Failed connection when trying for Heroku PostgreSQL with Spring - postgresql

Question

I am trying to set up a Spring Boot application. Currently I am working in a local environment and I have a Heroku PostgreSQL db. When I start my application it starts with error:
HikariPool-1 - Exception during pool initialization.
org.postgresql.util.PSQLException: El intento de conexión falló.
...
Caused by: java.net.UnknownHostException: #host
...
HHH000342: Could not obtain connection to query metadata
Where I have added the correct hostname and hideen it for security. I know this hostname is right since I've managed to connect using an Express app.
My POM.xml has the following dependencies:}
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
And my application.properties file is:
spring.datasource.url=jdbc:postgresql://#host:5432/dal2fiqv9or5eg?user=----&password=----&sslmode=require
spring.datasource.username=----
spring.datasource.password=----
spring.datasource.driver-class-name=org.postgresql.Driver
spring.jpa-hibernate.ddl-auto=create-drop
spring.jpa.show=true
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect
spring.jpa.properties.hibernate.format_sql=true
Whre once again I hid the host, username and pwd.
After this the application starts.

Answer 1

The spring.datasource.url property in your application.properties seems to be incorrect.
This file has worked for me:
#postgres parameters
spring.datasource.url=jdbc:postgresql://<host>:<port>/<database>
spring.datasource.username=<user>
spring.datasource.password=<password>
spring.jpa.show-sql=true
## Hibernate Properties
# The SQL dialect makes Hibernate generate better SQL for the chosen database
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect
# Hibernate ddl auto (create, create-drop, validate, update)
spring.jpa.hibernate.ddl-auto = update
logging.level.org.springframework=TRACE
logging.level.org.hibernate.type=TRACE
server.port=${PORT:8080}
The values for port, host, database, user, and password can be derived from the HerokuPostgres addon you add to your Heroku app
Do not add # or any special symobols. Simply replace the values with the values you see in Heroku.
eg: spring.datasource.url=jdbc:postgresql://myhostname:5432/mydbname