e
a
r
c
h
_
p
a
t
h
;
s
e
a
r
c
h
_
p
a
t
h
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
m
y
s
c
h
e
m
a
, p
u
b
l
i
c

View Slide

Schemas for data separation
1. Create one schema per tenant
2. Create all tables in all schemas
3. Detect tenant on every request and change the schema search path

View Slide

Gems
a
p
a
r
t
m
e
n
t
Multitenancy for Rails and ActiveRecord
a
p
a
r
t
m
e
n
t
-
s
i
d
e
k
i
q
Support for Sidekiq with the a
p
a
r
t
m
e
n
t gem

View Slide

Migrations
Handled by a
p
a
r
t
m
e
n
t which runs the migration for each tenant.

View Slide

Seeds
# s
e
e
d
s
.
r
b
r
e
q
u
i
r
e '
a
c
t
i
v
e
_
r
e
c
o
r
d
/
f
i
x
t
u
r
e
s
'
r
e
q
u
i
r
e R
a
i
l
s
.
r
o
o
t
.
j
o
i
n
(
'
l
i
b
/
f
i
x
t
u
r
e
_
l
o
a
d
e
r
'
)
f
i
x
t
u
r
e
s
_
d
i
r
e
c
t
o
r
y =
R
a
i
l
s
.
r
o
o
t
.
j
o
i
n
(
"
d
b
/
s
e
e
d
s
/
#
{
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
}
"
)
F
i
x
t
u
r
e
L
o
a
d
e
r
:
:
l
o
a
d
_
d
i
r
e
c
t
o
r
y
(
f
i
x
t
u
r
e
s
_
d
i
r
e
c
t
o
r
y
)
# l
i
b
/
f
i
x
t
u
r
e
_
l
o
a
d
e
r
.
r
b
c
l
a
s
s F
i
x
t
u
r
e
L
o
a
d
e
r
d
e
f s
e
l
f
.
l
o
a
d
_
d
i
r
e
c
t
o
r
y
(
d
i
r
e
c
t
o
r
y
)
u
n
l
e
s
s D
i
r
.
e
x
i
s
t
?
(
d
i
r
e
c
t
o
r
y
)
r
a
i
s
e A
r
g
u
m
e
n
t
E
r
r
o
r
.
n
e
w
(
"
#
{
d
i
r
e
c
t
o
r
y
} d
o
e
s n
o
t e
x
i
s
t
!
"
)
e
n
d
A
c
t
i
v
e
R
e
c
o
r
d
:
:
F
i
x
t
u
r
e
S
e
t
.
r
e
s
e
t
_
c
a
c
h
e
D
i
r
.
g
l
o
b
(
d
i
r
e
c
t
o
r
y
.
j
o
i
n
(
"
*
*
/
*
"
)
)
.
e
a
c
h d
o |
f
i
l
e
n
a
m
e
|
f
i
x
t
u
r
e = P
a
t
h
n
a
m
e
.
n
e
w
(
f
i
l
e
n
a
m
e
.
c
h
o
m
p
(
'
.
y
m
l
'
)
)
.
b
a
s
e
n
a
m
e
A
c
t
i
v
e
R
e
c
o
r
d
:
:
F
i
x
t
u
r
e
S
e
t
.
c
r
e
a
t
e
_
f
i
x
t
u
r
e
s
(
d
i
r
e
c
t
o
r
y
, f
i
x
t
u
r
e
)
e
n
d
e
n
d
e
n
d

View Slide

PostgreSQL shared extensions
From the a
p
a
r
t
m
e
n
t gem documentation:
When using extensions, keep in mind:
Extensions can only be installed into one schema per database, so
we will want to install it into a schema that is always available in
the schema_search_path
The schema and extension need to be created in the database
before they are referenced in migrations, database.yml or
apartment.
There does not seem to be a way to create the schema and
extension using standard rails migrations.
Rails db:test:prepare deletes and recreates the database, so it
needs to be easy for the extension schema to be recreated here.

View Slide

PostgreSQL shared extensions
p
s
q
l -
U p
o
s
t
g
r
e
s -
c "
C
R
E
A
T
E D
A
T
A
B
A
S
E t
e
m
p
l
a
t
e
_
a
p
p
;
p
s
q
l -
U p
o
s
t
g
r
e
s -
d t
e
m
p
l
a
t
e
_
a
p
p -
c \
"
C
R
E
A
T
E S
C
H
E
M
A I
F N
O
T E
X
I
S
T
S s
h
a
r
e
d
_
e
x
t
e
n
s
i
o
n
s
; \
C
R
E
A
T
E E
X
T
E
N
S
I
O
N I
F N
O
T E
X
I
S
T
S h
s
t
o
r
e S
C
H
E
M
A s
h
a
r
e
d
_
e
x
t
e
n
s
i
o
n
s
;
"
# d
a
t
a
b
a
s
e
.
y
m
l
d
e
f
a
u
l
t
: &
d
e
f
a
u
l
t
a
d
a
p
t
e
r
: p
o
s
t
g
r
e
s
q
l
e
n
c
o
d
i
n
g
: u
n
i
c
o
d
e
t
e
m
p
l
a
t
e
: t
e
m
p
l
a
t
e
_
a
p
p
Also had to use s
t
r
u
c
t
u
r
e
.
s
q
l instead of s
c
h
e
m
a
.
r
b
.

View Slide

Uploaded assets
P
a
p
e
r
c
l
i
p
:
:
A
t
t
a
c
h
m
e
n
t
.
d
e
f
a
u
l
t
_
o
p
t
i
o
n
s
[
:
u
r
l
] =
"
/
:
c
l
a
s
s
/
:
t
e
n
a
n
t
/
:
a
t
t
a
c
h
m
e
n
t
/
:
i
d
/
:
s
t
y
l
e
/
:
u
p
d
a
t
e
d
_
a
t
"
P
a
p
e
r
c
l
i
p
:
:
A
t
t
a
c
h
m
e
n
t
.
d
e
f
a
u
l
t
_
o
p
t
i
o
n
s
[
:
p
a
t
h
] =
R
a
i
l
s
.
r
o
o
t
.
j
o
i
n
(
'
f
i
l
e
s
'
)
.
j
o
i
n
(
"
:
c
l
a
s
s
/
:
t
e
n
a
n
t
/
:
a
t
t
a
c
h
m
e
n
t
/
:
i
d
/
:
s
t
y
l
e
/
:
u
p
d
a
t
e
d
_
a
t
"
)
.
t
o
_
s
P
a
p
e
r
c
l
i
p
.
i
n
t
e
r
p
o
l
a
t
e
s :
t
e
n
a
n
t d
o |
a
t
t
a
c
h
m
e
n
t
, s
t
y
l
e
|
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
e
n
d
# o
t
h
e
r i
n
t
e
r
p
o
l
a
t
i
o
n
s
.
.
.

View Slide

Business logic separation

View Slide

Feature gates
A simple table with three columns: ID, feature name and a creation
timestamp.
c
l
a
s
s F
e
a
t
u
r
e < A
c
t
i
v
e
R
e
c
o
r
d
:
:
B
a
s
e
d
e
f s
e
l
f
.
e
n
a
b
l
e
d
?
(
n
a
m
e
)
w
h
e
r
e
(
n
a
m
e
: n
a
m
e
)
.
e
x
i
s
t
s
?
e
n
d
e
n
d
Remember: the contents of this table can be different for every tenant thanks
to PosgreSQL schemas.

View Slide

Scheduled jobs
d
e
f
a
u
l
t
: &
d
e
f
a
u
l
t
c
l
a
s
s
: '
T
a
s
k
W
o
r
k
e
r
'
q
u
e
u
e
: '
c
r
o
n
'
r
e
t
r
i
e
s
: 0
s
e
n
d
_
r
e
c
a
p
_
e
m
a
i
l
s
:
<
<
: *
d
e
f
a
u
l
t
c
r
o
n
: "
0 2 * * *
" # 2
:
0
0 e
v
e
r
y d
a
y
a
r
g
s
: [
'
s
e
n
d
_
r
e
c
a
p
_
e
m
a
i
l
s
'
]
Results in something like
w
o
r
k
e
r = T
a
s
k
W
o
r
k
e
r
.
n
e
w
(
o
p
t
i
o
n
s
)
w
o
r
k
e
r
.
p
e
r
f
o
r
m
(
'
s
e
n
d
_
r
e
c
a
p
_
e
m
a
i
l
s
'
)

View Slide

Scheduled jobs
c
l
a
s
s T
a
s
k
W
o
r
k
e
r
i
n
c
l
u
d
e S
i
d
e
k
i
q
:
:
W
o
r
k
e
r
s
i
d
e
k
i
q
_
o
p
t
i
o
n
s r
e
t
r
y
: f
a
l
s
e
d
e
f p
e
r
f
o
r
m
(
t
a
s
k
_
n
a
m
e
)
u
n
l
e
s
s r
e
s
p
o
n
d
_
t
o
?
(
t
a
s
k
_
n
a
m
e
)
r
a
i
s
e
(
A
r
g
u
m
e
n
t
E
r
r
o
r
, "
m
i
s
s
i
n
g t
a
s
k #
{
t
a
s
k
_
n
a
m
e
}
"
)
e
n
d
A
p
a
r
t
m
e
n
t
.
t
e
n
a
n
t
_
n
a
m
e
s
.
e
a
c
h d
o |
t
e
n
a
n
t
|
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
s
w
i
t
c
h
(
t
e
n
a
n
t
) d
o
i
f F
e
a
t
u
r
e
.
e
n
a
b
l
e
d
?
(
"
t
a
s
k
:
#
{
t
a
s
k
_
n
a
m
e
}
"
)
s
e
n
d
(
t
a
s
k
_
n
a
m
e
)
e
n
d
e
n
d
e
n
d
e
n
d
d
e
f s
e
n
d
_
r
e
c
a
p
_
e
m
a
i
l
s
; e
n
d
# .
.
.
e
n
d

View Slide

Tenant con guration le
A YAML file with configuration for all tenants (and optionally different
environments for each tenant)
t
e
n
a
n
t
1
:
<
<
: *
d
e
f
a
u
l
t
d
o
m
a
i
n
: e
x
a
m
p
l
e
.
c
o
m
s
m
t
p
:
d
o
m
a
i
n
: e
x
a
m
p
l
e
.
c
o
m
Loaded in an initializer:
r
e
q
u
i
r
e R
a
i
l
s
.
r
o
o
t
.
j
o
i
n
(
'
l
i
b
/
c
o
n
f
i
g
'
)
R
a
i
l
s
.
a
p
p
l
i
c
a
t
i
o
n
.
c
o
n
f
i
g
.
x
.
a
p
p = A
p
p
:
:
C
o
n
f
i
g
.
n
e
w

View Slide

Mailer con guration
c
l
a
s
s A
p
p
l
i
c
a
t
i
o
n
M
a
i
l
e
r < A
c
t
i
o
n
M
a
i
l
e
r
:
:
B
a
s
e
d
e
f
a
u
l
t f
r
o
m
: -
>
(
m
a
i
l
e
r
) d
o
R
a
i
l
s
.
c
o
n
f
i
g
u
r
a
t
i
o
n
.
x
.
a
p
p
.
s
e
n
d
e
r
_
e
m
a
i
l
e
n
d
l
a
y
o
u
t '
m
a
i
l
e
r
'
d
e
f s
e
l
f
.
s
m
t
p
_
s
e
t
t
i
n
g
s
s
u
p
e
r
.
m
e
r
g
e
(
R
a
i
l
s
.
c
o
n
f
i
g
u
r
a
t
i
o
n
.
x
.
a
p
p
.
s
m
t
p
.
s
y
m
b
o
l
i
z
e
_
k
e
y
s
)
e
n
d
d
e
f u
r
l
_
o
p
t
i
o
n
s
s
u
p
e
r
.
m
e
r
g
e
(
h
o
s
t
: R
a
i
l
s
.
c
o
n
f
i
g
u
r
a
t
i
o
n
.
x
.
a
p
p
.
d
o
m
a
i
n
)
e
n
d
e
n
d

View Slide

c
l
a
s
s C
o
n
f
i
g
d
e
f m
e
t
h
o
d
_
m
i
s
s
i
n
g
(
m
e
t
h
o
d
_
n
a
m
e
, *
a
r
g
s
, &
b
l
o
c
k
)
g
e
t
(
m
e
t
h
o
d
_
n
a
m
e
)
e
n
d
p
r
i
v
a
t
e
d
e
f g
e
t
(
k
e
y
, t
e
n
a
n
t = n
i
l
)
c
o
n
f
i
g =
t
e
n
a
n
t
s
_
c
o
n
f
i
g
[
t
e
n
a
n
t |
| A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
] |
| {
}
c
o
n
f
i
g = c
o
n
f
i
g
.
m
e
r
g
e
(
c
o
n
f
i
g
.
f
e
t
c
h
(
R
a
i
l
s
.
e
n
v
, {
}
)
)
c
o
n
f
i
g
.
f
e
t
c
h
(
k
e
y
.
t
o
_
s
)
r
e
s
c
u
e K
e
y
E
r
r
o
r
r
a
i
s
e K
e
y
E
r
r
o
r
, e
x
c
e
p
t
i
o
n
_
m
e
s
s
a
g
e
(
k
e
y
)
e
n
d
d
e
f t
e
n
a
n
t
s
_
c
o
n
f
i
g
@
t
e
n
a
n
t
s
_
c
o
n
f
i
g |
|
=
Y
A
M
L
:
:
l
o
a
d
(
E
R
B
.
n
e
w
(
R
a
i
l
s
.
r
o
o
t
.
j
o
i
n
(
"
f
o
o
.
y
m
l
"
)
.
r
e
a
d
)
.
r
e
s
u
l
t
)
e
n
d
d
e
f e
x
c
e
p
t
i
o
n
_
m
e
s
s
a
g
e
(
k
e
y
)
# .
.
.
e
n
d
e
n
d

View Slide

Absolute URL helpers
For use in the API
m
o
d
u
l
e U
r
l
m
o
d
u
l
e U
s
e
r
P
i
c
t
u
r
e
d
e
f s
e
l
f
.
p
a
t
h
(
u
s
e
r
, s
t
y
l
e
)
# .
.
.
e
n
d
d
e
f s
e
l
f
.
u
r
l
(
u
s
e
r
, s
t
y
l
e
)
h
o
s
t = R
a
i
l
s
.
c
o
n
f
i
g
u
r
a
t
i
o
n
.
x
.
a
p
p
.
h
o
s
t
U
R
I
.
j
o
i
n
(
h
o
s
t
, p
a
t
h
(
u
s
e
r
, s
t
y
l
e
)
)
.
t
o
_
s
e
n
d
e
n
d
e
n
d

View Slide

Error reporting
m
o
d
u
l
e E
x
c
e
p
t
i
o
n
N
o
t
i
f
i
e
r
c
l
a
s
s M
u
l
t
i
t
e
n
a
n
t
E
m
a
i
l
N
o
t
i
f
i
e
r < E
m
a
i
l
N
o
t
i
f
i
e
r
d
e
f o
p
t
i
o
n
s
s
u
p
e
r
.
t
a
p d
o |
o
p
t
s
|
e
n
v = R
a
i
l
s
.
e
n
v
.
s
t
a
g
i
n
g
? ? '
S
T
A
G
I
N
G
' : n
i
l
t
e
n
a
n
t
_
w
i
t
h
_
e
n
v
i
r
o
n
m
e
n
t =
[
c
u
r
r
e
n
t
_
t
e
n
a
n
t
, e
n
v
]
.
c
o
m
p
a
c
t
.
j
o
i
n
(
' '
)
o
p
t
s
[
:
e
m
a
i
l
_
p
r
e
f
i
x
] = "
[
#
{
t
e
n
a
n
t
_
w
i
t
h
_
e
n
v
i
r
o
n
m
e
n
t
}
]
[
E
R
R
O
R
]
"
e
n
d
e
n
d
p
r
i
v
a
t
e
d
e
f c
u
r
r
e
n
t
_
t
e
n
a
n
t
:
:
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
.
u
p
c
a
s
e
e
n
d
e
n
d
e
n
d
Examples:
[
T
E
N
A
N
T O
N
E
]
[
E
R
R
O
R
] E
r
r
o
r m
e
s
s
a
g
e
[
T
E
N
A
N
T O
N
E S
T
A
G
I
N
G
]
[
E
R
R
O
R
] E
r
r
o
r m
e
s
s
a
g
e
[
T
E
N
A
N
T T
W
O
]
[
E
R
R
O
R
] O
t
h
e
r e
r
r
o
r

View Slide

Content specialization

View Slide

Internationalization — locale les
e
n
:
t
e
n
a
n
t
1
:
h
e
l
l
o
: '
H
e
l
l
o t
e
n
a
n
t
1
'
o
t
h
e
r
:
b
y
e
: '
G
o
o
d
b
y
e
'
h
e
l
l
o
: '
H
e
l
l
o
'

View Slide

Internationalization — i18n backend
m
o
d
u
l
e I
1
8
n
m
o
d
u
l
e B
a
c
k
e
n
d
c
l
a
s
s M
u
l
t
i
t
e
n
a
n
t < S
i
m
p
l
e
d
e
f l
o
o
k
u
p
(
l
o
c
a
l
e
, k
e
y
, s
c
o
p
e
, o
p
t
i
o
n
s
)
t
e
n
a
n
t
_
s
c
o
p
e = [
c
u
r
r
e
n
t
_
t
e
n
a
n
t
] + [
s
c
o
p
e
]
.
f
l
a
t
t
e
n
s
u
p
e
r
(
l
o
c
a
l
e
, k
e
y
, t
e
n
a
n
t
_
s
c
o
p
e
, o
p
t
i
o
n
s
)
e
n
d
p
r
i
v
a
t
e
d
e
f c
u
r
r
e
n
t
_
t
e
n
a
n
t
:
:
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
e
n
d
e
n
d
e
n
d
e
n
d

View Slide

Internationalization — i18n backend
r
e
q
u
i
r
e '
i
1
8
n
/
b
a
c
k
e
n
d
/
m
u
l
t
i
t
e
n
a
n
t
'
I
1
8
n
.
b
a
c
k
e
n
d =
I
1
8
n
:
:
B
a
c
k
e
n
d
:
:
C
h
a
i
n
.
n
e
w
(
I
1
8
n
:
:
B
a
c
k
e
n
d
:
:
M
u
l
t
i
t
e
n
a
n
t
.
n
e
w
,
I
1
8
n
.
b
a
c
k
e
n
d
)

View Slide

Custom views
c
l
a
s
s A
p
p
l
i
c
a
t
i
o
n
C
o
n
t
r
o
l
l
e
r
b
e
f
o
r
e
_
a
c
t
i
o
n :
p
r
e
p
e
n
d
_
t
e
n
a
n
t
_
v
i
e
w
_
p
a
t
h
p
r
i
v
a
t
e
d
e
f p
r
e
p
e
n
d
_
t
e
n
a
n
t
_
v
i
e
w
_
p
a
t
h
t
e
n
a
n
t = A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
p
r
e
p
e
n
d
_
v
i
e
w
_
p
a
t
h R
a
i
l
s
.
r
o
o
t
.
j
o
i
n
(
'
a
p
p
'
, '
v
i
e
w
s
'
, t
e
n
a
n
t
)
e
n
d
e
n
d

View Slide

Custom view example
r
e
n
d
e
r '
h
o
m
e
/
l
e
g
a
l
'
$ l
s a
p
p
/
v
i
e
w
s
/
*
/
h
o
m
e
a
p
p
/
v
i
e
w
s
/
t
e
n
a
n
t
1
/
h
o
m
e
:
l
e
g
a
l
.
h
t
m
l
.
e
r
b
a
p
p
/
v
i
e
w
s
/
t
e
n
a
n
t
2
/
h
o
m
e
:
l
e
g
a
l
.
h
t
m
l
.
e
r
b

View Slide

Custom design

View Slide

Custom design
Layout:
<
%
= s
t
y
l
e
s
h
e
e
t
_
l
i
n
k
_
t
a
g A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t %
>
t
e
n
a
n
t
1
.
c
s
s
:
/
*
*
= r
e
q
u
i
r
e .
/
t
e
n
a
n
t
1
/
m
a
i
n
*
/
t
e
n
a
n
t
1
/
m
a
i
n
.
s
c
s
s
:
@
i
m
p
o
r
t "
.
.
/
s
h
a
r
e
d
/
f
o
n
t
-
l
a
t
o
"
;
@
i
m
p
o
r
t "
v
a
r
i
a
b
l
e
s
"
;
@
i
m
p
o
r
t "
.
.
/
a
p
p
l
i
c
a
t
i
o
n
/
m
a
i
n
"
;
@
i
m
p
o
r
t "
i
m
a
g
e
s
"
;

View Slide

$ t
r
e
e a
p
p
/
a
s
s
e
t
s
/
s
t
y
l
e
s
h
e
e
t
s
a
p
p
/
a
s
s
e
t
s
/
s
t
y
l
e
s
h
e
e
t
s
├── a
p
p
l
i
c
a
t
i
o
n
│ ├── a
d
m
i
n
│ │ └── .
.
.
│ ├── m
a
i
n
.
s
c
s
s
│ └── .
.
.
├── e
m
b
e
d
│ └── m
a
i
n
.
s
c
s
s
├── m
o
b
i
l
e
│ ├── m
a
i
n
.
s
c
s
s
│ └── .
.
.
├── t
e
n
a
n
t
1
│ ├── e
m
b
e
d
.
s
c
s
s
│ ├── f
o
n
t
-
l
a
t
o
.
s
c
s
s
│ ├── i
m
a
g
e
s
.
s
c
s
s
│ ├── m
a
i
n
.
s
c
s
s
│ ├── m
o
b
i
l
e
.
s
c
s
s
│ └── _
v
a
r
i
a
b
l
e
s
.
s
c
s
s
├── t
e
n
a
n
t
1
.
c
s
s
├── t
e
n
a
n
t
1
_
e
m
b
e
d
.
c
s
s
├── t
e
n
a
n
t
1
_
m
o
b
i
l
e
.
c
s
s
├── s
h
a
r
e
d
│ └── f
o
n
t
-
l
a
t
o
.
s
c
s
s
└── .
.
.

View Slide

Cache

View Slide

d
e
f a
p
p
_
c
a
c
h
e
(
n
a
m
e = {
}
, o
p
t
i
o
n
s = n
i
l
, &
b
l
o
c
k
)
k
e
y = [
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
, I
1
8
n
.
l
o
c
a
l
e
, n
a
m
e
]
c
a
c
h
e
(
k
e
y
, o
p
t
i
o
n
s
, &
b
l
o
c
k
)
e
n
d

View Slide

Real-world example
m
o
d
u
l
e C
a
c
h
e
H
e
l
p
e
r
d
e
f a
p
p
_
c
a
c
h
e
(
n
a
m
e = {
}
, o
p
t
i
o
n
s = n
i
l
, &
b
l
o
c
k
)
c
a
c
h
e
(
[
A
p
a
r
t
m
e
n
t
:
:
T
e
n
a
n
t
.
c
u
r
r
e
n
t
,
I
1
8
n
.
l
o
c
a
l
e
,
d
e
v
i
c
e
_
c
a
c
h
e
_
k
e
y
,
c
u
r
r
e
n
t
_
a
c
c
o
u
n
t
.
t
r
y
(
:
r
o
l
e
s
_
c
a
c
h
e
_
k
e
y
)
,
n
a
m
e
]
.
f
l
a
t
t
e
n
(
1
)
, o
p
t
i
o
n
s
, &
b
l
o
c
k
)
e
n
d
d
e
f d
e
v
i
c
e
_
c
a
c
h
e
_
k
e
y
[
d
e
v
i
c
e
_
r
e
q
u
i
r
e
s
_
u
s
e
r
_
a
c
t
i
o
n
_
t
o
_
p
l
a
y
?
]
.
i
n
d
e
x
{ |
v
e
r
s
i
o
n
| v
e
r
s
i
o
n }
e
n
d
d
e
f m
o
d
e
l
_
i
s
_
o
r
_
b
e
l
o
n
g
s
_
t
o
_
c
u
r
r
e
n
t
_
u
s
e
r
?
(
m
o
d
e
l
)
i
f c
u
r
r
e
n
t
_
u
s
e
r
m
o
d
e
l =
= c
u
r
r
e
n
t
_
u
s
e
r |
| m
o
d
e
l
.
t
r
y
(
:
u
s
e
r
) =
= c
u
r
r
e
n
t
_
u
s
e
r
e
n
d
e
n
d
e
n
d

View Slide

Thank you

View Slide

Multi-tenancy with Rails

Multi-tenancy with Rails

Dimiter Petrov

More Decks by Dimiter Petrov

Other Decks in Programming

Featured

Transcript