nuget 'packages' element is not declared warning

144

votes

not a showstopper but when using nuget in a project, it creates a packages.config file with this shape

<?xml version="1.0" encoding="utf-8"?>
<packages>
   ... your packages
</packages>

this gives a warning in VS

The 'packages' element is not declared.

The origin of the problem got something to do with the xml declaration I guess.

Also I think that the default definition package shouldn't throw warnings.

Does anyone know what should I change it to so I don't get this warning? (ie even if I can see it only when the file is open, it also shows as a warning constantly with certain CA rules on.)

xmlvisual-studionuget

I found [this solution][1] for this topic, which I think is better. [1]: stackoverflow.com/questions/2833243/… – Mario Lopez

tbh the real solution is to add the official schema... pls see my answer below – Stefan Z Camilleri

Here is corresponding issue on github: github.com/NuGet/Home/issues/1836 – dimaaan

189

votes

You will see it only when the file is open. When you'll close the file in Visual Studio the warnings goes away

http://nuget.codeplex.com/discussions/261638

115

votes

Actually the correct answer to this is to just add the schema to your document, like so

<packages xmlns="http://schemas.microsoft.com/packaging/2010/07/nuspec.xsd">

...and you're done :)

If the XSD is not already cached and unavailable, you can add it as follows from the NuGet console

Install-Package NuGet.Manifest.Schema -Version 2.0.0

Once this is done, as noted in a comment below, you may want to move it from your current folder to the official schema folder that is found in

%VisualStudioPath%\Xml\Schemas

94

votes

You can always make simple xsd schema for 'packages.config' to get rid of this warning. To do this, create file named "packages.xsd":

<?xml version="1.0" encoding="utf-8" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified"
      targetNamespace="urn:packages" xmlns="urn:packages">
  <xs:element name="packages">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="package" maxOccurs="unbounded">
          <xs:complexType>
            <xs:attribute name="id" type="xs:string" use="required" />
            <xs:attribute name="version" type="xs:string" use="required" />
            <xs:attribute name="targetFramework" type="xs:string" use="optional" />
            <xs:attribute name="allowedVersions" type="xs:string" use="optional" />
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

Location of this file (two options)

In the same folder as 'packages.config' file,
If you want to share packages.xsd across multiple projects, move it to the Visual Studio Schemas folder (the path may slightly differ, it's D:\Program Files (x86)\Microsoft Visual Studio 10.0\Xml\Schemas for me).

Then, edit <packages> tag in packages.config file (add xmlns attribute):

<packages xmlns="urn:packages">

Now the warning should disappear (even if packages.config file is open in Visual Studio).

6

votes

None of the answers will solve your problem permanently. If you go to the path of adding XSD (From Xml menu, select "Create schema"), you will end up having problems with the package manager as it will clean up your packages.config file when you add a new package.

The best solution is just ignore by closing the file when you don't use it.

5

votes

The problem is, you need a xsd schema for packages.config.

This is how you can create a schema (I found it here):

Open your Config file -> XML -> Create Schema

This would create a packages.xsd for you, and opens it in Visual Studio:

In my case, packages.xsd was created under this path:

C:\Users\MyUserName\AppData\Local\Temp

Now I don't want to reference the packages.xsd from a Temp folder, but I want it to be added to my solution and added to source control, so other users can get it... so I copied packages.xsd and pasted it into my solution folder. Then I added the file to my solution:

1. Copy packages.xsd in the same folder as your solution

2. From VS, right click on solution -> Add -> Existing Item... and then add packages.xsd

So, now we have created packages.xsd and added it to the Solution. All we need to do is to tell the config file to use this schema.

Open the config file, then from the top menu select:

XML -> Schemas...

Add your packages.xsd, and select Use this schema (see below)

3

votes

This happens because VS doesn't know the schema of this file. Note that this file is more of an implementation detail, and not something you normally need to open directly. Instead, you can use the NuGet dialog to manage the packages installed in a project.

1

votes

This works and remains even after adding a new package:

Add the following !DOCTYPE above the <packages> element:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE packages [
  <!ELEMENT packages (package*)>
  <!ELEMENT package EMPTY>
  <!ATTLIST package
  id CDATA #REQUIRED
  version CDATA #REQUIRED
  targetFramework CDATA #REQUIRED
  developmentDependency CDATA #IMPLIED>
]>

0

votes

Sometimes happens when you have an old project version. To solve it follow these steps:

Right click on References and select packages.config toPackageReference..
Click OK
Wait meanwhile project packages is updating

nuget 'packages' element is not declared warning

8 Answers