logo
down
shadow

ELIXIR QUESTIONS

Redirect after POST using plug_cowboy (2.0)
Redirect after POST using plug_cowboy (2.0)
will help you I got a simple Plug post handler like this , There is no magic: you have to send HTTP 302 response:
TAG : elixir
Date : January 12 2021, 09:11 PM , By : user176445
Why doesn't Enum.filter work with a dictionary parameter?
Why doesn't Enum.filter work with a dictionary parameter?
it fixes the issue For this particular case you’d better use Kernel.match?/2 macro:
TAG : elixir
Date : January 11 2021, 11:39 AM , By : yossi
How to clean test DB after **all** test complete?
How to clean test DB after **all** test complete?
To fix the issue you can do You might use ExUnit.Callbacks.on_exit/2:
TAG : elixir
Date : January 02 2021, 06:48 AM , By : micate
Elixir Phoenix not loading env variable at runtime
Elixir Phoenix not loading env variable at runtime
This might help you I am trying to load an API key as a system env from my mac when starting up the phoenix server. What am I getting wrong? these are my steps: , Attributes are evaluated during compilation, so:
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Robin Buitenhuis
Elixir / Phoenix LiveView: How can I report exceptions to Rollbar?
Elixir / Phoenix LiveView: How can I report exceptions to Rollbar?
it helps some times But when my LiveView code crashes, I don't get this assurance. The LiveView process will recover from the crash and (as I understand it) revert to its last known healthy state
TAG : elixir
Date : January 02 2021, 06:48 AM , By : noboruwatanabe
Elixir / Phoenix: Why do route helpers require @conn?
Elixir / Phoenix: Why do route helpers require @conn?
wish of those help The connection has additional information beyond the endpoint. For example, if you have two routers in your application, where one calls the other, you need to be able to assemble the original path back together (this is typically
TAG : elixir
Date : January 02 2021, 06:48 AM , By : cjdavis
Phoenix Elixir : cannot escape function in elixir compiler
Phoenix Elixir : cannot escape function in elixir compiler
like below fixes the issue cannot escape Function. The supported values are: ... remote functions in the format Mod.fun/arity
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Noah
Storing calculated column to use in order_by and select
Storing calculated column to use in order_by and select
Any of those help You could use an alias to reuse that calculated value, although you'll have to use fragments. It's not such a tradeoff! This article details the logic nicely.In your use case, it would give something like this:
TAG : elixir
Date : January 02 2021, 06:48 AM , By : user161314
Reverse and Concat a List
Reverse and Concat a List
hope this fix your issue I'd say it would be more idiomatic to use the ++ operator instead of Enum.concat. (Note that ++ requires the arguments to be lists, whereas Enum.concat accepts any kind of enumerable.)
TAG : elixir
Date : January 02 2021, 06:48 AM , By : kdietz
Import module from another directory
Import module from another directory
like below fixes the issue I figured out 1 way of doing this but hoping there might be a better way. ...I added -pa argument (which allows you to prepend other paths to the Erlang code path).
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Keniwan
Building association between two tables before inserting
Building association between two tables before inserting
wish of those help As it might be seen from the error message, Repo.get_by/2 returns %Accreditor.Role.Roles{} struct, which has no role field. And you are trying to pass it to the function accepting a parameter that is to be pattern matched on %{role
TAG : elixir
Date : January 02 2021, 06:48 AM , By : user126922
The database for Rumbl.Repo couldn't be created: killed
The database for Rumbl.Repo couldn't be created: killed
it helps some times Your Postgres database is not running or not open on this port. If you don't want to handle with postgres issues or are not familiar with that, take a look on this post about how to have it running on a docker container.
TAG : elixir
Date : January 02 2021, 06:48 AM , By : UnKnownUser
Can you create conditional plugs in elixir?
Can you create conditional plugs in elixir?
I wish this help you You got it almost right, you only forgot to pass the second argument to call!A module plug is a module with two functions: init/1 and call/2. In order to invoke any module plug dynamically, you need to invoke init/1 with the defa
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Comfly
Elixir: I'm getting an error from a simple addition function
Elixir: I'm getting an error from a simple addition function
I hope this helps . I created a simple function in Elixir that increments a value from a tuple by 1. , In your function definition here:
TAG : elixir
Date : January 02 2021, 06:48 AM , By : user186435
The task "docs" could not be found. Did you mean "do"?
The task "docs" could not be found. Did you mean "do"?
like below fixes the issue The mix docs task is available with ExDoc. Make sure that you have the dependency installed. Make sure to check out the docs and install it properly. Then you'll be able to use the mix docs command.This is how to install it
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Pavel K.
How can I use Elixir's doctest to test a protocol implementation?
How can I use Elixir's doctest to test a protocol implementation?
it helps some times It turns out that defimpl defines a module behind the scenes. This can be found via the impl_for function on the protocol:
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Boyer C.
How to integrate test.watch with `iex -S mix phx.server`
How to integrate test.watch with `iex -S mix phx.server`
this will help Oops, nevermind. Turns out I just needed to increase the inotify limit.
TAG : elixir
Date : January 02 2021, 06:48 AM , By : snk
String concatenation: binary syntax v. operator <>
String concatenation: binary syntax v. operator <>
will be helpful for those in need Yes. The /2 operator is a macro that transforms the code into the special form.
TAG : elixir
Date : January 02 2021, 06:48 AM , By : JackIT
Dialyzer warnings about pattern_match_cov on Gettext module
Dialyzer warnings about pattern_match_cov on Gettext module
hop of those help? As a workaround until the bug is fixed, I made .dialyzer_ignores.exs with the following contents in the root directory of umbrella project.
TAG : elixir
Date : January 02 2021, 06:48 AM , By : mitry
Ecto.Repo.delete/2: When looking at a type specification, how do you know if there is a default value?
Ecto.Repo.delete/2: When looking at a type specification, how do you know if there is a default value?
wish helps you Browsing through the docs and a similar question's answer, it seems that default arguments are not supported in typespecs. This Github issue from 2014 explains some of the tradeoffs to such a feature. How would one know the second argu
TAG : elixir
Date : January 02 2021, 06:48 AM , By : Grace Jones
How to have a key value output
How to have a key value output
should help you out If you want to get both the number and the sum of its digits, you should return a tuple or a list in the mapping function, like so:
TAG : elixir
Date : January 02 2021, 06:48 AM , By : 40a
How test controller authorization
How test controller authorization
Any of those help The test is good, your code is not.your authorize function return a conn, but you never use it on the index function.
TAG : elixir
Date : December 30 2020, 04:08 PM , By : barefootChild
Serve Static Images with Phoenix Elixir
Serve Static Images with Phoenix Elixir
To fix this issue Unfortunately because the email client is the decision point there isn't too much you can do. Your best bet would be to ask your recipients to whitelist your email address.
TAG : elixir
Date : December 28 2020, 01:32 PM , By : acolomba
Elixir's GenServer handle_call, handle_info, handle_cast not being invoked
Elixir's GenServer handle_call, handle_info, handle_cast not being invoked
Hope this helps DynamicSupervisor is a custom implementation of GenServer behaviour.The only overridable function it has is child_spec/1.
TAG : elixir
Date : December 25 2020, 02:01 PM , By : Fernando
Running multiple process in parallel elixir
Running multiple process in parallel elixir
I hope this helps . There is the only one message from the mailbox processed by each process at any time, even despite handle_cast/2 returns immediately. The process would ultimately finish processing the previous message before accessing the one wai
TAG : elixir
Date : December 25 2020, 06:49 AM , By : Priya
What do the on_delete options in Ecto.Migrations.references/2 do?
What do the on_delete options in Ecto.Migrations.references/2 do?
around this issue This is actually a SQL question at root.https://github.com/elixir-ecto/ecto_sql/blob/52f9d27a7ad86442f442bad2f7ebd19ba09ddc61/lib/ecto/adapters/myxql/connection.exL902-L905
TAG : elixir
Date : December 24 2020, 05:01 AM , By : ck1
How to differentiate errors in Elixir's `with` macro?
How to differentiate errors in Elixir's `with` macro?
wish help you to fix your issue You can wrap your with lines on descriptive tuples and still assert on the return you want, this will then allow you to discern/provide feedback where the error was.
TAG : elixir
Date : December 22 2020, 08:01 PM , By : Singularity
Empty a file and store a state permanently
Empty a file and store a state permanently
will be helpful for those in need I would like to use a file to store some variables. The file will be rewritten every 10/15 minutes, and the data should stay there after the app shut down. Is there a solution which is not closing and opening the fil
TAG : elixir
Date : December 22 2020, 02:01 AM , By : Rohii
Error when updating user due to validation on virtual field
Error when updating user due to validation on virtual field
I hope this helps you . After inserting data to my database, I find it difficult to update the record because of required validation on two virtual fields (:password and :password_confirmation) which I do not need during updates. I only require this
TAG : elixir
Date : December 21 2020, 01:01 PM , By : micaleel
How to insert unescaped text in Elixir Temple template?
How to insert unescaped text in Elixir Temple template?
hope this fix your issue I've asked this question directly in Temple github issues and got an answer from @mhanberg. So basically to put an unescaped text in the template we should use this:
TAG : elixir
Date : December 18 2020, 10:29 AM , By : ianium
Problem serving multiple dynamic images with Phoenix (some load, some dont)
Problem serving multiple dynamic images with Phoenix (some load, some dont)
I wish did fix the issue. Solution was to work with absolute paths. Apparently Phoenix sometimes changes the current working directory, for example when code reloading, and thus the relative path fails.
TAG : elixir
Date : December 06 2020, 11:17 PM , By : August
Interpolating Map Keys with Elixir
Interpolating Map Keys with Elixir
will be helpful for those in need Use Map.put_new/3:
TAG : elixir
Date : December 05 2020, 12:09 PM , By : geo
Ecto - querying a table based on an association
Ecto - querying a table based on an association
it helps some times I would recommend making a query that does the join and then filters as so:
TAG : elixir
Date : November 29 2020, 12:01 PM , By : Steve O.
Getting the count of an iteration completion elixir
Getting the count of an iteration completion elixir
it should still fix some issue Make the accumulator in the main loop to collect both dates and counts with a help of Enum.sum/1:
TAG : elixir
Date : November 29 2020, 12:01 PM , By : Mena
Elixir - pass partial output through pipe operator
Elixir - pass partial output through pipe operator
it should still fix some issue Since you want to discard the first element of the tuple and only pass the second to Map.pop, you can add |> elem(1) to the pipeline:
TAG : elixir
Date : November 28 2020, 03:01 PM , By : nseibert
pattern match HTTpoison response Elixir
pattern match HTTpoison response Elixir
this one helps. HTTPoison.get! will raise an exception, not return one, so you need to use try ... rescue ...:
TAG : elixir
Date : November 27 2020, 11:01 PM , By : user179271
Is it possible to instantiate a new struct, from a variable, containing a reference to that struct?
Is it possible to instantiate a new struct, from a variable, containing a reference to that struct?
To fix the issue you can do Consider the following example. , I believe this may work:
TAG : elixir
Date : November 27 2020, 03:01 PM , By : Skee
'Case X do' always take the first option
'Case X do' always take the first option
I think the issue was by ths following , This is exactly how a case expression should be working. You put the value of value into the key variable. If you want to match value against the current value of the key variable instead of shadowing it, you
TAG : elixir
Date : November 26 2020, 03:04 PM , By : Jason Vance
Stop reduce_while with tuple
Stop reduce_while with tuple
hope this fix your issue If you want to pattern match the response from your function, use case:
TAG : elixir
Date : November 26 2020, 03:01 PM , By : CookingCoder
Elixir : Correct way to start child using Dynamic Supervisor
Elixir : Correct way to start child using Dynamic Supervisor
I hope this helps you . In your case you'll need to do three things:Set up the child spec correctly before starting it from the DynamicSupervisor:
TAG : elixir
Date : November 26 2020, 04:01 AM , By : Vasiliy
Transform data structure
Transform data structure
hope this fix your issue The problem you are having is with the scoping rules which I explain in Fill a List with a for-loop.I haven't changed your original code too much in order to answer your question. To fix your issue you can change your Enum.ea
TAG : elixir
Date : November 25 2020, 09:00 AM , By : tjh0001
How to add aliases and imports into my own mix under umbrella application in Elixir?
How to add aliases and imports into my own mix under umbrella application in Elixir?
fixed the issue. Will look into that further I have an Umbrella application in Elixir. , The file should be .iex.exs not db.iex.exs.
TAG : elixir
Date : November 23 2020, 03:01 PM , By : user182203
How to implement setters on Ecto models (or Elixir structs)
How to implement setters on Ecto models (or Elixir structs)
I wish this helpful for you Currently, there is no mechanism. The best you can do is to create a function like:
TAG : elixir
Date : November 22 2020, 03:03 PM , By : xie renhui
Printing a Stream in Elixir
Printing a Stream in Elixir
To fix this issue You need explicit parentheses for your Stream.reject function. See Why Can39;t I Chain String.replace? for a detailed explanation.
TAG : elixir
Date : November 22 2020, 09:00 AM , By : Jack
Check if a value is a Keyword List
Check if a value is a Keyword List
around this issue Turns out there is a built in solution; the Keyword module exports a keyword?/1 method:
TAG : elixir
Date : November 20 2020, 11:01 PM , By : OllieDoodle
plug in phoenix controller
plug in phoenix controller
wish helps you I would split the code in two steps - first attempting to authenticate the user, loading from the database and assigning to the connection - you can always run this one, and simply assign nil, a special guest user or nothing, whatever
TAG : elixir
Date : November 20 2020, 11:01 PM , By : Jason Haar
Testing a file upload in phoenix/elixir
Testing a file upload in phoenix/elixir
around this issue Put a file in your test directory somewhere (maybe test/fixtures) then use the Plug.Upload struct:
TAG : elixir
Date : November 20 2020, 09:01 AM , By : Pancilobak
Elixir generating content
Elixir generating content
Does that help Variables in Elixir are immutable. Your code is creating a brand new content in every iteration of for . For this particular code, you make use of the fact that for returns a list of the evaluated value of the do block:
TAG : elixir
Date : November 19 2020, 11:01 PM , By : Cube_Zombie
Configure request timeout in Phoenix?
Configure request timeout in Phoenix?
will be helpful for those in need This is by no means a responsibility of the web-server/framework. Cowboy has no clue (and it should not have!) about what’s going on in the application, it serves the connections. Phoenix could take care of that, but
TAG : elixir
Date : November 19 2020, 03:01 PM , By : Jason Jennings
How do I resolve the following errors while creating a Phoenix project using Mix?
How do I resolve the following errors while creating a Phoenix project using Mix?
wish help you to fix your issue Okay, I resolved the issue.The problem was with a stale(?) hex.ez file in the directory ~/.mix/archives/. After I removed that file by issuing the command mix archive.uninstall hex.ez, everything is now working fine.
TAG : elixir
Date : November 18 2020, 11:01 PM , By : Fred Morrison
Elixir Phoenix global variable plug
Elixir Phoenix global variable plug
around this issue The url is generated from your endpoint.url and not the host for the Plug.ConnFrom https://github.com/phoenixframework/phoenix/blob/8fe0538fd7be2adb05e2362b02fa8bd6bf3c6c46/lib/phoenix/router/helpers.exL13:
TAG : elixir
Date : November 18 2020, 09:01 AM , By : uxn
Requiring third party libraries in Elixir
Requiring third party libraries in Elixir
this one helps. To use Erlang libraries and code in your Elixir projects, here's the key:
TAG : elixir
Date : November 14 2020, 11:01 PM , By : Killercode
Insert/Update nested objects in ecto model
Insert/Update nested objects in ecto model
I wish did fix the issue. With a model such as , Just found out that if you change the model like this:
TAG : elixir
Date : November 13 2020, 11:01 PM , By : Umang
before_action :setup equivalent in Phoenix
before_action :setup equivalent in Phoenix
help you fix your problem You could try to use the action/2 controller method. From the controller docs:
TAG : elixir
Date : November 13 2020, 03:01 PM , By : Daniel Halsey
store variables in a module
store variables in a module
like below fixes the issue This Token is only valid for some time and I only want to get a new token when the old one is expired
TAG : elixir
Date : November 13 2020, 05:40 AM , By : CM.
How do you define constants in Elixir modules?
How do you define constants in Elixir modules?
Does that help In Ruby, if one were defining constants in classes, they would define them using all caps. For example: , You can prepend your variable name with @:
TAG : elixir
Date : November 10 2020, 09:01 AM , By : johntynan
How to render arc_ecto image in Phoenix framework template?
How to render arc_ecto image in Phoenix framework template?
it should still fix some issue I written below code in my template. , Self solved.I found below issue.
TAG : elixir
Date : November 06 2020, 04:03 AM , By : Bo.
Elixir - Merge 2 List of Lists (like columns)
Elixir - Merge 2 List of Lists (like columns)
it should still fix some issue Whenever you want to iterate over two enumerables simultaneously, you should think about using Enum.zip/2. This is how I'd do it with Enum.zip/2 and for:
TAG : elixir
Date : November 05 2020, 03:01 PM , By : Jay Crockett
How to get Phoenix to listen on port 4000?
How to get Phoenix to listen on port 4000?
hope this fix your issue I'm trying to get my Phoenix app to listen on port 4000, but it's not working. First, I generate my production app with MIX_ENV=prod mix release --env=prod. Then, I rsync the _build directory to my server. Then I run PORT=400
TAG : elixir
Date : November 03 2020, 03:01 PM , By : Crilledk
How to create unbound variable part of an array(a method param) in a method created by macros
How to create unbound variable part of an array(a method param) in a method created by macros
I hope this helps you . In a phoenix app, I'm trying to implement authorization like this , You need to define your macro like this:
TAG : elixir
Date : November 01 2020, 09:01 AM , By : user94076

shadow
Privacy Policy - Terms - Contact Us © scrbit.com