I am new to node-red and I am confused with the "message payload flow system".
I want to send a POST request that contains, among other params, files into the request payload. These files should be in an array called "files".
I read my files from my file system, this works fine, but in the function node, how do I build my POST payload?
So far I have this:
The problem is that the payload contains both files and I can't find a way to get them separately. How can I retrieve both my files, separately, into the BUILD-POST-REQ function?
The core Join node can be used to combine the output of parallel input streams. It has a number of modes that control how many input messages it will collect together.
These include a count of messages.
You can also choose how it combines the input messages, this can be as an array or as an object using the msg.topic as the key to the incoming msg.payload
Ok. I found A solution. But I don't know if this is a best practice. Feel free to correct me!
The idea is that after each file read, I store it in a new property of the msg object and then can access it later in the flow.
Related
In an electron application, I spawn a shell process proc to which the application
then talks via pipes, i.e. proc.stdin.write("cmd_to_shell_proc") and
proc.stdout.on("data", (data) => {//do sth with response}).
The data contains particular tokens from which it is clear what command had
been sent to the process. For most responses it is enough to know to which
command they reply, but there is one command I send from
two different components in my UI for which I would like to handle the
responses differently, depending on the UI component that sent it. I currently process the responses on the basis
of the string token contained in the data sent back from the process,
and I have not found a way to propagate any information about the originally calling process into the data handling in proc.stdout.on("data", ...) .
Is there any way to attribute the data being returned from the shell process to
the original caller of proc.stdin.write("<some command>")?
Any suggestions or advice would be highly appreciated!
I want store all the log that i put in application like,
What was input request and also what was output object.
Some interm states of about objects and about logic and output response in JSON and store
log.LogInformation("Final list of objects is" + JsonConvert.SerializeObject(finalSelectedItems));
Actually I want see latter on What was input request, what was different states of different objects and output result as I want this for debugging.
The system is dynamic and I can't replicate the scenarios when system doesn't behave as anticipated, So want see all information when system is not behaving properly
I have a use case where a mobile app records a long series of commands. Each command is a short, single word (or number). They can happen quickly one right after the other, but the use case does not care if it takes several seconds to get results back from the Cognitive server. It is currently being implemented as discrete asynchronous requests rather than streaming (seems to be more reliable for us).
Since results are coming back async, I see no easy way to map the result back to its corresponding request (and ultimately the app command). Can I embed a unique ID somewhere that will get passed back to me? Is there some other option?
You are using the SDK?
If you do recognizeOnce you get the result from the audio as a call result (synchronous)
If you do continuousrecognition there is currently no way to tag the audio segment.
When I use urllib.request.decode to get the python dictionary from JSON format it takes far too long. However upon looking at the data, I realized that I don't even want all of it.
Is there any way that I can only get some of the data, for example get the data from one of the keys of the JSON dictionary rather than all of them?
Alternatively, if there was any faster way to get the data that could work as well?
Or is it simply a problem with the connection and cannot be helped?
Also is the problem with the urllib.request.urlopen or is it with the json.loads or with the .read().decode().
The main symptoms of the problem is either taking roughly 5 seconds when trying to receive information which is not even that much (less than 1 page of non-formatted dictionary). The other symptom is that as I try to receive more and more information, there is a point when I simply receive no response from the webpage at all!
The 2 lines which take up the most time are:
response = urllib.request.urlopen(url) # url is a string with the url
data = json.loads(response.read().decode())
For some context on what this is part of, I am using the Edamam Recipe API.
Help would be appreciated.
Is there any way that I can only get some of the data, for example get the data from one of the keys of the JSON dictionary rather than all of them?
You could try with a streaming json parser, but I don't think you're going to get any speedup from this.
Alternatively, if there was any faster way to get the data that could work as well?
If you have to retrieve a json document from an url and parse the json content, I fail to imagine what could be faster than sending an http request, reading the response content and parsing it.
Or is it simply a problem with the connection and cannot be helped?
Given the figures you mentions, the issue is very certainly in the networking part indeed, which means anything between your python process and the server's process. Note that this includes your whole system (proxy/firewall, your network card, your OS tcp/ip stack etc, and possibly some antivirus on window), your network itself, and of course the end server which may be slow or a bit overloaded at times or just deliberately throttling your requests to avoid overload.
Also is the problem with the urllib.request.urlopen or is it with the json.loads or with the .read().decode().
How can we know without timing it on your own machine ? But you can easily check this out, just time the various parts execution time and log them.
The other symptom is that as I try to receive more and more information, there is a point when I simply receive no response from the webpage at all!
cf above - if you're sending hundreds of requests in a row, the server might either throttle your requests to avoid overload (most API endpoints will behave tha way) or just plain be overloaded. Do you at least check the http response status code ? You may get 503 (server overloaded) or 429 (too many requests) responses.
A seemingly simple question, but I am unsure of the node.js equivalent to what I'm used to (say from Python, or LAMP), and I actually think there may not be one.
Problem statement: I want to use basic, simple logging in my express app. Maybe I want to output DEBUG messages, or INFO messages, or just some stats to the log for consumption by other back-end systems later.
1) I want all logs message, however, to contain some fields: remote-ip and request url, for example.
2) On the other hand, code that logs is everywhere in my app, including deep inside the call tree.
3) I don't want to pass (req,res) down into every node in the call tree (this just creates a lot of parameter passing where they are mostly not needed, and complicates my code, as I need to pass these into async callbacks and timeouts etc.)
In other systems, where there is a thread per request, I will store the (req,res) pair (where all the data I need is) in a thread-local-storage, and the logger will read this and format the message.
In node, there is only one thread. What is my alternative here? What's "the request context in which a specific piece of code is running under"?
The only way I can think of achieving something like this is by looking at a trace, and using reflection to look at local variables up the call tree. I hate that, plus would need to implement this for all callbacks, setTimeouts, setIntervals, new Function()'s, eval's, ... and the list goes on.
What are other people doing?