thingsboard: Error during building from source

I am trying to build thingsboard using the source code by following the guide at the following link

I have the following configuration

• Ubuntu 16.04 LTS

• java version “1.8.0_151”

• Apache Maven 3.3.9

Firstly, when I try to clone the code using the git clone git@github.com:thingsboard/thingsboard.git command, I got the following error.

Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

I managed to clone the code using the web URL. However, when I try to build the code using the command mvn clean install, I get an error while running the DAO tests.

2017-12-15 09:15:15,916 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Changing key of admin settings entry is prohibited!]
2017-12-15 09:15:15,922 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Key should be specified!]
2017-12-15 09:15:15,942 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Provided json structure is different from stored one '{"mailFrom":"Thingsboard <sysadmin@localhost.localdomain>","smtpProtocol":"smtp","smtpHost":"localhost","smtpPort":"25","timeout":"10000","enableTls":"false","username":"","password":"","newKey":"my new value"}'!]
2017-12-15 09:15:35,371 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Asset should be assigned to tenant!]
2017-12-15 09:15:40,408 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Can't assign asset to non-existent customer!]
2017-12-15 09:15:40,452 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Asset is referencing to non-existent tenant!]
2017-12-15 09:15:40,491 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Can't assign asset to customer from different tenant!]
2017-12-15 09:15:46,733 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Asset name should be specified!]
2017-12-15 09:15:57,672 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Customer should be assigned to tenant!]
2017-12-15 09:16:02,345 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Invalid email address format 'invalid@mail'!]
2017-12-15 09:16:02,492 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Customer is referencing to non-existent tenant!]
2017-12-15 09:16:02,522 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Customer title should be specified!]
2017-12-15 09:16:40,803 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Can't assign dashboard to non-existent customer!]
2017-12-15 09:16:40,908 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Dashboard should be assigned to tenant!]
2017-12-15 09:16:40,945 [main] ERROR o.t.server.dao.service.DataValidator - Data object is invalid: [Can't assign dashboard to customer from different tenant!]

The final build results are as follows.

Results :

Tests run: 0, Failures: 0, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] Thingsboard ........................................ SUCCESS [  2.820 s]
[INFO] Thingsboard Server Commons ......................... SUCCESS [  0.098 s]
[INFO] Thingsboard Server Common Data ..................... SUCCESS [  8.976 s]
[INFO] Thingsboard Server Common Messages ................. SUCCESS [  1.375 s]
[INFO] Thingsboard Server Common Transport components ..... SUCCESS [  0.717 s]
[INFO] Thingsboard Server DAO Layer ....................... FAILURE [03:13 min]
[INFO] Thingsboard Server Extensions API .................. SKIPPED
[INFO] Thingsboard Server Core Extensions ................. SKIPPED
[INFO] Thingsboard Extensions ............................. SKIPPED
[INFO] Thingsboard Server RabbitMQ Extension .............. SKIPPED
[INFO] Thingsboard Server REST API Call Extension ......... SKIPPED
[INFO] Thingsboard Server Kafka Extension ................. SKIPPED
[INFO] Thingsboard Server MQTT Extension .................. SKIPPED
[INFO] Thingsboard Server SQS Extension ................... SKIPPED
[INFO] Thingsboard Server SNS Extension ................... SKIPPED
[INFO] Thingsboard Server Transport Modules ............... SKIPPED
[INFO] Thingsboard HTTP Transport ......................... SKIPPED
[INFO] Thingsboard COAP Transport ......................... SKIPPED
[INFO] Thingsboard MQTT Transport ......................... SKIPPED
[INFO] Thingsboard Server UI .............................. SKIPPED
[INFO] Thingsboard Server Tools ........................... SKIPPED
[INFO] ThingsBoard Server Application ..................... SKIPPED

So, I tried to build the code without running the tests using the command mvn clean install -DskipTests. The previous error was avoided, however, I get the following error.

[WARNING] npm WARN deprecated coffee-script@1.12.7: CoffeeScript on NPM has moved to "coffeescript" (no hyphen)
[WARNING] npm WARN deprecated babel-preset-es2015@6.24.1: 🙌  Thanks for using Babel: we recommend using babel-preset-env now: please read babeljs.io/env to update!
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] Thingsboard ........................................ SUCCESS [  2.674 s]
[INFO] Thingsboard Server Commons ......................... SUCCESS [  0.100 s]
[INFO] Thingsboard Server Common Data ..................... SUCCESS [  7.677 s]
[INFO] Thingsboard Server Common Messages ................. SUCCESS [  1.396 s]
[INFO] Thingsboard Server Common Transport components ..... SUCCESS [  0.760 s]
[INFO] Thingsboard Server DAO Layer ....................... SUCCESS [ 12.868 s]
[INFO] Thingsboard Server Extensions API .................. SUCCESS [  1.748 s]
[INFO] Thingsboard Server Core Extensions ................. SUCCESS [  6.365 s]
[INFO] Thingsboard Extensions ............................. SUCCESS [  0.057 s]
[INFO] Thingsboard Server RabbitMQ Extension .............. SUCCESS [  3.647 s]
[INFO] Thingsboard Server REST API Call Extension ......... SUCCESS [  1.297 s]
[INFO] Thingsboard Server Kafka Extension ................. SUCCESS [  3.828 s]
[INFO] Thingsboard Server MQTT Extension .................. SUCCESS [  0.992 s]
[INFO] Thingsboard Server SQS Extension ................... SUCCESS [  4.700 s]
[INFO] Thingsboard Server SNS Extension ................... SUCCESS [  2.576 s]
[INFO] Thingsboard Server Transport Modules ............... SUCCESS [  0.257 s]
[INFO] Thingsboard HTTP Transport ......................... SUCCESS [  0.834 s]
[INFO] Thingsboard COAP Transport ......................... SUCCESS [  1.426 s]
[INFO] Thingsboard MQTT Transport ......................... SUCCESS [  1.354 s]
[INFO] Thingsboard Server UI .............................. FAILURE [04:15 min]
[INFO] Thingsboard Server Tools ........................... SKIPPED
[INFO] ThingsBoard Server Application ..................... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 05:11 min
[INFO] Finished at: 2017-12-15T09:24:37+00:00
[INFO] Final Memory: 74M/239M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.github.eirslett:frontend-maven-plugin:1.0:npm (npm install) on project ui: Failed to run task: 'npm install' failed. (error code 137) -> [Help 1]

Can somebody please help?

Thanks