Seq CLI Vs UI: Inconsistent Property Handling Analysis

Aug 11, 2025 by Henrik Larsen 55 views

Inconsistent Property Handling in Seq and Seq CLI: An In-Depth Analysis

Hey guys! Let's dive deep into a quirky issue I've stumbled upon while working with Seq and its CLI. It's one of those things that makes you go, "Hmm, that's interesting..." So, I wanted to share my findings, get your thoughts, and maybe figure out if this is a bug or just a design quirk.

The Curious Case of Duplicate Property Keys

So, here's the deal: I noticed that the Seq UI is pretty chill about accepting properties with the same key name. I even made a little screencast to show you exactly what I mean:

https://github.com/user-attachments/assets/170c4c4b-e5ef-43b8-94d6-044b386dc8f0

Go ahead, take a peek! You'll see that I can happily add multiple properties with the same key in the Seq UI without any complaints. It's all sunshine and rainbows there.

But hold on, the plot thickens! When I try to do the exact same thing using the Seq CLI, things take a turn. The CLI throws a fit and rejects my attempt to create properties with duplicate keys. It's like the CLI is the strict parent, and the UI is the cool, lenient one. Let's take a closer look at what happens when I try this with the CLI. To demonstrate this, I attempted to create an API key using the Seq CLI, assigning multiple properties with the same key. The command I used was:

$ seqcli apikey create \
  --server http://seq.sako-ks.svc.cluster.local:80 --apikey XrF0gxCwOacxfK6LxhHv --title zzz \
--property="a=1" --property="a=2" --property="a=3"

And guess what? The CLI wasn't having any of it! It threw back this error message:

The command failed: An item with the same key has already been added. Key: a

Ouch! It seems the CLI is a stickler for unique keys. This immediately raised a question: Why the inconsistency? Is this a bug? Is it intended behavior? Or am I missing something crucial in how Seq handles properties? The error message is clear enough – it doesn't like duplicate keys. But the fact that the UI allows it makes this a puzzle worth solving. The inconsistency between the UI and CLI behaviors prompted me to dig deeper. I started thinking about the implications of allowing duplicate keys in the first place. In a system designed for structured logging and event management, properties are key-value pairs that add context to log events. They provide a way to filter, search, and analyze log data effectively. If duplicate keys are allowed, it raises questions about which value should be considered the "correct" one. How does Seq handle this internally? Does it take the first value, the last value, or something else entirely? These questions are crucial in understanding the underlying design and potential impact on data integrity and analysis.

Digging Deeper: What's Going On?

This discrepancy between the UI and CLI got me scratching my head. Is it a bug? Is it intentional? Or is there a good reason for this behavior that I'm just not seeing? Let's break it down:

The UI's Perspective: The Seq UI seems to be okay with multiple properties sharing the same key. This could be a design choice to allow for flexibility, maybe in scenarios where you want to capture a series of values under the same key. But how does Seq handle these duplicate values internally? Does it take the first one? The last one? Does it merge them somehow? This is a crucial question because it directly impacts how you can query and filter your logs. If the UI simply overwrites previous values with the latest one, you might lose valuable information. On the other hand, if it stores multiple values, you need to know how to access them. This behavior also raises questions about how Seq's query language (SQL-like) handles duplicate keys when filtering or aggregating data.
The CLI's Stance: The Seq CLI, on the other hand, is very clear: it doesn't want any duplicate keys. This approach makes sense from a data integrity perspective. By enforcing unique keys, the CLI ensures that each property has a single, unambiguous value. This can prevent confusion and errors when analyzing logs. However, this strictness also limits flexibility. There might be legitimate use cases where you want to associate multiple values with the same key, and the CLI's restriction would prevent you from doing so. This raises a usability question: is the CLI's strictness too restrictive? Should there be an option to allow duplicate keys, perhaps with a warning or a different syntax? Or is the current behavior the right balance between data integrity and flexibility?

To really understand what's going on, we need to think about how Seq stores and processes properties internally. Is there a fundamental difference in how the UI and CLI interact with Seq's API? Does the Seq server itself have a preference for unique keys, or is the restriction imposed by the CLI client? To answer these questions, we might need to delve into Seq's documentation or even its source code. Understanding the internal mechanisms will help us determine whether this inconsistency is a bug, a design choice, or a misunderstanding on my part.

Version Details

For context, here are the versions I'm running:

Seq 2025.2.14258
Seq CLI 2025.2.02428+68a069e7bc89ccf43c314767ec87638a2e2f36b5

Knowing the specific versions is important because behavior can change between releases. A bug that exists in one version might be fixed in another, or a feature might be introduced or deprecated. By providing the version information, we can ensure that we're all on the same page and that any potential solutions or workarounds are relevant to the specific environment. This also helps the Seq team, if they investigate this issue, to reproduce the behavior and identify the root cause.

Let's Discuss! Is This a Bug or a Feature?

So, what do you guys think? Is this inconsistent behavior a bug? Or is it a deliberate design choice? And if it's intentional, what's the reasoning behind it? I'm really curious to hear your thoughts and experiences with this. Maybe you've run into this before, or maybe you have some insights into how Seq handles properties under the hood.

Possible Explanations and Scenarios

Let's brainstorm some possible explanations for this inconsistency. Maybe the UI and CLI are designed for different use cases. Perhaps the UI is intended for more interactive, exploratory tasks where allowing duplicate keys provides flexibility. In contrast, the CLI might be geared towards automated, scripted operations where data integrity is paramount.

Another possibility is that the UI and CLI use different APIs or endpoints. It's conceivable that the UI uses a more forgiving API that accepts duplicate keys, while the CLI uses a stricter API that enforces uniqueness. This could be a deliberate choice to optimize performance or security in different contexts.

We also need to consider the potential impact on data consistency. If the UI allows duplicate keys, how does this affect search and filtering operations? Does Seq use the first value, the last value, or all values associated with a key? The answer to this question is crucial for understanding how to reliably query and analyze log data.

Furthermore, there might be underlying data structures or database constraints that influence this behavior. Seq might use a data store that inherently supports or restricts duplicate keys. Understanding these limitations can shed light on why the UI and CLI behave differently.

To get to the bottom of this, we might need to examine Seq's documentation, source code, or even reach out to the Seq team for clarification. In the meantime, sharing our thoughts and experiences can help us collectively understand the nuances of Seq's property handling.

Real-World Implications

Let's also think about the real-world implications of this behavior. Imagine a scenario where you're using the Seq CLI to automate the creation of API keys for different applications. If you accidentally include duplicate properties in your script, the CLI will throw an error and the key creation will fail. This could disrupt your workflow and require manual intervention.

On the other hand, if you're using the UI to explore log data and you add duplicate properties, you might inadvertently overwrite existing values and lose information. This could lead to incorrect analysis and flawed conclusions.

Understanding these potential pitfalls is essential for using Seq effectively and avoiding unexpected issues. By discussing these scenarios, we can develop best practices for property management and ensure data integrity.

Potential Solutions and Workarounds

If this inconsistency turns out to be a bug, the Seq team will likely address it in a future release. In the meantime, we might need to find workarounds to mitigate the issue. One possible workaround for the CLI is to ensure that your scripts never include duplicate properties. This might involve adding validation checks or using a different approach to property management.

For the UI, the key is to be aware of the potential for overwriting values when adding duplicate properties. Double-checking your input and being mindful of existing properties can help prevent accidental data loss.

Ultimately, the best solution is for Seq to provide a consistent and predictable behavior across the UI and CLI. This might involve standardizing the API or providing clear documentation on how duplicate properties are handled.

Wrapping Up

I'm eager to hear your thoughts on this! Let's get the conversation going and try to unravel this mystery together. Maybe we can even help the Seq team make Seq even better!