Liquibase fails if computer is not connected to internet

问题

When I am trying to start Liquibase (Karaf is used), I get the following error

'Failed to read schema document http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xml, bacause 1) could not find the document; 2) the document could not be read; 3) the root element of the document is not '

If computer is connected to internet, this error is not reproduced.

回答1:

I stumbled across this myself recently.

You need to change this:

<databaseChangeLog
    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd">

and remove the URL to the XSD:

<databaseChangeLog
    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog dbchangelog-3.0.xsd">

Note the space between http://www.liquibase.org/xml/ns/dbchangelog and dbchangelog-3.0.xsd. The first element is the URI for the namespace, the second element points to the actual XSD file. If that doesn't include a URL, the XML parser will try to use a local file.

Then put the actual XSD into the same directory where the changelog XML is located.

You need to download that from a computer with internet access of course, e.g. using:

wget http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd

or by simply opening the URL with the browser and then saving the file.

Note that you also need to specify a .xsd file for the schema location, not a .xml (as it is shown in the question).

回答2:

This problem was fixed. It turns Liquibase-osgi.jar contains own packages and also it contains liquibase.jar. When LiquibaseEntityResolver.java tries to find *.xsd, it finds two files *.xsd with same name. And after that liquibase throws Exception. I deleted duplicate files and everything was working

BTW Root element of changelog file looks like

<databaseChangeLog
    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd">

回答3:

Thk for your awswer.

But, liquibase has own xsd file in liquibase/parser/core/xml/.

If we run liquibase, for example, in tomcat, it works correctly http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd" will be replaced to liquibase/parser/core/xml/dbchangelog-3.0.xsd by LiquibaseEntityResolver.java

回答4:

For those using Maven and the liquibase-maven-plugin plugin, be sure to add all liquibase dependencies into the plugin dependencies themselves.

e.g.

    <plugin>
      ...
      <artifactId>liquibase-maven-plugin</artifactId>
      ...
      <dependencies>
        <dependency>
           ...
           <artifactId>liquibase-core</artifactId>
        </dependency>
      </dependencies>
    </plugin>

I had a similar issue where liquibase commands would not work while disconnected, because the plugin could not resolve the local schema .xsd file.

来源：https://stackoverflow.com/questions/32350054/liquibase-fails-if-computer-is-not-connected-to-internet

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liquibase