suryaniwati

suryaniwati

Crawler Data

Hi

How can I crawl a website content and save the contents to database?

Any favorite library?

Thanks,
Ani

Most Liked

idi527

idi527

I usually use httpoison with floki. There has been some discussion about it

You can replace floki with

For any interaction with a database (postgres by default) you can use ecto.

So my approach would be (roughly) like this:

defmodule Crawler do
  def crawl!(url) do
    %HTTPoison.Response{body: body, status: 200} = HTTPoison.get!(url)
    html = Floki.parse(body)
    contents = Floki.find(html, "article") # or whatever you are interested in
    # see ecto docs to understand what Repo does
    Crawler.Repo.insert!(%Article{contents: contents})
    urls =
      html
      |> Floki.find("a")
      |> Enum.map(fn anchor -> Floki.attribute(anchor, "href") end)
    # spawn more tasks to crawl other pages, or keep crawling in the current process
  end
end
Eiji

Eiji

It’s not a “tool from god”, but it’s very easy to setup and it have very simple commands, so I think that’s best answer for all members (including beginners).

Eiji

Eiji

@suryaniwati: Let me summary everything:

Similar topic

We have already talked about tools for collect (scrape) data from web pages here:

Database

Easiest way to validate and save data into database is using Ecto library:

Rust dependencies

And for your last question:

It’s as simple as install rust stable (using asdf tool). The rest is as easy as add elixir dependencies and compile project. :smile:

Full setup

  1. Ensure you have dependencies for compile sources (depends on your OS/distro)
  2. Install asdf
  3. Install Erlang plug-in for asdf
  4. Install Erlang
  5. Set Erlang version
  6. Install Elixir plug-in for asdf
  7. Install Elixir
  8. Set Elixir version
  9. Add Rust plug-in for asdf
  10. Install Rust
  11. Set Rust version
  12. Add PostgreSQL plug-in for asdf
  13. Install PostgreSQL database
  14. Set PostgreSQL version

Example script

# Contents of file: "setup_environment.sh"

#!/bin/bash

# asdf
git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.4.0
echo -e '\n. $HOME/.asdf/asdf.sh' >> ~/.bashrc
echo -e '\n. $HOME/.asdf/completions/asdf.bash' >> ~/.bashrc
source ~/.bashrc

# Erlang
asdf plugin-add erlang https://github.com/asdf-vm/asdf-erlang.git
asdf install erlang 20.2.2
asdf global erlang 20.2.2

# Elixir
asdf plugin-add elixir https://github.com/asdf-vm/asdf-elixir.git
asdf install elixir 1.6.1
asdf global elixir 1.6.1

# Rust
asdf plugin-add rust https://github.com/code-lever/asdf-rust.git
asdf install rust stable
asdf global rust stable

# PostgreSQL
asdf plugin-add postgres https://github.com/smashedtoatoms/asdf-postgres.git
asdf install postgres 10.1
asdf global postgres 10.1

Notes

  1. Feel free to modify script and install different versions of packages or different databases.

Other helpful resources

Finally this article should be helpful for setup Ecto 2 based project:

Last Post!

axelson

axelson

Scenic Core Team

Plus it supports so many different languages. I was so tired of having separate version managers for each language, it’s super nice to have just one version manager.

Where Next?

Popular in Questions Top

Brian
What is the proper way to load a module from a file in to IEX? In the python world, doing something like this pretty standard: from ....
New
ovidiubadita
Hey all, I discovered Elixir and I love it. I always wanted to learn a functional programming and I intended to go for Haskell, but afte...
New
lastday4you
I wanted to check elixir version in phoenix because i found that my elixir is 1.5 but when i use Enum.chunk_by it said the function is un...
New
nsuchy
Hi. I’ve noticed that Windows Powershell has it’s own IEX command and you cannot access Elixir’s IEX due to the conflict. This isn’t a cr...
New
pmjoe
I have a relationship of love and hate with Elixir. Lots of things are just absolutely right, but there are some things that are kind of ...
New
vrod
I am using the Starship cross-shell prompt – it seems pretty nice, but I get some errors: [WARN] - (starship::utils): Executing command ...
New
senggen
Erlang/OTP 25 [erts-13.2.2] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] 15:22:35.803 [error] gen_event {lager_file_backend...
New

Other popular topics Top

New
jononomo
For some reason my phoenix channels are working for me in my local dev environment, but as soon as I deploy via Docker, I get a 403 error...
New
dokuzbir
I want to highlight html closing tags when i click a html tag. That works in .html files but doesnt work for html.eex templates. How can...
New
dblack
I’ve got an issue with an app and I’ve no idea of how to troubleshoot it. I’m hoping someone here might have seen something similar. I p...
New
sergio
Kind of like when jquery came out, it was super necessary. Existing drag and drop libraries have a bunch of baggage to support old browse...
New
senggen
Erlang/OTP 25 [erts-13.2.2] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] 15:22:35.803 [error] gen_event {lager_file_backend...
New

We're in Beta

About us Mission Statement