americas pug challenge openedge abl multi-tenancy mary székely openedge fellow may 2012
TRANSCRIPT
Americas PUG Challenge
OpenEdge ABL Multi-tenancy
Mary SzékelyOpenEdge FellowMay
2012
© 2012 Progress Software Corporation. All rights reserved.2
Introduction
Regular Tenant Programming Model
Super-tenant Programming Model
AppServer and Client-Principal
Questions
Agenda
© 2012 Progress Software Corporation. All rights reserved.3
A tenant is a separate organizational entity within a multi-tenant database with • It’s own private data segment for each multi-tenant table
– Except for groups and Super-tenants• One or more ABL security domains• Its own users
Each multi-tenant database user belongs to some domain and hence some type of tenant
Multi-Tenant Database
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User logging in with no domain association• Belongs to the “blank” domain and normally has access as the
“default” type of tenant
User logging in as a member of a domain that is not blank and not associated with a Super-tenant • Has access as a “regular” type of tenant
User logging in as a member of a domain that is associated with a “super” tenant • Is not a normal tenant user because he has no data segments of
his own but can get temporary access to regular tenant data.
Multi-Tenant Users, Domains and Tenants
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All users can access non-Multi-tenant (shared ) data as usual.• Schema tables and temp-tables are always shared
Regular tenant users and Default tenant users • Can access the private data segments of multi-tenant tables owned
by that tenant– Access is subject to the user’s normal access rights
• Cannot access the private segments of any other tenants
Super-tenant users• Cannot access regular tenant data unless the Super-tenant user
uses new ABL language elements– New SET-EFFECTIVE-TENANT and TENANT-WHERE constructs allow
temporary access to regular tenant data– Access is still subject to the Super-tenant user’s normal access rights
Multi-Tenant Database Users Access to Tenants
© 2012 Progress Software Corporation. All rights reserved.6
Simple Multi-Tenant and Shared Data
Tenancy Layer
HomeDepot
Lowes
Default deallocated, or newly migrated data
Shared_file _field _tenant
State
……
Customers
Orders
Items …
Customers
Orders
Items …
Data Access for 2 tenants, HomeDepot and Lowes
© 2012 Progress Software Corporation. All rights reserved.7
HomeDepot | access-cd | appauth |HomeDepot
_sec-authentication-domain
_sec-authentication-system
_tenant
Lowes | access-cd | appauth | Lowes
“” | “” |_oeusertable| Default
_oeusertable (_user)
appauth Applugin.p
HomeDepot | 1
Lowes | 2
Default | 0
An OpenEdge Tool creates a Tenant by providing:• A record in the _tenant schema table• A related record in the _sec-authentication-domain• New in 11.1, the _sec_authentication-system table can
have user ABL .p or .cls authentication plugins
Meta Schema for Domains and Tenants in the database
© 2012 Progress Software Corporation. All rights reserved.8
Users
Suzi HomeDepotAllen HomeDepotCat HomeDepot
Rich HomeDepot
Rich LowesJohn Lowes
Claudio LowesLouie Lowes
edwardjames
Domains
name tenant
HomeDepot HomeDepot
name tenant
Lowes Lowes
name tenant
blank Default
Data
Tenancy Layer
HomeDepot
Lowes
Default deallocated or migrated data
Shared
Customers
Orders
Items …
_file _field _tenant
state ……
Customers
Orders
Items …
Users Are Granted Access to Tenants by Domains
© 2012 Progress Software Corporation. All rights reserved.9
The CLIENT-PRINCIPAL is an ABL built-in object with methods similar to SETUSERID
Getting a domain using SETUSERID (obsolete):
IF NOT SETUSERID(“rich@homedepot”,encoded_password)THEN error…
Getting the same domain using CLIENT-PRINCIPAL:
CREATE CLIENT-PRINCIPAL hCP.hCP:INITIALIZE(“rich@homedepot”,?,?,encoded_password).IF NOT SET-DB-CLIENT(hCP,dbname)THEN error… SEAL the CLIENT-PRINCIPAL or NOT??
Using a CLIENT-PRINCIPAL to get to a Domain
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BEST security• Use SET-DB-CLIENT() or SECURITY-POLICY:SET-CLIENT()• 11.1+ : configurable server-side ABL plug-in which results in a sealed
CLIENT-PRINCIPAL with no domain access code outside database• 11.0+:configurable _USER and _OSlocal plug-in
BETTER security• Use SET-DB-CLIENT() or SECURITY-POLICY:SET-CLIENT()• Client ABL creates/seals CLIENT-PRINCIPAL and SSO to database• Requires secure r-code with domain access code outside database
OK security• Use SETUSERID()• Not extensible – no more enhancements• Continue to use in data servers (for now )• Do replace for OpenEdge 11.x RDBMS
11.x uses CLIENT-PRINCIPALs to Manage Users and their access to Tenant data
© 2012 Progress Software Corporation. All rights reserved.11
Introduction
Regular Tenant Programming Model
Super-Tenant Programming Model
AppServer and Client-Principal
Questions
Agenda
© 2012 Progress Software Corporation. All rights reserved.12
The same pcode and rcode can serve for all Regular tenants
No special ABL coding is required for a regular tenant user to access a multi-tenant table• Legacy code only needs recompile in version 11+ to be run as
multi-tenant code by a regular tenant user
The ABL compiler does not need to know • What tenant will be executing the rcode it is compiling• Whether the rcode will be run on multi-tenant tables or not
– or even on a multi-tenant enabled database or not
The ABL rcode that accesses a multi-tenant table • Is mapped at runtime to the appropriate tenant’s data segment
Each regular tenant’s ABL rcode is identical• But the data accessed is different
© 2012 Progress Software Corporation. All rights reserved.13
1 Fred Smith
2 Joan Adlon 3 George Holmes
Lowes
1 Albert Hall
2 Candace Jones
3 Carrie Abrahm
HomeDepot
Customer Customer
Regular tenant ABL
For two tenants, HomeDepot and Lowes, you will get a different report from the same rcode
FOR EACH Customer: DISPLAY CustNum Name.END.
© 2012 Progress Software Corporation. All rights reserved.14
FIND FIRST Customer. /*automatically gets the right tenant*/DISPLAY CustNum Name.
4 New CustLowes
4 New CustHomeDepot
CREATE Customer. /*automatically goes to the right tenant*/Name = “New Cust”DISPLAY CustNum Name.
1 Albert HallHomeDepot
1 Fred Smith Lowes
Regular tenant ABL
© 2012 Progress Software Corporation. All rights reserved.15
1 Fred Smith
2 Joan Adlon 3 George Holmes
Lowes
1 Albert Hall
2 Candace Jones
3 Carrie Abrahm
HomeDepot
Customer
Sequences - Multi-tenant
If the sequence is multi-tenant, it will increment independently in each tenant
For the two tenants in our hardware application, the custNums from a MT sequence:• Start with 1 for each tenant• Are non-unique across tenants• Ideal for use where any join tables have
the same tenancy type
© 2012 Progress Software Corporation. All rights reserved.16
1 Fred Smith
3 Joan Adlon 4 George Holmes
Lowes
2 Albert Hall
5 Candace Jones
6 Carrie Abrahm
HomeDepot
Customer
Sequences – shared across tenants
For the same database, the custNum from a shared or non-multi-tenant sequence will number consecutively across tenants
The custNum therefore is unique across all tenants (only 1 Cust 4)
Why would you ever want this?FOR EACH Customer, EACH Order of Customer.• If the Order table is shared, then the
Order.CustNum would be non-unique and useless (e.g. 2 Cust 4’s) unless the CustNum sequence is shared.
© 2012 Progress Software Corporation. All rights reserved.17
1 Fred Smith
2 Joan Adlon 3 George Holmes
Lowes
1 Albert Hall
2 Candace Jones
3 Carrie Abrahm
HomeDepot
Customer Customer
LowesHomeDepot
TENANT-ID() and TENANT-NAME()
These two functions:• Return the current session tenant Id and Name. • Take an optional Dbname parameter if there is more than one
database in the session
DISPLAY TENANT-NAME(). FOR EACH Customer: DISPLAY CustNum Name.END.
© 2012 Progress Software Corporation. All rights reserved.18
Regular tenant code might use these two functions to:• Display the current session tenant information in a report• Populate a column in a temp-table• Populate a multi-tenant table column to make its foreign key unique
Regular tenant code may not use these two functions in a WHERE clause: /* NOT OKAY TO DO THIS!!! */ FOR EACH Customer WHERE TENANT-NAME() = “Lowes”:
• The ABL already knows what tenant a regular tenant belongs to– And there is no “hidden” column in any table or index that can be used to
select on in a regular tenant WHERE clause.• Because tenants are like mini-databases, it is equivalent to saying:
/* NOT OKAY TO DO THIS!!! */ FOR EACH Customer WHERE DBNAME = “Sports”:
TENANT-ID() and TENANT-NAME() contd
© 2012 Progress Software Corporation. All rights reserved.19
1 Shovel bos
3 Extension cable bos 4 Hammer ny 7 Green Paint bos 8 Faucet ny 9 Lamp bos
LowesBOSAndLowesNY, as GROUP LowesItm
2 Lawn Mower
5 Screw Driver
6 Table
HomeDepot
Item
Item
A DB has 3 tenants, HomeDepot, LowesNY and LowesBos LowesNY and LowesBos are in the same group for Items
FOR EACH Item: DISPLAY ItemNum Item-Desc.END.
Groups of tenants (only tables have groups)
© 2012 Progress Software Corporation. All rights reserved.20
Tenancy Layer
HomeDepot
LowesBos
LowesNy
LowesItm Group
Default deallocated, or recently migrated data
Shared_file _field _tenant
State…
…
Customers
Orders
Items for both LowesBos and Ny
…
Customers
Orders Items …
Orders
Customers
…
Data Access for 3 tenants, HomeDepot and LowesBos, LowesNy and 1 Item table group
© 2012 Progress Software Corporation. All rights reserved.21
Within a Group, there is no individual tenancy inherent in each record
A user of any tenant in a group can create, read and update any row in the table that is grouped • Therefore there is no one tenant owner for a group record
BUFFER-GROUP-ID and BUFFER-GROUP-NAME functions and buffer methods provide group information for a buffer
You must use shared sequences for unique indexes with groups
LowesBOSAndLowesNY, as GROUP LowesItm
Item
1 Shovel bos
3 Extension cable bos 4 Hammer ny 7 Green Paint bos 8 Faucet ny 9 Lamp bos
© 2012 Progress Software Corporation. All rights reserved.22
Introduction
Regular Tenant Programming Model
Super-tenant Programming Model
AppServer and Client-Principal
Questions
Agenda
© 2012 Progress Software Corporation. All rights reserved.23
Why are Super-tenants needed?
Super-tenants exist to allow housekeeping cross-tenant tasks such as • Saas administration i.e. billing, moving tenants..• Migration from previous database versions• Utilities where simultaneous access to multiple tenant’s data is
required
Super-tenants have no data of their own
Super-tenants have special ABL to allow them to:• Get access to regular tenant data• Execute legacy code
© 2012 Progress Software Corporation. All rights reserved.24
1 Albert HallHomeDepot
SET-EFFECTIVE-TENANT function
Available only to a Super-tenant user Allows a Super-tenant user to act on behalf of a regular tenant
• So you don’t have to SETUSERID or SET-DB-CLIENT to actually become a real user of that tenant
SET-EFFECTIVE-TENANT(“HomeDepot”).FIND FIRST Customer.DISPLAY CustNum Name.RUN myCustApp.p etc.
All FINDs,CREATEs,DELETEs,FOR EACHs, all ABL will use HomeDepot indexes and access HomeDepot tenant records
© 2012 Progress Software Corporation. All rights reserved.25
BUFFER-TENANT-ID() and BUFFER-TENANT-NAME functions and buffer-handle methods
These two functions are also analogous to TENANT-ID() and TENANT-NAME()• But are used by Super-tenant users with a buffer
– since the session’s tenant-id and name are for the Super-tenant not the buffer.
The buffer must be populated, or they return UNKNOWN. For Example:
SET-EFFECTIVE-TENANT(“HomeDepot”).FIND FIRST Customer.BUFFER-TENANT-NAME(Customer) /* returns HomeDepot */
These two functions/methods when applied to a group record:• Sometimes return an arbitrary member of the group• Usually return the effective-tenant if it is a member of the group
© 2012 Progress Software Corporation. All rights reserved.26
2 1 Fred Smith
2 2 Joan Adlon 2 3 George
Lowes
1 1 Albert Hall
1 2 Candace
1 3 Carrie
HomeDepot
Customer
Using _tenant schema table to scan across tenants
FOR EACH _Tenant WHERE _Tenant-Name < “M”: SET-EFFECTIVE-TENANT(_Tenant._TenantId). FOR EACH Customer: DISPLAY BUFFER-TENANT-ID(Cust) CustNum Name. RUN myCustApplication.p(CustNum). END.END.
© 2012 Progress Software Corporation. All rights reserved.27
Using TENANT-WHERE to scan across tenants
2 1 Fred Smith
2 2 Joan Adlon 2 3 George
Lowes
1 1 Albert Hall
1 2 Candace
1 3 Carrie
HomeDepot
Customer
FOR EACH Customer TENANT-WHERE TENANT-NAME() < “M”: SET-EFFECTIVE-TENANT(BUFFER-TENANT-ID(Cust)). DISPLAY BUFFER-TENANT-ID(Cust) CustNum Name. RUN myCustApplication.p(CustNum).END.
© 2012 Progress Software Corporation. All rights reserved.28
TENANT-WHERE with Sorting may be Slow
Default order is by _tenant, overrideable by using a BY phrase
FOR EACH Customer TENANT-WHERE TENANT-ID() > 0 BY BUFFER-TENANT-NAME(Customer) BY Customer.Name: SET-EFFECTIVE-TENANT(BUFFER-TENANT-ID(Customer)). Etc.End.
Sorting will be slow, across all _tenants. It would be better to use the nested form which can take advantage of indexing.
FOR EACH _tenant WHERE _tenant._tenantId > 0 BY _tenant._tenant-name: SET-EFFECTIVE-TENANT(_tenant._tenantId). FOR EACH Customer BY Customer.Name: Etc. END.END.
© 2012 Progress Software Corporation. All rights reserved.29
TENANT-WHERE with Joins
Only 1 level of join can have the TENANT-WHERE phrase
The AVM automatically propagates the current tenancy to lower levels of join, where appropriate• So the join will contain records from the same tenant throughout the
current tenant iteration
FOR EACH Customer TENANT-WHERE TENANT-ID() > 0, EACH Order of Customer, EACH Order-line of Order.
© 2012 Progress Software Corporation. All rights reserved.30
Multi-Tenant and Shared Data
Tenancy Layer
HomeDepot
Lowes
Default
Shared _file _field _tenant
State …
…
Customers
Orders
Items …
Customers
OrdersItems …
Customers
Orders
Items
Super-tenants and Migration
Scenario: • Log in as a Super-tenant user, with
default effective-tenancy. To copy Customers from the default
data segment into the correct tenant:
DEFINE BUFFER bCust FOR Cust.FOR EACH Cust: SET-EFFECTIVE-TENANT(Cust.Ten-name).
CREATE bCust. BUFFER-COPY Cust TO bCust.END.
Afterward, delete default data.
© 2012 Progress Software Corporation. All rights reserved.31
Super-tenants and Migration - note: TRIGGERS
DEFINE BUFFER bCust FOR Cust.
FOR EACH Cust: CREATE bCust FOR TENANT(Cust.Ten-name). /*CREATE triggers?*/ BUFFER-COPY Cust TO bCust. DELETE Cust. /*DELETE TRIGGERS may not work*/END.
BELOW IS BETTER AND SAFER IF THERE ARE TRIGGERS !!
FOR EACH Cust: SET-EFFECTIVE-TENANT(Cust.Ten-name). CREATE bCust. /* CREATE triggers will work fine*/ BUFFER-COPY Cust TO bCust. SET-EFFECTIVE-TENANT(0). DELETE Cust. /* DELETE triggers will work fine*/END.
© 2012 Progress Software Corporation. All rights reserved.32
LowesBOS And LowesNY, as GROUP LowesItm
2 Lawn Mower
5 Screw Driver
6 Table
HomeDepot
LowesBOSAndLowesNY, as GROUP LowesItm
1 Shovel bos
3 Extension cable bos 4 Hammer ny 7 Green Paint bos 8 Faucet ny 9 Lamp bos
1 Shovel bos
3 Extension cable bos 4 Hammer ny 7 Green Paint bos 8 Faucet ny 9 Lamp bos
Super-tenant programming with groups and SKIP-GROUP-DUPLICATES
FOR EACH Item TENANT-WHERE
TENANT-ID() > 0: SET-EFFECTIVE-TENANT (BUFFER-TENANT-ID(Item)). DISPLAY ItemNum Item-Desc.END.
LowesItm group appears twice – once for LowesBos tenant and once for LowesNY
To skip the 2nd LowesItm group use SKIP-GROUP-DUPLICATES
FOR EACH Item TENANT-WHERE TENANT-ID() > 0 SKIP-GROUP-DUPLICATES:
© 2012 Progress Software Corporation. All rights reserved.33
Introduction
Regular Tenant Programming Model
Super-tenant Programming Model
AppServer and Client-Principal
Questions
Agenda
© 2012 Progress Software Corporation. All rights reserved.34
All types of AppServers will need to manage user logins with CLIENT-PRINCIPALS to get correct user auditing, permissions, and tenancy
Stateless, State-free and WebSpeed AppServers in a Multi-tenant environment will need some form of context management of CLIENT-PRINCIPALS because• multiple appserver instances serve the same client “session”
across multiple requests
State-reset, State-aware can optionally use context management to resume user logins that span connections
Everything else works normally for a regular tenant user
AppServer and Regular Multi-tenant Programming
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Has physical storage that• Spans OS processes• Spans multiple AppServers• Spans AppServer starts & stops
Stores raw CLIENT-PRINCIPAL and login session id• Uses login session id as primary index
Has basic operations for• startUserSession (export CLIENT-PRINCIPAL under the session id)• stopUserSession (import CLIENT-PRINCIPAL using session id, delete it)• restoreUserSession (import CLIENT-PRINCIPAL using session id)
Anatomy of a Context Manager
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Using clientContextId for exporting CLIENT-PRINCIPALs
sessionId | cp
mycp table
ajfrbo9kk … | raw data..
lqjdkor71 … | raw data..
Context store
/* new in OpenEdge 11.1 */DEFINE VARIABLE reqInfo AS
Progress.Lang.OERequestInfo.reqInfo = CAST(SESSION:CURRENT-REQUEST-INFO, Progress.Lang.OERequestInfo).
CREATE CLIENT-PRINCIPAL hCP.hCP:SESSION-ID = reqInfo:clientContextId.… SET-DB-CLIENT(hCP) etc etcCREATE mycp. /*new ctx record*/mycp.sessionId = hCP:SESSION-ID.mycp.cp = hCP:EXPORT-PRINCIPAL().DELETE OBJECT hCP.
© 2012 Progress Software Corporation. All rights reserved.37
Using clientContextId for importing CLIENT-PRINCIPALs
sessionId | cp
mycp table
ajfrbo9kk … | raw data..
lqjdkor71 … | raw data..
Context store
/* new in OpenEdge 11.1 */DEFINE VARIABLE reqInfo AS
Progress.Lang.OERequestInfo.reqInfo = CAST(SESSION:CURRENT-REQUEST-INFO, Progress.Lang.OERequestInfo).FIND mycp WHERE mycp.sessionId =
reqInfo:clientContextId NO-ERROR.IF NOT AVAILABLE mycp THEN error…CREATE CLIENT-PRINCIPAL hCP.hCP:IMPORT-PRINCIPAL(mycp.cp).
Ok = SET-DB-CLIENT(hCP).If NOT Ok THEN error… orDELETE mycp …
© 2012 Progress Software Corporation. All rights reserved.38
AppServer context management of CLIENT-PRINCIPALS and tenancy
1. AppServer startup.p procedure :– Capture/create initial database user (such as “blank”) into a CLIENT-
PRINCIPAL to be used later to explicitly reset tenancy to default
2. User login: connect.p or equivalent :– Create and save the CLIENT-PRINCIPAL identity context
3. User logout: disconnect.p or equivalent :– Find and delete the CLIENT-PRINCIPAL identity context
4. Start remote procedure: activate.p (no equivalent ):– Find/receive the CLIENT-PRINCIPAL identity context– Switch user identity contexts from previous to current one– May include saving the context from the previous user
5. End remote procedure: deactivate.p (no equivalent):– Do any optional context and identity cleanup such as resetting
tenancy to the default one set up in startup.p
NOTE: State-reset and state-aware servers do usually not need 4 and 5.
Webspeed,/WebServices/AIA do 2 and 3 without clientContextId
© 2012 Progress Software Corporation. All rights reserved.39
Sample code snippet to create a CLIENT-PRINCIPAL in an AppServer login.p/connect.p
The CONNECT method of the client’s SERVER object allows you to optionally pass the userid, password, and a character string to the AppServer. They become the 3 parameters to the connect.p on the AppServer. This is one of many ways to get your userid@domain and user password to the connect.p.
encrypted_pswd = “oech1::” + audit-policy:encrypt-audit-mac-key(pswd). hServ:CONNECT(“-S nnnn –H hostname”, userid, encrypted_pswd).
DEFINE INPUT PARAMETER user_domain AS CHAR.DEFINE INPUT PARAMETER encryptd_pswd AS CHAR.DEFINE INPUT PARAMETER mychar AS CHAR.
CREATE CLIENT-PRINCIPAL hCP.hCP:INITIALIZE(user_domain,?,?,encrypted_pswd).
© 2012 Progress Software Corporation. All rights reserved.40
AppServer context switching automatically clears buffers and invalidates query index cursors
When AppServer (or any AVM) switches tenant context because its user is changed to be a user of a different tenant , the AVM• clears out all Multi-tenant buffers (temp-tables are not Multi-tenant)• marks all Multi-tenant index cursor scans as invalid
ABL Code to handle a db tenant context switch should proactively• clear buffers and temp-tables• close existing queries and index scans
State-aware and State-reset Appservers switch tenant context per connection • State-reset automatically clears out context
Stateless/State-free Appservers switch tenant context per request Dangerous to use a Super-Tenant and SET-EFFECTIVE-
TENANT on an AppServer since no automatic context clearing happens
© 2012 Progress Software Corporation. All rights reserved.41
Questions ?
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