Download RPM and Dependencies without actual installation

[root@localhost ~]# yum install --downloadonly --downloaddir /root/postgresql postgresql10 postgresql10-server
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  * base: mirror.qoxy.com
  * extras: centos.ipserverone.com
  * updates: centos.ipserverone.com
Resolving Dependencies
--> Running transaction check
---> Package postgresql10.x86_64 0:10.1-1PGDG.rhel7 will be installed
--> Processing Dependency: postgresql10-libs(x86-64) = 10.1-1PGDG.rhel7 for package: postgresql10-10.1-1PGDG.rhel7.x86_64
--> Processing Dependency: libicu for package: postgresql10-10.1-1PGDG.rhel7.x86_64
--> Processing Dependency: libpq.so.5()(64bit) for package: postgresql10-10.1-1PGDG.rhel7.x86_64
---> Package postgresql10-server.x86_64 0:10.1-1PGDG.rhel7 will be installed
--> Running transaction check
---> Package libicu.x86_64 0:50.1.2-15.el7 will be installed
---> Package postgresql10-libs.x86_64 0:10.1-1PGDG.rhel7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================
  Package                         Arch               Version                      Repository                          Size
================================================================================
Installing:
  postgresql10                    x86_64             10.1-1PGDG.rhel7             pgdg10-updates-testing             1.5 M
  postgresql10-server             x86_64             10.1-1PGDG.rhel7             pgdg10-updates-testing             4.3 M
Installing for dependencies:
  libicu                          x86_64             50.1.2-15.el7                base                               6.9 M
  postgresql10-libs               x86_64             10.1-1PGDG.rhel7             pgdg10-updates-testing             347 k

Transaction Summary
====================================================================================
Install  2 Packages (+2 Dependent packages)

Total download size: 13 M
Installed size: 49 M
Background downloading packages, then exiting:
(1/4): libicu-50.1.2-15.el7.x86_64.rpm                                                             | 6.9 MB  00:00:00
(2/4): postgresql10-libs-10.1-1PGDG.rhel7.x86_64.rpm                                               | 347 kB  00:00:03
(3/4): postgresql10-10.1-1PGDG.rhel7.x86_64.rpm                                                    | 1.5 MB  00:00:05
(4/4): postgresql10-server-10.1-1PGDG.rhel7.x86_64.rpm                                             | 4.3 MB  00:00:06
--------------------------------------------------------------------------------------------------------------------------
Total                                                                                     1.3 MB/s |  13 MB  00:00:10
exiting because "Download Only" specified