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Help Center/ MapReduce Service/ Developer Guide (LTS)/ Hive Development Guide (Security Mode)/ More Information/ Interface Reference/ WebHCat

WebHCat

Updated on 2024-08-10 GMT+08:00

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NOTE:

The following uses the service IP address of WebHCat and the WebHCat HTTP port configured during the installation as an example.
You can perform the example operations only after kinit authentication is implemented on the installed client.
The examples of the HTTPS protocol are as follows. To use the HTTP protocol, you need to perform the following operations:
1. Switch the RESTful API to the HTTP protocol. For details, see Configuring HTTPS/HTTP-based REST APIs.
2. Delete --insecure from the example and replace HTTPS with HTTP, for example:
  curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/status'
  
  is changed to
  
  curl -i -u : --negotiate 'http://10.64.35.144:9111/templeton/v1/status'
Before performing the operation, ensure that the curl in use is later than 7.34.0.
You can run the following command to view the curl version:

curl -V

:version(GET)

Description
Queries a list of response types supported by WebHCat.
URL
https://www.myserver.com/templeton/:version

Parameter

Parameter	Description
:version	WebHCat version number. Currently, the version number must be v1.

Returned result

Parameter	Description
responseTypes	List of response types supported by WebHCat.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1'

status (GET)

Description
Obtains the status of the current server.
URL
https://www.myserver.com/templeton/v1/status
Parameter
None

Returned result

Parameter	Description
status	If the WebHCat connection is normal, OK is returned.
version	Character string, including the version number, for example, v1.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/status'

version (GET)

Description
Obtains the WebHCat version of the server.
URL
https://www.myserver.com/templeton/v1/version
Parameter
None

Returned result

Parameter	Description
supportedVersions	All supported versions.
version	WebHCat version of the server.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/version'

version/hive (GET)

Description
Obtains the Hive version of the server.
URL
https://www.myserver.com/templeton/v1/version/hive
Parameter
None

Returned result

Parameter	Description
module	Hive.
version	Hive version.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/version/hive'

version/hadoop (GET)

Description
Obtains the Hadoop version of the server.
URL
https://www.myserver.com/templeton/v1/version/hadoop
Parameter
None

Returned result

Parameter	Description
module	Hadoop.
version	Hadoop version.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/version/hadoop'

ddl (POST)

Description
Executes a DDL statement.
URL
https://www.myserver.com/templeton/v1/ddl

Parameter

Parameter	Description
exec	HCatalog DDL statement to be executed.
group	User group used when DDL is used to create a table.
permissions	Permission used when DDL is used to create a table. The format is rwxr-xr-x.

Returned result

Parameter	Description
stdout	Standard output value during HCatalog execution. The value may be empty.
stderr	Error output during HCatalog execution. The value may be empty.
exitcode	Return value of HCatalog.

Example

curl -i -u : --insecure --negotiate -d exec="show tables" 'https://10.64.35.144:9111/templeton/v1/ddl'

ddl/database (GET)

Description
Lists all databases.
URL
https://www.myserver.com/templeton/v1/ddl/database

Parameter

Parameter	Description
like	Regular expression used to match the database name.

Returned result

Parameter	Description
databases	Database name.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/ddl/database'

ddl/database/:db (GET)

Description
Obtains details about a specified database.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db
Parameter

Parameter

Description

:db

Database name.

Returned result

Parameter	Description
location	Database location.
comment	Database remarks. If there are no database remarks, the value is null.
database	Database name.
owner	Database owner.
owertype	Type of the database owner.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/ddl/database/default'

ddl/database/:db (PUT)

Description
Creates a database.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db

Parameter

Parameter	Description
:db	Database name.
group	User group used for creating the database.
permission	Permission used for creating the database.
location	Database location.
comment	Database remarks, for example, description.
properties	Database properties.

Returned result

Parameter	Description
database	Name of the newly created database.

Example

curl -i -u : --insecure --negotiate -X PUT -HContent-type:application/json -d '{"location": "/tmp/a", "comment": "my db", "properties": {"a": "b"}}' 'https://10.64.35.144:9111/templeton/v1/ddl/database/db2'

ddl/database/:db (DELETE)

Description
Deletes a database.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db

Parameter

Parameter	Description
:db	Database name.
ifExists	If the specified database does not exist, Hive returns an error unless ifExists is set to true.
option	Set the parameter to cascade or restrict. If you set it to cascade, all data and definitions are cleared. If you set it to restrict, the table content is empty and the mode does not exist.

Returned result

Parameter	Description
database	Name of the deleted database.

Example

curl -i -u : --insecure --negotiate -X DELETE 'https://10.64.35.144:9111/templeton/v1/ddl/database/db3?ifExists=true'

ddl/database/:db/table (GET)

Description
Lists all tables in the database.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table

Parameter

Parameter	Description
:db	Database name.
like	Regular expression used to match a table name.

Returned result

Parameter	Description
database	Database name.
tables	List of tables in the database.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/ddl/database/default/table'

ddl/database/:db/table/:table (GET)

Description
Obtains details about a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
format	The format is "format=extended". If you want to see additional information, use "table extended like".

Returned result

Parameter	Description
columns	Column name and type.
database	Database name.
table	Table name.
partitioned	Whether a table is a partition table. This parameter is available only when the table format is extended.
location	Table location. This parameter is available only when the table format is extended.
outputformat	Output format. This parameter is available only when the table format is extended.
inputformat	Input format. This parameter is available only when the table format is extended.
owner	Table owner. This parameter is available only when the table format is extended.
partitionColumns	Partition column. This parameter is available only when the table format is extended.

Example

curl -i -u : --insecure --negotiate 'https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1?format=extended'

ddl/database/:db/table/:table (PUT)

Description
Creates a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table

Parameter

Parameter	Description
:db	Database name.
:table	New table name.
group	User group used for creating the table.
permissions	Permission used for creating the table.
external	Allows you to specify a location so that Hive does not use the default location for this table.
ifNotExists	If this parameter is set to true, no error is reported if a table exists.
comment	Remarks.
columns	Column description, including the column name, type, and optional remarks.
partitionedBy	Partition column description, which is used to partition tables. The columns parameter is used to list the column name, type, and optional remarks.
clusteredBy	Bucket column description, including the columnNames, sortedBy, and numberOfBuckets parameters. The columnNames parameter includes columnName and sorting sequence (ASC indicates an ascending order, and DESC indicates a descending order).
format	Storage format. The parameters include rowFormat, storedAs, and storedBy.
location	HDFS path.
tableProperties	Table property names and values (name-value pairs).

Returned result

Parameter	Description
database	Database name.
table	Table name.

Example

curl -i -u : --insecure --negotiate -X PUT -HContent-type:application/json -d '{"columns": [{"name": "id", "type": "int"}, {"name": "name","type": "string"}], "comment": "hello","format": {"storedAs": "orc"} }' 'https://10.64.35.144:9111/templeton/v1/ddl/database/db3/table/tbl1'

ddl/database/:db/table/:table (POST)

Description
Renames a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table

Parameter

Parameter	Description
:db	Database name.
:table	Existing table name.
rename	New table name.

Returned result

Parameter	Description
database	Database name.
table	New table name.

Example

curl -i -u : --insecure --negotiate -d rename=table1 'https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/tbl1'

ddl/database/:db/table/:table (DELETE)

Description
Deletes a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
ifExists	If this parameter is set to true, no error is reported.

Returned result

Parameter	Description
database	Database name.
table	Table name.

Example

curl -i -u : --insecure --negotiate -X DELETE 'https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/table2?ifExists=true'

ddl/database/:db/table/:existingtable/like/:newtable (PUT)

Description
Creates a table that is the same as an existing table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:existingtable/like/:newtable

Parameter

Parameter	Description
:db	Database name.
:existingtable	Existing table name.
:newtable	New table name.
group	User group used for creating the table.
permissions	Permission used for creating the table.
external	Allows you to specify a location so that Hive does not use the default location for this table.
ifNotExists	If this parameter is set to true, the Hive does not report an error if a table already exists.
location	HDFS path.

Returned result

Parameter	Description
database	Database name.
table	Table name.

Example

curl -i -u : --insecure --negotiate -X PUT -HContent-type:application/json -d '{"ifNotExists": "true"}' 'https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/like/tt1'

ddl/database/:db/table/:table/partition(GET)

Description
Lists information about all partitions of a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/partition

Parameter

Parameter	Description
:db	Database name.
:table	Table name.

Returned result

Parameter	Description
database	Database name.
table	Table name.
partitions	List of partition attribute values and partition names.

Example

curl -i -u : --insecure --negotiate https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/x1/partition

ddl/database/:db/table/:table/partition/:partition(GET)

Description
Lists information about a specific partition of a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/partition/:partition

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
:partition	Partition name. Exercise caution when decoding HTTP quote, for example, country=%27algeria%27.

Returned result

Parameter	Description
database	Database name.
table	Table name.
partition	Partition name.
partitioned	If this parameter is set to true, the table is a partitioned table.
location	Storage path of the table.
outputFormat	Output format.
columns	Column name, type, and remarks.
owner	Owner.
partitionColumns	Partition column.
inputFormat	Input format.
totalNumberFiles	Number of files in a partition.
totalFileSize	Total size of files in a partition.
maxFileSize	Maximum file size.
minFileSize	Minimum file size.
lastAccessTime	Last access time.
lastUpdateTime	Last update time.

Example

curl -i -u : --insecure --negotiate https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/x1/partition/dt=1

ddl/database/:db/table/:table/partition/:partition(PUT)

Description
Adds a table partition.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/partition/:partition

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
group	User group used for creating a partition.
permissions	User permission used for creating a partition.
location	Storage location of the new partition.
ifNotExists	If this parameter is set to true, the system reports an error when the partition already exists.

Returned result

Parameter	Description
database	Database name.
table	Table name.
partitions	Partition name.

Example

curl -i -u : --insecure --negotiate -X PUT -HContent-type:application/json -d '{}' https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/x1/partition/dt=10

ddl/database/:db/table/:table/partition/:partition(DELETE)

Description
Deletes a table partition.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/partition/:partition

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
group	User group used for deleting a new partition.
permissions	User permission used for deleting a new partition. The format is rwxrw-r-x.
ifExists	If the specified partition does not exist, the Hive reports an error, unless this parameter is set to true.

Returned result

Parameter	Description
database	Database name.
table	Table name.
partitions	Partition name.

Example

curl -i -u : --insecure --negotiate -X DELETE -HContent-type:application/json -d '{}' https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/x1/partition/dt=10

ddl/database/:db/table/:table/column(GET)

Description
Obtains a column list of a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/column

Parameter

Parameter	Description
:db	Database name.
:table	Table name.

Returned result

Parameter	Description
database	Database name.
table	Table name.
columns	Column name and type.

Example

curl -i -u : --insecure --negotiate https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/column

ddl/database/:db/table/:table/column/:column(GET)

Description
Obtains details about a column in a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/column/:column

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
:column	Column name.

Returned result

Parameter	Description
database	Database name.
table	Table name.
column	Column name and type.

Example

curl -i -u : --insecure --negotiate https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/column/id

ddl/database/:db/table/:table/column/:column(PUT)

Description
Adds a column to a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/column/:column

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
:column	Column name.
type	Column type, for example, string and int.
comment	Column remarks, for example, description.

Returned result

Parameter	Description
database	Database name.
table	Table name.
column	Column name.

Example

curl -i -u : --insecure --negotiate -X PUT -HContent-type:application/json -d '{"type": "string", "comment": "new column"}'  https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/column/name

ddl/database/:db/table/:table/property(GET)

Description
Obtains properties of a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/property

Parameter

Parameter	Description
:db	Database name.
:table	Table name.

Returned result

Parameter	Description
database	Database name.
table	Table name.
properties	Property.

Example

curl -i -u : --insecure --negotiate https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/property

ddl/database/:db/table/:table/property/:property(GET)

Description
Obtains a specific property value of a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/property/:property

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
:property	Property name.

Returned result

Parameter	Description
database	Database name.
table	Table name.
property	Property list.

Example

curl -i -u : --insecure --negotiate https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/property/last_modified_by

ddl/database/:db/table/:table/property/:property(PUT)

Description
Adds a property value to a table.
URL
https://www.myserver.com/templeton/v1/ddl/database/:db/table/:table/property/:property

Parameter

Parameter	Description
:db	Database name.
:table	Table name.
:property	Property name.
value	Property value.

Returned result

Parameter	Description
database	Database name.
table	Table name.
property	Property name.

Example

curl -i -u : --insecure --negotiate -X PUT -HContent-type:application/json -d '{"value": "my value"}' https://10.64.35.144:9111/templeton/v1/ddl/database/default/table/t1/property/mykey

mapreduce/jar(POST)

Description
Executes a MapReduce job. Before executing a MapReduce job, upload the JAR file of the MapReduce job to HDFS.
URL
https://www.myserver.com/templeton/v1/mapreduce/jar

Parameter

Parameter	Description
jar	JAR file of the MapReduce job to be executed.
class	Class of the MapReduce job to be executed.
libjars	JAR file names of classpath to be added, separated by commas (,).
files	Names of files to be copied to the MapReduce cluster, separated by commas (,).
arg	Input parameter received by the Main class.
define	This parameter is used to configure Hadoop in the define=NAME=VALUE format.
statusdir	WebHCat writes the status of the MapReduce task to statusdir. If this parameter is set, you need to manually delete it.
enablelog	If statusdir is set and enablelog is set to true, Hadoop task configurations and logs are collected to $statusdir/logs. Then, successful and failed attempts are recorded in the logs. The layout of the subdirectories in $statusdir/logs is as follows: logs/$job_id (directory for $job_id) logs/$job_id/job.xml.html logs/$job_id/$attempt_id (directory for $attempt_id) logs/$job_id/$attempt_id/stderr logs/$job_id/$attempt_id/stdout logs/$job_id/$attempt_id/syslog Only Hadoop 1.X is supported.
callback	Callback address after MapReduce job execution. Use $jobId to embed the job ID in the callback address. In the callback address, replace the $jobId with the job ID.

Returned result

Parameter	Description
id	Job ID, similar to job_201110132141_0001.

Example

curl -i -u : --insecure --negotiate -d jar="/tmp/word.count-0.0.1-SNAPSHOT.jar" -d class=com.huawei.word.count.WD -d statusdir="/output" -d enablelog=true "https://10.64.35.144:9111/templeton/v1/mapreduce/jar"

mapreduce/streaming(POST)

Description
Submits a MapReduce job in Streaming mode.
URL
https://www.myserver.com/templeton/v1/mapreduce/streaming

Parameter

Parameter	Description
input	Input path of Hadoop.
output	Output save path. If this parameter is not specified, WebHCat will store the output in a path that can be found by using queue resources.
mapper	Location of the mapper program.
reducer	Location of the reducer program.
files	Add HDFS files to the distributed cache.
arg	Set an argument.
define	Set Hadoop configuration variables in the define=NAME=VALUE format.
cmdenv	Set environment variables in the cmdenv=NAME=VALUE format.
statusdir	WebHCat writes the status of the MapReduce task to statusdir. If this parameter is set, you need to manually delete it.
enablelog	If statusdir is set and enablelog is set to true, Hadoop task configurations and logs are collected to $statusdir/logs. Then, successful and failed attempts are recorded in the logs. The layout of the subdirectories in $statusdir/logs is as follows: logs/$job_id (directory for $job_id) logs/$job_id/job.xml.html logs/$job_id/$attempt_id (directory for $attempt_id) logs/$job_id/$attempt_id/stderr logs/$job_id/$attempt_id/stdout logs/$job_id/$attempt_id/syslog Only Hadoop 1.X is supported.
callback	Callback address after MapReduce job execution. Use $jobId to embed the job ID in the callback address. In the callback address, replace the $jobId with the job ID.

Returned result

Parameter	Description
id	Job ID, similar to job_201110132141_0001.

Example

curl -i -u : --insecure --negotiate -d input=/input -d output=/oooo -d mapper=/bin/cat -d reducer="/usr/bin/wc -w" -d statusdir="/output" 'https://10.64.35.144:9111/templeton/v1/mapreduce/streaming'

NOTE:

Before using this API, ensure that the prerequisites are met. For details, see the Hive rule in the Development Specifications.

/hive(POST)

Description
Runs Hive commands.
URL
https://www.myserver.com/templeton/v1/hive

Parameter

Parameter	Description
execute	Hive commands, including entire and short Hive commands.
file	HDFS file containing Hive commands.
files	Names of files to be copied to the MapReduce cluster, separated by commas (,).
arg	Set an argument.
define	Hive configuration. The format is define=key=value. When using the post statement, you need to configure the scratch dir of the instance. The WebHCat instance uses define=hive.exec.scratchdir=/tmp/hive-scratch, and the WebHCat1 instance uses define=hive.exec.scratchdir=/tmp/hive1-scratch. The same rule applies to other instances.
statusdir	WebHCat writes the status of the MapReduce task to statusdir. If this parameter is set, you need to manually delete it.
enablelog	If statusdir is set and enablelog is set to true, Hadoop task configurations and logs are collected to $statusdir/logs. Then, successful and failed attempts are recorded in the logs. The layout of the subdirectories in $statusdir/logs is as follows: logs/$job_id (directory for $job_id) logs/$job_id/job.xml.html logs/$job_id/$attempt_id (directory for $attempt_id) logs/$job_id/$attempt_id/stderr logs/$job_id/$attempt_id/stdout logs/$job_id/$attempt_id/syslog
callback	Callback address after MapReduce job execution. Use $jobId to embed the job ID in the callback address. In the callback address, replace the $jobId with the job ID.

Returned result

Parameter	Description
id	Job ID, similar to job_201110132141_0001.

Example

curl -i -u : --insecure --negotiate -d execute="select count(*) from t1" -d define=hive.exec.scratchdir=/tmp/hive-scratch -d statusdir="/output" "https://10.64.35.144:9111/templeton/v1/hive"

jobs(GET)

Description
Obtains all job IDs.
URL
https://www.myserver.com/templeton/v1/jobs

Parameter

Parameter	Description
fields	If this parameter is set to , details about each job are returned. If this parameter is not set, only a job ID is returned. The parameter can only be set to . If the parameter is set to another value, an exception occurs.
jobid	If jobid is set, only jobs whose lexicographic order is greater than jobid are returned. For example, if the value of jobid is job_201312091733_0001, only the job whose value is greater than the value can be returned. The number of returned jobs depends on the value of numrecords.
numrecords	If numrecords and jobid are set, the jobid list is sorted lexicographically. After jobid is returned, the maximum value of numrecords can be obtained. If jobid is not set but numrecords is set, the maximum value of numrecords can be obtained after the jobid list is sorted lexicographically. In contrast, if numrecords is not set but jobid is set, all jobs whose lexicographic orders are greater than jobid will be returned.
showall	If showall is set to true, the request will return all jobs the user has permission to view, not only the jobs belonging to the user.

Returned result

Parameter	Description
id	Job id
detail	If the value of showall is true, details are displayed. Otherwise, the value is null.

Example

curl -i -u : --insecure --negotiate  "https://10.64.35.144:9111/templeton/v1/jobs"

jobs/:jobid(GET)

Description
Obtains information about a specified job.
URL
https://www.myserver.com/templeton/v1/jobs/:jobid

Parameter

Parameter	Description
jobid	Job ID, received after a job is created.

Returned result

Parameter	Description
status	JSON object containing job status information.
profile	JSON object containing job information. WebHCat parses information in the JobProfile object. The object varies according to the Hadoop version.
id	Job ID.
percentComplete	Job completion percentage, for example, 75%. If the job is complete, the value is null.
user	User who created the job.
callback	Callback URL (if any).
userargs	Parameter argument and parameter value when a user submits a job.
exitValue	Exit value of the job.

Example

curl -i -u : --insecure --negotiate  "https://10.64.35.144:9111/templeton/v1/jobs/job_1440386556001_0255"

jobs/:jobid(DELETE)

Description
Kills a job.
URL
https://www.myserver.com/templeton/v1/jobs/:jobid

Parameter

Parameter	Description
:jobid	ID of the job to be deleted.

Returned result

Parameter	Description
user	User who submits a job.
status	JSON object containing job status information.
profile	JSON object containing job information. WebHCat parses information in the JobProfile object. The object varies according to the Hadoop version.
id	Job ID.
callback	Callback URL (if any).

Example

curl -i -u : --insecure --negotiate -X DELETE  "https://10.64.35.143:9111/templeton/v1/jobs/job_1440386556001_0265"

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