Repository navigation
Breaking Change: Default console logger format set to JSON #3274
Description
Breaking Change: Default console logger format set to JSON
In the .NET 6 aspnet image type, the default console logger format has been changed to a JSON formatter. The default in .NET 5 was set to the simple console formatter. This change was made in order to have a default configuration that works with automated tools that rely on a machine-readable format like JSON.
Details
This change only impacts the aspnet image type. The runtime and sdk image types are unaffected and remain configured with the simple console formatter.
Any code which logs to the console will have its output affected by this change. As an example, the following output illustrates the differences in the default output when starting an ASP.NET Core container:
.NET 5 Output (simple format)
warn: Microsoft.AspNetCore.DataProtection.Repositories.FileSystemXmlRepository[60]
Storing keys in a directory '/root/.aspnet/DataProtection-Keys' that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed.
warn: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[35]
No XML encryptor configured. Key {94519747-9185-49e1-b5af-352c1a5078da} may be persisted to storage in unencrypted form.
info: Microsoft.Hosting.Lifetime[14]
Now listening on: http://[::]:80
info: Microsoft.Hosting.Lifetime[0]
Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
Content root path: /app
.NET 6 Output (JSON format)
{"EventId":60,"LogLevel":"Warning","Category":"Microsoft.AspNetCore.DataProtection.Repositories.FileSystemXmlRepository","Message":"Storing keys in a directory \u0027/root/.aspnet/DataProtection-Keys\u0027 that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed.","State":{"Message":"Storing keys in a directory \u0027/root/.aspnet/DataProtection-Keys\u0027 that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed.","path":"/root/.aspnet/DataProtection-Keys","{OriginalFormat}":"Storing keys in a directory \u0027{path}\u0027 that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed."}}
{"EventId":35,"LogLevel":"Warning","Category":"Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager","Message":"No XML encryptor configured. Key {86cafacf-ab57-434a-b09c-66a929ae4fd7} may be persisted to storage in unencrypted form.","State":{"Message":"No XML encryptor configured. Key {86cafacf-ab57-434a-b09c-66a929ae4fd7} may be persisted to storage in unencrypted form.","KeyId":"86cafacf-ab57-434a-b09c-66a929ae4fd7","{OriginalFormat}":"No XML encryptor configured. Key {KeyId:B} may be persisted to storage in unencrypted form."}}
{"EventId":14,"LogLevel":"Information","Category":"Microsoft.Hosting.Lifetime","Message":"Now listening on: http://[::]:80","State":{"Message":"Now listening on: http://[::]:80","address":"http://[::]:80","{OriginalFormat}":"Now listening on: {address}"}}
{"EventId":0,"LogLevel":"Information","Category":"Microsoft.Hosting.Lifetime","Message":"Application started. Press Ctrl\u002BC to shut down.","State":{"Message":"Application started. Press Ctrl\u002BC to shut down.","{OriginalFormat}":"Application started. Press Ctrl\u002BC to shut down."}}
{"EventId":0,"LogLevel":"Information","Category":"Microsoft.Hosting.Lifetime","Message":"Hosting environment: Production","State":{"Message":"Hosting environment: Production","envName":"Production","{OriginalFormat}":"Hosting environment: {envName}"}}
{"EventId":0,"LogLevel":"Information","Category":"Microsoft.Hosting.Lifetime","Message":"Content root path: /app","State":{"Message":"Content root path: /app","contentRoot":"/app","{OriginalFormat}":"Content root path: {contentRoot}"}}
Overriding the Default Configuration
The logger format type can be changed by setting or unsetting the Logging__Console__FormatterName environment variable or via code change (see Console log formatting for more details).
Example:
$ docker run --rm -it -p 8000:80 -e Logging__Console__FormatterName="" mcr.microsoft.com/dotnet/samples:aspnetapp
warn: Microsoft.AspNetCore.DataProtection.Repositories.FileSystemXmlRepository[60]
Storing keys in a directory '/root/.aspnet/DataProtection-Keys' that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed.
warn: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[35]
No XML encryptor configured. Key {8d4ddd1d-ccfc-4898-9fe1-3e7403bf23a0} may be persisted to storage in unencrypted form.
info: Microsoft.Hosting.Lifetime[14]
Now listening on: http://[::]:80
info: Microsoft.Hosting.Lifetime[0]
Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
Content root path: /app
Activity
ralftar commentedon Nov 17, 2021
Is it by design or that configuring
FormatterNametosimpleinappsettings.jsonis not applied when running inside a docker container?As opposite to native Windows where the simple formatting is applied and overrides the default JSON format.(edit: simple is ofc. the default in windows.. but the precedence question still stands).mthalman commentedon Nov 17, 2021
@shirhatti - What takes precedence here? The
appsettings.jsonconfiguration or the setting of theLogging__Console__FormatterNameenvironment variable?kodedylf commentedon Nov 25, 2021
As I understand it, the environment variable takes precedence, so by setting the environment variable in the aspnet Docker images, it's no longer possible to configure console logging via appsettings.json.
ralftar commentedon Nov 25, 2021
I have a hunch that
FormatterNameinsideappsettings.jsonwon't take effect even if theLogging__Console__FormatterNameenvironment variable is not set.(I ended up setting the environment variable inside the Dockerfile)
davidfowl commentedon Nov 28, 2021
cc @shirhatti
wuhkuh commentedon Nov 29, 2021
@ralftar That's because
FormattingNamecontains a typo 😉The environment variable
Logging__Console__FormatterNamewith valuesimpleis the equivalent of{ "Logging": { "Console": { "FormatterName": "simple" } } }We've unset
Logging__Console__FormatterNamein our dockerfile (based on the aspnet image) like so:ENV Logging__Console__FormatterName=And now everything works as expected.
ralftar commentedon Nov 29, 2021
Thanks for pointing this out @wuhkuh, but a comment typo was also all that it was.
The original question still stands: If
Logging__Console__FormatterNameevt variable is not set thenFormatterNameinside appsettings.json won't take effect, is this by intention?Same applies to @wuhkuh's example above: Setting
FormatterNametojsonin appsettings.json won't take effect, even whenLogging__Console__FormatterNameis "unset". Thus appsettings'sFormatterNamewill also here not be applied as expected.Regarding setting
Logging__Console__FormatterNameto blank: I suspects it's really not an "unset", but rather sets to simple formatter when `Logging__Console__FormatterName is blank...?wuhkuh commentedon Nov 30, 2021
Ah, good catch, you're spot on: it uses the simple formatter because the environment variable now contains an empty string.
To work around this, you can supply an entrypoint script, calling
unset Logging__Console__FormatterNamebefore invoking your application.Docker does not support removing environment variables from a previous layer; it would require removal of that layer 😞
ralftar commentedon Nov 30, 2021
Since we are diving into this 🐰🕳️ another observation for the record:
Setting
Logging__Console__FormatterNameto blank is not the same as setting it tosimple. When set to blank there are no level colors in the console, and more importantly:FormatterOptionswithTimestampFormatinside appsettings.json for the console is not applied.MaxRev-Dev commentedon Dec 6, 2021
Love this. I'm not using azure containers, rather bare metal droplets. After updating from .net5.0 to .net6.0, I figured out that the logger somehow changed it's configuration. So I've opened the docs and did not found any note or warning about this breaking change in there. Only 5 minutes of "googling" revealed me this issue.
https://docs.microsoft.com/en-us/dotnet/core/extensions/console-log-formatter
Change logging for docker back to simple format