This section explains how to configure Oracle REST Data Services for connecting to multiple databases for routing requests, and it refers to other documentation sources for other configuration information.
Note:
Oracle REST Data Services must be restarted after making configuration changes. See your application server documentation for information on how to restart applications.
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Oracle REST Data Services supports the ability to connect to more than one database. This section describes different strategies for routing requests to the appropriate database.
Topics:
Oracle REST Data Services supports a number of different strategies for routing requests to the appropriate database. All of these strategies rely on examining the request URL and choosing the database based on some kind of match against the URL. It is useful to recap the pertinent portions of a request URL. Consider the following URL:
https://www.example.com/ords/sales/f?p=1:1
This URL consists of the following sections:
Protocol: https
Host Name: www.example.com
Context Root: /ords
The context root is the location at which Oracle REST Data Services is deployed on the application server.
Request Path: /sales/f?p=1.1
This is the portion of the request URL relative to the context root.
For different applications, it may be important to route requests based on certain prefixes in the request path or certain prefixes in the full request URL.
There are two steps to configuring multiple databases:
Configuring the database connection information
Configuring which requests are routed to which database
When you first configure Oracle REST Data Services, you configure a default database connection named: apex
. You can create additional database connections using the setup
command.
Tip:
To see full help for the setup
command type:
java -jar ords.war help setup
To create a database connection type the following:
java -jar ords.war setup --database <database name>
Where:
<database name>
is the name you want to give the database connection.
You are prompted to enter the information required to configure the database. After you have configured the additional databases, define the rules for how requests are routed to the appropriate database.
You create request routing rules using the map-url
command.
Tip:
To see full help for the map-url
command type:
java -jar ords.war help map-url
If you want to route requests based just on matching a prefix in the request path portion of the URL, use the map-url
command as follows:
java -jar ords.war map-url --type base-path --workspace-id <workspace name> <path prefix> <database name>
Where:
<workspace name>
is the name of the Oracle Application Express workspace where RESTful services for this connection are defined. This may be omitted if RESTful Services are not being used.
<path prefix>
is the prefix that must occur at the start of the request path.
<database name>
is the name of the database connection configured in the previous step.
Related Topics
Assuming Oracle REST Data Services is deployed on a system named example.com
at the context path /ords
, then create the following rule:
java -jar ords.war map-url --type base-path --workspace-id sales_rest /sales sales_db
This rule means that any requests matching https://example.com/ords/sales/...
are routed to the sales_db
database connection. The sales_rest
workspace defined within the sales_db
database is searched for RESTful Services definitions.
The previous rule matches all of the following requests:
https://example.com/ords/sales/f?p=1:1
https://example.com/ords/sales/leads/
https://www.example.com/ords/sales/forecasting.report?month=jan (If www.example.com resolves to the same system as example.com.)
The previous rule does not match of any of the following requests:
http://example.com/ords/sales/f?p=1:1 (The protocol is wrong.) https://example.com:8080/ords/sales/f?p=1:1 (The port is wrong: 443 is default for https, but don't specify if using default.) https://example.com/ords/f?p=1:1 (Missing the /sales prefix.) https://example.com/pls/sales/leads/ (The context path is wrong.)
If you want to route requests based on a match of the request URL prefix, use the map-url
command as follows:
java -jar ords.war map-url --type base-url --workspace-id <workspace name> <url prefix> <database name>
Where:
<workspace name>
is the name of the Oracle Application Express workspace where RESTful services for this connection are defined. This may be omitted if RESTful Services are not being used.
<url prefix>
is the prefix with which the request URL must start.
<database name>
is the name of the database connection.
Assuming Oracle REST Data Services is deployed on a system named example.com
at the context path /ords
, then create the following rule:
java -jar ords.war map-url --type base-url --workspace-id sales_rest https://example.com/ords/sales sales_db
This rule means that any requests matching https://example.com/ords/sales/...
are routed to the sales_db
database connection. The sales_rest
workspace defined within the sales_db
database is searched for RESTful Services definitions.
The previous rule matches all of the following requests:
https://example.com/ords/sales/f?p=1:1 https://example.com/ords/sales/leads/ https://example.com/ords/sales/forecasting.report?month=jan
The previous rule does not match of any of the following requests:
http://example.com/ords/sales/f?p=1:1 (The protocol is wrong.) https://example.com:8080/ords/sales/f?p=1:1 (The port is wrong: 443 is default for https, but don't specify if using default.) https://example.com/ords/f?p=1:1 (Missing the /sales segment of the base URL.) https://example.com/pls/sales/leads/ (The context path is wrong.) https://www.example.com/ords/sales/forecasting.report?month=jan (The host name is wrong.)
This section outlines the installation choices and different scenarios associated with copying and moving pluggable databases introduced by the Oracle Database 12c multitenant architecture with respect to Oracle REST Data Services.
Oracle Database 12c Release 1 (12.1) introduces the multitenant architecture. This database architecture has a multitenant container database (CDB) that includes a root container, CDB$ROOT
, a seed database, PDB$SEED
, and multiple pluggable databases (PDBs). A PDB appears to users and applications as if it were a non-CDB. Each PDB is equivalent to a separate database instance in Oracle Database Release 11g.
The root container, CDB$ROOT
, holds common objects that are accessible to every PDB utilizing metadata links or object links. The seed database, PDB$SEED
, is used when creating a new PDB to seed the new pluggable database. The key benefit of the Oracle Database 12c multitenant architecture is that the database resources, such as CPU and memory, can be shared across all of the PDBs. This architecture also enables many databases to be treated as one for tasks such as upgrades or patches, and backups.
You can install Oracle REST Data Services into one or more pluggable databases PDBs in a multitenant database or into the container database (CDB). The installation choices are as follows:
If you want the same version of Oracle REST Data Services available in all the PDBs, then install it into the CDB. The rest of the instructions in this topic refer to installing into the CDB.
If you want only some PDBs to be able to use Oracle REST Data Services, or if you want different PDBs to use different versions of Oracle REST Data Services, then install into the desired PDBs. (Use the same procedure as for a non-CDB.)
When Oracle REST Data Services is installed into a CDB, it is installed in the root container, the seed container, and any existing PDBs. The root container (CDB$ROOT
) includes the ORDS_METADATA schema to store the common database objects for Oracle REST Data Services packages, functions, procedures, and views. It also includes the Oracle REST Data Services public user (ORDS_PUBLIC_USER).
The seed container (PDB$SEED
) includes the ORDS_METADATA schema and the Oracle REST Data Services public user. You can create a new PDB by copying PDB$SEED
and creating metadata links back to the common database objects in the ORDS_METADATA schema within the CDB$ROOT
. As a result, there are multiple copies of the Oracle REST Data Services tables and only single copies of the Oracle REST Data Services packages, functions, procedures, and views. Thus, each PDB has the ORDS_METADATA schema and its own copy of the Oracle REST Data Services tables, so that it can hold the metadata for the Oracle REST Data Services application within that PDB. Each PDB also has its own Oracle REST Data Services public user.
See also "Creating a PDB using the Seed" in Oracle Database Administrator's Guide.)
If you want to have all PDBs in a multitenant environment to use the same Oracle REST Data Services release and patch set, install into the CDB. (This option will not allow you to have different releases of Oracle REST Data Services in different PDBs.)
Before installing into the a CDB:
Ensure that the PDBs are open (not mounted/closed) in read/write mode (except for PDB$SEED
, which remains in read-only mode). See "Modifying the Open Mode of PDBs" in Oracle Database Administrator's Guide.
Ensure that the default and temporary tablespaces to be used by the ORDS_METADATA schema and the ORDS_PUBLIC_USER user exist and that you know the tablespace names. The installation procedure creates those users, but it does not create the tablespaces.
Note that ORDS_METADATA and ORDS_PUBLIC_USER are also installed in the seed container, and that the default and temporary tables will have to exist in PDB$SEED
. If these tablespace do not already exist there, then you will have to create the tablespaces in PDB$SEED
; see "Running Oracle-Supplied SQL Scripts in a CDB" in Oracle Database Administrator's Guide.
To install Oracle REST Data Services into a CDB, follow these steps.
Go to the folder into which you unzipped the Oracle REST Data Services installation kit.
Enter the following command:
java -jar ords.war install advanced
Note:
To use the pluggable mapping feature, see Making All PDBs Addressable by Oracle REST Data Services (Pluggable Mapping).
When prompted, enter the database connection information for your CDB:
Enter the name of the database server [localhost]: Enter the database listen port [1521]: Enter 1 to specify the database service name, or 2 to specify the database SID [1]: Enter the database service name: (for example, cdb.example.com)
Verify the Oracle REST Data Services installation:
Enter 1 if you want to verify/install Oracle REST Data Services schema or 2 to skip this step [1]:
Accept or enter 1 (the default) to install Oracle REST Data Services into the CDB and all of its PDBs.
Enter and confirm the ORDS_PUBLIC_USER password:
Enter the database password for ORDS_PUBLIC_USER: Confirm password:
When prompted, enter additional information as needed. (See Advanced Installation Using Command-Line Prompts.)
Related Topics
When you use a new release of Oracle REST Data Services, upgrading its schema in the CDB and its pluggable databases (PDBs) will occur automatically when you perform a simple or advanced installation.
For example:
java -jar ords.war
If Oracle REST Data Services is already installed or upgraded, a message displays the Oracle REST Data Services schema version, and you will not be prompted for information.
If an error occurred, view the log files.
Pluggable mapping refers to the ability to make all PDBs in a CDB addressable by Oracle REST Data Services. To use this feature, follow the instructions in this topic.
If the Oracle REST Data Services configuration file includes the db.serviceNameSuffix
parameter, this indicates that the Oracle REST Data Services pool points to a CDB, and that the PDBs connected to that CDB should be made addressable by Oracle REST Data Services.
The value of the db.serviceNameSuffix
parameter must match the value of the DB_DOMAIN
database initialization parameter, and it must start with a period (.). To set the value of the db.serviceNameSuffix
parameter:
In SQL*Plus, connect to the root as a user with SYSDBA privileges.
Check the value of the DB_DOMAIN
database initialization parameter.
SQL> show parameter DB_DOMAIN
Exit SQL*Plus.
SQL> exit
If the DB_DOMAIN
value was not empty, then on the command line enter the command to create the key and value for the db.serviceNameSuffix
parameter and its DB_DOMAIN
. This will be used to add this entry to the Oracle REST Data Services configuration file.
echo db.serviceNameSuffix=.value-of-DB_DOMAIN > snsuffix.properties
For example, if DB_DOMAIN
is set to example.com
, enter the following:
echo db.serviceNameSuffix=.example.com > snsuffix.properties
If the db.serviceNameSuffix
parameter value is not defined, enter a command in the following format to add an entry to the configuration file:
java -jar ords.war set-properties --conf pool-name snsuffix.properties
Where pool-name is one of the following:
poolName
for a PL/SQL Gateway configuration
poolName_pu
for an Oracle REST Data Services RESTful Services configuration
poolName_rt
for an Application Express RESTful Services configuration
Example 1: You want to make PDBs in a CDB addressable globally. Specify defaults
by entering the following command:
java -jar ords.war set-properties --conf defaults snsuffix.properties
Note:
The approach shown in Example 1 (setting the property for all pools through the defaults.xml
file) is best for most use cases.
Example 2: You want to make PDBs in a CDB addressable for your PL/SQL Gateway, and your pool name is apex
. Enter the following command:
java -jar ords.war set-properties --conf apex snsuffix.properties
For example, if the database pointed to by apex has a DB_DOMAIN
value of example.com
and contains the two PDBs pdb1.example.com
and pdb2.example.com
, the first PDB will be mapped to URLs whose path starts with /ords/pdb1/
, and the second PDB will be mapped to URLs whose path starts with /ords/pdb2/
.
Example 3: You want to make PDBs in a CDB addressable for your Oracle REST Data Services RESTful Services, and your pool name is apex_pu
. Enter the following command:
java -jar ords.war set-properties --conf apex_pu snsuffix.properties
Example 4: You want to make PDBs in a CDB addressable for your Application Express RESTful Services and your pool name is apex_rt
. Enter the following command:
java -jar ords.war set-properties --conf apex_rt snsuffix.properties
Related Topics
Oracle REST Data Services support the Fast Connection Failover (FCF) feature of Oracle Real Application Clusters (Oracle RAC).
Oracle REST Data Services runs with the Universal Connection Pool (UCP) in all the Application Server environments that it supports, such as WebLogic, Tomcat, GlassFish. UCP in turn supports Fast Connection Failover . To enable FCF, Oracle Notification Service (ONS) must to be enabled. To enable ONS, add entries to the list of properties in the Oracle REST Data Services defaults.xml
configuration file as shown in the following code snippet:
<entry key="jdbc.enableONS">true</entry> <entry key= "jdbc.ONSConfig">nodes=racnode1:4200,racnode2:4200\nwalletfile=/oracle11/onswalletfile</entry>
<entry key="db.connectionType">customurl</entry> <entry key="db.customURL">jdbc:oracle:thin:@(DESCRIPTION=(FAILOVER=ON)(ADDRESS_LIST= (LOAD_BALANCE=ON)(ADDRESS=(PROTOCOL=TCP)(HOST=prod_scan.example.com)(PORT=1521))) (CONNECT_DATA=(SERVICE_NAME=ISPRD)))|</entry>
After updating the defaults.xml
configuration file, Oracle REST Data Services need to be restarted for the changes to take effect.
Unplanned outages: When RAC detects an instance failure, it generates a FAN Down event which FCF picks up. FCF then terminates all connections to the failed instance and directs all future requests to the surviving RAC instances.
Planned outages: For instance, when a Database Administrator (DBA) wants to gracefully shut down a RAC instance for performing some maintenance activity. The instance shutdown generates a FAN Planned Down event which FCF picks up. FCF then directs all new requests to other RAC instances and drains or allows currently active transactions to complete.
Note:
Long running transactions may need to be terminated forcefully.To configure security, caching, pre- and post- processing, environment, and Excel settings, see Using SQL Developer Oracle REST Data Services Administration (Optional).
This section explains how to configure the REST- Enabled SQL service.
Note:
Enabling the REST- Enabled SQL service enables authentication against the Oracle REST Data Service enabled database schemas. This makes the database schemas accessible over HTTPS, using the database password. Oracle highly recommends that you provide strong secure database passwordsLocate the folder where the Oracle REST Data Services configuration file is stored.
Open the defaults.xml
file and add: <entry key="restEnabledSql.active">true</entry>
.
Save the file.
Restart Oracle REST Data Services.
Locate the folder where the Oracle REST Data Services configuration file is stored.
Open the defaults.xml
file and update the value of the misc.pagination.maxRows
parameter:<entry key=”misc.pagination.maxRows”>1500</entry>
Note:
The default value formisc.pagination.maxRows
is 500.Save the file.
Restart Oracle REST Data Services.
This section explains how to configure a custom error page instead of the error page generated by Oracle REST Data Services.
To configure a custom error page, perform the following steps:
Locate the folder where the Oracle REST Data Services configuration file is stored.
Open the defaults.xml
file and update the value of the error.externalPath
parameter:
<entry key=”error.externalPath">/path/to/error/pages/folder/</entry>
Where:
/path/to/error/pages/folder
is the path to a folder containing files that define the error pages. The files are stored in {status}.html
format.
Where, {status}
is the HTTP status code for which you want to create a custom error page.
Save the file.
Restart Oracle REST Data Services.
Example 2-1 Configuring custom error page for “HTTP 404” status code
To configure a custom error page for the “HTTP 404 – Not Found” status, perform the following steps:
Create a file named 404.html
.
Save it under /usr/local/share/ords/error-pages/
folder.
Configure the error.externalPath
parameter to point to /usr/local/share/ords/errro-pages/
folder.
Save the file.
Restart Oracle REST Data Services.
For more information on how to develop RESTful Services for use with Oracle REST Data Services, see Developing Oracle REST Data Services Applications.