# Adding a New Provider to Your Configuration

> Markdown source of <https://docs.calebsargeant.com/computing/terraform/getting-started/adding-a-new-provider-to-configuration/>.

## Terraform Functions

- Built-in to Terraform
- Func_name(arg1, arg2, arg3, ...)
- Test in terrafrom console
- Several broad categories

### Common Function Categories

- Numeric
  - min(42, 13, 7)
- String
  - lower("TACOS")
- Collection
  - merge(map1, map2)
- Filesystem
  - file(path)
- IP network
  - cidrsubnet()
- Date and time
  - timestamp()

### Function Examples

``` text
#Configure networking
variable network_info {
default = "10.1.0.0/16" #type, default, description
}
#Returns 10.1.0.0/24
cidr_block = cidrsubnet(var.network_info, 8, 0)

#Returns 10.1.0.5
host_ip = cidrhost(var.network_info,5)

#Create ami map
variable "amis" {
  type = "map"
  default = {
    us-east-1 = "ami-1234"
    us-west-1 = "ami-5678"
  }
}
ami = lookup(var.amis, "us-east-1", "error")
```

## Terraform Commands

[m6_commands.txt](https://github.com/CalebSargeant/Getting-Started-Terraform/blob/master/m6/m6_commands.txt)

[modulesix.tf](https://github.com/CalebSargeant/Getting-Started-Terraform/blob/master/m6/modulesix.tf)

## Terraform Providers

- Iaas, Paas, Saas
- Community and HashiCorp
- Open source
- Resources and data sources
- Multiple instances

### Provider Example

``` text
provider "azurerm" {
subscription_id = "subscription-id"
client_id = "principal-used-for-access"
client_secret = "password-of-principal"
tenant_id = "tenant-id"
alias = "arm-1"
}
resource "azurerm_resource_group" "azure_tacos" {
name = "resource-group-name"
location = "East US"
provider = azurerm.arm-1
}
```

## Adding the AzureRM Provider

[modulesix.tf](https://github.com/CalebSargeant/Getting-Started-Terraform/blob/master/m6/modulesix.tf)

## Resource Arguments

- depends_on
- count
- for_each
- provider

### Depends_on and Count

``` text
resource "aws_instance" "taco_servers" {
count = 2
tags {
Name = "customer-${count.index}"
}
depends_on = [aws_iam_role_policy.allow_s3]
}
```

### For_each

``` text
resource "aws_s3_bucket" "taco_toppings" {
for_each = {
food = "public-read"
cash = "private"
}
bucket = "${each.key}-${var.bucket_suffix}"
acl = each.value
}
```

## Using the Count Argument

[modulesix.tf](https://github.com/CalebSargeant/Getting-Started-Terraform/blob/master/m6/modulesix.tf)